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  • 1975-1979  (1.771)
  • 1965-1969
  • 1915-1919
  • 1910-1914
  • 1890-1899
  • 1860-1869
  • 1976  (1.771)
  • Organic Chemistry  (693)
  • Life and Medical Sciences  (572)
  • Physics  (492)
  • Insulin
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  • 1975-1979  (1.771)
  • 1965-1969
  • 1915-1919
  • 1910-1914
  • 1890-1899
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Jahr
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  • 1
    Digitale Medien
    Digitale Medien
    Kohlenhydrat- und Fettstoffwechsel der Skelettmuskulatur unter Ruhebedingungen und bei kurzfristiger submaximaler Arbeit am Modell des perfundierten Hinterbeins der Ratte (1976)
    Springer
    Research in experimental medicine 168 (1976), S. 23-33 
    Details
    ISSN: 1433-8580
    Schlagwort(e): Muscle metabolism ; exercise ; insulin ; glucose uptake ; lipolysis ; Muskelstoffwechsel ; Insulin ; Glukoseaufnahme ; Muskelkontraktion ; Basislipolyse
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Am Modell der perfundierten Hinterpfote der Ratte wurde der Muskelstoffwechsel unter Ruhebedingungen und während elektrischer Reizung in Gegenwart und Abwesenheit von Insulin untersucht. Die basale Glukoseaufnahme wurde sowohl durch Muskelkontraktionen als auch durch physiologische Mengen von Insulin um den Faktor 3 gesteigert. Insulin und Muskelkontraktionen wirkten additiv auf die Glukoseaufnahme. Muskelarbeit führte zu einem 7 – 8fachen Anstieg der Lactatproduktion, unabhängig, ob Insulin dem Perfusionsmedium zugefügt war oder nicht. Die arbeitsbedingte Lactatproduktion überstieg die gleichzeitige Glukoseaufnahme und korrespondierte mit einem signifikanten Abfall des Muskelglykogen-Gehaltes. Muskelkontraktionen führten zu einer gesteigerten Lipolyse. In Ruhe hatten weder Corticosteron noch Thysoxin einen Einfluß auf die Lipolyse. Zugabe von Serum zum Perfusionsmedium bewirkte dagegen eine um den Faktor 2 gesteigerte Lipolyse, gemessen an der Gycerinproduktion. Aus den Ergebnissen wird geschlossen, daß die Glykogenolyse über das Phosphorylasesystem durch kurzdauernde Muskelkontraktionen alleine prompt zu stimulieren ist, die Lipolyse dagegen nicht.
    Notizen: Summary The influence of insulin on muscle metabolism at rest and during electrically stimulated exercise was examined in the perfused rat hind limb. Basal glucose uptake of muscle tissue was enhanced threefold both by muscle contraction an by addition of physiological amounts of insulin. A further increase in glucose uptake was seen, when muscle was exercised in the presence of insulin. Lactate production rose 7 – 8fold by contractions. Insulin had no additional effect on lactate production during exercise. The work-induced lactate output exceeded glucose uptake, corresponding to a significantly reduced glycogen content after exercise. Basal lipolysis was not stimulated by muscle contractions. At rest the addition of both corticosterone and thyroxine did not increase the basal lipolysis. Yet, glycerol release rose twofold by the addition of serum to the perfusion medium. It is assumed that in the perfused rat hind limb glycogenolysis will promptly be stimulated by muscle contractions, whereas lipolysis can not be enhanced by exercise alone.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01851730
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  • 2
    Digitale Medien
    Digitale Medien
    A morphological study of the prostatic lobes and the seminal vesicles of castrated rats injected with oestradiol and/or insulin (1976)
    Springer
    Urological research 4 (1976), S. 63-69 
    Details
    ISSN: 1434-0879
    Schlagwort(e): Prostatic lobes ; Seminal vesicles ; Morphology ; Oestradiol ; Insulin ; Castrated rats
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The growth of the ventral and dorsolateral prostate, the coagulating glands and the seminal vesicles was studied morphologically in castrated rats following 21 daily injections of oestradiol benzoate or protamine zinc insulin alone or in combination. Oestradiol benzoate was given in daily doses of 0.010 mg, protamine zinc insulin in daily doses of 10 IU. In the ventral and dorsolateral prostate oestradiol had an androgen-like action inducing epithelial growth and secretory activity in the epithelium. In the seminal vesicles and coagulating glands oestradiol induced an increased fibromuscular growth. Protamine zinc insulin induced growth and secretory activity in the dorsolateral prostate, while no such effect was observed in the other accessory reproductive glands. Protamine zinc insulin accentuated the androgen-like action of oestradiol benzoate on the epithelium of the dorsolateral prostate but did not influence on the increased fibromusular growth seen after oestradiol in the coagulating glands and the seminal vesicles.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00256319
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  • 3
    Digitale Medien
    Digitale Medien
    Serum insulin levels in school children aged 9–12 in Westland, Holland (1976)
    Springer
    Diabetologia 12 (1976), S. 313-317 
    Details
    ISSN: 1432-0428
    Schlagwort(e): Insulin ; insulin resistance ; blood glucose ; epidemiology ; diabetes mellitus ; child
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary In a study of risk factors for cardiovascular disease in 2388 school children aged 9–12 years carried out in Westland, Holland, serum insulin levels at one hour after an oral challenge of 50 g glucose were measured in a systematically selected subsample of 715 children. The distribution and associations of serum insulin in these children are described. The mean insulin values were 24.6 μU/ml for boys and 32.0 μU/ml for girls. The difference between these means was statistically significant and remained so even after taking measures of adiposity into account. Insulin values were positively related to levels of plasma sugar and systolic blood pressure in both sexes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00420974
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  • 4
    Digitale Medien
    Digitale Medien
    Postmaturity in the rat: Impairment of insulin, glucagon, and glycogen stores (1976)
    Springer
    Diabetologia 12 (1976), S. 429-436 
    Details
    ISSN: 1432-0428
    Schlagwort(e): Insulin ; glucagon ; glycogen ; blood glucose ; progesterone ; fetus ; neonate ; placenta ; postmaturity ; neonatal hypoglycemia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Prolonged gestation (2 extra days in utero) was obtained by daily subcutaneous injection of progesterone (2.5 mg) to pregnant rats from day 20.5 post coïtum (p. c.) through day 22.5 p. c. after reduction of the litter to 6 fetuses on day 14.5 p. c. Exogenous progesterone per se or litter reduction were without effect on fetal pancreas or fetal liver. Plasma insulin, insulin and glucagon in the pancreas, and liver glycogen stores have been systematically measured in postmature animals and in controls during the perinatal period. In 23.5 day-old postmature as compared to 21.5 day-old normal fetuses, the intrauterine mortality was increased (26%), the body weight was increased by 30%, the liver weight was decreased by 20%, the glycogen content of liver was dramatically depleted (1.1±0.2mg/g body weight on day 23.5 p.c. against 6.7±0.3 on day 21.5 p.c), the plasma insulin was lowered by 63% and the blood glucose level was normal. In postmature neonates during the first day of life the mortality rate was considerable (40%) and a dramatic fall of blood glucose was observed 6 hours after birth. The accumulation of insulin and glucagon in the pancreas, which normally occurs in the two first days after birth, was much lower in the postmature fetuses: in 23.5 day-old fetuses as compared to 2 day-old normal newborns of the same gestational age the insulin content was only 50% and the glucagon content 69%. The deficit of insulin accumulation in the postmature pancreas lasted at least five days. The ability of the endocrine pancreas to recover from this alteration was well shown by the lack of diabetes when the animals were examined three weeks later by a glucose tolerance test. These findings suggest that the drop of plasma insulin is a prime factor in causing the lack of glycogen stores in prolonged fetuses and the impairment of glycogen stores appears to be an important feature of postmaturity, since neonates exhibit, in these conditions, a lethal drop of blood glucose as glycogenolysis operates on very low glycogen stores.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01219505
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  • 5
    Digitale Medien
    Digitale Medien
    Interactions of polypeptide hormones with cell membrane specific receptors: Studies with insulin and glucagon (1976)
    Springer
    Diabetologia 12 (1976), S. 83-100 
    Details
    ISSN: 1432-0428
    Schlagwort(e): Insulin ; glucagon ; polypeptide hormones ; receptors ; plasma membrane ; isolated liver cells ; isolated fat cells ; liver membranes ; fat cell membranes ; cardiac membranes ; adenylate cyclase ; monoiodoinsulin ; monoiodoglucagon ; 125I-insulin binding ; 125I-glucagon binding ; radioreceptorassay ; structure-function relationships ; modified insulins ; obese hyperglycémic (ob/ob) mouse ; obesity ; receptor defect ; insulin resistance ; insulin-dextran-ferritin ; visualization of binding sites
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00428972
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  • 6
    Digitale Medien
    Digitale Medien
    Secretin and insulin: Response to intraduodenal acid (1976)
    Springer
    Diabetologia 12 (1976), S. 145-148 
    Details
    ISSN: 1432-0428
    Schlagwort(e): Insulin ; secretin ; intraduodenal acid ; enteroinsular axis ; vagus ; pancreas
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Immunoreactive secretin (IRS) and immunoreactive insulin (IRI) levels were measured in humans and dogs following the intraduodenal instillation of hydrochloric acid. IRS levels rose after acid in both instances, but a concomitant rise in peripheral IRI levels was not noted. Premedication of the humans with Scopolamine prevented a rise of IRS in the human subjects. It is concluded that the endogenous release of IRS alone does not result in increased IRI levels in peripheral blood and that IRS release may be under vagal control.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00428980
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  • 7
    Digitale Medien
    Digitale Medien
    Circular dichroism studies on the interaction of sulfonylureas with insulin (1976)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 293 (1976), S. 97-99 
    Details
    ISSN: 1432-1912
    Schlagwort(e): Insulin ; Sulfonylureas ; Circular dichroism ; Conformation change
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The interaction of 5 sulfonylurea derivatives with insulin was investigated by means of circular dichroism measurements. It was found that all sulfonylureas investigated decrease the ellipticity band of insulin at 208 nm, whereas the band at 222 nm remains unaffected. It is suggested that these observations are due to a change of the insulin conformation, provoked by the interaction of the drugs with insulin. It is assumed that such an effect on the insulin conformation can influence the binding properties of insulin, e.g. in respect to the insulin aggregation, to the binding to insulin antibodies and to a bound, inactive form of insulin in the plasma. Some other drugs have similar, but mostly smaller effects on the CD spectrum of insulin. Therefore, the importance of these observations for the hypoglycaemic action of the sulfonylureas is not yet clear.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00498876
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  • 8
    Digitale Medien
    Digitale Medien
    Disappearance of insulin response after enzymatic treatment of sodium-transporting amphibian epithelia (1976)
    Springer
    Pflügers Archiv 364 (1976), S. 99-101 
    Details
    ISSN: 1432-2013
    Schlagwort(e): Frog skin epithelium ; Toad colon mucosa ; Collagenase treatment ; Insulin ; Sodium transport
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Amphibian epithelia specialized in transcellular sodium transport lose their capacity to react to insulin by a stimulation of this process upon treatment with collagenase; baseline activity and responsiveness to other hormones (vasopressin, aldosterone) bringing about such a stimulation are preserved. This renders it likely that proteases contaminating most collagenase preparations exert a detrimental effect on the receptors held responsible for interaction between insulin and its target cells in the tissues examined.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01062919
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  • 9
    Digitale Medien
    Digitale Medien
    The circadian rhythm of synthesis and catabolism of cholesterol (1976)
    Springer
    Archives of toxicology 36 (1976), S. 267-276 
    Details
    ISSN: 1432-0738
    Schlagwort(e): Circadian rhythm of HMG-CoA reductase and cholesterol-7α-hydroxylase ; Influences of starvation ; of cholesterol ; Bile acid and cholestyramine feeding ; Thyroxin ; Insulin ; Hypophysectomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Der Circadianrhythmus von HMG-CoA Reduktase und Cholesterin-7α-hydroxylase (niedrige Werte am Tage, ansteigende in der Nacht mit Maximum um 24.00 Uhr) wird unter verschiedenen Bedingungen an Ratten untersucht. Intragastrale Applikation von Cholestyramine (Bindung von Gallensäuren im Darm) führt zu erhöhten Enzymaktivitäten unter Vergrößerung des Rhythmus'. Cholsäure-Fütterung hemmt beide Enzymaktivitäten (Cholesterin-Zufuhr hemmt die HMG-CoA Reduktase). Im Hungerzustand entwickelt sich nach 24 Std ein gedämpfter Rhythmus bei beiden Enzymen. Eine 20%ige Fett-Diät (vorwiegend gesättigte Fettsäuren) senkt die Enzymaktivität durch Reduzierung der Maximalwerte bei nahezu unveränderten Niedrigwerten. Die nach Thyreoidektomie erniedrigten Enzymaktivitäten können durch Hormonsubstitution normalisiert werden. Experimentell erhöhte Hormonspiegel bleiben ohne Effekt. Insulinbehandlung des Normaltieres hemmt die Cholesterin-7α-hydroxylase, beeinflußt die HMG-CoA Reduktase nicht. Im diabolischen Tier zeigt sich umgekehrt eine erhöhte Cholesterin-7α-hydroxylase und eine gehemmte HMG-CoA Reduktase Aktivität. Insulinbehandlung dieser Tiere normalisiert die HMG-CoA Reduktase, während die Cholesterin-7α-hydroxylase gehemmt wird. Die geschwindigkeitsbestimmenden Enzyme des Cholesterin-Stoffwechsels werden peripher reguliert durch ihre Produkte im Sinne einer negativen feedback-Koppelung. Im Gegensatz dazu können Hormone gleich und gegensinnige Effekte auf die beiden Enzyme ausüben und so Mittel einer übergeordneten Steuerung darstellen. Alle besprochenen Regulationsmöglichkeiten wirken modifizierend auf den Circadianrhythmus mit Ausnahme der Hypophysektomie. Nach Entfernen der Hypophyse ist der Circadianrhythmus nicht mehr nachweisbar. Um gültige Aussagen über biochemische oder pharmakologische Wirkungen auf diese Enzyme machen zu können, muß der circadiane Rhythmus durch Messungen zu mehreren Tageszeiten berücksichtigt werden (Beispiel Fett-Diät); denn nur die Fläche aus Enzymaktivität und Tageszeit ist proportional dem Umsatz einer Substanz.
