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971.
ES Smith 《Canadian Metallurgical Quarterly》1977,73(6):210-211
972.
Infants born in New England with congenital heart defects were examined for association with time of year or population density. Moderate seasonal peaks in births were noted for complex ventricular septal defect, malposition defects, and transposition of the great arteries. Positive associations with population density were found for pulmonary atresia with ventricular septal defect, ventricular septal defect with secondary anomalies, and tricuspid atresia. 相似文献
973.
The response of virgin male and female golden hamsters to young was studied. In contrast to most species, males are more likely to carry pups than are females. All males carried pups, but approximately 50% of females cannibalized the young. The females that did not cannibalize the pups carried them with less hesitation and after shorter latencies than did the males. The response of females to young was not correlated with the aggressiveness displayed toward adult males during separate tests. Tests with gonadectomized females indicated that the maintenance of pup-killing behavior is not dependent on concurrent gonadal hormones. Progesterone injections did not significantly increase pup killing in males that had previously carried young. Speculations on the adaptive significance of the male and female hamster's response to pups are presented. 相似文献
974.
This article reports on phenomenological research designed to discover how caring was taught in a nursing education program. The basic questions were: 1) What is the meaning of caring to the faculty and students; 2) How do the faculty communicate this meaning to the students; and 3) How does this meaning shape the experience of the students? Data were collected from a small associate degree nursing program using: a) semi-structured interviews with all faculty and a selected group of students, b) classroom observations, and c) review of documents. Data were analyzed for and found to have content explaining the meaning of caring, how caring was being taught, and what students were learning about caring as the essence of nursing. Implications derived speak to the need for faculty and administrators to have caring as a way of being if they wish to communicate caring as the essence of nursing to students. 相似文献
975.
Fourty-four primary brain tumors were studied by immunohistochemistry. 29 (67.2%) expressed HLA-Dr. The incidence and number of tumor cells positive for HLA-Dr correlated with the histological type of brain tumor and increased with the degree of malignancy. The mononuclear cells infiltrating in these tumors were mostly CD45ROT cells and macrophages. The former consisted mainly of CD4 and CD8 subsets. The numbers of CD45RO+ and CD8+ T cells in HLA-Dr-group were more than any of the HLA-Dr+, +2, +3 groups. The numbers of CD4 subset and macrophages were not affected by the level of HLA-Dr expression. These results suggest that the HLA-Dr expressed by brain tumor cells selectively inhibit CD8 subset which participates in immunoreaction against brain tumors in situ. 相似文献
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Notechis scutatus scutatus venom contains several toxic acidic proteins called HTa-i which promote hypotension and hemorrhage in mice. They have apparent mol. wts in the 18,000-21,000 range, i.v. LD50 values between 0.5 and 1.5 micrograms/g, and no detectable phospholipase, arginine esterase, proteolytic or hemolytic activities. A polyclonal antibody raised against HTg binds to other purified proteins, suggesting that they are isoforms of the same protein. Many other elapid crude venoms contain proteins which recognize the polyclonal antibody raised against HTg. Crotalid and viperid crude venoms do not recognize this antibody, although some of their component proteins are known to exhibit hypotensive and hemorrhagic activities. A combination of gel-filtration on Sephacryl S-200, cation-exchange and anion-exchange chromatography allows isolation of the N. s. scutatus proteins in high purity. They are the first hypotension-inducing proteins to be purified from an Australian elapid. 相似文献
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