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  • 1970-1974  (2,378)
  • 1890-1899  (195)
  • Life and Medical Sciences  (2,573)
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  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 631-635 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The patterns of the superficial veins of the cubital region were studied in 536 Indian subjects both living and dead. Three basic pattern types were noted. Type I had a median cubital vein joining the cephalic and basilic veins in the cubital region. Type II had the cephalic vein itself draining into the basilic vein in the cubital region. Type III showed the absence of a direct communication between the cephalic and basilic veins in the cubital region. The median vein of the forearm in these latter cases joined either of the cephalic and the basilic veins (type III A) or after bifurcating into a median cephalic and a median basilic vein joined both these veins (type III B). Type I was found to be the most common pattern (67.5%) followed by type II (19.5%), with types III A and III B accounting for 6% and 6.5% of the cases, respectively. Renaming of the median cubital vein as the oblique cubital vein because of its direction and renaming of the median basilic and lateral basilic veins as medial and lateral cubital veins since they follow the medial and lateral borders of cubital fossa respectively has been suggested.
    Additional Material: 10 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 657-665 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ultrastructure of ependymal cells of the median eminence in young Pacific blacktip reef sharks is described. Three major cell types have been observed. The first type is an irregularly-shaped, electron dense cell with many long microvilli and occasional cilia projecting into the ventricle. A second type contains dense cytoplasmic granules in sizes ranging from 1000-2000 Å, and may be morphologically equivalent to “liquor-contacting neurons” observed in ependymal linings elsewhere. The third type appears very similar to crown cells of saccus vasculosus of this and other species. Cells of the third type possess large, lipid-like inclusions, bulbous projections originating from basal bodies, and prominent smooth endoplasmic reticulum. The crown-like cells are compared to cells of saccus vasculosus of young and adult sharks, and their possible significance is discussed.
    Additional Material: 10 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Following treatment with propylthiouracil, most chondrocytes in the reserve and upper proliferation zones in the tibial epiphyseal plate exhibit degenerate ultrastructural morphology. In the extracellular matrix, sulfated mucopolysaccharide is reduced, matrix vesicles are increased both in number and in size, apatite crystals are present in all zones, and mineralization is enhanced.In post-treatment recovery, chondrocyte degeneration decreases; however, the extracellular matrix is considerably delayed in returning to conditions comparable to those in corresponding controls and this is indicated by the continued presence of apatite crystals in abnormal locations.Chondrocyte degeneration, sulfated mucopolysaccharide, and matrix vesicles, are discussed as they relate to the mineralization process.
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  • 5
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The postnatal growth of the lung was quantitatively investigated in rats aged 1, 4, 7, 10, 13, 21, 44 and 131 days by light and electron microscopic morphometry.Lung volume (VL) increased first directly with body weight (W). After day 10 VL followed the function W0.70. Based on the quantitative findings the postnatal lung growth could be divided into three phases.1Lung expansion (up to day 4): Lung volume increase resulted almost exclusively from an 87% enlargement of the existing air spaces.2Tissue proliferation (day 4 to 13): All tissue compartments showed a pronounced mass increase, followed by a high gain in capillary volume. Alveolar and capillary surface areas (Sa, Sc) developed rapidly due to subdivision of the primitive air sacs.3Equilibrated growth (third week to adult age): An initial period of redistribution of tissue mass with septal lengthening and further rapid increase in Sa and Sc was followed by proportionate alveolar growth. In the adult further lengthening of the interalveolar septa or continued alveolar formation could not be excluded.During the period of fundamental internal remodelling of the lung, its function, as determined by the morphometric pulmonary diffusing capacity, was not impaired.
    Additional Material: 9 Ill.
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  • 6
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Whole-body autoradiograms were prepared from intact and hypophysectomized (Hypox) rats after receiving 125I-HGH iv. In addition, some hypox rats received unlabeled HGH or ACTH six minutes before receiving the 125I-HGH. Hypox rats had greater concentrations of radioactive material in the renal cortex, adrenal cortex, liver and submandibular gland than was present in blood. Pretreatment with ACTH increased the radioactive material in the inner zones of the adrenal cortex; liver and renal cortex contained more radioactive material than blood; and the submandibular gland contained an amount equal to that in blood. Pretreatment with unlabeled HGH greatly suppressed uptake of radioactivity in liver and adrenal cortex and slightly increased the uptake in the renal cortex. Radioactivity could not be detected in the renal medulla or urine of any of the rats. No concentration of radioactive material greater than that seen in blood was present in any other organ or tissue in any of the groups. In the intact rats, the kidney and the adrenal cortex had the greatest concentrations of radioactivity, while the concentration in the liver was equal to that in blood. Autoradiograms were also prepared from sections from untreated hypox rats that were dipped in 125I-HGH solutions. These confirmed the presence of binding sites in the adrenal cortex and liver for 125I-HGH. No binding of radioactive material was seen in the kidney.
    Additional Material: 4 Ill.
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  • 7
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ultrastructure of articular cartilage of the femoral head was examined in growing male mice of strain C57Bl fed diets containing supplements of 25 or 40% corn oil for periods of 10 days, 2 and 4 weeks and 2 and 3 months. The ration containing 25% corn oil did not produce conspicuous effects. The ration containing 40% corn oil exerted a slight stimulation on the size, the ER, and the mitochondria of the articular chondrocytes. The findings are consistent with the long range effects of oil-enriched diets on the knee joints of mice and in particular with the failure of such diets to promote the development of osteoarthrosis in mice of strain C57Bl. The results are discussed in relation to earlier observations of the injurious action of diets containing comparable amounts of saturated fat.
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  • 8
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Each of the major coronary arteries of 25 fresh sheep hearts was injected with a different colored barium gelatin mass. Histologic sections were made of the AV node and His bundle in nine hearts. The blood supply to this region was traced radiographically, photographically and histologically. X-rays of the upper ventricular septum were taken before and after coronary injection to demonstrate an os cordis.The sinus node is always supplied by a branch of the right coronary artery. The crux of the heart, and subsequently the AV node, is always supplied by the circumflex artery. The unbranched His bundle, unusually long in sheep, receives a dual blood supply from both the anterior septal branches and the AV node artery. The proximal part of the left and right bundle branches is supplied by the anterior septal branches in the majority of hearts. Intercoronary anastomoses are present in the majority of hearts, particularly in the upper ventricular septum.An os cordis, deep in the atrial septum and directly adjacent to the AV node, was found in all 25 hearts. Occasionally, a second bone was found in the anterior part of the left atrioventricular ring.
    Additional Material: 5 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 241-251 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The postnatal development of the ovary in the bank vole and vole was investigated in order to determine whether the earlier onset of puberty in the vole coincides with a difference in the speed of gonadal development during the immature period in the two species.The ovarian development differed in three respects: in the vole 4-10% of the germ cells are still oogonia when the animal is born, while in the bank vole oocytogenesis is completed during the embryonic period. Follicles develop earlier and more rapidly in the vole than in the bank vole. The early appearance of fluid accumulation in the follicles and the formation of “fluid sacs” in the vole ovary is characteristic.
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 273-284 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Extensive subsurface cisterns were commonly found beneath the apposed plasmalemmas of adjoining hepatocytes in young and adult mice. The cisterns were of two types: (1) flat cisterns, often with ribosomes on their deep surface, and (2) flattened, highly fenestrated smooth surfaced saccules, some of which were in continuity with smooth endoplasmic reticulum. Despite their frequent occurrence, the subsurface cisterns were always absent from the regions of gap or tight junctions, as well as from the periphery of bile canaliculi and cell surfaces bordering the space of Disse. The function of these cisterns remains undetermined.
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  • 11
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 285-296 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The fine structural appearance of eight spontaneously polyspermic rabbit zygotes was studied. The zygotes were considered polyspermic only after they met all criteria that excluded other possibilities of the trinucleate state. The presence of accessory male pronuclei, with varying degrees of disintegration of their chromatin in zygotes of similar age, suggests that refertilization can occur during an interval of several hours after penetration of the primary sperm. All of the polyspermic zygotes contained cortical granules intermittently beneath the vitelline (plasma) membrane. One zygote possessed cortical granule-like structures with ill-defined or no limiting membrane. Formation of enveloping membranes around the incorporated accessory sperm head was precocious since it occurred prior to disintegration of the chromatin. Advanced stages of accessory pronuclei morphologically resembled the primary pronuclei in the same zygote. In seven out of eight zygotes the accessory male pronucleus was separated from the apposing male and female pronuclei. It was concluded that although the fully expanded accessory male pronucleus is similar to the pronuclei of monospermic fertilization, the temporal events of nuclear envelope formation were disturbed.
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  • 12
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 331-341 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The numbers and diameters of nerve fibers were determined for the first time for all interganglionic rami of the sympathetic chain of the frog. The number of myelinated fibers ranged from 57 to 263 and was generally highest in the anterior portion (207) and lowest at the posterior end (57) of the chain. The exception was between the fourth and fifth ganglia where the middle splanchnic nerves arise  -  the number of myelinated fibers was highest here (263). Unmyelinated fiber counts were similar throughout the chain (417-814) except above and below the first sympathetic ganglion (7325 and 3026, respectively), and at the level where the middle splanchnic nerves arise (3780). Unmyelinated fibers constituted 75-97% of the fibers of the chain. The myelinated fibers ranged in diameter from 0.5 to 9.0 μ, 75% of them measuring between 1.5 and 3.0 μ. The diameter range for unmyelinated fibers was 0.1 to 5.0 μ with 78% being 0.1 to 1.0 μ.