    Notizen: Abstract The circadian rhythms of HMG-CoA reductase and cholesterol-7α-hydroxylase (low values during light, rising in the evening with maximum at 12.00 p.m.) are investigated in rats under diverse conditions. Intragastral administration of cholestyramine (bile acid-absorbing resin) leads to an increased rhythm of both enzymes. Feeding of cholic acid (or cholesterol) reduces the activity of both enzymes (of HMG-CoA reductase and cholesterol — 7α-hydroxylase, respectively). In starved rats enzyme activities are lowered, too; a damped rhythm reappears after 24 h. A 20% fat diet (containing saturated fatty acids predominantly) markedly reduces the high values. Enzyme activities inhibited after thyroidectomy can be normalized by thyroxin substitution. Thyroxin administration in the normal remains without effect. Four-day insulin treatment of the normal inhibits cholesterol-7α-hydroxylase, has no effect on HMG-CoA reductase. In the untreated diabetic rat cholesterol-7α-hydroxylase is increased, HMG-CoA reductase significantly inhibited. Insulin treatment of the diabetic animal results in normalized values of HMG-CoA reductase whilst cholesterol-7α-hydroxylase is nearly completely suppressed. The rate-limiting enzymes of cholesterol turnover are peripherally regulated by their products via a negative feedback. In contrast, hormones may have synergistic or opposite effects; thus they may represent means of higher regulation. All regulative possibilities discussed (except hypophysectomy) do modify the circadian rhythms. This cannot be demonstrated after hypophysectomy. After hypophysectomy circadian rhythms are not detectable any more. To get valid data about biochemical or pharmacological effects on these enzymes the circadian variations have to be considered by measuring at different times of day (e.g. fat diet); for only the area of enzyme activity and time of day is proportional to the metabolism of a substrate.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00340534
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  • 10
    Digitale Medien
    Digitale Medien
    Einfluß von Insulin, Glukose und anderen Monosacchariden auf Plättchenfunktionen (1976)
    Springer
    Journal of molecular medicine 54 (1976), S. 1137-1141 
    Details
    ISSN: 1432-1440
    Schlagwort(e): Platelet Function ; Platelet Metabolism ; Insulin ; Glucose ; Plättchenfunktion ; Plättchenstoffwechsel ; Insulin ; Glukose
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die Wirkung von Insulin, Glukose, Xylose, Galaktose, Fruktose und Sorbitol auf den Plättchenaggregationstest nach Breddin, die ADP- bzw. Kollagen-induzierte Aggregation und Plättchenfaktor-4-Freisetzung sowie auf die Retraktion wurde in vitro untersucht. Die gemeinsame Inkubation plättchenreichen Plasmas mit Insulin und Glukose zeigt einen ausgeprägten Hemmeffekt auf die durch ADP oder Kollagen ausgelöste Plättchenaggregation und Freisetzungsreaktion. Insulin und Glukose allein hatten nur in höheren Konzentrationen einen Einfluß auf die Plättchenfunktion, der das Ausmaß einer Kombination nicht erreichte. Fruktose, Xylose und Sorbitol wiesen keine wesentlichen Hemmeffekte auf. Der Retraktionsgrad zeigte im Gegensatz zur verhinderten Aggregation eine Verbesserung. Ein Crabtree-Effekt wird als ursächlicher Mechanismus für die gehemmte Plättchenfunktion diskutiert.
    Notizen: Summary In vitro investigations were carried out on the action of insulin, glucose, xylose, galactose, fructose and sorbitol on the platelet aggregation test according to Breddin, on the ADP- and collagen-induced aggregation and the release of platelet factor 4 as well as on the retraction. When incubating platelet-rich plasma with insulin and glucose simultaneously, a marked inhibition of the ADP- or collagen-induced platelet aggregation and release reaction results. Insulin as well as glucose impaired the platelet function only at high concentrations, this inhibition however did not reach that of a combination of both. Fructose, xylose and sorbitol exerted no significant inhibitory effects. In contrast to the prevented aggregation, the retraction was enhanced. As the causal mechanism for the inhibition of the platelet function the Crabtree effect is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01469258
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  • 11
    Digitale Medien
    Digitale Medien
    Der Stoffwechsel bei vollständigem Fasten. Unterschiedliches Verhalten bei Männern und Frauen sowie bei Normalpersonen und Adipösen (1976)
    Springer
    Journal of molecular medicine 54 (1976), S. 527-533 
    Details
    ISSN: 1432-1440
    Schlagwort(e): Total fast ; Blood sugar ; Free fatty acids ; Ketone bodies ; Insulin ; Glucagon ; Growth hormone ; Vollständiges Fasten ; Blutzucker ; Freie Fettsäuren ; Ketonkörper ; Insulin ; Glucagon ; Wachstumshormon
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Bei 24 idealgewichtigen und 24 adipösen Personen beiderlei Geschlechts wurden zirkulierende Substrate (Blutzucker, freie Fettsäuren, Ketonkörper) und Hormone (Insulin, Wachstumshormon, Pankreasglukagon) während sechstägigem Fasten bestimmt. Der Blutzucker sank bei Normalpersonen unter Nulldiät auf tiefere Werte als bei Adipösen. Der Konzentrationsanstieg der freien Fettsäuren und Ketonkörper erfolgte bei Normalgewichtigen rascher als bei Fettsüchtigen und bei Frauen rascher als bei Männern. Das Plasmainsulin fiel bei Adipösen stärker ab als bei Normalpersonen. Alle untersuchten Gruppen wiesen nach 1–3 Fastentagen einen signifikanten Anstieg des Pankreasglukagons auf, dieser erfolgte jedoch bei normalgewichtigen Frauen rascher als bei Männern. Wachstumshormon (GH) stieg bei normalgewichtigen Männern unter Nulldiät signifikant an, bei adipösen Männern jedoch nicht. Bei z.T. auffallend hohen Nüchternwerten zeigten normalgewichtige Frauen keinen signifikanten GH-Anstieg, jedoch signifikant höhere GH-Konzentrationen als adipöse Frauen nach 1–6 Fastentagen. Ausgehend von den allen untersuchten Gruppen gemeinsamen Stoffwechselveränderungen bei Nulldiät werden die diesbezüglichen Unterschiede zwischen männlichen und weiblichen sowie zwischen normalgesichtigen und adipösen Personen diskutiert.
    Notizen: Summary In 24 normal and 24 obese subjects of both sexes circulating substrates (blood sugar, free fatty acids, ketone bodies) and hormones (insulin, growth hormone, pancreatic glucagon) were determined during 6 days of total fast. In normals the blood sugar fell to lower levels than in the obese. Plasma free fatty acids and ketone concentrations rose faster in normal than in obese subjects, and faster in females than in males. Plasma insulin concentrations declined to a greater extent in obese than in normal subjects. In all groups studied a significant increase of the pancreatic glucagon level within 1–3 days of fasting was observed, however, its rise occurred faster in normal females than in males. Growth hormone (GH) rose significantly in normal males but not in obese males. Following high overnight fasting values in some normal females showed no significant increase in GH levels but significantly higher GH values than obese females after 1–6 days of fasting. After summarizing starvation-induced metabolic changes common to all study groups the respective differences found between males and females and between normal and obese subjects are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01468974
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  • 12
    Digitale Medien
    Digitale Medien
    Vergleichende Untersuchungen über die Wirkung von Anticholinergika auf die basale und die durch Pentagastrin und Hypoglykämie stimulierte Magensekretion (1976)
    Springer
    Journal of molecular medicine 54 (1976), S. 485-492 
    Details
    ISSN: 1432-1440
    Schlagwort(e): Gastric secretion ; Pentagastrin ; Insulin ; Anticholinergics ; Oxacepam ; Magensekretion ; Pentagastrin ; Insulin ; Anticholinergika ; Oxacepam
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die Wirkung von Ipratropiumbromid und Propanthelinbromid per os auf die basale und auf die durch Pentagastrin und Insulin-Hypoglykämie stimulierte Magensekretion wurde im intraindividuellen Vergleich im Doppelblindverfahren untersucht. Die Dosis und die Wirkungszeit wurden variiert. Zusätzlich wurde die Anticholinergikawirkung mit der von Oxacepam auf die basale und auf die durch Pentagastrin stimulierte Magensekretion verglichen. Ipratropiumbromid hat einen stärker inhibitorischen Effekt auf die basale, Pentagastrin und Hypoglykämie stimulierte Sekretion als Propanthelinbromid. Das Wirkungsmaximum auf die basale Sekretion tritt erst nach 450 min ein, während die Wirkung auf die durch Pentagastrin stimulierte Sekretion eine kurzzeitigere ist. Die Wirkung konnte nur bei einer Anticholinergikadosis von 30 mg beobachtet werden. Oxacepam scheint eher einen steigernden Effekt auf die durch Pentagastrin stimulierte Magensekretion zu besitzen, der durch Ipratropiumbromid vollständig kompensiert werden kann. Eine Kombination Ipratropiumbromid+Oxacepam hat gegenüber Ipratropiumbromid allein keine stärkere Wirkung. Aufgrund der Ergebnisse wird ein Angriffspunkt für Anticholinergika direkt an der Belegzelle diskutiert.
    Notizen: Summary The effect of orally administered ipratropiumbromide and propanthelinbromide on the basic gastric secretion as well as on the gastric secretion stimulated by pentagastrin or hypoglycemia due to application of insulin was tested intraindividually in a double blind comparative study. Drug dosage and time after the drug effect was measured varied. In addition the anticholinergic effect of ipratropiumbromide on the basic as well as on the gastric secretion stimulated by pentagastrin was compared to that of oxacepam. The inhibitory effect of ipratropiumbromide on the basic gastric secretion as well as on the secretion stimulated by pentagastrin and hypoglycemia is more pronounced than that of propanthelinbromid. The effect on the basic secretion reached its peak 450 min after drug application whereas the maximal effect on pentagastrin stimulated secretion showed earlier. The effect described was only seen with a dose of the anticholinergic drug of at least 30 mg. A combination of ipratropiumbromide+oxacepam has no effect stronger than ipratropiumbromide alone. On the contrary, it rather seems to have an augmentative effect on pentagastrin stimulated gastric secretion that may be compensated completely by ipratropiumbromide. On the basis of these results a direct influence of anticholinergic substances on the parietal cell is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01469050
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  • 13
    Digitale Medien
    Digitale Medien
    Glucose uptake by normal human breast tissue in organ culture (1976)
    Springer
    Cell & tissue research 171 (1976), S. 535-541 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Breast ; Glucose ; Insulin ; Organ culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Résumé L'auteur a réalisé des cultures à long terme de tissu mammaire normal. Les explants ont été maintenus dans un milieu synthétique de base et comparés à d'autres fragments cultivés dans un milieu enrichi. La consommation quotidienne moyenne de glucose par explant a été mesurée dans six conditions différentes. Les résultats montrent une corrélation nette entre la consommation de glucose et sa concentration initiale dans le milieu de culture. D'autre part, l'adjonction d'insuline n'affecte pas de façon significative la consommation de glucose in vitro mais influence nettement l'activité mitotique. Ces observations confirment le rôle de l'Insuline sur la synthèse d'A.D.N. bien plus que sur le métabolisme du glucose par des explants de glande mammaire humaine normale.
    Notizen: Summary Normal human breast tissue explants were cultured in a synthetic basic medium with and without additives. The mean daily glucose uptake per explant was measured under six basic conditions. Our results show that glucose uptake is strongly related to the glucose concentration of the medium. On the other hand insulin does not affect significantly glucose uptake in vitro, but does enhance mitotic activity. These findings support a role for insulin in promoting D.N.A. synthesis rather than in controlling glucose metabolism of human mammary tissue in vitro.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00220244
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  • 14
    Digitale Medien
    Digitale Medien
    Insulin-, glucagon-, and somatostatin-immunoreactive endocrine cells in the equine pancreas (1976)
    Springer
    Cell & tissue research 172 (1976), S. 447-454 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Pancreas ; Horse ; Immunohistochemistry ; Insulin ; Glucagon ; Somatostatin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Equine pancreas was investigated with immunohistochemical methods to study the distribution of endocrine cells immunoreactive to antiinsulin, anti-glucagon, and anti-somatostatin. A-cells demonstrable by antiglucagon are located in the center of Langerhans islets and frequently in the duct epithelium. Few A-cells are seen associated to acini. Anti-insulin reactive B-cells form a large zone around the center of the Langerhans islets in which some B-cells lie between exocrine cells and others, although few, are located in the duct epithelium. D-cells stained with anti-somatostatin serum form a discontinuous outermost zone around the Langerhans islets. In some islets the D-cells are also observed among the B-cells or between the border of A- and B-cells. Single D-cells are seen in the duct epithelium or between acinar cells. In younger horses, endocrine cells are more frequently associated in bulges of the duct system. The histotopographic relation between these endocrine cell types is discussed with respect to its functional significance.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00220331
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  • 15
    Digitale Medien
    Digitale Medien
    The anatomy of the adult uropodid Fuscouropoda agitans (Arachnida; Acari), with comparative observations on other Acari (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 19-58 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: A thin, compressible, lateral suture and ventral plate overlap permit limited movement of the thick and rigid dorsal and ventral plates of Fuscouropoda agitans. Seven pairs of large dermal glands debouch onto the surface. Trochanteral rotation permits defensive leg adpresion and an insectan type of ambulation. The complex hypopharynx-pedipalpal-coxae has a buccal and cheliceral cavity separated by an atriculated epipharynx. The pharynx is Y-shaped in cross section. Extensive paired salivary glands lie above the very long and dexterous 3-segmented chelicerae, and a large pair of coxal glands debouch on coxae 1. From four blunt-ended tracheae, bundles of unbranching tracheoles extend in specific tracts to all organs. The ventriculus is small with three pairs of large caeca; a tightly packed single layer of digestive cells individually enlarged to absorb-phagocytize and digest the food. A typical mesostigmatid excretory tube is present. A typical acarine synganglion is present; mixed nerves have a basal swelling. A postulated neurosecretory organ arises from the pedipalpal nerve. The oocytes enlarge within funicular stalks from the walls of the small median ovary. A large spermatophore is stored in the seminal vesicle; fertilization occurs during oviposition. A tension hinge partially opens both male and female genital plates; closure effected by muscles acting on very long genital plate apodemes. Within sequentially produced spermatogonial cysts of the testes, meiosis is completely synchronous. A large, multilobed male accessory gland produces a large volume of seminal fluid; a mixture of at least four secretions. The origins and msertions of the body wall, genital organ, digestive tract, mouthpart and leg muscles are listed and illustrated. A comparison of anactinotrichid and actinotrichid mites indicates fundamental and consistent morphological differences in aspects of the cuticle, leg articulations, digestive system, excretory system, reproductive system and coxal glands.
