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91.
92.
Restriction endonucleases   总被引:5,自引:0,他引:5  
  相似文献   
93.
We have reported our experience with splenectomy in fifty patients less than fourteen years old. The indications, results, and complications were enumerated. These data were then correlated with the recent literature regarding pediatric splenctomy. Of special note is the problem of immunologic incompetency associated with splenectomy in the patients less than five years old.  相似文献   
94.
Whole ovaries from 16-day fetal mice were cultured for 6 to 20 days and then transplanted to the kidneys of ovariectomized adult mice where they remained for one to four weeks. After three weeks in the host's kidneys, many follicles developed within the transplants and became vesiculated. Many of the oocytes within these follicles had formed the first metaphase spindle of meiosis and several had completed the first polar body. Host mice bearing transplants that contained vesiculated follicles showed uterine stimulation and keratinization of their vaginae. However, ovaries that had been in culture for more than ten days before transplantation showed a limited response to the gonadotropins and never matured sufficiently to stimulate the host's reproductive tract. No ovulations occurred in any of the transplants.  相似文献   
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This paper describes a study of the physico-chemical and radioimmunological properties of three antialdosterone antisera which permitted practical conclusions to be drawn. By its high degree of specificity, anti-aldo-3-oxime-BSA constitutes the most useful antiserum for the clinical assay of aldosterone. The principal advantage of this antiserum is that it allows both urinary and blood aldosterone radioimmunoassay without the necessity of including a chromatographic step. No problems arise with the blanks. This work also includes the study of two anti-deoxycorticosterone antisera. The aldosterone and deoxycorticosterone values, obtained from normal subjects under various physiological conditions, are in agreement with the values given in the literature.  相似文献   
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Studies of the effect of cholecystokinin (CCK) on hepatic elimination of intravenously administered iopanoate and on gallbladder opacification were performed using nonoperated dogs with intact enterohepatic circulation and normal endogenous bile salt pool. Intravenous administration of CCK (3 units/kg) resulted in a 32% increase in apparent transport maximum (maximum rate of elimination) of iopanoate and earlier and enhanced gallbladder opacification. This increase in apparent transport maximum was abolished by cholecystectomy, indicating that the increase was a result of the release of bile salts from the gallbladder rather than a direct effect of the hormone on the hepatic elimination of iopanoate. The early gallbladder opacification and increased density of contrast material in the gallbladder were related to CCK-induced emptying of the gallbladder and subsequent filling with opacified bile.  相似文献   
100.
The time course of skin tumor induction was determined in hair-clipped inbred agouti C3Hf mice irradiated three times per week with a medium-pressure quartz-mercury lamp; 4 different UV doses were used. Although the ears were also exposed to the radiation, in the 3 groups given the highest doses no ear tumors were observed by the time each animal had developed at least 1 tumor on its back. No tumors were found in the animals receiving the lowest UV dose. In the group receiving the highest dose, males developed tumors earlier than did females; this trend continued in the lower dose groups. Many tumors that developed in the back skin were well-differentiated squamous cell carcinomas. Others were less well-differentiated squamous cell carcinomas. Others were less well defined so that the cell of origin was difficult to determine. In the group receiving the highest UV dose, the squamous cell carcinomas were few, whereas at the lower doses they predominated.  相似文献   
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