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  • 13
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 343-359 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The processes of myogenesis and elastogenesis are studied under the electron microscope in developing rat lungs, throughout the 15th to the 21st days of the gestation period. Myogenesis follows bronchial development and stops at the beginning of the alveolar zone, at the primitive respiratory bronchiole level. Elastogenesis appears at the periphery of the myoblasts during their differentiation. Thin myofilaments only are observed within myoblasts and their formation precedes that of dense bodies.Primitive respiratory bronchioles are visible on the 19th day and are characterized by an early elastogenesis carried out by fibroblasts. At this stage there are no elastic fibers around the alveolar tubules. Then (20th and 21st days) elastogenesis spreads throughout the alveolar zone, accompanying the alveolization process. Peculiar morphological characteristics of the pulmonary fibroblast are underlined. In relation to both muscular cells and fibroblasts the fine structural features of the rat pulmonary elastogenesis are identical to those previously described in other organs. Myoblasts and fibroblasts probably originate from the same primitive mesenchymal cell. Their differentiation depends on the zone where they are located. The relations between connective tissue and epithelial cell differentiation suggest a control of lung development by means of reciprocal induction processes.
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  • 14
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 447-451 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The number and spatial relations of muscle spindles in the extensor indicis have been determined. Approximately forty spindles lie adjacent to the motor end plate zone dispersed rather equally through this area of the muscle with a modest increase in density among the distally originating fibers. A study of the entire innervation pattern of this muscle has also been completed.These findings have greatly facilitated the isolation of spindles for electron microscopic study and attempts to perform in vivo recording from the sensory nerves of muscle spindles in this laboratory. It is now possible, with the aid of suitable magnification and stimulating and recording devices, to more rapidly find muscle spindles relative to the gross innervation and the easily located motor end plate zone.
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  • 15
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Human muscle spindles are isolated from muscle biopsies of Extensor Indicis. A spindle rich portion of muscle is removed, placed into a modified Kreb's solution and microdissected for spindles. Intramuscular nerves and blood vessels provide helpful locating guides. Spindles can be dissected free of extrafusal muscle with an adequate length of nerve for in vitro recording. Another portion of muscle is stretched and placed into a 5% glutaraldehyde fixative in 0.1 M cacodylate buffer. Spindles are dissected free, postfixed, dehydrated, stained, and then studied with the light microscope while in liquid Epon. The equatorial regions are identified, then removed and embedded for examination using the electron microscope. This is the first successful total isolation of viable human spindles. The combined procedures allow correlation of recordings from the primary sensory endings with the fine structure of spindles from normal persons and from patients with neuromuscular disorders.
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  • 16
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 477-480 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The functions of the normal semispinalis capitis and splenius capitis muscles of fifteen subjects were evaluated electromyographically with bipolar fine-wire electrodes. The voltage-output data were integrated and analyzed by computer and showed that the main function of semispinalis capitis is limited to extension of the head. However, splenius capitis both extends the head and rotates it to its own side.
    Additional Material: 3 Ill.
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  • 17
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 491-496 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Electron microscopy of the turtle sinus venosus shows an unusual neuron soma which is immediately surrounded by myocardial cells so as to form a somato-muscular complex. Studies of 36 sections cut through this neuron soma indicate that 27.4% of the somal surface studied is directly covered by cardiac muscle cells without any intervening basal lamina. Similarly, 18.8% of the somal surface studied is in contact with unmyelinated axons which at places make typical axosomatic synapses. A coupling of peripheral cisterns of the sarcoplasmic reticulum and the sarcolemma exists at the somato-muscular contiguity as well as at the border between cardiac muscle cells. It is suggested that neural influences upon the pacemaking activity of the turtle heart sinus can well be exerted through the somato-muscular pathway. Additionally, an axon which is presynaptic to the neuron soma has been observed to be simultaneously in a synaptic relation with a cardiac muscle cell; a remarkable deviation from the classical picture of the efferent nervous outflow to the heart.
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  • 18
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 19
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Keratinization or mucification of the epithelium of the rat vagina is related to the hormonal state of the animal. During the normal cycle and after the administration of exogenous hormones (estrogen and progestin) to spayed animals, the surface characteristics and topography of the vaginal epithelium were studied with the scanning electron microscope. During estrus and under the influence of estrogen, the superficial cells were keratinized, overlap each other like shingles, and are continuously sloughed off. Like the surface of other keratinizing epithelia, theirs has a characteristic microridge pattern. In ovariectomized animals, the apical surface is covered with microvilli instead of microridges, and the cells resemble hexagonally shaped units, tightly bound instead of overlapping each other. At the boundary between the cells, a ridge demarcates the cells. The surface configurations of progestin-treated, progestin plus estrogen-treated, and diestrous animals are the same as in spayed animals.
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  • 20
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 539-549 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Chronic hyperthyroidism was induced in radiothyroidectomized adult albino rats by feeding a diet of 0.3-0.4% desiccated thyroid for four to ten weeks. The left ventricle from control and hyperthyroid animals was examined with the electron microscope after perfusion fixation with 3% phosphate buffered glutaraldehyde and postfixation in 1% osmium tetroxide. No differences were discerned in the appearance of the Golgi zone, glycogen, lipid, lysosomes, sarcoplasmic reticulum, or the sarcomere ultrastructure of the ventricle from hyperthyroid animals compared with untreated animals. Changes were noted in the mitochondria. These included marked hypertrophy without increase in numbers and localized areas of vacuolization and disorientation of the cristae. Apparently these changes are reversible since the ventricular mitochondria of previously hyperthyroid animals allowed to return to a euthyroid state were indistinguishable from those seen in the control group.
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  • 21
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 567-585 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The endocrine pancreas of the Coturnix quail consists of two major islet configurations. Islets containing B and D cells are found in all four lobes of the pancreas, but islets consisting of A and D cells occur with regularity only in the third and splenic lobes. Pancreatic islets comprise only a small percentage of the tissue volume in the ventral, dorsal and third lobes. In the splenic lobe, however, one or more A islets surrounded by numerous small B islets may constitute more than 50% of the total cellular mass.Secretory granules of the B cells are aldehyde fuchsin-positive and show three distinct profiles at the ultrastructural level. The PTAH-positive A granules are usually round or teardrop shaped and are of uniform electron density. D cells are argyrophilic; their secretory granules are of heterogeneous densities. These cells are located at the peripheries of the B islets, but are freely dispersed in the A islets. At the electron microscopic level, Type IV cells, previously not reported in avian islets, are found mainly in the A islets of this species. This unusual cell type contains granules of differing densities, but, unlike those of the D cell, they are often rod-shaped and biconcave in profile.Because of the distinct segregation of islet types, and the peculiar arrangement of the D and Type IV cells within the two kinds of islets, it is suggested that the Japanese quail may serve as a model for investigations of avian islet function.
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  • 22
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 599-615 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The intercalated discs of the myocardium from the active and hibernating bat hearts were investigated by means of electron microscopy and use of lanthanum and horseradish peroxidase as tracers. The discs are composed of four zones: intermediate junctions, desmosomes, nexuses, and undifferentiated areas. Of particular interest are the two different types of nexuses. Nexus I without lanthanum displays a 150 Å overall width and an apparent 80 Å intercellular space, ranges from 0.5 to 4.0 μ in length, and is seen in the longitudinal segments of the intercalated disc. With application of lanthanum, however, nexus I shows that the tracer has penetrated a 20 Å gap junction and resembles nexus II. Nexus II with and without lanthanum has a 200 Å overall width and a gap junction of about 20 Å, is generally less than 0.3 μ in length, and is found on the transverse or oblique segment of the intercalated disc. Both nexuses I and II seem to block the passage of peroxidase. The plasma membranes of nexus I may have a different molecular organization from those in nexus II as reflected by their contrasting response to fixation and/or staining. Combinations of the various junctions show that the zones of adhesions (intermediate junctions and desmosomes) are adjacent to the regions of possible lowered resistance (nexus I and II). These findings suggest that adhesion sites insure the proper connection and functioning of the nexuses and support the electrical observations that the heart forms a “physiological syncytium”.
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  • 23
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 623-630 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: It has often been reported that facial proportions remain constant throughout the fetal period. Such conclusions, however, have been based largely on the erroneous assumption that two dimensions are growing isometrically if one bears a statistically significant linear relation to the the other. In order to test the hypothesis that proportion is independent of time, sagittal histologic sections from 32 human fetuses (12-25 weeks) were analyzed cephalometrically. The linear regression on head length (HL) and the associated coefficient of correlation were calculated for each of a variety of craniofacial measures. In addition, all linear dimensions were transformed so that the size of the anterior cranial base was held constant throughout the series. It was assumed that if shape be constant, all Y-intercepts should be zero, and angular and transformed linear dimensions should show no statistically significant linear correlation with HL. These three criteria were met uniformly by facial and anterior cranial base dimensions, but not by measurements which involved the posterior cranial base. It is concluded, therefore, that in the sagittal plane the second trimester mandible, midface, and anterior cranial base grow isometrically, while the posterior cranial base becomes relatively smaller.
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  • 24
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 637-645 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Macroscopic and microscopic examination of adipose tissue was carried out in a series of 20 human fetuses, ranging in weight from 380-3032 gm, in an attempt to identify all areas of brown (multilocular) fat development and growth. Brown fat distribution in the human fetus takes the form of a highcollared vest affording coverage to the cervical, thoracic and abdominal viscera. Much of this fat lies deep within the body immediately outside the pleural and peritoneal membranes. the remainder overlies or borders muscles of the shoulder girdle and neck as distinct brown fat deposits deep to the subcutaneous layer of white (unilocular) fat. All brown fat bodies contain unilocular cells but they occur in very small numbers in the brown fat bodies of the posterior cervical triangle, anterior mediastinum and perirenal and suprailiac regions. Brown fat bodies usually develop along the course of large blood vessels and several of them develop direct vascular connections with the liver and kidneys. The total weight of fetal brown fat increases at a rate directly proportional to that of the liver and kidneys up to 2134 gm body weight and to that of the liver beyond this weight.