    Zusätzliches Material: 21 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500103
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  • 16
    Digitale Medien
    Digitale Medien
    Development of butterfly scales. II. Struts, lattices and surface tension (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 279-297 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: An investigation of the structure of the iridescent scales of the green hairstreak, Callophrys rubi, reveals an internal lattice which is probably cubic close-packed in form. We present a model which explains the formation of the lattice in terms of packing of spheres and surface tension forces and generalize these results to internal structures in other Lepidopteran scales.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500202
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  • 17
    Digitale Medien
    Digitale Medien
    Labellar taste organs of Drosophila melanogasterWe wish to acknowledge with appreciation the excellent assistance of Mrs. R. Timberg with the transmission-electronmicroscope preparation and of Mr. T. Arad with the scanning-electron-microscope preparation.Parts of this study were supported by the Israel Commission for Basic Research. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 327-341 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: There are 36 to 42 taste bristles on each half of the labellum of Drosophila melanogaster; most of them are two-pronged with a pouch between them. Some end bluntly with a pore at the tip.Each taste-bristle has two lumina: one is circular, the other crescent-like in cross section. In most bristles four dendrites of chemoreceptor neurons run along the circular lumen. In five to seven taste-bristles only two chemoreceptor neurons are found. A mechanoreceptor neuron sends a dendrite to the base of each taste-bristle.The dendrites are surrounded by four concentrically-arranged sheath cells. The inner cell secretes the cuticular sheath; cells II and III are presumably two trichogens, one secreting the bristle material around the circular lumen, the other around the crescent-like lumen. Cell IV, especially rich in bundles of microtubules, secretes the cuticle of the socket, and corresponds to the tormogen. The neurons have the typical structure found in insect sensilla. In many sensilla one neuron is less electron-dense than the others and may be the water-sensor.On the medial side of the labellum between the pseudotracheae are rows of taste pegs covered by folds. In each peg one chemoreceptor and one mechanoreceptor are found.The number of axons in each labial nerve agrees with the total number of dendrites in all taste organs of each lobe.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500206
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  • 18
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500301
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  • 19
    Digitale Medien
    Digitale Medien
    Blood vascular system of the sea cucumber, Stichopus moebii (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 423-451 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Stichopus moebii, a sea cucumber, has a closed circulatory system which is unique in its degree of development for the phylum Echinodermata. The gross anatomy, histology and fine structure of the system were studied. Blood vessels consist of a coelomic surface of ciliated epithelium, a layer of muscle and nerve cells, followed by connective tissue and luminal lining of endothelium. Basically the blood vascular system consists of two major vessels running parallel to the gut: the dorsal vessel pumps colorless blood via the vessels within the walls of the intestine into the ventral vessel. There are two specialized areas of the circulation: (1) At the upper small intestine 120 to 150 muscular single-chambered hearts pump blood from the dorsal vessel into a series of intestinal plates. (2) At the lower region of the small intestine the vasculature is associated with the left respiratory tree. Blood passing from the dorsal pulmonary vessel can take two routes to the gut, it either passes through myriads of minute respiratory shunt vessels entangled with the respiratory tree or it passes through a unique follicle network consisting of tiny channels periodically dilated into chambers filled with iron deposits, necrotic cells and developing coelomocytes.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500211
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  • 20
    Digitale Medien
    Digitale Medien
    Sensory innervation in the rim of the octopus sucker (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 639-679 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Anatomical components of afferent innervation in the rim of the octopus sucker are described. In the sensory epithelium under the smooth cuticle two associated ciliated receptor cell-types (presumably chemosensitive) occur in clusters. A third ciliated receptor cell-type under the toothed cuticle may be a mechanoreceptor. A non-ciliated receptor cell-type of unknown function, under the toothed cuticle, is characterized by a microvillus-lined apical canal containing dense granular material. The axons of the latter two receptors go directly into large nerve tracts which nm through the infundibular muscle and on to the ganglion of the sucker. The axons of the first cell-types terminate on interneurons either in the base of the epithelium or below the epithelium. All the interneurons of the basal region of the epithelium migrate centripetally and develop into encapsulated interneurons. Within the epithelium, fine fibers provide collateral contact among cluster receptors. Collateral interaction among basal and encapsulated interneurons occur in the infundibular plexus. The microanatomy of the rim of the sucker suggests that chemosensory cues are funneled into the interneurons where they are concentrated into integrated signals, while other sensory input is probably sent directly to the ganglia of the sucker and/or arm.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500304
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  • 21
    Digitale Medien
    Digitale Medien
    Fine structure of the pyloric region and Malpighian papillae of protura (Insecta Apterygota) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 727-761 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The pyloric region of Eosentomon and Acerentomon (Insecta, Protura) is described. In both species the posterior cells of the midgut carry short microvilli. Beneath the epithelial cells there is a muscular pyloric sphincter for closing the intestinal lumen. Behind the sphincter is a wide pyloric chamber lined by cells with very long microvilli which point anteriorly toward the midgut. These cells regulate the passage of the intestinal contents into the hindgut. Secretions from the Malpighian papillae are emitted into the gut at this level. In Eosentomon three regions (R1, R2 and R3) are visible in the Malpighian papillae, whereas in Acerentomon region R1 is lacking. The R1 region contains secretory cells with elaborate glycoprotein-containing granules. The R2 region is composed of cells somewhat resembling the secretory cells of Malpighian tubules of insects. Presumably R1 and R2 cells emit secretions into the central cavity of each papilla. Cells of R3 form a duct for the secretion. It is suggested that the R2 region represents a basic excretory region, common to Protura, whereas the R1 region, in Eosentomon, may be a specialized area performing supplementary excretory functions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500307
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  • 22
    Digitale Medien
    Digitale Medien
    Light and electron microscopy of laser microirradiated nucleoli and nucleoplasm in tissue culture cells (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 785-803 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: This manuscript describes in precise detail the ultrastructural alterations produced as a result of laser microirradiation of nucleoli and nucleoplasm of tissue culture cells. Because of the general difficulty of single cell recovery, flat embedding, and serial sectioning, very few studies have ever been conducted on microbeam irradiated cells; yet the use of the microbeam technique has become widespread in functional studies of the nucleus. The results presented here demonstrate two classes of lesion material: small spherical electron dense bodies 0.05-0.02 μm in diameter and a larger, more irregular electron dense material up to 1 μm in length. The occurrence of these different types of lesion materials is described in control irradiated nucleoli and nucleoplasm, irradiated nucleoli and nucleoplasm in quinacrine treated cells, irradiated nucleoli and nucleoplasm in actinomycin D treated cells, and irradiated nucleoli and nucleoplasm in combined actinomycin D and quinacrine treated cells. In all the cells in which actinomycin D was employed, nucleoli were selectively irradiated in either their granular or fibrillar zones. The results of the ultrastructural studies are discussed in light of earlier functional studies.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500402
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  • 23
    Digitale Medien
    Digitale Medien
    Function of the digastric muscle in carnivores (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 843-859 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The general form and adaptation of the digastric muscle in carnivores are reviewed and discussed. The digastric muscle differs from the general plan in certain aquatic carnivores and felids. In the pertinent aquatic species the muscle is enlarged. The observations suggest that the enlargement is an adaptation for rapidly opening the jaws against the resistance of water. In felids, the insertion of the muscle is much farther forward than in most other carnivores. The observations suggest that the development of short jaws in felids necessitated a compensatory anterior relocation of the digastric insertion in order to preserve the ability to achieve a large gape.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500405
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  • 24
    Digitale Medien
    Digitale Medien
    Integumental organs of unknown function on chelipeds of deep-sea crabs, genus Hypsophrys (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 889-899 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Homolid crabs (Hypsophrys) from water deeper than 700 m in the Straits of Florida and Arabian Sea have smooth darkened oval spots contrasting with the surrounding roughened integument on inner and outer surfaces of each pincer at the base of the fixed finger. Cuticle is thinner over these spots than over surrounaing tissues. Beneath each spot is an organ composed of two markedly contrasting layers of tissue: (1) an outer, densely staining layer of tightly packed tubules, relatively straight and perpendicular to the overlying surface proximally but progressively convoluted and narrowed distally, finally ending blindly in association with the overlying thinned cuticle; (2) an inner layer of relatively large, eosinophilic, irregular cells with dark nuclei also trending at a right angle to the integument and bulging into the hemal sinus of the hand but separated from it by an epidermal lining. Droplets secreted from the inner layer apparently move into and along the tubules. Similar organs are known in no other crabs. The function is unknown but the structure suggests that they may be photophores.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500407
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  • 25
    Digitale Medien
    Digitale Medien
    Ultrastructure of the blowfly chemoreceptor sensillum (Phormia regina) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 763-783 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The ultrastructure of a well studied insect chemosensory unit is presented in this report. Two separate lumina are present in this chemosensory unit, the trichogen and sensillar lumina. The fluid within the trichogen lumen exclusively bathes the dendritic terminals, and may be involved with the reception and/or modulation of environmental stimuli. Cytoplasmic extensions of the trichogen cell which line the trichogen lumen may be involved in the production of the cuticular sheath. The sensillar lumen is bordered by the tormogen and a sleeve cell, and is continuous with the unoccupied channel of the setal shaft. Functions for the various cellular components of the blowfly chemoreceptor sensillum are offered.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500308
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  • 26
    Digitale Medien
    Digitale Medien
    A comparative study of the ultrastructure and mineralogy of calcified land snail eggs (Pulmonata: Stylommatophora)From a dissertation submitted in partial fulfillment of the requirements for the Ph.D. degree, Department of Zoology, University of Michigan, Ann Arbor. Supported in part by an NSF traineeship through the Department of Zoology. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 861-887 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: This study indicates that eggs containing calcium carbonate crystals occur in at least 36 of the 65 known families of the land snails (class Gastropoda: order Stylommatophora). Eggs from 22 of these families were available for examination. The x-ray diffraction data, available for the first time for 21 of these families, shows that these egg shells are all made of calcite only, or of a combination of calcite with smaller amounts of aragonite. All of the snail (body) shells examined were made of aragonite only. This is the first ultrastructural investigation of these egg shells, and it indicates that the eggs exhibit enough structural diversity to allow identification of parental animals to genus, and often to species level solely on the basis of egg shell ultrastructure.All of the calcified eggs may be divided into two groups: (1) partly calcified, with discrete crystals of CaCo3 dispersed in the jelly layer, and (2) heavily calcified, with a hard, brittle egg shell made of fused crystals of CaCO3 much like an avian egg. Both types of calcified eggs occur in oviparous as well as in ovoviviparous snails. Because of the wide distribution of calcified eggs in the Stylommatophora, and because of the occurrence of heavily calcified eggs in ancient families such as Partulidae, Endodontidae, and Zonitidae, the calcified egg is viewed as a primitive land snail trait associated with terrestrial adaptation. The function of the calcified egg shell, in addition to mechanical support of egg contents, is to supply the developing embryo with enough calcium to form the embryonic shell by the time of hatching.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500406
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  • 27
    Digitale Medien
    Digitale Medien
    A brachial glycogen body in the spinal cord of the domestic chicken (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 23-31 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: When cervical segments 14 to 15 of the chicken spinal cord are cut transversely and studied by routine histological and histochemical methods, an onion-shaped region, filled with thread-like fibers, if seen to surround the ependymal cells of the central canal and to be bounded laterally by the neural elements of the spinal gray matter. This area is negative for succinic dehydrogenase, beta-hydroxybutyrate dehydrogenase and cholinesterase activity, but very strongly periodic acid-Schiff positive. Diastase controls show the positive material to be glycogen. Parasagittal sections through this cervical region and into the upper thoracic cord, show the glycogen-rich region to extend longitudinally throughout the region. Because of its location and histochemical characterization, which, He similar to that of the ventral portion of the glycogen body, the term brachial glycogen budy is proposed for this structure.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480103
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  • 28
    Digitale Medien
    Digitale Medien
    Structure of anterior dorsal ventricular ridge in snakes (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 1-21 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Anterior dorsal ventricular ridge (ADVR) is a major subcortical; telencephalic nucleus in snakes, Its structure was studied in Nissl, Golgi, and electron microscopic lrerarations in several species of snakes. Neurons in ADVR form a homogeneous population. They have large nuclei, scattered cisternae of rough endoplasmic reticulum in their cytoplasm, and bear dendrites from all portions of their somata. The dendrites have a moderate covering of pedunculated spines. Clusters of two to five cells with touching somata can be seen in Nissl, Golgi, and electron microscopic preparations. The area of apposition may contain a series of specialized junctions which resemble gap junctions. Three populations of axons can be identified in rapid Golgi preparations of snake ADVR. Type 1 axons course from the lateral forebrain bundle and bear small varicosities about 1 μ long. Type 2 axons arise from ADVR neurons and bear large varicosities about 5 μ. long. The origin of the very thin type 3 axons is not known; they bear small varicosities about 1 μ. long. The majority of axon terminals in ADVR are small (1 μ. to 2 μ long), contain round synaptic vesicles, and form asymmetric active zones. This type of axon terminates on dendritic spines and shafts and on somata. A small percentage of terminals are large, 5 μ in length, contain round synaptic vesicles, and form asymmetric active zones. This type of axon terminates only on dendritic spines. A small percentage of terminals are small, contain pleomorphic synaptic vesicles, and form symmetric active zones. This type of axon terminates on dendritic shafts and on somata.
