Bibliothek

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • 1975-1979  (7)
  • 1970-1974  (12)
  • Life and Medical Sciences  (19)
Datenquelle
Materialart
Erscheinungszeitraum
Jahr
Schlagwörter
  • 1
    Digitale Medien
    Digitale Medien
    The cytology of hofbauer cellsThis study was supported by grant 5 R01 HD-02613 from the National Institute of Child Health and Human Development. (1970)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 167 (1970), S. 231-251 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: Cytological investigation of Hofbauer cells in various stages of gestation reveals that they are similar to normal macrophages except for unusually large cytoplasmic flanges and included vacuoles. The system of vacuoles is apparently the result of macropinocytotic activity. The individual vacuoles undergo asymmetrical collapse in regions adjacent to small juxtavacuolar tubules thought to be derived from the agranular endoplasmic reticulum. In addition, coated micropinocytotic vesicles are common. Hofbauer cells thus appear to be a type of macrophage with an unusual capacity for fluid ingestion. In younger placentas, Hofbauer cells are usually associated with extracellular compartments within the stroma. These compartments are relatively free of collagen fibrils and demonstrable ground substance and are clearly demarcated from the rest of the stroma by processes of fibroblasts. The abundance of these cells in early placentas, their location in the stroma, and evidence of their pinocytotic activity suggest that these cells may play a role in removal of proteins from interstitial fluid. Hofbauer-like cells were also studied in the guinea pig and the little brown bat. Of these two species, the Hofbauer-like cells of the bat more closely resemble human Hofbauer cells in that they show evidence of extensive macropinocytotic activity.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091670211
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Uptake of exogenous protein by the preimplantation rabbitThis investigation was supported by grant 2 RO1 HD04962 from The National Institute of Child Health and Human Development. (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 179 (1974), S. 311-330 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: 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.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091790304
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Mouse uterine glands during the delayed and induced implantation periodsThis study was supported by Grants HD 04962 and HD 10342 from the National Institute of Child Health and Human Development and by National Institute of Health Traineeship Grant GM 021025 to the Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri. (1978)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 190 (1978), S. 271-283 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: Mouse uterine glandular epithelium during the lactationally delayed implantation period and after estradiol induction of implantation was investigated using light and electron microscopy. During the delayed implantation period the lumen of this simple tubular gland is narrowed. The glandular epithelial cells have a well developed Golgi complex lateral to the nucleus, and numerous cisternae of smooth and rough endoplasmic reticula (RER) and many electron lucent apical vesicles of sizes up to 0.2 μm in diameter near the luminal border. The basal region contains lipid droplets and dispersed, irregular cisternae of RER. Twenty-four hours after the administration of 17β-estradiol the glandular lumina become dilated but the luminal content does not stain with azure B. Ultrastructurally the glandular cells are not remarkably different from those seen during the delay period. However, by 48 hours after estradiol administration the glandular lumina are not only dilated but filled with material which stains intensely with azure B and is ultrastructurally dense and homogeneous. The apical region of the glandular cells contains granules up to 0.4 μm in diameter composed of electron dense material similar in density to that seen in the glandular lumen. In addition, the Golgi complex has assumed a position apical to the nucleus, and the basal RER has an increased number and more orderly arrangement of cisternae.The changes seen in the uterine glands after the induction of implantation during the delay period are apparently indicative of increased secretory activity of the glandular epithelia. However, the contribution of the glands to the changes in uterine fluid composition has yet to be established.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091900210
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Surface coats of the mouse blastocyst and uterus during the preimplantation periodSupported by grant 2 R01 HD04962 from the National Institute of Child Health and Human Development. (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 180 (1974), S. 31-45 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: 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.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091800105
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Differentiation and migration of endoderm in the rat and mouse at implantationThis study was supported by grants HD 04962 and HD 10342 from the National Institue of Child Health and Human Development. (1978)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 190 (1978), S. 65-77 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The initial differentiation of endoderm at the time of onset of implantation, and the subsequent rapid differentiation of visceral and parietal endoderm were studied in the rat and mouse. Transmission electron microscopy illustrates the reorientation and loosening of embryonic cell mass cells during implantation, as well as cytological evidence that endoderm cells have differentiated. Using scanning electron microscopy, parietal endoderm consists of individual stellate cells with numerous peripheral branching filopodia. As these cells migrate abembryonically, the rest of the embryonic cell mass becomes recom-pacted. The visceral endoderm proliferates and forms a columnar epithelium which has the cytological characteristic of an absorptive epithelium and is able to ingest exogenous proteins. Thus, by 24 hours after implantation, the two endo-dermal derivatives have assumed widely diverse shapes and different types of associations and rates of replication, and are probably performing different functions.