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  • 25
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The intramural arteries, arterioles and capillaries of the hearts of 23 crossbred pigs, six months old, of Yorkshire and Swedish landrace were presented.The vascular pattern was basically the same in both the ventricular walls. Large branches of two types emerged from the extramural arteries and traversed the myocardial wall, terminating in the subendocardial zone. The largest vessels supplied the papillary muscles and trabeculae carneae. The terminals of these branches formed the subendocardial anastomotic network. No other anastomoses were observed in the ventricular walls. The capillaries had a course parallel to the muscle fibers and anastomosed freely. Most of the interventricular septum was supplied by branches from both the left and the right descending arteries. Only a minor part of the septum was supplied by the anterior and posterior septal arteries.The ventricular vascular pattern of the pig was found to be very similar to that of the human heart. It was concluded that the pig, in contrast to the dog, has ideal attributes for comparative cardiovascular research in man.
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  • 26
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 667-669 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Projection from medial occipital cortex (area OB) to the nucleus of Darkschewitsch is demonstrated in six Macaca mulatta hemispheres by the technique of Fink and Heimer. Degeneration was present as well in the lateral pons, nucleus lateralis dorsalis, nucleus lateralis posterior, lateral pulvinar and nucleus parafascicularis. Centrum medianum, dorsal lateral geniculate body and interstitial nucleus of Cajal were spared.
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  • 27
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The seminal vesicle secretes a variety of substances into semen, ranging from small molecules to enzymes. The formation of protein components of the seminal vesicle secretion was studied in male rats following an injection of leucine-3H. Samples of seminal vesicle were fixed and prepared for light and electron microscope radioautography at intervals ranging between four minutes and two hours after the injection. In specimens prepared four minutes after administration of the precursor, the majority of silver grains overlay the rough endoplasmic reticulum. At subsequent intervals, the proportion of grains over the endoplasmic reticulum declined, and peaks of labeling were observed sequentially over the Golgi apparatus and over secretory vacuoles. The maximal labeling of the Golgi apparatus was attained between 10 and 30 minutes after the injection. Secretory vacuoles acquired their greatest radioactivity 30 minutes following administration of the leucine-3H. Labeled secretions began to appear in the lumen 30 minutes after the injection, and they became heavily labeled by one hour. The results suggest that secretory proteins are synthesized in the rough endoplasmic reticulum and transported rapidly to the Golgi apparatus where secretory vacuoles are formed. The secretory vacuoles migrate to the apical ends of the cells and discharge their contents into the lumen. The transport and release of secretory proteins in the seminal vesicle is unusually rapid and exceeds the rate in many other protein secreting cells, including that of the ventral prostate.
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  • 28
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Proteins, including enzymes such as acid phosphatase, are among a variety of substances secreted into semen by the prostate gland. The formation, intracellular transport, and discharge of protein components of prostatic secretion were studied in the rat ventral prostate following an injection of leucine-3H. Samples were prepared for light and electron microscope radioautography at intervals ranging from four minutes to two hours after the injection. In samples prepared four or ten minutes after administration of the precursor, most of the silver grains overlay the rough endoplasmic reticulum. Beginning 30 minutes after the injection, while label associated with the endoplasmic reticulum was declining, the proportion of grains over the Golgi apparatus began to increase, reaching a maximum in one-hour samples. Secretory vacuoles at the apical ends of the cells became heavily labeled two hours after administration of the leucine-3H. Labeling of secretions in the lumen of the prostatic alveoli was observed in samples taken two hours after the injection. These results indicate that secretory proteins in the prostate are synthesized in the rough endoplasmic reticulum, transported to the Golgi apparatus, and packaged into secretory vacuoles, which move to the apical ends of the cells and release their contents to the lumen. Additional analysis of the pattern of labeling of different elements of the Golgi apparatus suggests that some protein is transported sequentially from Golgi vesicles to stacks of cisternae and finally into Golgi vacuoles. Radioactive secretory proteins move through prostatic cells more slowly than through the seminal vesicle epithelium of the same animals. The main mode of protein secretion in the prostate appears to be a merocrine type, since apical protrusions such as have been suggested to participate in an apocrine form of secretion were observed infrequently and did not become heavily labeled.
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  • 29
    Electronic Resource
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 597-603 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The minimum period of uterine exposure required by ejaculated boar spermatozoa as a preliminary to rapid capacitation has been determined after natural or surgical deposition of sperm samples directly into the uterine lumen. Twenty-four oestrous gilts were mated or inseminated close to the time of ovulation, and 15, 30, 45 or 60 minutes later, the Fallopian tubes were separated from the uterine cornua. The tubes were flushed at pre-arranged intervals during a second intervention, and the proportion of eggs penetrated and activated examined by phase-contrast microscopy.On the basis of 166 eggs recovered from eighteen mated gilts, a period of uterine exposure as brief as 30 minutes, when followed by a tubal residence of approximately three hours, permitted 30.3% of the eggs to be activated; this proportion increased to 51.6% and 60.5% if the tubes were isolated 45 or 60 minutes, respectively, after mating (p 〈 0.001), as did the mean number of spermatozoa associated with the eggs. When the cornua were separated from the tubes 15 minutes after semen deposition into the uterus of six animals, 11.3% of 62 eggs were fertilized during the ensuing three and one half hours, but very few spermatozoa had reached and/or attached to the eggs in this group.It is concluded that a population of boar spermatozoa potentially capable of effecting fertilization may enter the tubes within 15 to 30 minutes of mating near the time of ovulation, and that such vanguard spermatozoa can activate a proportion of the eggs within a further two to three hours. Thus, from a temporal point of view, the major components of the capacitation process in oestrous pigs are inferred to take place in the Fallopian tubes.
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  • 30
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 645-661 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Five different proteolytic enzymes, trypsin, pronase, collagenase, papain and ficin, were tested for their ability to liberate mononucleated myogenic cells from adult rat muscle. Fragments of leg and thigh muscle from 350-400 gm rats were incubated with enzyme for one hour and mononucleated cells were separated from the partially digested fragments by centrifugation. Myogenic capacity of the isolated cells was tested in culture using procedures known to support differentiation of embryonic rat muscle. Although all the enzymes released viable cells from the muscle, myogenesis in vitro was obtained only from cells liberated by trypsin or pronase. The other three enzymes released fibroblasts, macrophages and fat cells but no presumptive myoblasts. Light and electron microscopic examination of the digested muscle revealed that the enzymatic release of myogenic cells is dependent upon removal of the basement lamina surrounding the fibers. Trypsin and pronase dissolve the basement lamina, whereas collagenase, papain or ficin do not. These findings demonstrate that a population of myogenic stem cells exists in fully mature, non-regenerating adult muscle. The frequency of these cells and the conditions required for their release suggest that they are identical with the muscle satellite cells.
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  • 31
    Electronic Resource
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 681-686 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Collapse of the left lung in adult mice is followed by an increased mitotic incidence (MI) in the right lung which persists for approximately four days after operation. This compensatory increase in MI does not occur if the left thoracic cavity is packed with an implant of cotton wool which prevents hyperinflation of the right lung. The rate of incorporation of labelled thymidine per unit of DNA (RIT) is higher in the right than in the left lung of unoperated animals but after collapse of the left lung there is a reduction in the ratio of right to left in respect of RIT. These differences in RIT do not appear to correspond to changes in the rate at which cells enter DNA synthesis and it is suggested that they are due to differences in vascularisation between the right and left lungs. The compensatory increase in MI which follows unilateral collapse is not due to loss of tissue mass, to tissue damage or to the direct effects of the increased physiological load placed upon the remaining functional tissue. It is suggested that hyperinflation of the right lung causes changes in the rate of blood flow through that part of the organ and that, in consequence, there is a change in the local concentration of metabolites including those whose function is to regulate the mitotic rate.
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  • 32
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 229-241 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Banded spindle-shaped structures consisting of packed cylindrical units were observed among the typical collagen fibrils in the notochord sheath or in the intercellular space between notochord cells of Salmo irideus larvae. The banded spindle-shaped structures showed a regular periodicity ranging from 750-1000 Å and cylindrical structures which appear to be packed in hexagonal arrays so that six cylinders surrounded a central cylinder. Both banded and cylindrical structures appeared to be the same bodies in three dimensions. These banded structures may originate from surrounding collagen fibrils.On the other hand, comb-shaped structures were found between the elastica externa and the collagen fibrils of the notochord sheath in newly hatched S. irideus larvae and in fry. The width of the structures was about 0.25 Å in the widest part. The banding showed a regular periodicity ranging from 500-600 Å. These structures may play a role in adhesion of the elastica externa to the underlying collagen fibrils of the notochord sheath.
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  • 33
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 289-290 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Ultrasound studies of dorsalis pedis artery in 400 feet showed the artery to be absent in 2.25%, i.e., much less frequently than it was commonly claimed. Clearer understanding of this variation and its frequency may facilitate the diagnosis of peripheral circulatory disease.
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  • 34
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 291-527 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 35
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Leydig cells appear in the hamster testis between 12 and 13 days gestation. The cells are round to oval, with prominent lipid droplets, abundant smooth endoplasmic reticulum, large mitochondria with tubular cristae and well developed Golgi complexes. Cells of this type are found in pairs and groups around interstitial blood vessels during the last three days of gestation and up to the fourth day after birth, when regressive changes begin to appear. During the second postnatal week, most cells in the interstitial regions are undifferentiated, with only a few scattered partially differentiated Leydig cells remaining. The time during which fully differentiated Leydig cells are present encompasses the period of sexual differentiation of the reproductive ducts and the critical period for differentiation of sexual behavior.
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  • 36
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The forebrain of the isolated central nervous system of frogs was fixed by freeze substitution and studied with the electron microscope. The extracellular space (ECS) of brains kept for 15-20 min in a physiological salt solution at room temperature varied from an appreciable to a negligible one. In electron micrographs exhibiting a large ECS the tissue elements had a uniform electron density. The EMs with little space featured in some instances a moderate swelling of presynaptic terminals and other tissue elements. Brains kept in a cooled medium or a salt solution with MgCl2 added exhibited invariably an abundant ECS. Treating the brain with a 100 mM KCl solution 5-90 sec before freezing yielded EMs with a contracted ECS and swollen tissue elements, many of which could be identified as dendritic spines. This effect of KCl was in many experiments prevented by bathing the brain in a salt solution containing 10 mM MgCl2 or in a Ca-free solution.