    Zusätzliches Material: 15 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480102
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  • 29
    Digitale Medien
    Digitale Medien
    The development and replacement of teeth in viviparous caecilians (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 33-63 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Tooth development and replacement in fetal and adult viviparous caecilians (Amphibia: Gymnophiona) are described and analyzed according to current theories of tooth succession. The fetal dentition differs from that of the adult in morphology, position, and function. Teeth are used by fetuses to scrape the oviducal epithelium, thus stimulating the secretion of a nutrient substance. Fetal dentitions vary in morphology and position in different species. The ontogeny of teeth of several species is described and the patterns of addition of loci and of replacement are analyzed, Loci are added both posteriorly along the jaw and between existing loci as the jaw grows prior to ossification; subsequently addition is restricted to the posterior part of the jaw. Tooth replacement is alternate. The several rows and patches of teeth are the result of retention of replacement series on the dentigerous elements. Tooth development and replacement in a series of juveniles and adults of different sizes in a single species are also considered. Post-fetal patterns of development and replacement are similar to those seen in larvae and adults of oviparous species. Variation in numbers of teeth and proportions of teeth at particular stages occurs ontogenetically and among individuals of the same size, though proportions occur in a similar pattern throughout the series. The general pattern of tooth replacement in fetuses and adults can be explained by either Edmund's Zahnreihen theory or by Osborn's Tooth Family theory, but replacement in fetal tooth patches and the fetal-adult dentitional transition are explained by neither.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480104
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  • 30
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480201
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  • 31
    Digitale Medien
    Digitale Medien
    Electron microscope studies of spermatogenesis in Branchiobdella pentodonta whitman (Annelida, oligochaeta) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 65-87 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: In Brallchiobdella pentodonta Whitman meiosis begins in follicles containing 16 spermatogonia. In each follicle the spermatogonia are connected by cytoplasmic bridges to a central anuclear cytoplasmic mass or cytophorus. They develop synchronously. Synaptonemal complexes are present in the primary spermatocytes. Spermatids contain a large globoid paranuclear body consisting of an acrosomal granule and coiled tubules which evidently receive the contents of the acrosomal granule and are considered the acrosome carrier. The spermatids separate from the cytophorus only when differentiation is completed.The ripe spermatozoon is relatively long. It has anteriorly the coiled tubules, followed by the nucleus, the mitochondrial sphere and the distal centriole from which the flagellum originates, A coiled ribbon-like structure encloses the flagellum along its entire length while a manchette of microtubules surrounds all the other structures of the sperm.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480105
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  • 32
    Digitale Medien
    Digitale Medien
    The pectoral anatomy of selected ostariophysi I. The characiniformes (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 89-135 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The muscles and bones of the pectoral fin of Serrasalmus nattereri, the piranha, resemble those of generalized, lower teleosts with specializations related to a body shape adapted for high-speed carnivory; the pectoral fins being highly mobile with strong ligaments to the rays. The presence of two occipital nerves appears primitive, while the emergence of the subclavian artery within the branchial cavity, as in Gasteropelecus sternicla, appears specialized. The muscles and bones of the latter fish, a fresh-water flying fish, are specialized for self-propelled, aerial flight in the fusion of the right and left girdles greatly expanded for insertions of complex appendicular (flight) muscles, and in the consolidation of the rays and radials into one functional unit moving vertically in flight though contraction of vertical, massive ventral flight muscles. The bony pectoral anatomy of Electrophorus electricus, the electric eel, is specialized in having a mobile joint between the primary girdle and the cleithrum, the former being suspended vertically from the cleithrum by ligaments. The proximal radials and rays are very numerous and vertically aligned. The cleithrum is shaped to accommodate the extensive sternohyoid and pharyngocleithral muscles. The sheet-like appendicular muscles extend beyond the special joint and control its movement. The deeper muscles do not cross this joint. The arterial system is specialized in lacking a deep brachial artery.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480106
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  • 33
    Digitale Medien
    Digitale Medien
    Fine structure of the triturating devices in pumps of the food Aphelocheirus and typical naucoridae (heteroptera) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 1-31 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The cibarial food pumps of aquatic Heteroptera contain specialized epipharyngeal triturating devices. In the Naucoridae, striated bands and transverse plates triturate particles against the underlying hypopharynx. Anterior to them lie a pair of oblique folds which play an accessory role. The gross morphology of these devices is very similar in representatives of five genera of typical Naucoridae (Ambrysus, Pelocoris, Limnocoris, Cataractocoris, Cryphocricos) and differs from that of the atypical genus Aphelocheirus.The scanning electron microscope reveals additional differences between Aphelocheirus and the typical genera as well as variations, among the latter, which are not visible with the stereoscopic microscope. The oblique folds of the typical Naucoridae are well developed and contain processes for trapping particles; in three genera the region posterior to the folds is also modified. In Aphelocheirus only the latter region appears to trap particles, and the oblique folds are smooth and weakly developed. The striated bands of all genera bear ventral ridges arranged into transverse zones with precise patterns. The fourzoned bands of Aphelocheirus have a very different pattern than the two-zoned bands of the other genera. Among the latter, Cryphocricos has a simpler pattern of ridges than the other typical Naucoridae. The ventral surfaces of the transverse plates are highly modified in Aphelocheirus and less so in the other genera; those of Cryphocricos differ from those of the other Naucoridae.The fine structure of the cibarial epipharynx supports the views of some systematists that (1) Aphelocheirus should be placed in the monogeneric Family Aphelocheiridae rather than in the Naucoridae, (2) Cryphocricos represents a different subfamily than the other four typical Naucoridae, and (3) Cataractocoris belongs in the same subfamily as Ambrysus rather than with Cfyphocricos.
    Zusätzliches Material: 12 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490102
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  • 34
    Digitale Medien
    Digitale Medien
    Collagen deposition on a preformed grid (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 53-71 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Appearance of collagen fibrils in the cuticle was seen by electron microscopy to be preceded by fonnation of a finely filamentous matrix material. At first, the fine filaments of the matrix are unorganized. However, signs of orthogonal ordering soon appear in the most superficial portion of the cuticle, and subsequently appear more basally and closer to the underlying epidermis. Meanwhile, fibrils of different staining properties and identifiable as collagen begin to be deposited in the superficial portion of the cuticle, the same region which first showed organized fine filaments. Then, like the fine filaments before them, the collagen fibrils polymerize more basally. Collagen appears to polymerize on the preformed skeleton of fine filaments as though the fine filaments caused the collagen to assemble. Neither the polymerization nor ordering of collagen fibrils seems to require direct cellular intervention but occur first in that portion of the cuticle which is furthest away from the underlying epidermis. The fine filaments may be self ordering, extracellular macromolecules which in turn determine the polymerization of collagen fibrils.
    Zusätzliches Material: 11 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490104
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  • 35
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490201
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  • 36
    Digitale Medien
    Digitale Medien
    Genesis and structure of the so-called “balbiani body” or “yolk nucleus” in the oocyte of dugesia dorotocephala (turbellaria, tricladida) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 265-277 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Oogenesis of the fresh-water triclad Dugesia dorotocephala has been studied by electron microscopical methods, with particular regard to the genesis and composition of the so-called “Balbiani body.” Its origin is clearly recognizable in young oocytes where the few mitochondria present seem to gather at the level of the perinuclear ooplasm. Here they surround dense masses of finely granular, fibrillar material probably coming from the nucleus. During the previtelloge ic period, mitochondria rapidly increase in number while the dense masses progressively dissolve.In the vitellogenic oocytes the Balbiani body shows its final configuration: it appears as a large area (up to 15-20 pm in diameter) consisting of innumerable densely packed mitochondria, some smooth vesicles and free ribosomes. This aggregate of cytoplasmic organelles remains unmodified in the mature oocytes.The function of the “Balbiani body” of D. dorotocephala is as yet unclear; it can only be asserted that it is not correlated with yolk production in which the endoplasmic reticulum and the Golgi complex are involved.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490208
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  • 37
    Digitale Medien
    Digitale Medien
    The response of transplants of cultured fetal mouse ovaries in kidneys of ovariectomized adult mice (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 421-435 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Whole ovaries from 16-day fetal mice were cultured for 6 to 20 days and then transplanted to the kidneys of ovariectomized adult mice where they remained for one to four weeks. After three weeks in the host's kidneys, many follicles developed within the transplants and became vesiculated. Many of the oocytes within these follicles had formed the first metaphase spindle of meiosis and several had completed the first polar body. Host mice bearing transplants that contained vesiculated follicles showed uterine stimulation and keratinization of their vaginae. However, ovaries that had been in culture for more than ten days before transplantation showed a limited response to the gonadotropins and never matured sufficiently to stimulate the host's reproductive tract. No ovulations occurred in any of the transplants.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490309
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  • 38
    Digitale Medien
    Digitale Medien
    Further observations on the fine structure of the infracerebral gland in Nereis (Annelida; Polychaeta)  -  C2 and C3 cells; centripetal and centrifugal fibersSupported by Research Grant B/SR 9636, from the Science Research Council, U.K. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 1-17 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The infracerebral gland of Nereis is made up of three types of cells. C1 cells are hypertrophied pericapsular elements, whereas C2 and C3 cells have the morphological and cytological features of neurosecretory neurons. C2 and C3 cells give rise to centripetal “proximal processes” which extend into the brain through the midventral pocket formed by delamination of the brain capsule. Their “distal processes” terminate within the gland or its immediate vicinity. “Centrifugal fibers” arise from nerve cells located within the brain and appear to synapse upon the proximal processes of C2 cells in the region of the midventral pocket and in the ventral region of the brain. The cytology of C2 and C3 cells suggests that they are the source of distinct peptide hormones.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500102
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  • 39
    Digitale Medien
    Digitale Medien
    The effect of exercise on the growth of mitochondria and myofibrils in the flight muscles of the tsetse fly, Glossina morsitans (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 321-326 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Exercise affects the growth of the dorsal longitudinal flight muscles in the tsetse fly. Examination of electron micrographs of flight muscles taken from flies subjected to enforced exercise, “ormal” exercise and no exercise reveals that both mitochondrial and myofibrillar fractions of the muscles are stimulated to grow at a faster rate by enforced exercise but that the mitochondria respond more rapidly.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500205
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  • 40
    Digitale Medien
    Digitale Medien
    The cytology of the testaceous rhizopod Lesquereusia spiralis (Ehrenberg) Penard. I. Ultrastructure and shell formation (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 343-357 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Ultrastructure and shell formation in the testaceous ameba, Lesquereusia spiralis, were investigated with both scanning and transmission electron microscopy and X-ray microanalysis. The nucleus, surrounded by a fibrous lamina, contains multiple nucleoli. The cytoplasm, containing a well developed granular endoplasmic reticulum, also contains remnants of starch granules in stages of digestion. Spherical aggregates of ribosome-like particles may be seen. Golgi complexes seem to produce both a nonordered fibrous material and an electron dense vesicle. Only the latter appears to bleb off from the Golgi complex. X-ray microanalysis demonstration of silicon in Golgi vesicles and in some dense vesicles suggests that the fibrous component of the cisternae may take up and concentrate silica to form the electron-dense component of the vesicles. Membrane-bound siliceous crystals are often seen adjacent to the Golgi, suggesting either a Golgi origin or platelet formation in vesicles after release from the Golgi complex. Both electron-dense bodies and siliceous platelets are released from the cell by a process similar to apocrine secretion and may be seen outside the cell in route to the shell during shell morphogenesis. Shell development involves fusion of electron-dense bodies to form a matrix, positioning of siliceous platelets in this matrix parallel to the shell surface, and development of a system of matrix chambers. A particulate glycoconjugate is released to the shell surface upon rupture of the matrix chamber.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500207
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  • 41
    Digitale Medien
    Digitale Medien
    A stereological analysis of the ultrastructure of the lungs of wild mice living at low and high altitude (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 359-368 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Stereological analysis of the ultrastructural composition of the pulmonary alveolo-capillary region of mice living at sea level compared with that of the same species (Phyllotis darwini) genetically adapted to life at 4,660 m reveals a trend at high altitude towards a greater volume percentage of tissue components. On a weight-specific basis, non-circulating tissue occupies a significantly greater volume in high-altitude mice, but air space and capillary contents are not correspondingly greater. Since the arithmetic mean thickness of the tissue layers and of the air-blood barrier are the same in the two altitudinal groups, the average alveolus must have a smaller volume in the high-altitude mice.Epithelial, endothelial, and erythrocyte surface areas per gram body weight are significantly greater in the high-altitude mice.Nuclear counts indicate that the larger lungs of mice adapted to high altitude are due to larger Pneumocyte I and II and endothelial cells rather than to an increase in the number of these cells. Hematocrits measured within the pulmonary capillaries in the two altitudinal groups were equal.An heretofore unrecognized feature of possible adaptive value is the surface/volume ratio of erythrocytes, which is similar for erythrocytes in alveolar space of mice at low and high altitudes but within lung capillaries is 14.7% greater at high altitude.
    Zusätzliches Material: 4 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500208
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  • 42
    Digitale Medien
    Digitale Medien
    The neck region of the spermatozoon of Discus rotundatus (Müller) (Pulmonata, Stylommatophora) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 299-305 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The neck region of the mature spermatozoon of Discus rotundatus is described. No evidence for a centriole or centriolar derivative is obtained. Nine striated coarse fibres and the two central fibres of the axoneme extend into the base of the implantation fossa. The axonemal doublet system is disrupted in the neck region. There are two fibrous accessory structures located between the central doublet and the striated coarse fibres.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500203
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  • 43
    Digitale Medien
    Digitale Medien
    Early chick neuroretinal responses following direct exposure to methotrexate (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 307-319 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Explants of 4.5-day-old chick embryonic neuroretinas with mesenchyme were exposed to Methotrexate (MTX) in medium 199 with embryo extract. Proliferative responses of the cultured neuroretinas were followed radioautographically by administration of 3H-thymidine to the cultures. The DNA synthetic, mitotic and pyknotic responses of the ventricular cells of the neuroretina were followed over a 16-hour period. The responses observed suggested that MTX caused a synchronization of the ventricular cells in the pre-mitotic phases with no direct inhibition of mitosis. Furthermore, prolonged exposure to MTX resulted in the accumulation of labeled pyknotic cells, indicating a decline in the regenerative capacity of the proliferative ventricular cells.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500204
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  • 44
    Digitale Medien
    Digitale Medien
    Stage specific larval, pupal, and adult cuticles in the tracheal system of Sarcophaga bullata (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 369-397 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Successive tracheal cuticles of the dorsal longitudinal trunks are studied with the electron microscope. Minor differences seen at the light microscope level are seen as major qualitative and quantitative ones at the ultrastructural level. The larval and pupal cuticles are secreted by similar epithelial cells; these possess large polytene chromosomes. Cell division and possibly cell replacement occur prior to adult cuticle secretion. The findings are discussed in terms of cell specificity, intra- and inter-cellular pattern formation. This simple epithelium, the individual cells of which are capable of producing different cuticles, is interesting since the system is also shown to be responsive to hormone application.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500209
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  • 45
    Digitale Medien
    Digitale Medien
    Effects of incubation temperatures on sexual differentiation in the turtle, Chelydra serpentina (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 453-461 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Eggs of the common snapping turtle, Chelydra serpentina, were incubated at constant temperatures ranging from 20°C to 30°C, At hatching, the oviducts were absent or incomplete in males; the testes were differentiated. In females at hatching, the oviduct was intact hut in some cases the gonad retained bisexual characteristics. Three months after hatching, the ovary was differentiated and contained follicles. Eggs incubated at 20°C and at 30°C developed into females in 100% of the cases. At 26°C, 99% of the individuals were males; at 24°C, 100% were males. More males than females developed at incubation temperatures of 22°C and 28°C.
