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991.
The ultrastructural features of the principal cell in the epididymal epithelium of the monkey epididymis are suggestive of
the cell carrying out a dual function of absorption and secretion. Both these functions occur on the luminal surface of the
cell as well as on the lateral and basal aspects of the cell which face the intercellular spaces. Transmision Electron Microscopic
studies of epididymal tissues following their impregnation with lanthanum nitrate indicated that the intercellular spaces
are effectively sealed-off from the luminal space by the apically situated tight junctions between adjoining principal cells.
The intercellular spaces are contiguous with the perivascular spaces of the subepithelial blood capillaries. It is suggested
that the absorptive and secretory functions occuring on the apical surface of cells may be related to the creation of an appropriate
intraluminal milieu for the maturation of spermatozoa while the occurrence of these functions in the intercellular spaces
may represent an exchange of substances between the principal cells and the subepithelial capillaries. 相似文献
992.
B A Lapin 《Journal of medical primatology》1982,11(6):327-341
A short historical review of the use of primates in cancer research is presented followed by a review of various forms of neoplasma observed in the oldest existing Primate Center. Special attention is paid to baboon lymphomas studied for the past two decades at the U.S.S.R. Primate Center at Sukhumi. 相似文献
993.
Alloantigens of squirrel monkey (Saimiri sciureus) IgG were studied using alloantisera prepared by cross-immunizations among four subspecies. The results demonstrated the occurrence of IgG antigenic polymorphism. Three distinct Fd fragment allotypes were detected. Greater alloantigenic complexity occurred among Colombian and Peruvian squirrel monkeys, which occupy the more central regions of the geographic range; Bolivian and Guyanan monkeys, which occupy the extremes of the range, expressed less alloantigenic complexity. 相似文献
994.
Simian cytomegalovirus infections were studied in captive, naturally infected primates and in experimentally infected rhesus monkeys. Neutralizing antibody to simian cytomegalovirus was prevalent in selected species of Old World Monkeys. Naturally infected, rhesus monkeys shed virus in their urine during the entire two-year period of study. Similarly, experimentally infected rhesus monkeys showed neutralizing antibody and viruria for more than two years. The indirect fluorescent antibody procedure was found more sensitive than the neutralization antibody technique but appeared less specific for antibody to cytomegalovirus strains. 相似文献
995.
996.
Effects of intracervical administration of PGE2-gel were studied in pregnant Japanese monkeys (Macaca fuscata fuscata) near term. Administration of PGE2-gel induced cervical ripening and an increase in maternal plasma PGE2 but no change in PGF2α. Ultrastructural observations of the connective tissue of the cervix after PGE2-gel treatment revealed a decrease in the number of collagenous fibers. These results show that intracervical administration of PGE2-gel induces cervical ripening without induction of labor in the Japanese monkey. 相似文献
997.
To investigate the evolution of the Rh blood-group system in anthropoid apes, New and Old World monkeys, and nonprimate animals, serologic typing of erythrocytes from these species with antibodies specific for the human Rh blood-group antigens was performed. In addition, genomic DNA from these animals was analyzed on Southern blots with a human Rh-specific cDNA.Consistent with earlier reports, serologic results showed that gorilla and chimpanzee erythrocytes had epitopes recognized by human Rh D and c antisera, and gibbon erythrocytes were recognized by the c antisera. Surprisingly, some Old and New World monkeys also expressed a Rh c epitope on their erythrocytes. No erythrocytes from the nonprimate animals reacted specifically with any of the human Rh antisera.Southern blot analysis with a human Rh-specific cDNA probe detected Rh-related sequences in anthropoid apes, all New and Old World monkeys, and in most nonprimate animals tested. Although some Rh-related restriction fragments were conserved across species lines in primates, the Rh locus was more polymorphic in chimpanzees and gorillas than in humans. In addition, restriction fragments segregating with the presence of the D antigen in humans were present in the primate species that expressed the D antigen. 相似文献
998.
Christopher L. Coe Joseph W. Kemnitz Mary L. Schneider 《Journal of medical primatology》1993,22(5):294-300
Maternal and fetal/infant antibody levels were assessed across pregnancy and at birth to evaluate the prenatal transmission of IgG in the rhesus monkey. Although some antibody was evident in the fetus by midpregnancy, the marked increase in IgG occurred primarily during the last two weeks of pregnancy. This delay until the end of pregnancy would result in low antibody titers in premature infants. In contrast, when gestation length was normal, the placental transfer of IgG was resistant to both dexamethasone treatment and a prolonged period of stress during pregnancy. This resiliency occurred despite an effect of prenatal stress on other aspects of infant development, including physical growth and the fetal synthesis of complement proteins. 相似文献
999.
Carmine Di Ilio Stefania Angelucci Alfonso Pennelli Tonino Bucciarelli Raffaele Petruzzelli Gian Mario Tiboni Sonia Melino Paolo Sacchetta 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,114(4):377-382
Three forms of glutathione transferase (GST) with an apparent isoelectric point of pH 4.65 (GST I), 4.75 (GST II) and 4.9 (GST III) were resolved from the monkey (Macaca fascicularis) placenta after GSH-affinity chromatography followed by chromatofocusing. Substrate specificity, immunological reactivity, as well as N-terminal aminoacid sequences indicate that the three enzymes belongs to the pi class of GST. Reverse phase HPLC analysis indicates that the three GST arise from the combination of two different subunits eluting respectively at 29.60 ± 0.10min and32.43 ± 0.13min. GST I is an homodimer of the 29.60 ± 0.10min subunit, GST III is an homodimer of the 32.43 ± 0.13 min subunit, whereas the GST II is an heterodimer of the 29.60 ± 0.10min and 32.43 ± 0.13min subunits. Our results strongly suggest that unlike human, multiple forms of pi class GST exist in monkey placenta. 相似文献
1000.
Joslc Dias Richard J. Montali John D. Strandberg Linda K. Johnson Michael J. Wolff 《Journal of medical primatology》1996,25(1):34-41
Abstract: Of 1,106 New World primates necropsied from the National Zoological Park (Washington, D.C.) and the Department of Comparative Pathology, Johns Hopkins University School of Medicine (Baltimore, Maryland) 22 (1.9%) animals were identified with 27 neoplasms. Of this group, nine animals (two females, seven males) had a total of 13 endocrine neoplasms. All animals were adults, with an age range of 2.7–25 years (average, 12.1 years). Seven were Callitrichidae and two were Cebidae. The adrenal gland was the most affected organ, with seven (53.8%) neoplasms, followed by the pituitary and thyroid gland with two (15.4%) cases each, and the pancreas and parathyroid gland with one tumor (7.7%) each. All neoplastic disorders were benign. Immunocytochemistry assays for growth hormone, adrenocorticotropic hormone, prolactin, follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, and chromogranin A were performed on two pituitary neoplasms. Pheochromocytoma was the most frequent neoplasm, representing 5 (38.4%) of the 13 neoplasms. The remaining were thyroid cystadenoma (two, 15.4%), corticotrophic cell pituitary adenoma (two, 15.4%), adrenal ganglioneuroma (one, 7.7%), adrenal cortical adenoma (one, 7.7%), parathyroid chief-cell adenoma (one, 7.7%), and pancreatic islet-cell adenoma (one, 7.7%). 相似文献