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  • 37
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The influence of different estrogen-progesterone ratios on DNA synthesis in the rat uterus was investigated. Ovariectomized rats were injected subcutaneously daily for three days with either oil, 1 μg estradiol-17β dipropionate or estradiol and 1, 5, 10 or 15 mg progesterone. Tritiated thymidine was administered one hour prior to necropsy. Thymidine indices were determine for both the luminal and glandular uterine epithelia while the total number of labeled nuclei in the stroma was ascertained. In all tissues studied, significantly more nuclei from uteri of rats given only estrogen replicated DNA than from those of the oil-treated controls. While concurrent treatment with estradiol and 1 or 15 mg progesterone did not statistically alter the extent of thymidine incorporation in the luminal epithelium and stroma from that observed following estrogen alone, 5 or 10 mg progesterone given with estrogen significantly suppressed the labeling activity in the luminal epithelium and stroma from that of the estrogen-treated rats. However, the thymidine indices of the glandular epithelium from uteri of rats injected with all combinations of both hormones were significantly lower than that from uteri of estrogen-treated rats. These data indicate that the estrogen-progesterone ratio is important in regulating cell turnover in the luminal epithelium and stroma of the rat uterus but not in glandular epithelium.
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  • 38
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Light microscopic studies using a battery of basic dye stains combined with sialidase and hyaluronidase digestions indicated that the extensive basophilia of the maternal surface of the placental syncytium largely results from the presence of a non-sulfated mucosubstance specifically identified as hyaluronic acid. Ultrastructural examination of dialyzed iron (DI) stained specimens revealed that DI-positive filaments observed along the syncytial surface were removed by hyaluronidase digestion. Staining with the lectins, Concanavalin A or lentil bean hemagglutinin produced an intense and periodic pattern of staining that was not enzyme labile. Incubation of tissue sections in the enzyme solutions or control buffers allowed the lectins to penetrate the syncytial plasma membrane and stain material within the endoplasmic reticulum presumed to be human chorionic gonadotropin. The maternal surface exhibited essentially no reactivity for acid phosphatase but showed strong alkaline phosphatase activity with a periodic staining pattern. With each of the techniques used there was variability in the intensity of staining in different regions along the maternal surface, suggesting that functionally different zones may be identified cytochemically. Only minor differences were observed in the cytochemical reactivity of early compared with term placenta.
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  • 39
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 27-55 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In an effort to elucidate various aspects involving the initiation of development, the morphogenesis of the spontaneously activated egg of the golden hamster was examined at the light and electron microscopic levels of observation. Spontaneous activation of the unfertilized hamster egg occurs upon prolonged incubation within the oviduct, i.e., aging in vivo, and may include the formation of the second polar body and the development of one or several pronuclei. In many instances the activated egg resembles the inseminated ovum at the pronuclear stage of fertilization. Occasionally the activated egg will divide and yields a structure which is morphologically similar to the two-cell stage. Development beyond the two-cell stage was not observed. Even though a number of events exhibited by the aging hamster egg mimic those of the fertilized, many are indicative of cellular degeneration. Such processes include, for example, the aggregation of organelles into fairly homogeneous clusters, the budding of portions of the cortex of the egg containing cortical granules into the perivitelline space, the accumulation of vesicles within the ooplasm and the structural modification of microvilli. All activated eggs, at every period investigated (6 to 66 hours post-ovulation), contained cortical granules.
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  • 40
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A parental (CBAT6T6) lymph node cell suspension was injected into the hind footpad of F1 (CBA × C57BLKs) recipients. The resulting increase in the recipient's popliteal lymph node weight was linearly related on double log plots to the number of parental lymph node cells injected. The node weight response was biphasic including an initial rise, a maximum weight gain at seven to nine days and a gradual decline to normal weight. When the long-lived small lymphocyte population of the donor was labeled with 3H-thymidine, the location, morphology and mitotic activity of labeled cells was followed by radioautography. These cells were most frequently observed in the mid- and deep cortex and the medullary cords of the host node. Very few labeled blast cells were observed in sections or smears and radioautographs of chromosome spreads confirmed the infrequency of donor long-lived small lymphocyte transformation and proliferation. Of the proliferating cells in the host node at the peak of the response, 60-85% were of host origin. These observations and others are discussed, and it is proposed that the host short-lived small lymphocyte accounts for the majority of mitotic cells in the node at the peak of the response.
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  • 41
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Study of the caudal cochlear nucleus of the cat confirms the cochlear origin of synaptic terminals, identified in correlated rapid Golgi and electron microscopic preparations of the octopus cell area (OCA) and the dorsal cochlear nucleus (DCN) in normal cats. Type 1 and type 2 endings on octopus cell somas and basal dendrites, as well as type 1 and type 1a endings of the outer DCN, degenerate following complete ipsilateral cochlear ablations and short survival periods (12, 24, 48, 96 hours). Two distinct patterns of synaptic degeneration occur after short survival times; “dense degeneration” occurs in type 1 endings on octopus cells and several endings of the DCN. Dense terminals that contain tightly packed, but intact vesicles, occur most frequently after a 48-hour survival period. A second type of degeneration, called “flocculent degeneration” occurs in type 1 and type 2 endings of the OCA and in type 1 and type 1a DCN terminals. Between 12 and 48 hours after ablation, the flocculent degeneration involves a continuous breakdown of organelles. Evidence for transneuronal degeneration of octopus cells and DCN granule cells is presented.
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  • 42
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    The @Anatomical Record 179 (1974), S. 517-526 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Some aspects of the basic histological features of the thymus are still not adequately known. The architecture of the heterogeneous organ, like the thymus, can be revealed by a tridimensional reconstruction only. We carried out such reconstruction of the cortex, medulla and network of interlobular septa of the rat thymus. The serial sections of a 10-week-old and of a 5-day-old thymus were projected on a cardboard of a thickness proportional to the magnification of the projection. The outlines of the three studied components were traced and cut off. The superposition of the similar cut-offs yielded a model of each of the three thymic components. The models demonstrated that the current description of the organ is not thoroughly realistic. It was found that there exists bridges of cortex crossing the medulla, whereas buds of medulla are present in the area generally occupied by the cortex. The relationship between the medulla and the cortex is more intricate than currently described. The results revealed that the interlobular septa do not form a network of more or less regular walls designed to divide a lobe into comparable lobules. Instead, this network is irregular, being related to the pathway of the main intrathymic blood vessels.
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  • 43
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The purpose of this investigation was to study the fine structure of pulpal capillaries located in the odontoblastic layer and immediate subjacent zone. The observations were from first molars of white mice sacrificed at five day intervals from 25-90 days. Both capillaries and small vessels with an incomplete smooth muscular coating appeared in the zone subjacent to the odontoblastic layer from 25-60 days. At the same time, capillaries which exhibited intracellular fenestrations in the endothelial wall were located within the odontoblastic layer.From 50-90 days, the capillaries among odontoblasts, especially at the pulpal horns, appeared close to the predentinal surface, and an isolated capillary appeared to extend into predentin and run parallel to the outer surface of the odontoblastic layer for a short distance. At these ages, the capillaries subjacent to the odontoblastic layer also exhibited fenestrations along the thin endothelial walls similar to those observed at earlier ages in capillaries among odontoblasts.
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  • 44
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 1-1 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 45
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Innervation to muscles of the feline perineum was examined by gross dissection of the sacral nerve plexus and quantitation of efferent and afferent myelinated fibers in selected nerves derived from the plexus. In addition, distribution of muscle fiber sizes and muscle spindle content were determined for muscles innervated by the nerves studied.Efferent myelinated fiber populations were bimodal in nerves innervating muscles with many spindles and unimodal in nerves innervating muscles in which few or no spindles were observed. Coccygeus and levator ani muscles had similar numbers of muscle spindles, but the spindles were different in the two muscles based on afferent innervation. In both coccygeous and external anal sphincter muscles, primary spindle endings must be associated with relatively small afferent nerve fibers. The pelvic urethra received more large myelinated afferent fibers than the penis. The three divisions of the external anal sphincter muscle had three distinct populations of muscle fibers, based on size distribution. The homologous bulbospongiosus and constrictor vulvae muscles had different populations of muscle fibers.
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  • 46
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Three groups of mice were standardized to a light-dark cycle with light from 0600 to 1800. One group was fed ad lib; but the other two had access to food for only four hours a day, one during the first part of the light phase and the other beginning at its middle. Two other groups were subjected to a reversed light-dark cycle (light from 1800 to 0600); one of these had access to food for four hours during the first part of the dark phase and the other for four hours beginning at its middle. All the mice previously had been adjusted gradually over a three-week period to these feeding schedules, and then they were maintained on the precise routine described for an additional two weeks. After standardization was completed, subgroups of mice were killed at three-hour intervals over a single 24-hour period. Corneas were removed and prepared, and the mitotic index in the epithelium was evaluated.In all five groups a high-amplitude circadian rhythm was found for the mitotic index, but in all cases this rhythm remained synchronized to the light-dark cycle; only small changes in the phasing of the rhythm resulted from the restricted feeding. These results are contrary to what has been found for a number of other rhythmic variables which do synchronize to such feeding schedules.The findings dispel the misconception that all body functions react in the same fashion to different synchronizors and emphasize that one must not generalize about the effects of feeding or lighting.
