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1.
Over the past decade, studies on reproductive morphology in the Squamata (snakes and lizards) have expanded tremendously. With the accumulation of these studies and revisions of the terminology based on structural similarities and differences, it is imperative to review the work on tuataras to determine whether the structural organization fits the revised terminology of vertebrates. We investigated the morphology of the male reproductive system in the Tuatara, Sphenodon punctatus (Rhynchocephalia), the sister taxon to the Squamata. Previous studies on the Tuatara used a nomenclature for the testicular ducts different from the current terminology for amniotes. The reproductive system in the Tuatara is consistent with reports in the Squamata. Two rete testis tubules exit the testis within a connective tissue sheath similar to that shown in other squamate species and the protherian Echidna. Each rete testis divides into multiple ductuli efferentes that fuse with the epididymis. The epididymis transitions into the ductus deferens where the sperm become more concentrated into spherical bundles. The ductus deferens enters the cloacal urodeum separately from the ureter. An ampulla ureter or ampulla urogenital papilla was not observed, which differs from previous studies of lepidosaurians. Furthermore, a sexual segment of the kidney (SSK) was not observed, consistent with previous studies on the Tuatara. 相似文献
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D B Budzko D L Madden W T London J L Sever 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1985,179(2):227-231
Levels of lymphocyte responsiveness to T- and B-cell-specific mitogens and expressions of Ia, T4, T8, and T11 surface markers were monitored during the course of Simian acquired immunodeficiency syndrome (SAIDS) in four Rhesus macaques that either died or became ill and survived. The monkey that died showed progressively suppressed responses to concanavalin A (Con A), phytohemagglutinin (PHA), pokeweed mitogen (PWM), and Staphylococcus aureus Cowan I strain (SAC) through the time of death (5 1/2 weeks). For the three animals that survived, the responses of peripheral blood mononuclear cell (PBMC) to the same mitogens were decreased significantly during the period 4-6 weeks after inoculation. Levels of Ia-bearing cells in the PBMC population were markedly reduced in the moribund monkey but were not significantly decreased in the three survivors. There was no significant change in the percentage of T11-bearing cells in any of the study animals. The ratio of T4- and T8-positive cells did not vary significantly during the 18 weeks of observation in any of the animals. The infected animals showed other evidence of immunosuppression including neutropenia, lymphopenia, and depletion of lymphocytes in lymph nodes. The animal that had progressive disease and death also had Kaposi-like lesions and staphylococcal septicemia. These results indicated that in vitro evidence of immunosuppression due to SAIDS appears within a few weeks after infection and this may progress in animals that die. 相似文献
3.
An Improved Diluent for Rubella Hemagglutination and Hemagglutination-Inhibition Tests 总被引:3,自引:2,他引:1 下载免费PDF全文
Angela E. Auletta Gary L. Gitnick Carrie E. Whitmire John L. Sever 《Applied microbiology》1968,16(5):691-694
Rubella hemagglutinating (HA) antigen was prepared in BHK-21 tissue as 5% cell suspensions and from unconcentrated and 20× concentrated infected supernatant fluids. In some instances, unconcentrated fluids were treated with Tween 80 and ether; cell suspensions were treated with ether alone. Preparations were tested for HA activity in dextrose-gelatin-Veronal (DGV) buffer solutions; 0.85% NaCl; Sorenson's phosphate-buffered saline, pH 7.2; and a diluent of 0.9% NaCl, 0.1% CaCl2 (anhydrous), and 0.1% MgSO4·7H2O. HA titers were consistently two- to fourfold higher in the saline with added Ca++ and Mg++ than in DGV. Hemagglutination-inhibition titers of paired human sera were the same in either diluent. It is suggested that the interaction between rubella HA antigen and the red cells of young (less than 1-day-old) chicks may be at least partially ion dependent and that titers are enhanced by increased quantities of divalent cations. 相似文献
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J L Sever 《Teratology》1982,25(2):227-237
The longitudinal study of approximately 60,000 pregnant women was conducted at 14 major medical centers throughout the United States. Clinical data was obtained under prescribed protocols for each of the study women throughout their pregnancy, at delivery, and through the postpartum period. The children were followed with uniform examinations from birth through seven years of age. In addition blood samples were taken from the pregnant women at registration, every two months through pregnancy, at delivery, and six weeks postpartum. Cord blood samples were also taken from the children during the last half of the study. We have used this material from the Collaborative Perinatal Project for the investigation of the role of infections in the production of damage to the fetus and newborn. The frequency of clinically recognizing infection during pregnancy was determined and geographic variation was demonstrated. Serological tests were used to document certain diseases. The frequency of confirmed clinical cases per 10,000 were: rubella, 8; rubeola, 0.6; mumps, 10; varicella-zoster, 5. The epidemiology and clinical findings associated with infections were studied using serological methods. This has provided data on the frequencies of infections such as cytomegalovirus, herpes simplex, mumps, rubeola, respiratory syncytial virus, and others. The study of abnormal pregnancies and matched controls is in progress using serological techniques. A number of specific studies have been reported on infections including rubella, neonatal meningitis, cytomegalovirus, maternal urinary tract infections, and toxoplasmosis. Further testing is now in progress employing more sophisticated laboratory methods and more complete data analysis. 相似文献
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Isolation of measles virus from brain cell cultures of two patients with subacute sclerosing panencephalitis 总被引:24,自引:0,他引:24
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Rubella virus: growth characteristics and stability of infectious virus and complement-fixing antigen 总被引:2,自引:0,他引:2
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