    Zusätzliches Material: 3 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500212
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  • 46
    Digitale Medien
    Digitale Medien
    Studies on the asexual reproduction in the polystyelid ascidian, Polyzoa vesiculiphora TokiokaContributions from the Shimoda Marine Biological Station, No. 300.The cost of this research has been partly defrayed from the Scientific Research Expenditures of the Department of Education of Japan and the Asahi Press. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 607-621 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: New blastozooids of Polyzoa vesiculiphora, the polysytelid ascidian are produced by pallial budding of three types depending on the method of “isolated bud” formation; stolonic, planktonic and intermediate types. Differences among each type of bud are attributed to behavior of test-vessels composing a part of the bud. Isolated buds produced by each type are essentially equal in terms of their internal structures and their subsequent fate, and develop independently of their parent zooids. New test-vessels originate directly from the epidermis of a “prefunctional zooid,” while the test-vessels derived from the parent zooid finally disintegrate. The new test-vessels extended with branching under the ventral side of a “functional zooid,” ascend to the lateral side of it and participate in bud formation. Budding regions exist in three dimensions on the lateral wall of the mantle of the functional zooid, especially the right posterior part. During the life cycle of one functional zooid, the stolonic type buds appear at early and/or aged stages. Appearances of the stolonic type buds in early stages tend to repress those of the planktonic types. The number of planktonic type buds formed on a functional zooid at the same time is many more than that of the stolonic type. Such budding features are discussed from the viewpoint of behavior of the test-vessel system.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500302
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  • 47
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500401
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  • 48
    Digitale Medien
    Digitale Medien
    The anatomy of the parotoid gland in Bufonidae with some histochemical findingsSupported in part by Grant N.I.H. GM 00459-15. II. Bufo alvarius (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 137-159 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The gross and microscopic anatomy of the venom producing parotoid glands of Bufo alvarius has been studied by light and electron microscopy. Histochemical reactions for the presence of venom constituents and of components in biochemical pathways in the synthesis and release of venom were performed. The gland is composed of numerous lobules. Each lobule is an individual unit with a lumen surrounded by a double cell layer. Microvilli of the outer layer interdigitate with microvilli of the inner layer. Cells of the outer layer resemble smooth muscle cells, are rich in adenosine triphosphatase and glucose6-phosphatase, and contain numerous pinocytotic vesicles, glycogen granules and various organelles, These organelles include “crystalloids” of what seem to be highly organized agranular reticulum. These outer layer cells probably function in some aspects of venom synthesis, active cellular transport and contraction in the discharge of the secretory product. The inner cell layer demonstrates a positive chromaffin reaction, contains steroid material, various organelles, some pinocytotic vesicles and glycogen granules, and appears devoid of a plasmalemma on its inner surface. This layer is probably involved in venom formation and release via an apocrine type of secretion.Bufo alvarius parotoid gland shows significant morphological and histochemical differences from that of B. marinus and more nearly resembles a typical steroid producing organ.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480202
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  • 49
    Digitale Medien
    Digitale Medien
    Cell division and tissue repair following localized damage to the mammalian lung (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 177-184 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Small local wounds on the surface of the mouse lung, produced by cauterization, healed by a typical reparative process involving c1 migration and increased cell division in alveolar and bronchial tissues. The local cell division response closely resembled the compensatory cell division response in the same organ which follows unilateral pnemnonectomy or unilateral collapse of the lung: initially there was an increase in the rate of DNA synthesis followed by an increased rate of entry into mitosis, both of these functions returning to normal levels within a few days. It is therefore suggested that both types of response are governed by a single regulatory mechanism. The results do not support the view that the rate of cell division is regulated by systemically-circulating mitotic control factors and it is proposed that changes in the cell division rate, both in the reparative and in the compensatory types of response, are determined by local alterations ill the concentration of regulatory metabolites.The magnitude of the cell division response was much greater in bronchial than in alveolar tissue. a result which is consistent with the view that new alveolar tissue may be produced by the proliferation and differentiation of bronchial cells.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480204
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  • 50
    Digitale Medien
    Digitale Medien
    Budding by Oozooids in the Polystyelid Ascidian Metandrocarpa Taylori Huntsman (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 161-176 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Larvae of the stolidobranch ascidian Metandrocarpa taylori molt a thin sheath upon settling, then metamorphose and radiate a larval complement of vascular ampullae upon the substrate. These ampullae thereafter regress, “rest” in a reduced condition for several weeks, and then regrow into the oozooids definitive array of vascular ampullae in accompaniment to the development of the oozooidal vascular nest of test-vessels. Pallial buds emerge some four months after the larva settles; the oozooid has by then grown to a length of at least 2 mm and its vascular nest is surrounded by at least 16 vascular ampullae. Oozooids bud one to five buds (mean, 2.6) in a rather short period of blastogenic vigor, then persist in the colony. Late buds are frequently aborted. Buds appear anywhere around the basal margin of the oozooid, but more often on the left than the right and more often posteriorly than anteriorly. As other studies have observed with blastozooids, this study notes an integration of budding and the disposition of the elements of the test-vessel system of oozooids. Buds emerge oriented tangentially to the parental basal margin at the bud-site, then often rotate to point their anterior ends away from the parent. No larvae metamorphosed into oozooids with situs inuersus uiscerurn, but in this study two oozooids extruded blastozooids showing this anomaly; these blastozooids budded reversed zooids in turn, so that entire clonal lines showed the anomaly.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480203
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  • 51
    Digitale Medien
    Digitale Medien
    Histological and histochemical comparisons of muscle spindles in three hind limb muscles of the guinea pigThis work was supported by USPHS Grants NS 10497, NS 62927 and NS 10423. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 185-191 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Guinea pig soleus, medial gastrocnemius and vastus lateralis muscles were compared for spindle density and distribution, number of intrafusal fibers per spindle and histochemical appearance of the axial bundle. A total of 326 spindles was used in the comparisons. Spindle density was over four times greater in the soleus than in either the medial gastrocnemius or vastus lateralis. In the soleus the spindles were distributed at random, but in the other two muscles no spindles were found in those fascicles in which fast-twitch glycolytic extrafusal fibers predominated. The average number of intrafusal fibers per spindle varied by less than 5% between the three kinds of muscles. About 80% of all spindles located had four intrafusal fibers, two of the nuclear bag type and two of the nuclear chain type. The histochemical appearance of the axial bundle was the same in each kind of muscle. Based on intensities of the myofibrillar adenosine triphosphatase reaction product at polar regions nuclear bag fibers were separable into two histochemical groups; nuclear chain fibers were of only one histochemical type.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480205
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  • 52
    Digitale Medien
    Digitale Medien
    Ultrastructure of the cement gland of Xenopus laevis (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 193-207 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: To establish a morphological baseline for experimental studies of differentiation using the cement gland as a model, the following observations are added to those on record. The elongated cells of Xenopus laevis cement glands have an internal organization displaying five distinct zones differing in structure and specialized function. The apical zone contains packed secretion vesicles apparently belonging to two different types. The transit zone appears to be devoid of major biosynthetic activity and contains secretion vesicles migrating toward the surface. The zone of biosynthesis is typically organized in concentric regions. The very elongated nucleus lies in the next zone. Finally, the storage zone is characterized by lipid droplets and yolk platelets.Only quantitative differences are observed between cells of young and mature cement glands. Though all cells have the same general organization they may probably be divided into two subtypes according to the structure of their cytoplasm. The epithelial cells surrounding the gland differ according to their position along lateral or basal borders.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480206
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  • 53
    Digitale Medien
    Digitale Medien
    The fine structure of the sperm of a holothurian and an ophiuroid (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 209-225 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The fine structure of the mature sperm of the holothurian, Cucumaria miniata, and the ophiuroid, Ophiopholis aculeata, is described with particular reference to their acrosomal and centriolar satellite complexes, and compared to the sperm of other echinoderms.In Cucumaria, the acrosome is in the form of a diffuse acrosomal vesicle. It is unusual in that it apparently lacks an acrosomal membrane. A membrane separating the acrosomal vesicle from the periacrosomal material may not be equivalent to a typical inner acrosomal membrane. In Ophiopholis, the acrosome is dense, with some internal substructure, and is enclosed by a complete acrosomal membrane. In both species, the acrosome is partially surrounded by an amorphous periacrosomal mass. There is a notable absence of a subacrosomal depression and associated structures as found in other echinoderm sperm.The centriolar satellite complex (CSC) is essentially identical in both species. A reconstruction of the CSC is presented. The CSC consists of nine satellites radiating angularly from the distal centriole, each bifurcating at a dense node before inserting on a marginal ring containing circumferential microtubules. The ring is probably a cytoskeletal element. Immediately below the satellites are nine Y-shaped connectives. connecting each of the axonemal alpha doublets to the flagellar membrane.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480207
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  • 54
    Digitale Medien
    Digitale Medien
    Fine structure of the dorsal bristle complex and pellicle of EuplotesThe research reported here was supported by a Developmental Biology Training Grant from the National Institute of Child Health and Human Development (HD.00152.04) to J. J. Ruffolo, NSF Grant GB.24901 to N. E. Williams, and NSF Grant GB 32408X to J. Frankel. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 469-487 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The fine structure of the dorsal bristle complex and pellicle of non-developing Euplotes eurystomus is described in detail by scanning and transmission electron microscopy. The bristle-pit unit is a highly differentiated complex of organelles. The bristle complex is composed of a pair of kinetosomes (basal bodies) joined by a connective. The anterior kinetosome bears the bristle cilium, which contains a polarized network of particles (“lasiosomes”). The posterior kinetosome bears a very short, knob-like “condylocilium,” and has an associated striated fiber. Accessory ribbons of microtubules are also associated with the kinetosome couplets. Parasomal sacs, a septum connecting the bristle cilium to the anterior wall of the pit, core granules of the kinetosomes, and large membranous ampules are described. The organization of the bristle complex bears many similarities to the somatic ciliature of other ciliates. The pellicle of Euplotes is composed of a continucus outer cell membrane subtended by membranous alveoli, which contain a “fibrous mat.” Two sheets of subpellicular microtubules (longitudinal and transverse) are located just beneath the alveoli. The “epiplasm” seen in some other ciliates is apparently absent in Euplotes. The texture of the cell surface is a pattern of folds or rugae composed of the outer cell membrane and the upper membrane of the alveolus. The pattern of rugae probably defines the “silverline-system” of light microscopy.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480405
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  • 55
    Digitale Medien
    Digitale Medien
    Cortical morphogenesis during the cell division cycle in Euplotes: An integrated study using light optical, scanning electron and transnlission electron microscopyThe research reported here was supported in part by a Developmental Biology Training Grant from the National Institute of Child Health and Human Development (HD-00152-04) to J. J. Ruffolo. NSF Grant GB-24901 to N. E. Williams, and NSF Grant GB-32408X to J. Frankel. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 489-527 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Hypotrichs are among the most complex ciliates in terms of morphology and development. To study the fine structure of cortical morphogenesis associated with cell division in Euplotes eurystomus, three different methods of observation were employed: light microscopy of protargol-stained specimens, scanning electron microscopy of cells prepared by critical point drying, and transmission electron microscopy of sectioned material. Observations on the stages of morphogenesis give much new information about cortical development, particularly about proliferation and aggregation of kinetosomes (basal bodies), ciliary outgrowth, the topography of morphogenesis, cirrus resorption, and growth of the pellicle. During the formation of new cirrus the process of kinetosome proliferation is atypical, i.e., groups of prokinetosomes are seen oriented at random and, in some cases, prokinetosomes apparently are formed at a distance from nearby young kinetosomes. That the new cirri develop in surface grooves, the grooves elongate into “tracks,” and (in some cases) grooves are partitioned into separate tracks suggests that the grooves play a role in the orderly migration of the new cirri on the cell surface. Conspicuous morphogcnctic changes in the cell surface involve local growth of the pellicle. The process of pellicle growth apparently involves two basic steps: (a) growth of the outer cell membrane to form “bare regions,” and (b) formation of alveoli in the bare regions. Alveolar sheets are formed by fusion of alveolus precursor particles. Cirrus resorption is sequential over several stages of development, and old cirri are resorbed as the new cirri impinge on them. As the old cirri regress, both in situ resorption and retraction of axonemes into the cytoplasm occur.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480406
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  • 56
    Digitale Medien
    Digitale Medien
    Collagenous and other organizations in mature annelid cuticle and epidermis (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 33-51 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The mature annelid cuticle contains orthogonally oriented collagen in a matrix capped superficially by a dense epicuticle with external corpuscles. The underlying epidermis is a simple columnar epithelium with two major cell types, mucous-secreting cells which secrete through channels in the cuticle to the exterior of the worm, and “supportive” cells which presumably produce and increase the cuticle by secreting into it.The structures of supportive cells, previously interpreted as specialized for establishing interfibrillar collagen order, are revealed by glutaraldehyde fixation as common cellular components without the qualities deemed useful to align collagen. Cell processes which penetrate and sometimes pass completely through the cuticle are not stable, not in geometric order, and lack cilia-like structure. Cilia, unlike the ubiquitous cellular processes, are highly restricted to regions of the epidermis with specialized functions. Cellular control, or other control, of collagen fibrillogenesis remains unestablished.