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  • 47
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 77-98 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In order to investigate the postnatal growth of the gas exchange apparatus, the lungs of rats aged 1, 4, 7, 10, 13, and 21 days were fixed by intra-tracheal instillation of glutaraldehyde. The analysis and interpretation of the morphological changes observed by light and electron microscopy were based on the results of previous morphometric and autoradiographic studies performed on the same material.The newborn rat has no alveoli, but breathes with smooth walled air channels and saccules, which correspond to the prospective alveolar ducts and alveolar sacs, respectively. The bulk of alveoli are formed between days 4 and 13 by a rapid outgrowth of secondary septa from the primary septa present at birth. The arrangement of elastic fibers during this period suggests that these may play a role in septal outgrowth. Based on ultrastructural observations a model is described for the capillarisation of the secondary septa. Some evidence is given that alveoli may also be formed by outpouchings in the walls of terminal bronchioles.Primary and secondary septa have initially an immature appearance. They both show an apparently double capillary network, whereas the mature interalveolar septum is just wide enough to accommodate a single capillary. Possible mechanisms for this structural transformation which occurs within three weeks after birth are discussed.
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  • 48
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The fathead minnow, Pimephales promelas (Rafinesque), has been laboratory bred and the early embryos staged and described. At 23°C the embryo requires 33 hours to reach the 13-somite stage. This period of early embryonic development has been divided into 12 stages. The description of each of these stages is accompanied by photographs.
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  • 49
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 50
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 111-135 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The surface topography of palatal shelves was examined by scanning electron microscopy prior to and during secondary palate formation in 72 therapeutically aborted human embryos and fetuses ranging in age from 37 days to 12 weeks (post-fertilization). Alterations in epithelial surface appearance were observed in the prospective region of fusion prior to contact between the shelves. First seen as an elliptical area along the anterior portion of the presumptive medial edge, a zone of alteration spread progressively along the anterior four-fifths of the medial edge prior to shelf contact, and continued along the posterior one-fifth of the shelf as fusion proceeded. The altered zone eventually extended onto the oral surface in the middle of the shelf but was restricted to a narrow zone along the medial edge posteriorly. Initially characterized by elongation and “intertwining” of superficial cells, alterations later included cell death, desquamation and possible active migration of surface cells. The shelf epithelium subjacent to the zone of alteration exhibited increased irregularity in thickness and numerous “invaginations” into the underlying mesenchyme. These alterations are thought to reflect intrinsic changes within the shelf and may play a role in the fusion process. Evidence for surface remodeling following fusion was also observed.
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  • 51
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    The @Anatomical Record 180 (1974), S. 281-283 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Using bipolar fine-wire electrodes, we investigated the function of the pectineus muscle. Electromyography revealed that the main function of pectineus muscle is flexion, adduction and medial (not lateral) rotation of the hip joint. These functions suggest that the spasm of this muscle may be important in the cause of deformities in cerebral palsy.
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  • 52
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Mouse blastocysts were grown in vitro and the ultrastructure of resulting egg cylinders was compared with the ultrastructure of egg cylinders isolated from uterus. Egg cylinders grown in vitro had two or three germ layers and were attached to the bottom of the dish through the layer of trophoblastic cells. The entoderm was composed of two cell types intermixed haphazardly: (1) One type had numerous microvilli on the free surface and a large number of dense bodies, autophagic vacuoles, big and small vacuoles and myelin figures in the cytoplasm. (2) The other type had rich, rough endoplasmic reticulum with wide cisternae. The cisternae were filled with fine, granular material similar to that found as a thick membrane separating the entodermal layer from the rest of the embryo. The first type of cell was ultrastructurally similar to cells of the visceral entoderm of egg cylinders isolated from uterus and the second type was similar to cells of the parietal entoderm. The thick basement membrane observed in embryos grown in vitro was similar to Reichert's membrane. Parietal entoderm and Reichert's membrane were never found as separate structures in embryos grown in vitro. It is probable that the entodermal cells in blastocysts differentiate in vitro into both parietal and visceral entodermal cells within the same layer. Mesodermal and ectodermal cells of vitral embryos were similar to such cells in the egg cylinders isolated from the uterus. The cytoplasm was filled with free ribosomes in the form of polysomes and also contained a few profiles of endoplasmic reticulum, well developed mitochondria and Golgi apparatus. Intercellular spaces between mesodermal cells were large and the cells were not attached to one another. Ectodermal cells were tightly packed and inter-connected with numerous desmosomes. The ultrastructure of egg cylinders in vitro and in vivo was similar. Observed differences might be caused by culture conditions and some of them probably represented the changing pattern of differentiation in vitro.
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  • 53
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 309-329 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Electron microscopic studies were made of hepatocytes from sham-operated rats, adrenalectomized animals fasted 15 hours, and adrenalectomized rats fasted 15 hours but given a single I.P. injection (10 mg) of cortisone acetate. The objective of this work was to define the earliest morphological response of hepatocytes to injection of a glucocorticoid and to provide additional information on the mechanism of hormone action at the cellular level. Hepatocytes from fasted, adrenalectomized rats contained no glycogen particles and very little smooth endoplasmic reticulum (SER). In addition the rough endoplasmic reticulum was disorganized and showed fewer ribosomes and polysomes than found in liver cells from sham-operated rats. Two hours after glucocorticoid injection glycogen particles were seen in numerous centrilobular cells and some periportal hepatocytes. Elements of SER were associated with the glycogen particles. By 4 hours after hormone injection abundant glycogen was found in all hepatocytes. Centrilobular cells showed dispersed glycogen with extensive tubules of SER associated with the glycogen particles. Periportal hepatocytes accumulated glycogen as dense masses scattered throughout the cytosome. SER occurred mainly at the edges of the glycogen masses. Midlobular cells showed glycogen patterns intermediate between periportal and centrilobular cells; masses of dispersed glycogen with abundant SER occurred within and around the glycogen areas of the cells. Glucocorticoid stimulation also caused cisternae of RER to align in parallel arrays, and more ribosomes and polysomes appeared on membranes of RER than in similar cells from adrenalectomized rats. The interpretation is offered that the glucocorticoid-stimulated proliferation of SER is the morphological expression of induced microsomal enzyme synthesis (glucose-6-phosphatase) known to occur under these hormonal conditions.
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  • 54
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The follicular cells of thyroid glands of intact rats respond to TSH challenge by an intense mitotic stimulation and a higher functional activity as measured by the epithelium height. In hypophysectomized rats the same intense response was observed when the thyroid was challenged immediately after hypophysectomy. However, one week later the mitotic response was almost completely absent and the functional response much weaker. This indicates that, although TSH is the main regulating factor of the functional activity and cell proliferation of the thyroid follicle, its effect is conditioned by additional factors. These factors may originate both from the anterior and/or posterior pituitary, since a significantly higher response was obtained by injecting anterior or posterior pituitary powder during the interval between hypophysectomy and TSH challenge. Prolactin, vasopressin and oxytocin also boosted the mitotic response to TSH. Posterior pituitary powder alone (without TSH challenge) was not mitogenic for the thyroid gland either in intact or hypophysectomized rats, while it was mitogenic for the adrenal glomerulosa. The low thyroid mitotic responsiveness does not reflect a general unspecific effect on mitoses of all cells, since the esophageal epithelium was not similarly affected by hypophysectomy or by replacement therapy.
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  • 55
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Adrenal glands of the domestic duck (Anas platyrhynchos) were fixed in formaldehyde-glutaraldehyde for light and electron microscopical examination. Each gland is encapsulated by a layer of connective tissue and consists of two major secretory cell types, the interrenal cells and the medullary cells. In section, the medullary cells appear as islands of tissue dispersed throughout the gland. The interrenal cells are characterized by numerous lipid droplets and abundant mitochondria having mainly tubular cristae. They have an extensive Golgi apparatus, moderate amounts of smooth endoplasmic reticulum and a lesser amount of rough endoplasmic reticulum. Lipid droplets and mitochondria in interrenal cells were seen frequently in association with the endoplasmic reticulum. Adjacent interrenal cells had numerous regions of pentalaminar fusion and intermediate junctions.Medullary cells were characterized by a large population of electron opaque neurosecretory granules. These cells contained fewer mitochondria and cisternae of endoplasmic reticulum than the interrenal cells. In many cases the medullary cells and interrenal cells were closely juxtaposed and were separated by a thin band of extracellular matrix.
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  • 56
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Light microscopy of semithin sections revealed an increase in blood vessel profiles between one and three weeks postnatal. Ultrastructurally, at birth, there were few patent vessels, but endothelial cells enclosing a slit-like lumen were numerous. The endothelial cells contained a high concentration of free ribosomes and pinocytotic vesicles. Pseudopod projections of the endothelial cells into the vascular lumen were often present. The nuclei were very irregular and dense with clumped chromatin. The basal lamina varied in thickness. During the period between one and three weeks the nuclei of endothelial cells became less dense; the lumen became patent and the endothelial wall progressively thinner. The periphery of the vessel became completely surrounded by glial end feet and the basal lamina was regular and prominent. By three weeks, most blood vessels resembled blood vessels observed in a mature animal. Pericytes were present at all stages of development. The extracellular space which was quite conspicuous at birth was greatly reduced by the third week.
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  • 57
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A radioimmunoassay for insulin, together with ultrastructural observations of the endocrine pancreas, were utilized to investigate developmental aspects of insulin storage and secretion in the chick embryo. Immunoreactive insulin was detected from the fifth embryonic day onwards, in both the pancreas and blood plasma. In addition, margination of well-developed beta granules, and emiocytotic events were observed as early as the fifth embryonic day. The initial appearance of insulin, together with its subsequent developmental profile, correlate well with major metabolic events occurring in the embryonic chick, and are discussed in relation to a functionally responding system, the developing liver. The present data show that the chick endocrine pancreas has the potential for activity very early in development, and that insulin may be secreted at earlier embryonic stages than hitherto accepted.
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  • 58
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The fine structure of the group IA sensory nerve endings from normal human muscle spindles was studied in transverse and longitudinal sections. Two arrangements of microfilaments, approximately 75 Å in diameter, were found in each of ten spindles examined. The first was a central aggregate of densely packed filaments. The aggregates were partly surrounded by mitochondria, and were oriented parallel to the longitudinal axis of the sensory ending as it encircled the intrafusal muscle fiber. Individual aggregate filaments of glycerinated endings appeared to react with heavy meromyosin. The second arrangement was a filamentous network in the periphery of the sensory ending profiles. These microfilaments approached and appeared to merge with the surface membrane. They resembled the microfilaments that others have described in growth cones of cultured neurons. Both types of microfilaments are thought to be involved in changing the shape of the sensory endings during stretch and relaxation of the spindle.
