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H E Hildebrandt-Stark G J Marcus K Yoshinaga H R Behrman R O Greep 《Prostaglandins》1975,9(2):231-244
Adult female guinea pigs were actively immunized with prostaglandin F-2alpha conjugated to bovine serum albumin (BSA). Control animals, immunized against BSA continued to cycle normally, while the animals immunized against prostaglandin F-2alpha stopped cycling after one to three normal cycles. Laparotomy at 30 days after the last estrus revealed no recently formed corpora lutea. During the remaining 70 days of observation the antibody titer increased to 1:700, accompanied by increasing total serum estrogens (136 pg/ml at day 100) and a slow decline in circulating progesterone levels (0.6 ng/ml at day 100). The ovaries at day 100 contained degenerated corpora lutea and luteinized follicles. The suppression of the estrous cycle in the present experiments was interpreted as resulting from prolongation of luteal function as well as from inhibition of ovulation. 相似文献
604.
Detection and characterization of a functional complex of human immunodeficiency virus type 1 integrase and its DNA substrate by UV cross-linking. 总被引:3,自引:2,他引:1 下载免费PDF全文
To analyze the association of the human immunodeficiency virus type 1 integrase (IN) protein with DNA substrates, we applied a shortwave UV cross-linking method to the in vitro integration system. Three photoadduct bands were detected on sodium dodecyl sulfate-polyacrylamide gels. The appearances of these photoadducts were examined with various substrates and under several incubation conditions. Our data suggest that one of these photoadducts is derived from the sequence- and strand-specific bound state of the early phase of the integration reaction before the 3' processing reaction. We also show that most of the photoadduct complexes are competent for integration even after UV irradiation. 相似文献
605.
The behavior of quail primordial germ cells (PGC) after injection into chick embryos by the intravascular route was examined. The quail (donor) PGC, taken from the bloodstream of quail embryos (recipient) at stage 13-14, were injected into the vitelline vessels of chick embryos (recipient) at stage 15. In the recipient embryos, the PGC of the quail and the chick were histochemically distinguished by a double-staining technique involving a lectin, from Wistaria floribunda (WFA) and the PAS reaction. One day after injection, quail PGC appeared in the prospective gonadal region of recipient chick embryos, being localized among the recipient chick PGC. This result indicates that a staining technique specific for WFA lectin is useful for identification of quail PGC and that quail PGC can be transferred by a vascular route for the production of germline chimeras. 相似文献
606.
The presence of germinal cells outside of the embryonal and fetal gonads of the strepsirhine prosimian Galago crassicaudatus crassicaudatus is described. Forty-three embryos and fetuses from day 26 or 27 of gestational age to near term were studied: more than 90% possessed germinal cells in ectopic sites situated either far from (extragonadal ectopism) or close to the gonads (perigonadal ectopism). The first sites were the walls of the aorta and mesenteric artery, the stroma between the aorta and the cardinal vein, and the retroperitoneal neuroganglia. The second were the mesenchyme dorsal to the gonads and around the vestigia of the mesonephric glomeruli and tubules, and the rete ovarii and testis. The ectopic cells were generally present in conscpicuous numbers, in some animals being more numerous than in the gonads. Those situated far from the gonads underwent degeneration and decreased significantly in numbers during post-embryonal stages of development, while the others remained numerous and functionally active up to near term. While the differentiation of the extragonadal germinal cells after day 60 of gestational age could not be studied due to technical difficulties, the XX and XY cells in perigonadal sites appeared to follow patterns of differentiation identical to those of their entopic counterparts. 相似文献
607.