    Zusätzliches Material: 16 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490103
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  • 57
    Digitale Medien
    Digitale Medien
    The early embryology of Diabrotica undecimpunctata howardi (coleoptera: Chrysomelidae) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 121-137 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Early embryogenesis is described for the southern corn rootworm, Diabrotica undecimpunctata Howardi Barber, at 24 ± 1°C. During the first four hours following oviposition, the maturation divisions and syngamy are completed. Morphological changes in the second polar body accompany syngamy. Cleavage divisions and energid migration occur during the fourth to the tenth hour. The vitellophags, which appear during cleavage divisions, are distinguished from the blastema-bound nuclei by having smaller, more densely staining nuclei. After completion of a uniform blastoderm (11-14 hour), cell division ceases until the completion of the germ band and the formation of the embryonic membranes (22 hour). This species has a pattern of amnion formation that is different from most Coleoptera but is shared with a few other chrysomelids, some Isoptera, and some Odonata.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490107
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  • 58
    Digitale Medien
    Digitale Medien
    Neuronal pathways from the dorsal acelli of the house cricket, Acheta domesticus (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 105-119 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Each ocellar nerve in the house cricket Acheta domesticus contains giant nerve fibers of 10-15 μ diameter, characterized in Golgi Cox preparations by a single row of short collaterals which runs along nearly the entire length of a fiber. Numerous long collaterals are given off by thin fibers in the ocellar nerve; medium-size fibers give off relatively few collaterals.The lateral ocellar tracts extend posteriorly through the dorsal protocerebrum, crossing the protocerebral bridge dorsally. The smaller median ocellar tract runs more ventrally through the pars intercerebralis; posterior to the bridge its fibers turn out toward the lateral nerves. Golgi and cobalt preparations reveal branching of giant and mediu_-size ocellar fibers posterior to the bridge at two levels, forming bilateral regions of ocellar neuropile. No ocellar processes appear to be given off to the corpora pedunculata, centra! body, nervi corporis cardiaci, antenna! lobes, or circumesophageal connectives; it is uncertain whether ocellar collaterals extend into the protocerebral bridge or optic lobes. Cell bodies of giant and medium-sized fibers are located in the pars intercerebralis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490106
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  • 59
    Digitale Medien
    Digitale Medien
    Morphology of the gills of larval and parasitic adult sea lamprey, Petromyzon marinus L. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 73-103 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The general morphology of the gills is similar in larval (ammocoetes) and parasitic adult sea lampreys, Petromyzon marinus, despite different methods of ventilation necessitated by their feeding habits.The gill lamellae are supported by randomly-distributed pillar cells which enclose blood spaces and collagen columns. The distribution of these cells in lampreys is different from that of higher fishes and it may be inefficient for respiratory exchange. The presence of cytoplasmic microfilaments suggests that these cells have the ability to reduce the lamellar blood spaces through contraction. Marginal channels at the tips of the lamellae are lined only by endothelial cells.The thickness of the water-blood pathway in lampreys falls within the range described for higher fishes, with the most efficient gas exchange likely occurring at the lamellar tips where only a single layer of epithelial cells is present. The abrupt increase in height of the epithelium near the lamellar bases in adults, compared to the gradual transition in height along the lamellae in ammocoetes, is perhaps reflective of higher oxygen requirements during the parasitic stage. The consistent appearance of wide, lateral intercellular spaces within the respiratory epithelium of lampreys indicates possible involvement of these spaces in transport.Mucous secretion appears to be an important function of the superficial platelet cells in ammocoetes. “Mitochondria-rich” and “mitochondria-poor” superficial cells are observed in both ammocoetes and adults, with the mitochondria-rich cells more prevalent toward the lamellar bases. The possibility that at least some of these cells may be involved in absorption is discussed. Mitochondria-rich cells in the interlamellar region are morphologically different in ammocoetes and adults but all possess an abundance of smooth endoplasmic reticulum and hence resemble “chloride cells” of higher fishes. The similarity of these cells in the parasitic adult lamprey to chloride cells of marine fishes may reflect the potential of the adult lamprey to osmoregulate in salt water. A scarcity of these cells in ammocoetes and their resemblance to chloride cells in freshwater fishes may reflect the restriction of larval lampreys to a freshwater habitat.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490105
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  • 60
    Digitale Medien
    Digitale Medien
    The nature and development of sex attractant specificity in cockroaches of the genus Periplaneta. I. Sexual dimorphism in the distribution of antennal sense organs in five species (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 139-157 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Sexual dimorphism in the distribution of antennal sense organs is common among adults of the genus Periplaneta. In three out of the four strains of Periplaneta americana examined, adult males had more contact chemoreceptors than females. In the fourth strain of P. americana and in P. australasiae, P. brunnea, P. fuliginosa, and P. japonica, no statistically supportable sexual dimorphism of contact chemoreceptors was found. However, in all strains and species of Periplaneta examined, sexual dimorphism was found in the total number and/or density of olfactory sensilla. Male adults had nearly twice as many olfactory sensilla as female adults. These observations are consistent with the behavioral observation that males within the genus Periplaneta rely on the reception of an airborne pheromone for the initiation of courtship behavior. In P. americana, where sexual dimorphism was found in the contact chemoreceptors, contact stimuli release the full wing raising display and presentation in males during courtship.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490202
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  • 61
    Digitale Medien
    Digitale Medien
    Ultrastructure of the main excretory duct of the cat submandibular gland (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 183-197 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The main excretory ducts (MED's) from the submandibular gland of adult cats were examined by electron microscopy. The ducts consisted of a pseudostratified epithelial lining surrounded by abundant connective tissue and numerous, small, longitudinally-oriented blood vessels. The taller epithelial cells were closely coherent, without the luminal clefts between adjacent cells that are characteristic of rat MED's. In the cat, these cells lacked basal membrane specialization, but showed considerable lateral interdigitation. Some microvilli were present on the apical surface. In a'few rare cells, the luminal surface bore cilia of typical appearance. The smaller, pyramidal basal cells had irregular basal surfaces that gave rise to one or more long cytoplasmic processes. The basal surface of the pyramidal cells was studded with hemidesmosomes. The cytoplasm contained abundant tonofilaments, which sometimes aggregated in prominent perinuclear bundles. Occasional goblet cells were present in the duct wall.MED's perfused either in situ or in a perfusion chamber with Locke's solution also were studied. Even after perfusion of 160 minutes duration, the ultrastructure of the ductal epithelium showed remarkably few alterations. The MED model system thus remains stable long enough to carry out physiological experiments which may produce ultrastructural alterations.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490204
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  • 62
    Digitale Medien
    Digitale Medien
    The structure and formation of the byssus attachment plaque in Mytilus (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 199-221 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The byssus attachment plaque and the tissues responsible for its formation were studied in M. califomianus by light microscopy and by transmission and scanning electron microscopy. It was shown that the plaque consists of at least three phases which ultrastructurally resemble three secretions considered to be collagen, mucoid material and polyphenol. The mucoid and polyphenol appear to mix as a colloidal suspension in which the latter is the continuous phase and forms the definitive bonding surface. Plaque collagen represents an extension of thread material into the cementing substance.Stimulated secretion within the ducts and distal depression of the mussel's foot shows a continuum of increasing heterogeneity from the inner toward the outer regions. This reflects the distribution of exocrine cell apices wherein exocytosis of polyphenol granules predominate deeply, mucous granules superficially and collagen granules in between.It is proposed that the morphology of the plaque conforms to theoretical physical-chemical requirements for adhesion under water.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490205
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  • 63
    Digitale Medien
    Digitale Medien
    The cranial arteries of turtles and their evolutionary significance (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 159-182 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: In this paper the cranial arteries, cranial arterial foramina, and bony canals of the Cheloniidae, Chelydridae, Pelomedusidae, and Chelidae are described in detail. From skull studies and published material, the general cranial arterial patterns of all the turtle families can be inferred. Sea turtles, the Cheloniidae and Dermochelyidae, possess both a large stapedial artery and a large artery supplying the orbit, which is possibly similar to the primitive cranial arterial pattern for turtles. From a primitive pattern in which stapedial and palatine arteries supply the orbit, the Chelydridae and Testudinidae retained a large stapedial artery and reduced the palatine artery, while the Kinosternidae and Dermatemydidae developed a large palatine artery and reduced the stapedial artery. The Trionychidae and probably the Carettochelyidae evolved a complex arterial pattern in which the stapedial artery was reduced somewhat and the pseudopalatine artery was substituted for the palatine artery. Pleurodires in general retained a large stapedial artery and reduced or eliminated the palatine artery. The Podocneminae, including the Madagascar species, developed a highly modified carotid canal, which is found in no other turtle group. The facts which have been presented should aid in fossil skull studies and in understanding the evolutionary background of recent turtles.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490203
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  • 64
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490301
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  • 65
    Digitale Medien
    Digitale Medien
    Laser microbeam irradiation of rat kangaroo cells (PTK2) following selective sensitization with bromodeoxyuridine and ethidium bromide (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 327-337 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Ethidium bromide (l0 μg/ml) and bromodeoxyuridine (25 μg/ml) were used to sensitize selective cell organelles to visible wavelengths of an argon ion Her (488 and 514 nanometers). Ethidium bromide was shown to be salabtlve In sensitizing nucleoli, chromosomes, and the centriolar region of PTK2 cells to the laser microbeam. Similarly, BrDU sensitized chromosomes to the microbeam irradiation. The lesions produced on the chromosomes when either agent was used appeared as a phase paling of the irradiated segment. Nucleolar lesions also appeared as a phase paling, and the centriolar region alteration appeared either as a phase paling or a phase darkening.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490303
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  • 66
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500101
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  • 67
    Digitale Medien
    Digitale Medien
    Structural changes occurring during transformation of the labial gland cells to their adult form, in Manduca sexta (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 547-565 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The labial gland of the adult sphingid moth, Manduca sexta, is composed of five distinct regions, each made of a single cellular type. Four of these regions are derivatives of the single specialized cellular population that makes up the caterpillar labial duct.Both the larval labial duct and its derivatives are large, polyploid cells with pleiomorphic nuclei. There is a definite cellular continuity between the larval and adult forms of these cells throughout metamorphosis; no mitoses or cell deaths are seen to occur in the gland during transformation.Cytological studies indicate that in the process of cell transformation the ducts first “dedifferentiate,” elongate, then redifferentiate. Intermediates in this process have well defined structures which should make this system useful in studying covert events in the transformation process.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490407
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  • 68
    Digitale Medien
    Digitale Medien
    Effects of continuous light and darkness on the eyes of the troglobitic salamander Typhlotriton spelaeusThis paper is based in part on a dissertation submitted by the senior author in partial fulfillment of requirements for a Ph.D. degree at Southern Dlinois University at Carbondale. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 527-545 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Larval Typhlotriton spelaeus collected from five caves in Pulaski Co., Missouri, were kept as larvae or induced to transform in darkness or continuous fluorescent illumination. Larvae maintained in darkness for 215 and 279 days had smaller eyes, smaller rod inner and outer segments, and fewer metaphase figures in the genninative zone of the neural retina than comparable larvae maintained in light (258 lux). Except for visual cell size, differences were small and for each characteristic exceptions were observed. One larva kept in light showed early retinal degeneration comparable to that in transformed adults of T. spelaeus. All larvae exhibited optomotor behavior both before and after the experiment.Among animals induced to transform by L-thyroxin and maintained in darkness 111 to 366 days, visual cell and pigment epithelium degeneration was more extensive and more frequent than in animals kept for the same length of time in light (237-298 lux). In darkness the frequency of animals with retinal degeneration increased between 111 and 366 days. In light some animals exhibited pigment epithelium reduction with normal visual cells, and others had free, pigmented cells in the subretinal space. These effects were not comparable to degeneration in darkness. Eyelids covered the eyes of only a few animals in both light and dark treatments. The extent of eyelid encroachment over the eye was greater in darkness than in light. Most animals exhibited optomotor responses after experiments, but responses of animals kept in darkness were impaired in comparison to those of animals kept in light.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490406
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  • 69
    Digitale Medien
    Digitale Medien
    The pectoral anatomy of selected Ostariophysi. II. The Cypriniformes and siluriformes (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 79-115 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The pectoral myology and osteology of the cyprinoids Notemigonus crysoleucas, the golden shiner, and Catostomus commersonnii, the common white sucker, resemble those of generalized, lower teleosts in structure and function, except in features related to the manipulation of the massive fifth ceratobranchial of cyprinoids by muscles attaching on the girdle. Catostomus is more specialized in having unique intercostal muscles to the girdle, complex subclavian arteries and lack of a superficial trapezius muscle. The bony pectoral anatomy of the siluriform, Ictalurus nebulosus, the brown bullhead, is highly specialized in relation to the presence and locking of the massive pectoral spine which is formed of fused dorsal and ventral propterygial rays; there is consolidation of the girdle through fusion of bones, presence of unique stabilizing bony structures, firm symphyseal union of bilateral girdles and the presence of friction-surfaces of girdle and spine for locking. The movements of the spine are specialized in the greater guidance offered by the girdle. Myological specializations are related mainly to ventral appendicular muscles which lock the spine. The nervous and arterial systems are generalized.
    Zusätzliches Material: 19 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500105
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  • 70
    Digitale Medien
    Digitale Medien
    The structure of the hypothalamic inferior lobes of the blacktip reef shark: Scanning and transmission electron microscopic observations (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 59-78 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The inferior lobes of the shark hypothalamus were examined with light, transmission and scanning electron microscopy. The cells bordering the floor of the lateral recess appear to be typical liquor-contacting neurons. With scanning electron microscopy (SEM) the apical ends of these cells are seen to bulge into the ventricular lumen. In contrast, the roof is lined by a more typical ependymal cell characterized by numerous cilia and microvilli. In addition, SEM reveals several kinds of supraependymal cells with processes that appear to penetrate the ventricular lining. A periventricular nucleus underlies the ependymal cells. Neurons of the periventricular nucleus contain numerous lipofuchsin granules. The rest of the inferior lobe consists of many neuronal fibers. The morphology of the hypothalamic inferior lobe is discussed in relation to its possible role in feeding and aggressive behavior in both elasmobranchs and teleosts.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500104
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  • 71
    Digitale Medien
    Digitale Medien
    Studies on the intestine of Daphnidae (Crustacea, Cladocera) ultrastructure of the midgut of Daphnia magna and Daphnia obtusa (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 711-725 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The fine structure of midgut cells in two species of Cladocera (Crustacea: Branchiopoda) has unique features when it is compared to that in the midguts of other arthropods. Features which suggest that food is absorbed in digested form are: the presence of the peritrophic membrane, the glycocalyx, the almost complete absence of pinocytotic vesicles, and the large surface area of a great number of microvilli. Digested products presumably pass into the hemolymph through the network of extracellular canals and cisterns surrounding the basal ends of intestinal epithelial cells. Cells of the midgut in Cladocera differ from those of other arthropods in the simplicity of their basal plasma membranes, which are not highly folded. The small number of membrane invaginations suggests that water reabsorption is very slight, as is the usual condition in aquatic animals.The origin and evolution of peculiar structures we call “multivesicular-like bodies” have been investigated. These display a variety of different morphological features. Some contain acid phosphatase activity and are considered as specialized lysosomes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500306
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  • 72
    Digitale Medien
    Digitale Medien
    Scanning microscopy of collagen in the basement lamella of normal and regenerating frog tadpoles (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 805-823 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The arrangement of collagen fibers over the body surface in the basement lamella of Pseudaeris and Xenopus tadpoles is described. It can be viewed by scanning microscopy after removal of epidermis and basal lamina by trypsin treatment of alcohol fixed tissue. The orthogonal array is modified in regions where fiber direction changes extensively such as the base of the ventral fin or the posterior part of the head. In these regions “exceptional points” in the orthogonal pattern occur, as described by Rosin (1946). The pattern is bilaterally symmetrical. In the region of the nasal opening the orthogonal pattern is replaced by a mat of randomly oriented fibers. In tail regeneration the wound area is marked by aberrant disposition of collagen anteriorly then a mat of randomly disposed fibers followed posteriorly with a sharp transition to the orthogonal pattern of the regenerate. No fiber terminations could be seen in normal or regenerating regions of the lamella.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500403
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  • 73
    Digitale Medien
    Digitale Medien
    Reproductive morphology and Spermatogenesis in Dermanyssus gallinae (DeGeer) (Acari: Dermanyssidae)Supported in part by Public Health Service Research Grant AI-09556 from the National Institute of Allergy and Infectious Diseases. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 150 (1976), S. 825-842 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Sperm induction pores, tubuli annulati, rami sacculi, sacculus foemineus, cornu sacculus and acantho-membranous hood in female Dermanyssus gallinae support the probability of coxal insemination as reported for some other mesostigmatid species.Development of the circular testis in males (from fusion of two anterolaterally projecting protonymphal testicular arms) and formation of haploid (n = 3) spermatids from haploid (n = 3) spermatogonial cells is entirely mitotic. Spermatogenesis begins within one hour after protonymphal feeding and continues through adult ecdysis in normally fed individuals. Nutritional deficit causes cessation of spermatogenic divisions in deutonymphs starved 23 days, but is rapidly rejuvenated upon feeding. No rejuvenation of division was observed in adult males given the opportunity to feed, thus adult males might not feed.