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  • 59
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The behavior of somatic cell chromatoid bodies in the planarian Dugesia dorotocephala during mitosis has been studied by electron microscopy. The relatively undifferentiated beta (progenitor) cells are the only somatic cells containing chromatoid bodies and also are the only dividing somatic cells. Somatic cell chromatoid bodies are known to disappear as differentiation takes place and reappear when dedifferentiation occurs. Interphase and prophase beta cells have juxtanuclear and peripheral cytoplasmic chromatoid bodies. There is no ultrastructural evidence to suggest they are derived from formed nuclear material. During metaphase and anaphase, the chromatoid bodies are segregated from the chromosomes and adjacent cytoplasm by cups of double membranes. By the completion of telophase, the chromatoid body size and number immediately adjacent to the nucleus is markedly decreased and extremely large chromatoid bodies may be found further out in the cytoplasm. These findings are compared to the behavior of germ cell chromatoid bodies and discussed in terms of their possible significance and function.
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  • 60
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 61
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    The @Anatomical Record 180 (1974), S. 565-579 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Seminiferous tubules from mouse testes were studied with the light microscope after the efferent ductules had been ligated for 48 hours. As a consequence of ligation, the tubules became markedly distended by the fluid which they accumulated; the epithelium was reduced in height, and exhibited a significantly less complex stratification than in the normal. Longitudinal sections of the distended tubules, particularly those in the early stages of the seminiferous cycle, revealed pillar-like epithelial profiles arranged in a repetitive series. Each “pillar” consisted of Sertoli cell cytoplasm along with two generations of spermatids, the older generation embedded within the Sertoli cell, and the younger generation aligned, one cell above the other, along its sides. Oblique or grazing sections through tubules exhibiting the same stages of spermiogenesis revealed band-like epithelial profiles arranged in parallel array. The two types of epithelial configurations are interpreted as representing a series of circumferentially oriented ridges within the tubule. It is postulated that each spermatid generation within a ridge constitutes a single clone, and that it is the cytoplasmic bridges joining the spermatids, in combination with their attachment to the Sertoli cells, which provide the organization, delineation, and structural stability of the ridges.
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  • 62
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    The @Anatomical Record 179 (1974), S. 147-161 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The organization of the sensory innervation of Golgi tendon organs (GTO) from E. carpi ulnaris of the cat is described. The large Ib afferent fiber gives rise to small myelinated branches which become oriented longitudinally in a neural compartment of the GTO capsule lumen. The latter give rise to smaller, unmyelinated branches which further arborize among loosely packed collagen bundles. The unmyelinated fibers form numerous varicosities and small terminal branches which have portions of the axolemma covered only by basal lamina which intervenes between the collagen bundles and the axolemma. In places, the axon's surface may lack all investments and nerve and collagen come into intimate association. The large unmyelinated branches and their varicosities have different axoplasmic characteristics compared with the small unmyelinated terminal portions. The latter contain few or no mitochondria, vesicles, neurotubules, and neurofilaments. In addition to the description of the terminals, the similarities and differences of the innervation of the GTO, compared with other mechanoreceptors, are discussed.
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  • 63
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The vaginal epithelium of the normal estrous mouse shows narrow intercellular spaces, many cytoplasmic fibrils and a continuous basal lamina. At 100 days of age, the vaginal epithelium of mice which had received 5 or 20 μg estradiol-17β, 20 μg ovine prolactin, or 5 μg estradiol-17β + 20 μg prolactin within the first few days of postnatal life, shows wider intercellular spaces in the middle epithelial layers than occur in normal estrous mice. In addition, the mice receiving 20 μg estradiol-17β show prominent intercellular spaces in the basal cell layer and interruptions in the basal lamina, which permit penetration of cytoplasmic processes into the subjacent connective tissue. The relevance of these findings to vaginal carcinogenesis is considered.
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  • 64
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    The @Anatomical Record 179 (1974), S. 253-271 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Ultrastructural changes of rat blastocysts during delayed implantation were studied 16, 20, 24 or 30 hours after estrogen was given to induce implantation.In the inner cell mass the presence of long cytoplasmic processes penetrating deeply into the neighboring inner cell mass cells is seen at 16 hours. Most cells also show an increased number of ribosomes, polyribosomes and granular endoplasmic reticulum.The trophoblast is featured by the formation of large amounts of glycogen and many inclusion bodies. Glycogen granules appear first in some abembryonic trophoblast cells at 16 hours, and spread to the embryonic pole at 24 hours. New inclusion bodies appear sequentially: multivesicular bodies at 20 hours, multigranular bodies at 24 hours and lamellar bodies at 30 hours. The functions of these inclusion bodies remain to be studied.
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  • 65
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    The @Anatomical Record 179 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 66
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 303-309 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Between the 16th to the 20th day of gestation, the mucosa of the colon of fetal rats changes from a simple tube with a tiny lumen lined by stratified epithelium to a much more complex structure with a large lumen and well-developed crypts lined by a single layer of columnar epithelium. Autoradiographic studies with 3H-thymidine show that cell proliferation is present throughout the stratified epithelium but becomes confined to the lower half of colonic crypts immediately on their formation. The number of epithelial cells shown to be proliferating after exposure to a single pulse of 3H-thymidine is high during this period of organogenesis but decreases rapidly after the 20th day of gestation once the adult mucosal pattern has formed.
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  • 67
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    The @Anatomical Record 179 (1974), S. 297-301 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Study of the developing chick retina with the electron microscope revealed that dyad ribbon synapses begin to form in the inner plexiform layer before synaptic ribbons begin to appear in photoreceptor terminals of the outer plexiform layer. This centrifugal (inner to outer) sequence of synaptogenesis in the predominantly cone retina of the chick differs from the centripetal sequence that has been reported for the predominantly rod retinas of the mouse and rat. This difference does not favor the hypothesis, suggested by others, that the photo-receptor may influence the maturation of inner retinal elements. The different patterns of synaptogenesis are discussed briefly with reference to anatomical differences between the retinas of different species.
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  • 68
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A study of the uptake of exogenous proteins, peroxidase, ferritin, and myoglobin by rabbit blastomeres of different developmental stages was undertaken to determine some of the means by which these stages ingest protein. Exposure of embryos in preimplantation stages, ranging from fertilized ovum to late blastocyst, was carried out in vitro with selected in vivo controls. Blastomeres of early cleavage stages up to the morula show little uptake of peroxidase. However, the endocytosis of peroxidase greatly increases with the morula stages and continues at an elevated level through the blastocyst stages. The uptake of the tracer is initially accomplished via micropinocytotic vesicles and tubules and can have several subsequent fates. The tracer can pass into larger vacuoles and be transported into the cavity of the blastocyst, or can pass into multivesicular bodies where it is presumably degraded by the lysosomal system for cellular use. The use of myoglobin at selected blastocyst stages yielded results similar to those obtained with peroxidase. However, the response by the blastomeres to ferritin is different. Endocytosis of ferritin is scant at all preimplantation stages, even though the ferritin has no difficulty reaching the surface of the blastomeres. The experiment with mechanically denuded blastocysts indicated that ferritin did not adsorb to the cell surface.
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  • 69
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Fertile hens eggs were incubated 48 hours. Embryos were removed from the shell and the cervical region from each excised and placed in a balanced salt solution containing 1% trypsin for 40 minutes. Notochords were isolated by microdissection and further incubated in vitro 48 or 72 hours. Following trypsinization, unincubated notochords were rod-shaped and were shown by electron microscopy to be devoid of extracellular materials or contaminating mesenchymal cells. Extracellular materials, ultrastructurally indistinguishable from those in the perinotochordal connective tissue space in vivo, are present on the surfaces of cell clusters at 48 hours of in vitro incubation. Areas of fibrillogenesis, in which microfibrils are separated from the surface of cells by intermittent basement lamina, are common. At 72 hours of in vitro incubation fibrogenic activity is less evident, but occasionally intense concentrations of small and large microfibrils, basement lamina and other extracellular substances are seen adjacent to notochordal cell surfaces. These observations are of special interest in light of the known role of the notochord in embryonic induction and recent demonstrations that surface-associated substances (specifically collagen) are necessary for normal cytodifferentiation.
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  • 70
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    The @Anatomical Record 179 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 71
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The reproductive biology of Carollia was investigated histologically in 113 females sacrificed at timed intervals after mating in a laboratory colony. A high incidence (44%) of non-pregnant animals could be partially attributed to occasional mating activity at times other than close to ovulation. Breeding success also improved as the males and females were housed together for increasing periods of time. At least 25% of the bats had adrenal cortical-like tissue in the vicinity of the ovaries.Ovulation of the single ovum usually occurred within 48 hours of the onset of female receptivity to the male. Both ovaries were functional, but there was a tendency towards the alternation of successive ovulations. The blastocyst stage was reached and the zona pellucida was lost in the oviduct between days 10 and 12 post-coitum. Blastocysts entered the uterus between days 13 and 16. The slow tubal journey of the ovum is presumably related to the occurrence of mensturation close to the time of ovulation and to the fact that most uterine growth is deferred until after ovulation. Additional ovulations and a new conception were observed during the course of several preexisting pregnancies.Differential stimulation of the two oviducts was evident both prior to and after ovulation. The oviductal secretory cells became engorged during the tubal journey of the ovum with a substance that was Alcian blue 8GX- and Giemsa (pH 4.5)-negative. Occasionally this material could be stained by the PAS procedure.
