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1.
Regional localization of the hepatocyte growth factor (HGF) gene to human chromosome 7 band q21.1. 总被引:2,自引:0,他引:2
Hepatocyte growth factor (HGF) is a polypeptide involved in liver regeneration. Its amino acid sequence and gene structure are similar to those of coagulation-related serine proteases. We have used a cDNA clone of HGF and flow-sorted human chromosomes to assign this gene to chromosome 7. Fluorescence in situ hybridization of the HGF genomic clones to human metaphase chromosome spreads showed the localization of this gene to 7q21. Estimation of fluorescent signals relative to arbitrary reference points (ARPs) allowed further localization to 7q21.1. 相似文献
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Viable yellow obese mice (Avy/a) were treated for 10 days with 5, 15, 50 or 150 micrograms/d of either alpha-MSH or desacetyl-MSH. The half-maximal effect on weight gain occurred with a dose of 5 micrograms/d for desacetyl-MSH and at a 30 fold higher level of 150 micrograms/d for alpha-MSH. In contrast, the half-maximal stimulation of eumelanin production by alpha-MSH occurred at 15 micrograms/d and with desacetyl-MSH at 150 micrograms/d, a 10-fold increase. Desacetyl-MSH produced a dose-related increase in the weight of muscle, as well as white and brown adipose tissue. Desacetyl-MSH and alpha-MSH both increased plasma corticosterone concentrations, but desacetyl-MSH was more potent. In a 2 x 2 factorial designed study, body weight was significantly increased in viable yellow mice only by treatment with desacetyl-MSH but in the lean animals, both alpha-MSH and desacetyl-MSH increased body weight. Food intake was significantly different between genotypes, and was stimulated by desacetyl-MSH. These studies demonstrate potent differences in biological actions on food intake, body weight, and a variety of organ weights between acetylated and desacetylated forms of MSH. 相似文献
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T Tobe S Minoshima S Yamase N H Choi M Tomita N Shimizu 《Cytogenetics and cell genetics》1991,57(4):193-195
SP-40,40 is a serum glycoprotein consisting of two different subunits (alpha and beta) assembled into a dimer by disulfide bonds. Northern blot hybridization, using total RNA from several cell lines, showed that SP-40,40 is expressed in glioblastoma and testicular tumor cells, as well as hepatoma cells. Spot blot hybridization of flow-sorted human chromosomes, using a SP-40,40 cDNA fragment as a probe, localized the gene for SP-40,40 to human chromosome 8. This gene has been given the designation CLI, for complement lysis inhibitor, by the Human Gene Nomenclature Committee. 相似文献
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T Matsuno T Maoka M Katsuyama T Hirono Y Ikuno M Shimizu T Komori 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,85(1):77-80
New luteins, lutein F [(3R,3'R,6'S)-beta,epsilon-carotene-3, 3'-diol] and lutein G [(3S,3'R,6'S)-beta,epsilon-carotene-3,3'-diol] have been isolated from marine fishes. 相似文献
6.
Satoru Tamura Nobuhiro Shimizu Katsuaki Fujiwara Masafumi Kaneko Tominori Kimura Nobutoshi Murakami 《Bioorganic & medicinal chemistry letters》2010,20(7):2159-2162
Rational design by the MO calculation disclosed 5,6-dihydrovaltrate (2) as the bioisostere of valtrate (1), the Rev-export inhibitor with anti-HIV activity. The synthesis of 2 was accomplished by ingenious use of asymmetric Diels–Alder reaction and stereoselective epoxidation associated with the adjacent hydroxyl group. Because of similar biological potency to 1, the analog 2 should be recognized as a promising scaffold for new anti-HIV agents with an unprecedented mechanism of action, inhibition for nuclear export of Rev protein, in the conventional remedy. 相似文献
7.
The splenic lymphoid tissue of mice reared in a conventional environment regressed with increasing age. Immunogloblin G positive plasma cells gathered along the penicilli in the senile spleen as well as in the adult control spleen. The number of plasma cells around the penicilli showed no difference in the senile spleen as compared to the adult spleen. Since mature plasma cells remain in the lymph node for a short time only and seldom divide there, our results indicate that the transformation from B lymphocyte to plasma cell is not affected by age. 相似文献
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The mechanism was studied of the overshoot of calcium accumulation in fragmented sarcoplasmic reticulum (FSR) which is observed when the active transport of calcium into FSR is performed in the presence of thymol; the amount of calcium in FSR increases steeply during the first minute of the reaction and then decreases markedly. In contrast to this behavior, the amount of calcium in FSR increases monotonically and then reaches saturation in the absence of thymol. It is shown that the amount of calcium accumulated in FSR is determined by the balance between the rapid influx and efflux of calcium, and that both processes are depressed by thymol. The overshoot of calcium accumulation can be explained as follows: thymol so markedly depresses the efflux of calcium uncoupled with Ca2+-ATPase activity that the amount of calcium is increased in FSR in spite of partial deactivation of Ca2+-ATPase. However, the state of the FSR membrane is rapidly changed when the concentration of accumulated calcium exceeds a certain critical value. Concomitant with this change, the calcium permeability of the membrane is increased, leading to a decrease in the amount of accumulated calcium. The effects of magnesium and temperature on the overshoot of calcium accumulation can be accounted for by this proposed mechanism. 相似文献