    Zusätzliches Material: 18 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051500404
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  • 74
    Digitale Medien
    Digitale Medien
    The functional anatomy of the hindlimb of some african viverridae (Carnivora) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 227-253 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The functional anatomy of the hindlimb of 12 species of viverrids was studied with relation to locomotion. The animals were allocated to primary locomotor categories on the basis of their anatomy and locomotion.The climbing, arboreal walking category (Nandinia binotata) is characterized by a small sacroiliac articulation, the iliopsoas inserts onto a medially located lesser trochanter and the femoral condyles are not posteriorly placed. The hindfoot is plantigrade and its structure permits considerable movement. The pads are soft and the claws retractile.Representatives of the arboreal and terrestrial walking and jumping category (Genetta genetta, G. servalina, G. tigrina) have a plantigrade forefoot and digitigrade hindfoot. The lesser trochanter is more posteriorly placed than in the climbing category. A previously undescribed muscle, the caudofemoralis profundus extends from several anterior caudal vertebrae to the femur. The tibio-astragular joint restricts supination of the foot. There is little mediolateral movement in the digitigrade foot. The claws are retractile.In the general terrestrial walking and scrambling group (Helogale parvula, Mungos mungo, Atilax paludinosus, Bdeogale crassicauda, Herpestes ichneumon, H. sanguineus) the animals have essentially similar hindlimbs except for size differences and modifications to the feet. Helogale and Mungos have large medial epicondyles on the humerus and large terminal phalanges. Bdeogale has a vestigial first metatarsal, while Atilax can splay its digits. In all species the distal phalanges are non retractile.The trotting category (Civettictis civetta. Ichneumia albicauda) is characterized by longer epipodials and metapodials and a more proximal position of muscle bellies. Most of the adaptations minimize rotation, adduction and abduction of the leg and supination of the foot. The metatarsals are closely adjoined and the distal phalanx is stout and non -retractile.There appear to be two levels of locomotory adaptation. Major adaptations affect the whole appendicular skeleton and are used to assign animals to primary locomotor categories. Minor adaptations occur mainly in the foot and indicate the more specific habits of the animal.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480208
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  • 75
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480301
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  • 76
    Digitale Medien
    Digitale Medien
    The modified midventral scales of Percina (Osteichthyes; Percidae) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 255-264 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The modified midventral scales on Percina males probably function to induce tactile stimulation of the female during spawning. The midbelly row of modified scales presumably evolved as a result of increased selective advantage of larger and more strongly toothed scales on the midventer; primitive and intermediate conditions in the evolution of the modified scales as well as a distinctly modified row are extant, The morphology of the scales varies seasonally and ontogenetically. The scales are permanent rather than deciduous as described in the literature interspecific variation of the modified scales is pronounced intersubgenerically. less so intrasubgenerically.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480209
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  • 77
    Digitale Medien
    Digitale Medien
    Tongue evolution in the lungless salamanders, family plethodontidae I. Introduction, theory and a general model of dynamics (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 265-286 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Plethodontid salamanders capture prey by projecting the tongue from the mouth. An analysis of theoretical mechanics of the hyobranchial skeleton is used to formulate a working hypothesis of tongue movements. Predictions that the skeletal elements of the tongue are included in the projectile and that the hyobranchial skeleton is folded during projection are central to the analysis, When decapitated in a particular way, salamanders project the tongue, and it is not retracted. When these heads are fixed and sectioned, examination confirms the predictions, In turn, these observations are used to refine the working hypothesis and to generate a general model of tongue dynamics for plethodontids. Muscles performing the major roles of projection (subarcualis rectus I) and retraction (rectus cervicis profundus) are identified. The skeleton is folded passively along a morphological track having the form of a tractrix, Predictions concerning the shape of the track and the exact configuration of the folded skeleton are confirmed by study of sectioned material. The skeleton unfolds along the track during retraction and is spread into the resting state, The model developed herein will be used as a basis for predictions concerning selection patterns in the family and for analytical purposes in comparative and evolutionary studies.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480302
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  • 78
    Digitale Medien
    Digitale Medien
    Feeding adaptations in the hairs and tongues of nectar-feeding bats (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 329-336 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Scales on the hairs of pollinating bats spread out at an angle to the main hair shaft. In contrast, the hairs of most bats not associated with plants are relatively smooth. Both megachiropteran and microchiropteran flower-feeding bats show this divaricate scale structure which may aid in the collection of a heavy coating of pollen. Some of the pollen is transferred to subsequent flowers, but most is groomed from the fur and ingested as the only reliable nitrogen source for the bat.The tongues of nectar-feeding bats also show structural modifications which allow efficient uptake of the carbohydrate fraction of the diet.Structural specializations of the hairs and tongue are analogous to those seen in other nectar-feeding animals.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480305
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  • 79
    Digitale Medien
    Digitale Medien
    The extrinsic blood vessels of the ovary of the sheep (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 287-303 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The extrinsic ovarian blood vessels were studied in 134 ewes. In view of recent evidence that uterine luteolysis may involve local veno-arterial transfer of prostaglandin F2α in the ovarian pedicle, particular attention was paid to the interrelationships between veins and arteries.The ovarian artery and utero-ovarian vein are large vessels of conventional structure and lie in close apposition. Their walls are slightly thinner on their apposing sides. The ovarian branches of the ovarian artery are very tortuous, and closely intertwined with the plexiform ovarian branches of the utero-ovarian vein.An extensive plexus of small veins surrounds the ovarian artery and its ovarian branches. Within this plexus are many thin-walled, dilated regions, interspersed with narrow, thick-walled segments. Valves are inconstantly present at sites of entry of branches of the plexus into the major veins. Small numbers of arterio-venous anastomoses are present in the distal part of the ovarian pedicle.Unless blood can flow in a veno-arterial direction through arterio-venous anastomoses or capillary beds, the structural barrier between uterine venous and ovarian arterial blood is substantial.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480303
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  • 80
    Digitale Medien
    Digitale Medien
    Spinal nerves and their bearing on, salamander phylogeny (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 305-327 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Examination of the vertebral columns of representatives of all families of salamanders revealed that, in contrast to the condition found in most other vertebrates, salamander spinal nerves often pass through foramina in the vertebrae. Two kinds of spinal nerve foramina were found: those in the anterior halves of vertebrae, and those in the posterior halves. In addition, many salamanders retain intervertebral nerves. However, within each family or, in a few cases, subfamily there is a characteristic pattern of spinal nerve-vertebral relationships.The first spinal nerve of all salamanders exits through a foramen in the anterior half of the atlas. All more posterior nerves are intervertebral in the families Cryptobranchidae, Hynobiidae and Proteidae. The posterior caudal nerves exit through the posterior halves of the caudal vertebrae in the family Amphiumidae, while in the subfamilies Dicamptodontinae and Rhyacotritoninae all post-sacral nerves exit through the posterior halves of the vertebrae. All but the first three nerves exit through posterior foramina in the family Plethodontidae and the subfamily Ambystomatinae, while all but the first two nerves pass through posterior foramina in the families Salamandridae and Sirenidae.Several fossil salamanders were also examined. These showed that the amphiumid and dicamptodontine-rhyacotritonine nerve patterns had evolved by the Late Cretaceous, and the sirenid pattern had probably evolved by that time. Other Cretaceous genera associated with the Ambystomatoidea still possessed the primitive intervertebral pattern.Using spinal nerve patterns and several other previously described morphological characters, a new hypothesis of the phylogeny of recent and fossil salamanders is presented and compared to earlier proposed phylogenies of the group. A new classification of salamander families is presented.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480304
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  • 81
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480401
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  • 82
    Digitale Medien
    Digitale Medien
    Oral food processing in two herbivorous lizards, Iguana iguana (Iguanidae) and Uromastix aegyptius (Agarnidae) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 363-390 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The anatomy and function of the feeding apparatus in Iguana iguana and Uromastix aegyptius were studied by dissection, cinematic and cineradiographic techniques.The feeding behavior of these species differs from that of insectivorous lizards in the cropping action which separates a piece from the whole plant. The food is manipulated by a fleshy tongue and by movements of the whole head. There is no mastication of food. The cropping action involves movement of both the upper jaw around the atlantooccipital joint and the lower jaw around the mandibular joint; and in Uromastix only, streptostylic movement of the quadrate. Often movements of the whole head playa supplementary role in the cropping action.In both species the feeding apparatus has been modified to facilitate cropping. In Iguana the pleurodont dentition is multicusped and laterally compressed. Each tooth forms a shearing blade whose function does not require contact with other teeth. In Uromastix the dentition is acrodont and the cheek teeth are massive and lack cusps. Occlusion is necessary for shearing plant material. The skull system of Uromastix also has a number of modified structures which allow protraction and retraction of the lower jaw to facilitate cropping while maintaining a gape equivalent to that in Iguana. It is suggested that the differences in the feeding apparatus between Iguana and Uromastix are attributable to differences in the mode of tooth replacement and implantation.
    Zusätzliches Material: 15 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480307
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  • 83
    Digitale Medien
    Digitale Medien
    Studies on the formation of germ cells in a compound ascidian Botryllus, primigenus okaContribution from the Shimoda Marine Biological Station No. 301. (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 337-361 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Gametogenesis of a compound ascidian Botryllus primigenus was studied histologically. On either side of the zooid (stage 9), in the gonadal space between the epidermis and the atrial epithelium, either a single testis or a complex of an egg follicle and a testis can be formed. The egg follicle consists of a single ovum (occasionally two ova) and its accessory cells and is connected with the atrial epithelium by the follicle stalk. The egg follicle is always accompanied by the brood pouch, a diverticulum of the atrial cavity. The testis is equipped with a vestigial spermiduct and is attached to the atrial epithelium.Buds of stage 8 comprise, besides the developing testes and, egg follicles, loose aggregations of hemoblasts and oocytes of early developmental stages, which are already accompanied by primary follicular cells. Both the oocytes and the primary follicular cells seem to arise from the hemoblasts. The young oocytes are isolated in the gonadal space of the buds nnd are transferred to buds of the succeeding generations until they finally mature.In the bud of stage 3, a compact mass of cells appears, attaching to tbe inner vesicle on either side of the body. It is derived from the hemoblasts lodged there in the preceding generation and presumably also from the circulating hemoblasts. When the cell mass receives a large oocyte derived from the preceding generation, part of the cell mass differentiates into egg envelopes, forming an egg follicle, and a follicle stalk and the remainder into a testis. When the cell mass receives no oocyte, it differentiate as a whole into a testis. In the egg follicle thus formed the outer and inner follicular cells increase in number by mitotic division. Subsequently, initial test cells are derived from the inner follicle by migration across the developing chorion; then they increas2 in number by mitosis. In the testis, meiosis and spermiogenesis take place.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480306
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  • 84
    Digitale Medien
    Digitale Medien
    Secretion of embryonic envelopes and embryonic molting cycles in Hemioniscus balani Buchholz, Isopoda Epicaridea (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 427-451 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The fertilized egg of Hemioniscus balani, a viviparous isopod, is encased in two envelopes, I and II, the structure of which is described.In the course of its development, the embryo secretes five successive sacs called embryonic envelopes. Both their structure and the means of secretion by the embryo are analyzed through thin sections. The presence of these successive secretion cycles together with exuviations involving these embryonic envelopes lead us to believe that during embryonic development in Hemioniscus balani, embryonic molting cycles exist.The appearance and shedding of the envelopes of the fertilized egg and embryo allow determination of ten embryonic stages which are briefly described.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480403
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  • 85
    Digitale Medien
    Digitale Medien
    The structure of the ovarian ball and oogenesis in Moniliformis dubius (Acanthocephala) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 391-426 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Seven to nine days after infection of the definitive host (rat) by cystacanths, the genital primordium of the female acanthocephalan is transformed from a fragmented mass of cells into discrete ovarian balls. This is accomplished by envelopment of free germinal cells by somatic tissue which originates from the ligament sac primordium. Germinal cell nuclei then undergo repeated mitoses until about 21 days of development, with concurrent formation of oogonial syncytia which occupy the interior of the ovarian balls. Oocytes, derived from these oogonia, move to the periphery of the germinal syncytia for differentiation, growth, fertilization, shell formation, and release from the ovarian ball. After oogonial proliferation ceases, continued growth of the ovarian ball apparently results from increase in size of already present cells.Free-floating mature ovarian balls are found in the dorsal ligament sac; each consists of germ cells in various developmental stages, enveloped and pervaded by a multinucleate matrix syncytium of somatic origin, which functions as a follicle. Spermatozoa pass through the matrix cell for the internal fertilization of mature oocytes. Myelinated structures of an undetermined nature were found to correspond to previously reported polar bodies. After 100 days post-infection, the somatic matrix syncytium begins to manifest the degenerative effects of aging. The germinal tissue exhibits no subcellular signs of senescence by 154 days, but decreases in amount in older worms.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480402
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  • 86
    Digitale Medien
    Digitale Medien
    Masthead (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976) 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490101
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  • 87
    Digitale Medien
    Digitale Medien
    Oildroplets in the eyes of adult anuran amphibians: A comparative survey (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 148 (1976), S. 453-468 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Oildroplets in the eyes of terrestrial vertebrates are spherical cellular organelles that stain for lipids, have no discernible internal structure, and often contain carotnoids and possibly other chemicals. A survey of 97 species of anuran amphibians (frogs and toads) revealed that all speccies of 16 families surveyed possessed yellow oildroplets of varying size in the cells of the pigment epithelium, except for three species that appear to have secondarily lost them during evolution. Furtbermore, 25 species of six families also possess colorless oildroplets at the distal end of the inner segments of single cones and principal cones of the double-cone system; two species of the Ranidae appear to have secondarily lost such retinal oildroplets. Every species possesses epithelial or retinal oildroplets or both. Lastly, small oildroplet-like inclusions were discovered in the red blood cells of two species.All of Walls' ('42) summary generalizations about anuran oildroplets are incorrect: oildroplets are not restricted to the Ranidae, are not yellow when found in the cones, and do not correlate with phototactic behavior in 87 species. Evidence is reviewed suggesting that the primary function of anuran oildroplets is chemical storage, perhaps related to the visual pigment cycle. Oildroplets in the cones may additionally act as filters of ultraviolet radiation.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051480404
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  • 88
    Digitale Medien
    Digitale Medien
    Anatomy and ultrastructure of the excretory system of the lizard, Sceloporus cyanogenysThis research was supported by NIH Grant AM 15972 and in part by DGF (SFB 146). (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 279-326 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The anatomy and ultrastructure of the lizard kidney (Sceloporus cyanogenys) have been studied by light and electron microscopy. The number of glomeruli was counted' in serial sections and estimated to be 2,000 (in the two kidneys). Beginning with the glomerulus and Bowman's capsule the nephron segments are sequentially: (a) proximal tubule; (b) intermediate ciliated segment consisting of a proximal and distal part; (c) distal tubule, which can be divided into two segments, followed by (d) connecting tubule and (e) initial collecting duct. The initial collecting ducts from several nephrons open into the collecting duct. Tubular epithelium in this lizard has similarities to that of other reptiles, The lateral borders do not overlap like in mammals, but interdigitate by fingerlike projections. The length of the nephron segments was measured in disected tubules and the diameter was measured on light and electron micrographs. From these measurements estimates of inner tubular surface area were made. Together with data from physiological studies (Stolte et al., '76; Schmidt-Nielsen, '76) the estimated surface area was used to calculate transport rates per unit area across the epithelium. Comparisons of structure and transport rates were made between S. cyanogenys and other reptiles and mammals.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490302
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  • 89
    Digitale Medien
    Digitale Medien
    Ultrastructural investigation of the mechanism of muscle attachment to the gastropod shell (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 339-351 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The ultrastructure of the muscle-shell attachment was investigated in the land pulmonate snails Helix aspersa, Anguispira altemata, in the freshwater pulmonate Laevipex sp., and in the freshwater prosobranch Pomacea paludosa. In all cases, a collagenous intercellular matrix and a specialized epithelium (tendon cells) intervene between the columellar muscle and the shell. These tendon cells are characterized by hemidesmosomes at both apical and basal ends, connected by thick bundles of microfilaments. The tendon cells do not insert into the shell directly by microvilli, as formerly thought, but by an extensive network of extracellular organic fibers.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490304
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  • 90
    Digitale Medien
    Digitale Medien
    Aspects of skeletal mechanics of the starfish Asterias forbesii (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 353-367 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The skeletal mechanics of Astenas forbesii are examined in order to erect a theoretical framework for the evaluation of starfish skeletal systems. Guided by engineering theory, the skeleton is dissected into its functional parts and an approximation made of the stresses sustained by each. All relevant mathematical operations are demonstrated. It is shown that the whole body acts as a unit sustaining compressive forces across its oral surface and tensile stresses across its aboral surface. Two points of maximum stress are identified: the aboral ridge of the ray close to the disk and the inferior transverse amhulacral muscle (ITAM). Structural stability is conferred upon the former by virtue of its position in the body and upon the latter by the inclusion of strong tensile fibres in parallel with the muscle.