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  • 72
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    The @Anatomical Record 179 (1974), S. 411-422 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The hearts of 38 black-footed ferrets (Mustela nigripes) were studied with the use of physiologic, microdissection, vascular injection and histologic methods. These animals had a mean heart rate of 265 per minute, a heart weight of 3.7-5.2 gm, and a mean aortic pressure of 139.5 mm Hg. The predominant left coronary artery supplied usually both the SA and AV nodes, as well as the AV bundle, bundle branches and most of the ventricular myocardium. The cells of a well differentiated cardiac conduction system increase in cytoplasmic diameter from the SA node to the distal bundle branches. A cartilaginous right fibrous trigone and thick anulus fibrosus form useful landmarks for delineating AV node and AV bundle relationships. Small size, discrete nodal masses and a unique coronary arterial pattern make this heart an ideal model for histochemical, ultrastructural, electrophysiologic and pathologic circulation research.
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  • 73
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    The @Anatomical Record 180 (1974), S. 137-137 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 74
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 75
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Each of the bilateral nasal glands of Dipsosaurus is surrounded by a thin cartilagenous capsule. A short excretory duct leads to the vestibule of the nasal cavity. This duct connects with the branched principal secretory tubules that end in small terminal segments. Tall columnar cells line the principal secretory tubules, but mucous and tuft cells form the terminal elements. In salt-stressed animals the spaces between dark and light principal secretory cells are dilated. Potassium-dependent, ouabain sensitive, adenosine triphosphatase (Ernst, '72a) was localized within the lateral plications of the principal secretory cells and in the apical microvilli of the tuft cells. These observations are consistent with current concepts of ion transport in salt-secreting epithelia, and they suggest that the tuft cells, not found in avian salt glands, play a role in the unusual physiology (Templeton, '66) of the nasal glands in this reptile.
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  • 76
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    The @Anatomical Record 179 (1974), S. 507-516 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In 2 dogs, 5 cats and 30 human cadavers the diaphragmatic innervation has been studied macroscopically and microscopically. General findings of previous authors regarding phrenic and intercostal nerve contributions have been confirmed and subdiaphragmatic connections from the coeliac plexus to the diaphragm have been clearly demonstrated. The presence of this viscerosomatic interconnection in half of the human subjects studied, highlights the possible importance of autonomic control of diaphragmatic musculature. The finding of comparable autonomic connections in dogs raises the possibility of pursuing the question experimentally by carrying out nerve degeneration studies. In addition the matter of surgical incisions in the diaphragm has been reconsidered and the suggested placements have been illustrated.
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  • 77
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    The @Anatomical Record 180 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 78
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    The @Anatomical Record 179 (1974), S. 543-546 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Connective tissue remodelling has been studied at the fine structural level at the periphery of skin wounds repairing by both first and second intention. The periphery of such wounds was studied as it was predicted that not only would remodelling between old and new connective tissue be taking place, but that the fibroblast would be involved. Excisional and incisional wounds were made in the skin of adult mice and biopsied 14 days later. Our results showed that numerous fibroblasts in the junctional zone between old and new connective tissue exhibited intracellular collagen within vesicles. These findings indicate that the fibroblast is capable of phagocytosing and degrading collagen and has a fundamental role to play in connective tissue remodelling.
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  • 79
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    The @Anatomical Record 180 (1974), S. 3-13 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Muscles of the perineal region were dissected in 20 cats. Levator ani muscle was composed of two parts: iliocaudalis and puboischiocaudalis; both parts inserted entirely on caudal vertebrae, as did the coccygeus muscle. A well developed band of smooth muscle, the pars analis of retractor penis (clitoridis), inserted on the anal canal to retract the anus. The external anal sphincter had pars caudalis and pars cranialis divisions, the latter covered paired anal sacs. In addition, a distinct sphincter encircled each anal sac duct. In the male, levator scroti muscle originated from external anal sphincter. There was no continuity between external anal sphincter and bulbospongiosus muscles. Cremaster muscles were absent in the cat. In the female, pars cranialis of external anal sphincter gave origin to the constrictor vestibuli muscle, and pars caudalis to constrictor vulvae muscle. Bulboglandularis muscles were present in both sexes. Urethralis, ischiourethralis, and ischiocavernosus muscles in the cat were similar to other quadripeds.
    Additional Material: 6 Ill.
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  • 80
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A glycoprotein coat is demonstrable on the free surface of both the blastocyst and uterine luminal epithelium of the mouse on day 4 and day 5 of normal pregnancy, and on day 7 of delayed implantation, using concanavalin A-peroxidase and ruthenium red. The coats are apparently negatively charged, as shown by their binding with colloidal thorium dioxide. The cell coat on uterine epithelium is appreciably thicker than that on the blastocyst. The information currently available is sufficient to suggest that simplistic mechanisms such as change in charge or total thickness cannot be the sole basis of initial adhesion, but that some localized reduction of the uterine surface coat accompanies adhesion. However, considerably more information is necessary concerning the nature of the surface coats before a more comprehensive understanding of the role of adhesion in implantation can be achieved.
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  • 81
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: It has long been known that in certain mammalian species the masseter muscle is a fast-twitch muscle in spite of its red colour. We have investigated the histochemical fiber composition of this muscle in the rabbit and in different species of rodents. In the mouse, rat and guinea pig the masseter is uniformly composed of fibers displaying alkali-stable and acid-labile myosin ATPase activity like most fibers in fast-twitch hindleg muscles and moderate to high succinate dehydrogenase activity. The homogeneity of the histochemical profile with respect to myosin ATPase activity makes this muscle especially suitable for correlated physiological, biochemical and ultrastructural studies. The rabbit masseter has a basically similar though relatively heterogeneous fiber composition with atypical histochemical properties. A sizable population of fibers in this muscle exhibit high levels of both alkali-stable and acid-stable myosin ATPase activity. Mitochondrial α-glycerophosphate dehydrogenase activity, which reflects the glycolytic capacity of skeletal muscle fibers, varies in the masseter of different species in a way which cannot be exactly predicted on the basis of the reactions for myosin ATPase and succinate dehydrogenase.
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  • 82
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Combined morphometric and autoradiographic methods were used to analyze the postnatal growth of rat lung from 1-21 days after birth. Each cell population had distinct growth patterns with an increase in the number of fibroblasts and capillary endothelial cells largely determining the increase in interstitial volume and capillary surface, respectively. The height of proliferation activity in mesodermally-derived cells was concurrent with the outgrowth of secondary alveolar septa (between days 4 and 13). Analysis of the location of labeled cells on day 7 showed that the higher labeling index on septal crests could be ascribed to the proliferative activity of fibroblasts and endothelial cells.Within the alveolar epithelium only the type II alveolar cells had a detectable labeling index. Over the first week, the number of type I epithelial cells steadily increased while the number of type II cells remained constant. Subsequently the number of type II cells increased rapidly, reached a peak on day 13 and then decreased, whereas type I cells continued to increase in number. These facts led us to consider that type II epithelial cells may represent the stem cell population of alveolar epithelium. The height of proliferative activity of type II cells on day 7 coincided with the outgrowth of septal crests and was followed by the steepest increase in number of type I and II cells.Between the 10th and 21st day labeling indices rapidly declined, cell production became undetectable after day 13. Increase in alveolar and capillary surface area however continued, resulting in a thinning of the interstitial layer and of the epithelial and endothelial sheets.
    Additional Material: 8 Ill.
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  • 83
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 629-643 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Explants of six-day chick embryo skin, cultivated in a chemically defined medium (Waymouth Medium MB 752/1) for one to eight days were fixed and processed for electron microscopic study. Excellent development and differentiation of chick embryo skin was recorded. The skin cultivated in vitro matured much earlier than in ovo. After one day in vitro the morphology of the skin is similar in the stage of development to that of a 10-12 day embryo skin in ovo. After two or four days in culture, the skins are comparable to those of 12-14 day or 15-16 day in ovo embryos, respectively. The periderm of the epidermis was highly developed and contained a large number of peridermal granules after six days of culture. The skin proper, contained a granular layer, which resembled the skin of a 17-day embryo. Complete cornification of the epidermis was observed for the first time in vitro after 8 days of incubation. Keratohyalin granules which were claimed to be absent in avian skin, were observed.
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  • 84
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The localization of alkaline phosphatase activity in the ultimobranchial bodies was studied at the fine structural level in Holtzman rat embryos from the 15th to the 19th day of gestation, and also in four-week old rats of the same strain. In the embryos, no alkaline phosphatase activity was found before the 17th day of gestation. From that day on, plasma membranes of glycogen-rich cells show the reaction product regardless of their location in the wall of the ultimobranchial bodies. However, when the same cells are seen on cell cords of the median thyroid, they are negative. In the four-week old rats, plasma membranes of ultimobranchial cells are strongly reactive. C cells are negative both before and after birth. Small thyroid follicular lumina with positive apical cell membranes are also noted in four-week old rats. These positive thyroid follicles are not more differentiated than those previously described in 19-day old rat embryos. It is concluded that new thyroid follicles are formed after birth. These results are discussed in relation to the hypothesis that when ultimobranchial cells are transformed into follicular cells, they undergo the same alkaline phosphatase changes as those observed during the maturation of follicular cells derived from the median thyroid primordium. The cytochemical method used is also criticized.
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  • 85
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 86
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 1-1 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 87
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Phagocytosis of supernumerary spermatozoa contained within the perivitelline space was observed in 7 of 28 two-cell mouse embryos cultured for 45 hours post-insemination (approximately 20-24 hours after cleavage). The spermatozoa were incarcerated as a result of elevations of the blastomere cytoplasm which gradually surrounded the sperm, overlapped and fused, thus forming a typical phagocytic vacuole. Phagocytosis was not observed in two-cell embryos cultured for less than 20-24 hours after cleavage; this indicates that the blastomeres of two-cell mouse embryos in vitro require approximately 24 hours to develop one of the characteristics of somatic cells, i.e., the ability to recognize and phagocytize foreign material.
