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1.
To reveal the difference of molecular property between structurallysimilar odorless and odoriferous musk compounds, 10 pairs ofbenzenoids (monocyclic-, dicyclic- and tricyclic-) were examined.Molecular structures of all compounds were optimized by MNDO(modified neglect of diatomic differential overlap) consideringconformation. Parameters effective in discriminating two groups,group A of 10 odorless compounds and group B of 10 musk odorcompounds, were searched from 34 candidate parameters by adaptiveleast squares. The best three parameters found were log P value(octanol/water partition coefficient), the longest side lengthof hexahedron circumscribing a molecule, and the parameter whichexpresses structural hindrance to the functional group whena molecule approaches the receptor site. The two groups of compoundswere completely discriminated using these three parameters. 相似文献
2.
Characterization of the cytoplasmic inclusion bodies of the spleens from patients with adult form Gaucher's disease 总被引:1,自引:0,他引:1
The twisted tubular cytoplasmic inclusion bodies were isolated from spleens of four patients with adult form Gaucher's disease. The chemical composition of the CIB (cytoplasmic inclusion bodies) was as follows: proteins, 10%, cholesterol, 10%, phospholipids, 10%, glycolipids, 70%. More than 90% of glycolipids from CIB were glucosylceramide. The structural protein profile of these bodies was examined by SDS-polyacrylamide disc gel electrophoresis on a semimicro-scale (s-PAGE). A similar protein composition which included two glycoproteins was found in all the four cases. The tubular structure of the bodies was changed to a small and round form by the treatment with 1 mM EDTA-Na2 which removed some structural proteins from the bodies. This indicated that some proteins might have an important role in maintaining the tubular structure of CIB. 相似文献
3.
We examined the hypothesis that activation of the muscle metaboreflex during dynamic exercise would augment influences tending to cause a rise in arginine vasopressin, plasma renin activity, and catecholamines during dynamic exercise in humans. Ten healthy adults performed 30 min of supine cycle ergometer exercise at approximately 50% of peak oxygen consumption with or without moderate muscle metaboreflex activation by application of 35 mmHg lower body positive pressure (LBPP). Application of LBPP during the first 15 or last 15 min of exercise increased mean arterial blood pressure, plasma lactate concentration, and minute ventilation, indicating an activation of the muscle metaboreflex. These changes were rapidly reversed when LBPP was removed. During exercise at this intensity, LBPP augmented the release of arginine vasopressin and catecholamines but not of plasma renin activity. These results suggest that, although in humans hormonal responses are induced by moderate activation of the muscle metaboreflex during dynamic exercise, the thresholds for these responses may not be uniform among the various glands and hormones. 相似文献
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Anaerobic biodegradability of polyvinyl alcohol 总被引:4,自引:0,他引:4
Summary Biodegradability of polyvinyl alcohol (PVA) under anaerobic conditions was demonstrated using anaerobic river sediments and anaerobically treated activated sludge from a sewage treatment plant. PVA having molecular weights of 2000 and 14000 was over 60% biodegraded as determined by TOC. 相似文献
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Hasan Sharmin Asakawa Shuichi Watabe Shugo Kinoshita Shigeharu 《Marine biotechnology (New York, N.Y.)》2021,23(5):821-835
Marine Biotechnology - The human sarcomeric myosin heavy chain gene MYH14 contains an intronic microRNA, miR-499. Our previous studies demonstrated divergent genomic organization and expression... 相似文献
8.
Shuichi Ishida 《Bioscience, biotechnology, and biochemistry》2013,77(8):800-806
2-Bromoethylthiobenzenes were toxic to the eggs of Tetranychus telarius (L.) depending on the permeability and the reactivity of the compounds. It was suggested by the means of ρ-σ-π analysis that the reactivity depends on the electron-donating power of the sulfur atom to the site of action or the carbon atom of carbon-bromine linkage. 相似文献
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