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Robert Rosen 《Bulletin of mathematical biology》1960,22(2):199-205
An error appearing in the proof of Theorem 4 of a previous paper of the author’s (1959,Bull. Math. Biophysics,21, 289–97) is pointed out, and a new proof of the theorem is supplied. We also obtain a corollary from Theorem 3 ofloc. cit. which reveals the existence of a hitherto unrecognized class of codes. 相似文献
57.
There are at present two opposing points of view on problems of dealing with the intersexed patient (not the typical homosexual or transvestite) who has clearcut anatomical or biochemical qualities of the opposite sex. The first is that in the growing child or adult coming for treatment, the sex the patient should adopt is the summation of somatic sex. The other is that the sex role should be assigned according to the predominant psychological identification already present.A case history of a middle-aged pseudohermaphrodite, castrated in youth but raised from birth as a female and living thus in “homosexual” relations with women until examined and interviewed at UCLA Medical Center is presented to illustrate the psychological problems in sexual identity with which the patient had to cope.Psychiatric investigation revealed how confused the patient''s sex identity was until treatment by a team consisting of psychiatrist, psychologist and endocrinologist permitted the patient, even at so late a date, finally to establish what his gender is. The patient was able, despite early rearing as a female and a castrating operation, to swing to a more masculine identification. This was possible because of some uncertainty of sexual role from an early age. 相似文献
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Kern, Jerome (Pacific Research Section, Honolulu, Hawaii), and Leon Rosen. Identification of enteroviruses by hemagglutination-inhibition. J. Bacteriol. 91:1936-1942. 1966.-Approximately 40% of a group of 906 enterovirus isolates cytopathic for monkey cell cultures were found to possess hemagglutinins for human erythrocytes when tested at temperatures of 4 and 37 C and at pH 5.8 and 7.3. The hemagglutinating isolates could be classified by relatively simple techniques into 18 serotypes. Four of these serotypes, echovirus type 24 and coxsackievirus B types 1, 5, and 6, had not previously been known to include hemagglutinating strains. One serotype, Toluca-3, represented a previously unrecognized enterovirus, and two other serotypes may also represent previously unrecognized enteroviruses. 相似文献
59.
Relative contribution of promoter and intragenic sequences in the hormonal regulation of rat beta-casein transgenes 总被引:1,自引:0,他引:1
In order to identify DNA sequences responsible for the regulation beta-casein gene expression, lines of transgenic mice bearing the entire rat beta-casein gene and two rat beta-casein promoter chloramphenicol acetyltransferase (CAT) fusion genes have been established. All three transgenes have been shown previously to be regulated in a tissue- and stage specific manner. To investigate the relative contribution of promoter and intragenic sequences in the hormonal regulation of the beta-casein gene, mammary explant cultures derived from these lines of mice have now been performed, and the effects of PRL and glucocorticoids on transgene as compared with endogenous beta-casein gene expression have been quantified. After the addition of PRL to cultures performed in the presence of insulin and glucocorticoids, a 25- to 40-fold induction of endogenous mouse beta-casein mRNA was observed after 48 hr. A comparable greater than 25-fold induction of transgene expression after PRL addition was observed in explant cultures derived from a line of mice expressing the entire rat beta-casein gene. In contrast, PRL addition elicited only a 1- to 4.5-fold increase in CAT activity in cultures derived from two lines of mice bearing casein-CAT fusion genes with either 524 or 2300 base pairs of 5'-flanking DNA. In the presence of insulin, glucocorticoid or PRL addition alone increased endogenous beta-casein gene expression 2- to 2.5-fold and 5- to 10-fold, respectively, but only a 1.2- to 2.5-fold induction of CAT activity was observed for each hormone.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献