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  • 88
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 41-48 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This report compares the arterial supply of the lumbo-sacral spinal cord in the monkey with that of man. The arterial supply to the lumbo-sacral cord of 100 monkeys (82 Rhesus and 18 Mangabey) was demonstrated by perfusion techniques. We tabulated the level and side of origin of the great anterior medullary artery. Previous authors have shown that in man the peak incidence of the great anterior medullary artery is at T-10. The peak incidence in the monkey is at L-1. There are other features of the arterial supply to the lumbo-sacral cord of the monkey that are different from man.
    Additional Material: 6 Ill.
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  • 89
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The urinary bladder of the bullfrog, Rana catesbiana has been studied by light and electron microscopy. Three epithelial cell types were found: (1) granular cells, (2) mitochondria-rich cells, and (3) basal cells. The structure of the Rana catesbiana bladder differs from that of the toad Bufo marinus, in several respects: it lacks a mucous (goblet) cell type, its granular cells do not contact the underlying basement membrane, it has specialized, smooth-muscle cell-basal epithelial cell contacts, not previously described in amphibian bladders, and its mucosa is richly innervated. Mitochondria-rich cells within the bullfrog bladder epithelium were occasionally observed touching the basement membrane. The specialized smooth muscle-basal cell contacts provide anatomical evidence for how regulatory vasoactive substances such as neurohypophyseal peptides might alter epithelial geometry. Many nerve endings invest the mucosa just beneath the epithelial basement membrane in proximity to mitochondriarich cells and basal cells. The possible role of neural regulation in epithelial transport was discussed.
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  • 90
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 49-61 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The chloride cells of the lamprey, Lampetra japonica, have been studied by electron microscopy. The most characteristic feature of the chloride cells in lamprey is that the cytoplasm is filled with a large number of mitochondria and numerous agranular cytoplasmic tubules arranged as bundles or as branched reticular networks. These tubules are frequently continuous with the plasma membrane. They are also characterized by a coating on the cisternal surfaces with a dense material which appears ridge-like at high magnification. These ridges are oriented spirally along the cisternal surface of the tubule. They are regularly spaced at an interval of about 160 Å and have a pitch of about 45°. The functional significance of the cisternal coat is unknown. Sometimes, intracisternal tubules are observed to be contained within the lumina of the agranular cytoplasmic tubules. These intracisternal tubules are considered to be formed by an intracisternal deflection of only one leaflet of the unit membrane of the agranular cytoplasmic tubules. Membrane fusion is observed to occur between closely associated agranular cytoplasmic tubules.
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  • 91
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 63-81 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The I segment length has been measured and the number of thin filament periods per I segment has been counted in electron micrographs of Rhesus monkey and human leg muscle fibers. The number of I segment periods in the monkey fiber (60) and in the human fiber (66) multiplied by axial periodicity (385 Å) in thin filaments of living fibers (Huxley and BROWN, '67) plus 1,000 Å allowed for Z line width in living fibers, provided a formula for calculation of I segment lengths in living fibers. The calculated I segment lengths are 2.41 μ for the monkey and 2.64 μ for the human fiber. The ratio of calculated I segment length over an assumed constant thick filament length (1.6 μ) among vertebrates is in close agreement with the ratio of measured I segment length over measured thick filament length in micrographs of frog, rat, monkey and human leg muscle fibers. The calculated I segment length in the frog (1.95 μ) is compared with that of the human (2.64 μ) to show the relation of I segment length to the length-developed tension diagram and to the series elastic components of the skeletal muscle fiber.
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  • 92
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: An initial study of the effects of long-term ovariectomy on fimbrial and ampullar epithelia from rabbit oviducts has been made with the scanning electron microscope. Several of the rabbits were given estradiol benzoate before they were killed. These observations were compared with those of epithelial cells from similar oviductal segments from post-ovulatory rabbits that served as controls.Fimbriae from oviducts of control animals were densely ciliated, partially concealing the bulbous processes of the secretory cells. In the ampullae the processes of the secretory cells were the predominant structure, their bulbous apices rising frequently above the tips of the cilia.When rabbits had been spayed for 16-18 months, the epithelial cells of both fimbriae and ampullae showed a remarkable change. A few cilia in small clumps were scattered among the secretory cells. The free surface of the secretory cells had become flattened and hexagonal in shape. Their microvilli were short, and from the center of each cell a thick, stubby central cilium protruded.Estrogen given the long-term spayed rabbits caused almost complete reciliation as well as restoration of the bulbous processes of the secretory cells.
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  • 93
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 119-125 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The effects of blinding on cellular structure and porphyrin pigment content were studied in Harderian glands of pinealectomized and non-pinealectomized adult female golden hamsters. Uterine weights were used as a criterion for pineal activity. Five weeks post-operatively, no significant changes were observed in the Harderian glands or in the uterine weights of animals in either group. Eleven weeks post-operatively, the blinded hamsters with intact pineal glands had significantly lowered uterine weights and Harderian glands that exhibited diminished amounts of porphyrin pigments and cellular characteristics of the male hamster. Harderian glands and reproductive organs from the 11-week blinded-pinealectomized hamsters did not differ from those of untreated controls.
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  • 94
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Postnatal maturation of nonmyelinated fiber bundles (Schwann bundles) was studied in the sciatic nerves of Snell's dwarf mice. The homozygous recessive of this strain has been previously shown to be characterized by multiple pituitary hormone deficiencies and secondary hypothyroidism.In the normal littermates a reduction occurred between 10 and 14 days in the number of fibers per fascicle, or subdivision, of each Schwann bundle, and by 26 days nearly all of the axons were separately embedded in cytoplasmic furrows of their associated Schwann cells. Only a few large fascicles were seen in normal sciatic nerve specimens at 26 and 50-53 days. In contrast, fiber bundle fascicles in the mutant nerves were still represented, even at 50-53 days, by numerous tightly-packed axons, as seen in the immature nerves at 10-12 days post-partum.On the basis of the dwarf's physiological background, these results suggest an involvement of the endocrine system during later stages of peripheral nerve maturation. The possible mechanisms affected by postnatal endocrine deficiency and thereby leading to delayed segregation of nonmyelinated fibers within Schwann bundles are discussed.
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  • 95
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 96
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The use of potassium pyroantimonate-osmium tetroxide as a combined fixative and cation-capture agent has permitted the observation of finestructural changes in cation distribution in rat parotid acinar cells following administration of isoproterenol (IPR). During the secretory phase of the response, there is a diminution of antimonate-precipitable cation in the cytoplasm combined with an increase along the plasma membrane and on secretory channels. At four hours after IPR, cytoplasmic precipitates return but deposits disappear along the membrane. Membrane deposits return slowly at later times after the stimulus. Decreased antimonate-precipitable cation was observed in nuclear heterochromatin between 4 and 20 hours after IPR. This may be related to the induction of cell replication by the drug. During the DNA synthetic phase of the response to IPR, an unusual patchy osmiophobia was observed in nuclei. Mitotic chromosomes contained heavy antimonate deposits. Some of the early changes in cation distribution observed after isoproterenol administration mimicked changes seen in damaged cells.
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  • 97
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 178 (1974), S. 759-767 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Lactic dehydrogenase activity was studied in hair follicles from both the bald and hairy regions of the scalp of the stump-tailed macaque by the application of the method of Lineweaver-Burk to the histochemistry. There was no difference between terminal and vellus follicles in total lactic dehydrogenase activity. During anagen, the activity was higher in the lower part of the external sheath and was similar to that in the bulbar sac. The activity of the heart-type lactic dehydrogenase (H-LDH) was high in the matrix, whereas that of the muscle-type lactic dehydrogenase (M-LDH) was high in the external sheath of the lower and upper bulb portions. The activity of M-LDH in the matrix of terminal hair follicles was extremely low compared with that in vellus follicles. In telogen, however, there was no difference between the two types of follicles.
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  • 98
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 375-383 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This investigation was designed to obtain more anatomical information about the neuromuscular mechanism of the jaw movement by a comparative study of the insectivores. The muscle spindle distribution in the masticatory muscles of Temminck's mole showed a strong similarity to that of the Japanese shrew-mole. Muscle spindles counted were 174 in number in a restricted area of the jaw-closing muscles, 92 in the horizontal and 39 in the vertical portion of the temporalis muscle, 18 in the medial pterygoid muscle and 25 in the profound portion of the masseter muscle. The lateral pterygoid muscle, and the jaw-openers, contained no spindles.
    Additional Material: 5 Ill.
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  • 99
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 405-410 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The effect of continuous darkness on diurnal variation of glycogen content in pineal cells of adult mice was investigated by means of a semiquantitative histochemical method. In dark-maintained mice, a diurnal rhythm in pineal glycogen content persisted for the first 7 days of darkness. After 14 days or longer of continuous darkness, however, a clear relationship between the glycogen content and time of day became less apparent. Reversed conditions of environmental lighting caused a complete reversal of the glycogen rhythm in the pineal as early as the fifth day. When mice that had been kept in reversed conditions of lighting for 7 days were exposed to continuous darkness, the reversed glycogen rhythm also persisted in darkness of 7 and 14 days, but it was abolished by darkness of 28 days. The nuclear density of pineal cells was significantly lower at 9 am than at 9 pm in controls. In dark-maintained mice, however, no significant diurnal variation in pineal cell size was generally evident except 2 and 3 days after the initiation of darkness.
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  • 100
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 341-350 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Minute amounts of white or brown adipose tissue can be localized in situ within seconds by covering the organ surfaces with an alkaline solution of dithizon (diphenylthiocarbazone) in alcohol and water. The adipose tissues stain deep green, while the other organs remain unstained, or appear in various shades of pink and red. This technique has been successfully applied to various groups of vertebrates (mammals, birds, reptiles, amphibians and fishes), and it works in fresh, in deep frozen and in formalin-fixed specimens. It fails after tissue fixation in mercuric chloride-containing fluids. In vitro studies show that the staining reaction is due to (1) a preferential solubility of small amounts of dithizon in adipose tissue lipids, and (2) the development of a green color, which appears when dithizon dissolves in lipids or organic solvents.
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