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171.
Summary Valine decarboxylation was significantly increased and leucine decarboxylation was significantly decreased in rat liver slices following hypophysectomy. In both normal and hypophysectomized rats decarboxylation of leucine exceeded that of valine in slices whereas the reverse was observed with the respective keto acids and mitochondria.Acknowledgments. This study was supported by the National Institutes of Health and the Samuel A. Berger Foundation.  相似文献   
172.
Summary Oral administration of p-coumaric acid to estrogen-primed immature female mice exerts neither estrogenic nor anti-estrogenic activity, but when it is administered to cyclic female mice in single dose at proestrus or in repeated doses, induces alteration in estrus cycle, ovarian and uterine weight and structure.The authors wish to thank Dr S. C. Pakrashi and his associates of Medicinal Chemistry Department for isolating the compound. Thanks are also due for granting Senior Research Fellowship to P.P. and Junior Research Fellowship to S.N.K. respectively.  相似文献   
173.
Summary Larvae of the German cockroach exposed to filter paper impregnated with juvenile hormone (JH) active substance contain, at the middle of the last instar, about one-hundredth of the dose applied to 1 cm2. The amount of metabolized substance rises sharply before and disappears rapidly after the ecdysis into the supernumerary instar.Acknowledgments. We wish to express our thanks to Prof. Dr H.A. Schneiderman, Dr W. Vogel and Dr P.A. Vonder Mühll for stimulating discussion and to Mr M. Gruber for correction of the text.  相似文献   
174.
Summary Unlike the highly porphyrinogenic fungicide hexachlorobenzene, hexabromobenzene was a poor inducer of porphyria. Similarly, 1,2-dibromobenzene and 1,2,4-tribromobenzene, while causing small increases in hepatic porphyrins, did not increase ALA synthetase or the urinary excretion of porphobilinogen (PBG), aminolevulinic acid (ALA) or porphyrins.Supported by grant R805070 from the US Environmental Protection Agency.  相似文献   
175.
Summary Concentration of copper in seminal plasma was found to be less than that of normal in cases of oligospermia and azoospermia. It was more in oligoasthenospermia and asthenospermia when compared with that normal. Chances of initiation of sperm motility by copper is discussed alongwith the inhibitory role it plays.Acknowledgment. Authors are thankful to Dr. A. R. N. Setalwad, Assistant Professor in Preventive and Social Medicine for the statistical analysis of the study he did.  相似文献   
176.
Summary Antibodies against hyperglycemic hormone (CHH) ofCarcinus were raised in rabbits by injection of extract from sinus glands which contain high concentrations of CHH. The antiserum neutralizes the biological activity of CHH and binds125J-CHH. A RIA for CHH was established and was used to measure the hormone content of sinus glands.Dedicated to Prof. M. Gersch, Jena, on the occasion of his 70th birthday.This study was supported by the Deutsche Forschungsgemeinschaft (Ke 206/2).We thank S. Grabig. E. schmid and B. Reichwein for expert technical assistance, and Dr D. Breitig and G. Kegel for critical discussions.  相似文献   
177.
Summary In 2 independent samples of low-birth-weight infants the proportion of females and homozygotes for a series of polymorphic systems was higher in light-for-dates than in preterm babies. The observation seems to give support to the hypothesis that homozygosity for normal polymorphisms may decrease in general intrauterine growth rate. Since it is known that survival rate is strongly related to birth weight, a correlation between growth retardation and homozygosity may have a major role in the maintenance of such polimorphisms.We thank Prof. L. Ginzburg for helpful comments.  相似文献   
178.
Summary The addition of 100 g/l NaCl and 200 mg/l nitrofurantoin to 24-h urine samples destined for determination of LH and FSH with haemagglutination tests, proved to be an adequate preservative in comparison to chilling.  相似文献   
179.
Summary Increase of the ionic strength inhibits the catalytic activity of the mitochondrial MDH, reduces substrate inhibition and decreases the affinity of substrates for the enzyme.This work was supported by a grant from the Conselho Nacional de Desenvolvimento Tecnológico (CNPq), Brazil.  相似文献   
180.
Summary The D-galactose specific lectin fromViscum album L. reacts with serum proteins that contain the corresponding D-galactopyranosyl residues. By affinity chromatography of human serum on lectin-sepharose IgM, 2-macroglobulin, haptoglobin and -lipoprotein were quantitatively retained. Only parts of IgA, IgG and transferrin were retarded. The other serum proteins are unbounded as albumin, 1A– and 1C.  相似文献   
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