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991.
JL López Sendón J Carrillo Kabana J Silvestre García J Calderón Montero 《Canadian Metallurgical Quarterly》1976,29(3):251-257
By reviewing the syndromic manifestation, transsexualism in characterized as a psychiatric entity, apart from homossexualism and transvestism. The two main feasible etiologic causes of transsexualism are discussed: the psychoanalytical hypothesis based upon psycossexual regression with imprinting of maternal figure and the neuroendocrine model which assumes alterations of the gender role identity centers in the hypothalamus. On the grounds of the latter explanation and after the scheme that seems to occure in the Morris syndrome whose cells (XY) do not respond to the masculinizing effect of plasma testosterone, it is proposed that transsexuals should possess detectable or cryptic sex-chromosome mosaicism affecting hypothalamic centers of gender role identity which do not respond to the androgenic secretion produced by primitive gonad. This possibliity explains the excessive prevalence of the syndrome among men, its typical features in the male as well as its sporadic occurrence. Cytogenetic investigation reveals that the frequency (32%) of sex-chromosome mosaicism among 25 transsexuals and 40 normal control people, both groups presenting the proportion of the mosaicism practically null. The karyotypic criterion as a valuable aid in the syndrome diagnosis is considered. 相似文献
992.
993.
A case control study was conducted in Washington County, Md. to assess the possibility that isoniazid might be associated with the production of malignant neoplasms of the urinary tract. One hundred and forty-two cases of bladder cancer and 48 cases of renal cancer were found in the follow-up of a 1963 census population. Each case was matched to two other persons of the same race, sex, and age enumerated in the census. The tuberculosos register for the county was searched to see whether any case or control subject had ever received isoniazid. Two members of the entire study group had a record of isoniazid administration; both were control subjects. No evidence was found to associate isoniazid with cancers of the urinary tract. 相似文献
994.
995.
996.
B Jacotot H Rosenstein M Claire JL Beaumont 《Canadian Metallurgical Quarterly》1975,280(18):2149-2151
The study of the coagulation in rats fed with a balanced diet, including 12% of different animal or vegetable fats, during 6 months, shows that the time of coagulation in rats receiving one of the following oils: palm, sunflower, Canbra, is significantly higher than the ones fed with butter. On the other hand, the coagulation time observed in the groups is correlated with the oleic acid level in the corresponding diet. The results obtained here may lead to important practical applications. 相似文献
997.
998.
A hierarchically-branching system is recommended for classifying published work in the field of cerebral asymmetry, and its rapid retrieval. It can readily accommodate partically everything published since 1965. 相似文献
999.
1000.