    Zusätzliches Material: 16 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091900107
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    Protein uptake by rat preimplantation stagesThis study was supported by grant HD 04962 from the National Institute of Child Health and Human Development. (1973)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 175 (1973), S. 539-559 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The protein tracers, horseradish peroxidase and ferritin, are demonstrable in the subzonal space of all preimplantation stages within ten minutes when incubated in vivo or in vitro. However, there is very little uptake of these proteins by ova and two-cell stages. By the blastocyst stage there is greatly increased uptake of exogenous protein. The proteins appear in coated micropinocytotic vesicles and tubules, larger vacuoles, and more complex bodies. Blastocysts from the period of lactationally delayed implantation show an even greater amount of uptake, especially in the supranuclear region. Peroxidase reaction product can be demonstrated in the cavity of day 5 blastocysts in 30 minutes, and in the cavity and basal lamina of the blastocysts during delayed implantation in ten minutes. Ferritin was more sparsely distributed, and was not seen in the blastocyst cavity in any of the time periods. Peroxidase is apparently transported via an intracellular pathway, since it is not seen in the elaborate intercellular spaces between trophoblast cells. Acid phosphatase activity is demonstrable in vacuoles, dense bodies and Golgi cisternae in all stages, indicating that the potential for degradation of ooplasm and phagocytized material by a lysosomal system is present in all of the preimplantation stages examined.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091750304
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    The nonuniform distribution of acidic components on the human placental syncytial trophoblast surface membrane: A cytochemical and analytical studyThis work was supported by National Institute of Health Traineeship GM02016 (D.M.N.), National Institute of Child Health and Human Development grants #5 R01 HD06415 (A.C.E.) and #HED 5 R01 HDO 7562 (C.H.S.), and the National Foundation for March of Dimes grant #CRBS - 309 (C.H.S.). (1976)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 184 (1976), S. 159-181 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The surface coat of syncytial trophoblast from term human placentas was studied using cytochemical methods (colloidal iron, alcian bluelanthanum nitrate, dialyzed iron) in coordination with tissue enzyme digestions (trypsin, neuraminidase) and sialic acid analyses. The presence of at least two highly acidic anionic components that contribute significantly to the surface negativity of trophoblast has been demonstrated. The first of these, sialic acid, was removed with neuraminidase. Tissue digestion with this glycosidase was accompanied by a decrease in trophoblast surface staining with colloidal iron, a decrease in tissue sialic acid, and an increase in the concentration of sialic acid in the incubating medium. Results from methylation experiments were consistent with the presence of sialic acid. The second anionic component(s) was identified by removal with trypsin of a glycocalyx constituent that stained with both colloidal iron and lanthanum. After trypsinization, tissue sialic acid levels were not significantly different from control values, and no detectable sialic acid was present in the incubating medium. The identity of this anionic component has not been established. Both sialic acid and nonsialic acid acidic components are distributed in higher density on membrane of microvilli than on intermicrovillous surface membrane. In addition, the sialic acid moieties appear to be clustered in the glycocalyx.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091840204
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Transport and barrier function in the chorioallantoic placenta of the bat, Myotis lucifugusThis study was supported in part by grants 5 R01 HD-02613 from the National Institutes of Child Health and Human Development (A.C.E.) and GB-6435 from the National Science Foundation (W.A.W.). (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 170 (1971), S. 381-399 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The chorioallantoic placenta of the bat (Myotis lucifugus) is hemodichorial and has an ectoplasmic layer and an intrasyncytial lamina interposed between the maternal blood space and the underlying endoplasmic portion of the syncytial trophoblast. The barrier and/or transport function of the trophoblast of this species was investigated. When Thorotrast was injected into the maternal vascular system, only small amounts appeared in the trophoblast, and it could not be demonstrated deep to the syncytial trophoblast.Injected peroxidase and ferritin were both rapidly taken up by the trophoblast, these tracers being found in coated vesicles and tubules, in multivesicular bodies, and in dense bodies. Peroxidase was transported across the trophoblast and could be found in macrophages in the fetal connective tissue and in vesicles in the fetal endothelium. Since ferritin is present in the cytotrophoblast, macrophages and fetal endothelium in uninjected as well as injected animals, the exogenous material could not be followed beyond the syncytium. In addition to demonstrating the cytological pathway by which absorbed proteins cross the trophoblast of the chorioallantoic placenta of the bat, the results of this study suggest that the labyrinth in this species should be considered a possible route for passage of endogenous proteins to the fetus.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091700402
