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991.
Cycling virgin female rats were treated with clomiphene citrate (CC) during dioestrus of the reproductive cycle. Animals were sacrificed 2 days after the initial injection and their vaginal tissue was examined by scanning electron microscopy. Animals treated with one dose of CC had an epithelium consistent with a prolonged dioestrus. Treatment with CC for 2 days induced changes in the epithelium that had no resemblance to any normal hormonally controlled event in the vagina. It was found that CC had effects consistent with progesterone alone as well as effects unique to this superovulatory drug.  相似文献   
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Growth and cell proliferation kinetics of hepatoma H-4-II-E and its tissue culture derivative have been studied to establish the characteristics of an in vivo--in vitro solid tumor model. The H-4-II-E line, originating from the Reuber H-35 hepatoma, can be maintained and studied either in cell culture or as a transplantable solid tumor in ACI male rats. In addition it allows for the in vitro assay of cell survival following treatment of animal tumors in situ. In vivo, hepatoma H-4-II-E is rapidly growing tumor with a mean doubling time of 49-2 hr. The cell cyle time is 39-1 hr with a cell loss factor of 0-32. Retrospective examination of tumor specimens obtained during the establishment of the H-4-II-E tumor system demonstrates that both structural as well as cell population changes have occurred. The biological characteristics of the primary tumor (H-35) and an early intermediate stage (H-35tc2) are compared with H-4-II-E and the histopathological, growth and cell kinetic changes are discussed.  相似文献   
994.
The complete behavioral repertoire of male sexual activity can be observed during daily androgen treatment (testosterone propionate, 15 mg/day) of normal ewes ovariectomized as adults. This includes the ejaculatory pattern (deep thrust accompanied by a rapid backwards movement of the head) which is followed by a dramatic decrease in the frequency of sexual interactions, similar to the male's postejaculatory reduction of activity. However, the sexual performances of the genetic females remain lower than those of normal males in ejaculation latency, postejaculation latency, and mount/ejaculation ratio.  相似文献   
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Utilizing horseradish peroxidase as a tracer protein, it is shown that trichogen and tormogen cells have a secretory function. Protein tracer from the haemolymph enters these cells by endocytosis and is transported to the sensillum liquor cavity by transport vacuoles and multivesicular bodies. It is also suggested that closely associated pigment cells may be involved in macromolecular transport.  相似文献   
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