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971.
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975.
Absorption spectra of 8–phenylazolilolidine and eleven para–substituted derivatives have been determined for solutions in ethanol and ethanolic hydrogen chloride. The pronounced bathochromic shifts and increases in intensity of the first band observed for the corresponding julolidine analogues, relative to the appropriate derivatives of 4–dimethylaminoazobenzene, are somewhat reduced with the lilolidine compounds. The difference in frequency between the absorption maxima of the dyes and their azonium salts correlates well (r=0. 993) with the unmodified Hammett values of the substituents. The lilolidine dyes are suitable for transfer printing, but show poor light–fastness properties on synthetic–polymer fibres. 相似文献
976.
WA Marshall 《Canadian Metallurgical Quarterly》1976,52(612):620-624
The production of gonadal steroids in the perinatal period may have an important influence on the later development of the hypothalamo-pituitary-gonadal axis. In the prepubertal period there is an increased output of gonadal steroids and of androgens from the adrenal cortex, with a further increase as the secondary sex characters develop. The precise role of individual steroids in the maturation of the reproductive system and of the neuroendocrine regulating mechanisms will probably remain unclear unless conclusions are based on longitudinal studies in which hormone production is related precisely to different parameters of sexual development and somatic growth. 相似文献
977.
WA Yost 《Canadian Metallurgical Quarterly》1976,60(1):178-181
The catabolic phase of thyroid secretion --thyroglubulin (Tg) uptake and hydrolysis, release of hormones--has been investigated in vitro, by incubating thyroid slices with 0.1% labelled Tg, in cases of isolated adenomas. Twenty-two specimens were examined: 11 cold follicular adenomas, 5 hot nodules from euthyroid patients, 2 untreated toxic adenomas, and 4 pretreated toxic adenomas. The results were compared with those obtained in 11 specimens of normal tissue. Tg pinocytosis (the amount of Tg taken up by the slices per mg of tissue) was severely impaired in all the non-toxic nodules, cold or hot, i.e., whatever the in vivo activity of the thyroid iodide pump. In toxic adenomas, every step of the catabolic hormonogenesis was activated: high pinocytotic activity, increased Tg hydrolysis, and the discharge of hormonal products; in pretreated cases, the whole process was slowed down. Enzymic activity of the acid hydrolases, beta-galactosidase and cathepsin, was elevated in all the nodules so far investigated, particularly in the toxic adenomas. 相似文献
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