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Junctional complexes in the preimplantation rabbit embryoSupported by grant HD 09462 from the National Institute of Child Health and Human Development. We would especially like to thank Dr. Karl Pfenninger for extensive assistance in freeze-cleave techniques with the blastocysts. (1975)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 181 (1975), S. 17-33 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The morphology and development of junctional complexes between blastomeres of the preimplantation rabbit embryo were investigated using several approaches. Electron microscopic examination of embryos stained en bloc with uranyl acetate, and the study of junction permeability using horseradish peroxidase and lanthanum nitrate provided information on structure, intermembrane spacing and permeability of the junctional complexes. In addition, the freeze fracture technique was used with day 5 and day 6 blastocysts, since the large size of these embryos facilitated use of this method. These experiments showed that although rudimentary junctions were present between blastomeres of the early cleavage stages, effective tight junctions were not present until the blastocyst stage. Electron microscopic examination of thin sections revealed apical foci of membrane approximation or “fusion” between trophoblast cells by day 4. Freeze fracturing revealed a lattice of interconnecting ridges (on the A face) and grooves (on the B face) in the apical region between trophoblast cells of the day 5 blastocyst. This lattice formed a continuous band along the apical margin of each cell, and therefore constituted a zonula occludens. The zonula occludens of the day 5 blastocyst averaged 2-3 ridges per lattice, while day 6 blastocysts had lattices that averaged 5-6 ridges. Also seen in the freeze fracture replicas from the day 5 and day 6 blastocysts were local accumulations of intramembranous particles on the A face. These particles were often observed in aggregates similar to those of previously described gap junctions. It could not be determined whether these small regions of particles were true gap junctions or a possible primitive form of gap junction because the complementary pitted surfaces (B face pits) were not demonstrated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091810103
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    The implantation chamber, blastocyst and blastocyst imprint of the rat: A scanning electron microscope studyThis study was supported in part by Grant HD-04962 from the National Institute of Child Health and Human Development. Initial acquisition of the scanning electron microscope used was made possible by Health Sciences Advancement Award 5 SO4 RR 06115. (1975)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 182 (1975), S. 137-149 
    Details
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: Splitting the uterus longitudinally through implantation sites makes it possible to obtain access to blastocysts and implantation chambers during stages of implantation of the blastocyst in the rat. On the afternoon of day 5 of pregnancy, blastocysts lie in a shallow antimesometrial depression and tend to fall free of the uterus when the chamber is opened. On day 6, blastocysts are oriented in a mesometrial-antimesometrial plane, occupy a distinct implantation chamber, and tend to adhere to one side or the other of the uterus, leaving an imprint on the contralateral side. After about noon of day 6, some of the blastocysts split in half laterally, and by day 7 all blastocysts which are exposed are split. In addition to demonstrating increased adhesion of blastocyst to uterine epithelium, the procedure clearly shows the progressive elongation of the implantation chamber. The embryonic cell mass is specifically oriented on day 6, and is clasped but not distorted, whereas the abembryonic trophoblast is slightly compressed and indented by the uterine epithelium. The microvilli of the uterine epithelium within the imprint become progressively flattened when compared to the microvilli of the implantation chamber outside of the imprint. The method provides a means of gaining direct access to the surface of uterine epithelium precisely where it has been in association with the blastocyst not only for scanning electron microscopy but also for studies of the properties of the surface constituents.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/ar.1091820202
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...