    Zusätzliches Material: 12 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490305
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  • 91
    Digitale Medien
    Digitale Medien
    The development of the septum primum relative to atrial septation in the mouse heart (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 369-381 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The septum primum in the mouse originates as a thickened primordium with a straight rather than a sickle-shaped ventral border. It is covered on its ventral border by anterior cushion material which is continuous over the roof of the atrium with the principal anterior cushion mass.A process of cavitation thins the septum primum and precedes actual fenestration. This process shifts the membranous septum to the left thereby providing room for the septum secundum to overlap on the right side. The septum primum cannot contact the posterior cushion until closure of the sinus venosus gutter which is described. The closure of the interatrial foramen, later the foramen primum, is accomplished by cell growth of the anterior cushion material.The ventral thick border of the septum primum contributes to the ventral limbus and the caudal thickened boundary of the fossa ovalis with some contribution from the left venous valve. These boundaries as well as the membranous portion of the interatrial septum are derived from the same primordium, namely the septum primum.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490306
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  • 92
    Digitale Medien
    Digitale Medien
    The ultrastructure of the hepatopancreatic caeca of Gammarus minus (crustacea, amphipoda) (1976)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 149 (1976), S. 383-399 
    Details
    ISSN: 0362-2525
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: The hepatopancreatic caeca of the freshwater amphipod Gummarus minus are four tapered blind pouches lined with a simple columnar epithelium bearing an apical surface of regular microvilli and resting on a basement membrane. This epithelium is enclosed by a tonic, striated muscularis. Each caecum consists of three regions. The distal zone is formed of embryonic cells having a high nuclear to cytoplasmic ratio and giving rise to the other cell types. The second or differentiation zone consists of regular tall columnar cells of two morphological types:(1) light staining R-cells which have a large number of lipid droplets and few Golgi bodies; (2) basophilic F-cells which have numerous distended Golgi bodies. The more proximal secretory zone forms the majority of each diverticulum. This mature zone is formed from R-cells and large, basophilic, vacuolated B-cells which differentiate from F-cells. The secretory cell sequence appears to be E-cell  -  F-cell  -  B-cell with secretion being apocrine in nature. The exact relationship of Rcells to the other cell types is questionable, but the R-, F - and B-cells all appear to be able to absorb and store nutrients. Within the Malacostraca the hepatopancreatic epithelium of Amphipoda more closely approximates that of Decapoda than that of the Isopoda.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jmor.1051490307
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  • 93
    Digitale Medien
    Digitale Medien
    4-Amino-2-cyanmethylen-Δ4-thiazoline (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 343-346 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180220
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  • 94
    Digitale Medien
    Digitale Medien
    Lösungsmittelinduzierte Elektronenstrukturänderungen bei negativ solvatochromen Farbstoffen13. Mitteilung über Solvatochromieprobleme. 12. Mitt.: vgl. [1]. (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 321-326 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Solvent-induced Changes of the Electronic Structure of Negatively Solvatochromic DyesThe 1H NMR chemical shifts of negatively solvatochromic dyes depend on the polarity of the solvent used. The differences of the chemical shifts of vicinal protons decrease with increasing polarity. This result supports the idea that the electronic structure of negatively solvatochromic dyes changes from a polymethine-like state in non-polar solvents to a polyene-like state in polar solvents.
    Notizen: Die chemischen Verschiebungen des Protonenresonanzspektrums von negativ solvatochromen Farbstoffen hängen von der Polarität des verwendeten Lösungsmittels ab, wobei die Differenzen der chemischen Verschiebungen benachbarter Protonen mit zunehmender Polarität abnehmen. Dies deutet auf eine lösungsmittelinduzierte Veränderung der Elektronenstruktur von einem mehr polymethinähnlichen Zustand in unpolaren Lösungsmitteln in Richtung auf einen polyenähnlichen Zustand in polaren Lösungsmitteln hin.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180217
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  • 95
    Digitale Medien
    Digitale Medien
    Synthese phenylsubstituierter Alkendiine durch alkalischen Abbau der Mannichbasen-Methojodide von Phenylalkadiinen-(1.3) (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 381-389 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Synthesis of Phenyl-substituted Alkene-diynes by Alkaline Degradation of Quaternary Salts of Mannich Bases Derived from Phenyl-alka-1,3-diynesIsomeric phenyl- and p-methoxyphenylsubstituted hexenediynes are formed by alkaline degradation of quaternary salts of aryldiacetylene-Mannich bases. The reaction is a diethynylogic Hofmann elimination. The degradation with sodium amide mainly results in the formation of trans-alkenediynes with a terminal triple bond. Using aqueous potassium hydroxide, the degradation yields the isomers with terminal double bond exclusively. This is in contrast to the reaction of aliphatic diacetylene-Mannich base methoiodides.
    Notizen: Isomere Phenyl- und p-Methoxyphenylhexendiine werden durch alkalischen Abbau quartärer Salze von Aryldiacetylen-Mannichbasen über eine diäthinyloge Eliminierung erhalten. Der Abbau mit Natriumamid ergibt bevorzugt die Alkendiine mit endständiger Dreifachbindung in der trans-Konfiguration. Beim Abbau mit wäßriger Kalilauge entstehen im Gegensatz zu den nicht phenylsubstituierten Diacetylen-Mannichbasen ausschließlich die Isomeren mit endständiger Doppelbindung.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180305
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  • 96
    Digitale Medien
    Digitale Medien
    Steroide. XLVIII. 16α-Heterosubstituierte Östradiol-3-methyläther (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 483-488 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Steroids. XLVIII. 16 α-Heterosubstituted 3-Methoxy-estra-1,3,5(10)-triene-17β-olsThe synthesis of 16α-heterosubstituted 3-methoxy-estra-1,3,5(10)-triene-17β-ols 2a - 2e from 16β-bromo-3-methoxy-estra-1,3,5(10)-triene-17β-ol 1 by substitution with nucleophiles is described. Additional compounds of this class 2f - 2h are obtained by transformation of the new 16α-substituents. Jones oxidation of 2b and 2c yields the 17-keto compounds 3b and 3c. The configuration of the new compounds is confirmed by i.r. and 1H n.m.r. spectra.
    Notizen: Die Darstellung von 16α-heterosubstituierten 3-Methoxy-östra-1,3,5(10)-trien-17β-olen 2a - 2e aus 16α-Brom-3-methoxy-östra-1,3,5(10)-trien-17β-ol 1 durch Substitution mit Nucleophilen wird beschrieben. Durch Umwandlung der eingeführten 16β-Substituenten sind weitere Vertreter dieser Verbindungsklasse 2f - 2h zugänglich. Die Verbindungen 2b und 2c werden durch Jones-Oxidation in die 17-Keto-Verbindungen 3b und 3c überführt. Die Konfiguration der Verbindungen wird durch IR- und 1H-NMR-Spektroskopie gesichert.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180319
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  • 97
    Digitale Medien
    Digitale Medien
    The Stobbe Condensation with Substituted Succinic Esters. Part III. A Synthesis of Benzofuran and Indole Derivatives (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 816-822 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Die Stobbe-Kondensation mit substituierten Bernsteinsäureestern. III. Synthese von Benzofuran- und Indol-DerivatenDie Kondensation von 1-Methylpyrrolyl-2-carbaldehyd mit Methyl-bernsteinsäure-dimethylester in Gegenwart von Natriumhydrid ergab überwiegend den entsprechenden E-Halbester 1a. Im Gegensatz dazu führte die Kondensation von 1-Methylpyrrolyl- bzw. Furyl-2-carbaldehyd mit Phenylbernsteinsäure-dimethylester unter Verwendung von Kalium-tert.-butylat oder Natriumhydrid zu einem Stereoisomerengemisch der E- und Z-Halbester. Die Cyclisierung der E-Halbester ergab die entsprechenden Benzofuran- und Indol-Derivate 2, während durch Hydrolyse die E-Dicarbonsäuren 6 entstanden, die zu den entsprechenden Anhydriden umgesetzt wurden.
    Notizen: The condensation of 1-methyl-pyrrolyl-2-carboxaldehyde with dimethyl methyl-succinate in presence of sodium hydride gave predominantly the corresponding E-half ester 1a. However, the condensation of either 1-methyl-pyrrolyl- or furan-2-carboxaldehyde with dimethyl phenylsuccinate using either the potassium t-butoxide or sodium hydride method produced a stereoisomeric mixture of E- and Z-half -esters. Cyclisation of the E-half-esters gave the corresponding benzofuran and indole derivatives 2; whereas their hydrolysis produced the E-dibasic acids 6, which were converted to the corresponding anhydrides 7.
    Zusätzliches Material: 3 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180513
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  • 98
    Digitale Medien
    Digitale Medien
    MO-LCAO-Berechnungen an Polymethinen. IVI. bis III. Mitteilung s. Lit. [1]-[3]. Zum DÄHNEschen Konzept der gekoppelten Polymethine (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 801-815 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: MO-LCAO Calculations on Polymethines. IV Contribution towards DÄHNE'S Conception of Coupled PolymethinesStarting from a quantumchemical characterization of the polymethine π-electron system covered in the previous papers the significance of streptopolymethine sub-structures in more complicated molecular entities has been investigated. In order to relate the electronic structure of a composite system to those of its constituent parts the electronic wave functions are subjected to the configuration analysis. Indices have been employed to evaluate the localizability of the atomic or molecular sub-systems. According to these indices many structures may be considered as being composed from polymethinic, polyenic and aromatic fragments. In the case of the several carbo-and heterocyclic π-systems serious shortcomings of the composite system approach are clearly indicated. Scope and limitation of this model can, however, easily be recognized by application of the simple second order perturbation theory.
    Notizen: Ausgehend von einer quantenchemischen Charakterisierung des Polymethinzustandes, die in den vorangegangenen Arbeiten behandelt wurde, wird die Bedeutung der Streptopolymethin-Teilsysteme für komplizierte molekulare Strukturen untersucht. Um die Elektronenstruktur des zusammengesetzten Systems mit denen der partizipierenden Teilsysteme zu vergleichen, werden die elektronischen Wellenfunktionen der Konfigurationsanalyse unterworfen. Die Lokalisierbarkeit in atomare und molekulare Subsysteme wird durch Indizes bewertet. Danach können zahlreiche Strukturen aus polymethinischen, polyenischen und aromatischen Fragmenten zusammengesetzt gedacht werden. Bei einigen carbo- und heterocyclischen π-Systemen ist das Baukastensystem nur begrenzt anwendbar. Die Anwendungsbreite des Modells kann aber durch Anwendung der einfachen Störungstheorie 2. Ordnung leicht erkannt werden.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180512
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  • 99
    Digitale Medien
    Digitale Medien
    Sydnon-äthylene. I Stereoselektive Darstellung von Sydnon-äthylenen aus Sydnon-aldehyden (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 823-834 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Sydnone Ethylenes. I Stereoselective Synthesis of Sydnone Ethylenes from Sydnone AldehydesSydnones are formylated in 4-position by the VILSMEIER-HAAK reaction. N(3)-Methyl- and N(3)-(p-Anisyl)-sydnone-(4)-carboxaldehyde react stereoselectively to sydnone ethylenes with diethyl ethoxycarbonylmethanephosphonate by HORNER reaction and with arylmethylphosphonium salts by WITTIG reaction in the presence of strong bases. In the latter case, especially in the absence of lithium cations, Z-selectivity is observed which is explained by electronic interaction between the sydnone cyclus and the aromatic substituent of the phosphine ylid in the first step of the reaction. The configuration of the obtained Z- and E-sydnone ethylenes is determined by means of 1H-NMR- and IR-spectra.
    Notizen: Sydnone lassen sich in 4-Position nach VILSMEIER-HAAK formylieren. N(3)-Methyl- und N(3)-(p-Anisyl)-sydnon-(4)-carbaldehyd werden mit Äthoxycarbonylmethan-phosphonsäurediäthylester nach HORNER und mit verschiedenen Arylmethylphosphoniumsalzen nach WITTIG in Gegenwart starker Basen stereoselektiv olefiniert. Im letzteren Fall tritt besonders in Abwesenheit von Lithiumkationen eine Z-Selektivität auf, die auf eine elektronische Wechselwirkung zwischen dem Sydnonring und dem aromatischen Substituenten des Phosphin-ylids im ersten Reaktionsschritt zurückgeführt wird. Die Konfigurationsbestimmung der resultierenden Z- und E-Sydnonäthylene erfolgt an Hand der 1H-NMR- und IR-Spektren.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180514
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  • 100
    Digitale Medien
    Digitale Medien
    Darstellung und Eigenschaften von Pyrazolo[3,2-c]benzo-1,2,4-triazinen und Pyrazolo[3,2-c]pyrido[4,3-e][1,2,4]triazinen (1976)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 318 (1976), S. 835-842 
    Details
    ISSN: 0021-8383
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Synthesis and Properties of Pyrazolo[3,2-c]benzo-1,2,4-triazines and Pyrazolo [3,2-c]pyrido[4,3-e] [1,2,4]triazinesα,β-Unsaturated β-aminonitriles 1 condensate with 2-nitrophenylhydrazine and with 4-hydrazino-3-nitropyridine to yield the corresponding nitriles of β-keto acids 2 and 3, respectively. Bases achieve cyclisation of these compounds to pyrazolo[3,2-c]benzo-1,2,4-triazine-5-oxides 7 and pyrazolo[3,2-c]pyrido[4,3-e] [1,2,4]triazine-5-oxides 8, respectively. The N-oxides are reduced by means of sodium dithionite to the corresponding triazines 9, 10.
    Notizen: α,β-Ungesättigte β-Aminonitrile 1 kondensieren mit 2-Nitrophenylhydra-zin und mit 4-Hydrazino-3-nitropyridin zu Hydrazonen von β-Ketosäurenitrilen 2 bzw. 3. Diese Verbindungen cyclisieren bei der Einwirkung von Basen zu Pyrazolo[3,2-c]benzo-1,2,4-triazin-5-oxiden 7 bzw. Pyrazolo[3,2-c]pyrido[4,3-e] [1,2,4]triazin-5-oxiden 8. Die N-Oxide lassen sich mittels Natriumdithionit zu den entsprechenden Triazinen 9, 10 reduzieren.
    Zusätzliches Material: 4 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/prac.19763180515
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