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211.
Summary Rat serum contains natural 1,5-anhydroglucitol. Injected or orally administered 1,5-anhydroglucitol was efficiently reabsorbed by the renal tubuli via a mechanism which had a saturation point at high serum 1,5-anhydroglucitol levels. The compound had a slow turnover rate in the body; its half-life is approximately 3 days. The compound was readily absorbed in the gut when administered orally.  相似文献   
212.
Summary Ethanol was administered i.p. to adult roosters during hormonally induced vitellogenin synthesis. At moderate doses, ethanol had no influence on the synthesis of vitellogenin nor did it cause alterations in the size distribution of liver polyribosomes.This was supported in part by a grant from the Foundation for Alcohol Studies, Finland.  相似文献   
213.
Summary By electron microscopic examination of a solid, chiefly scirrhous mammary cancer, 3 kinds of unusual nuclear inclusions were found: (a) Electron dense particles of a 54–80 nm diameter, whose outlines appear mainly hexagonal, which points at an icosahedral structure, (b) Clusters of granules with a diameter of 200–300å, respectively 300–400å, at whose circumference the larger particles appear, (c) Bundles of filaments in close association and continuous with the granules. In all 3 nuclear inclusions there are subunits of 40–45å. The comparison between these results and experiments published suggest that these nuclear inclusions are (a) virus particles, (b) virus at an early stage of development and (c) virus protein subunits.  相似文献   
214.
Bromothricin     
Summary Streptomyces antibioticus (Waksman andWoodruff)Waksman andHenrici 1948, strain Tü 99, produced Bromothricin instead of Chlorothricin, when it was grown in a nutrient medium containing 0.5% potassium bromide. The properties of bromothricin are very close to those of chlorothricin. Its nature was elucidated by degradation to methyl 5-bromo-2-methoxy-6-methylbenzoate.  相似文献   
215.
Peroxisomes are single-membrane-bound organelles present in virtually all eukaryotic cells. They are involved in numerous metabolic processes, both catabolic and anabolic, including β-oxidation of very long chain fatty acids, metabolism of hydrogen peroxide, plasmalogen biosynthesis and bile acid synthesis. In several genetic diseases, there is either isolated deficiency of a specific peroxisomal protein (single-protein deficiencies) or a defect in the formation of the organelle with loss of multiple peroxisomal functions (peroxisome biogenesis disorders). X-linked adrenoleukodystrophy is an example of the former, and the Zellweger spectrum of the latter. Peroxisome biogenesis disorders are inherited in an autosomal recessive manner and result from mutations in any of at least 12 PEX genes that encode peroxins. This article reviews the peroxisomal system, the clinical, biochemical and molecular aspects of peroxisomal disorders, and discusses recent scientific advances in the understanding of peroxisome biogenesis. Received 16 October 2001; received after revision 2 January 2002; accepted 3 January 2002  相似文献   
216.
Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ~ 2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10??), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation.  相似文献   
217.
Summary Squirrel monkeys learned to avoid hypoxia by pressing a bar. Each bar-press replaced the noxious gas mixture with normal air for 3 sec. The data further indicated that O2 itself has no positive reinforcing effect.  相似文献   
218.
Summary A feeding test over the whole life span of 800 Sprague-Dawley rats with commercial starters for camembert- and blue-cheese, with commercial cheese and test cheese, as well as subcutaneous application of the mycelia, did not yield any indication for a detrimental or carcinogenic effect.The authors wish to thank the Federal Minister for Youth, Family and Health in Bonn for support of this work.  相似文献   
219.
Monoclonal antibodies against antigens on breast cancer cells   总被引:1,自引:0,他引:1  
Summary Of 360 mAb obtained in a cell fusion experiment with the spleen cells of a mouse immunized with a mixture of different human breast carcinoma cells lines, 30 mAb were selected which reacted more strongly with tumor cells than with (noncancerous) fibroblasts. Theses mAb were tested for reactivity with additional types of cancerous and noncancerous tissues. Two mAb showed high tumor selectivity, but the corresponding epitopes on individual tumor cells were heterogeneously expressed. The mAb will be evaluated for in vivo applications.  相似文献   
220.
Summary Chlamydocin, a potent cytostatic agent against cultured mammalian cells, and HC-toxin, a host-specific phytotoxin, are cyclic tetrapeptides containing the same epoxide -amino acid. We show here that these compounds have reciprocal biological activity; HC-toxin is cytostatic against cultured mastocytoma cells, and chlamydocin has host-specific toxin activity against maize. Chlamydocin and another related cyclic peptide, Cyl-2, are less host-specific than HC-toxin because maize tolerant to HC-toxin is more sensitive to chlamydocin and Cyl-2.  相似文献   
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