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51.
Immunoreactive met-enkephalin in the canine adrenal; response to acute hypovolemic stress 总被引:1,自引:0,他引:1
L D Farrell T S Harrison L M Demers 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1983,173(4):515-518
Immunoreactive met-enkephalin was measured in the adrenal, kidney, liver, and intestine of the dog using radioimmunoassay. Adrenal tissue concentrations were 20 to 200-fold higher than the other tissues studied. In response to acute hypovolemic stress, the concentration of met-enkephalin in the adrenal vein of the dog increased 6-fold over basal peripheral arterial levels. These results suggest that the canine adrenal gland is a rich source of this opioid peptide and that the adrenal releases met-enkephalin in response to acute stress. 相似文献
52.
Divalent cation sites in tomato bushy stunt virus. Difference maps at 2-9 A resolution 总被引:5,自引:0,他引:5
Difference electron density maps, using as few as four 1/2 degrees oscillation photographs, have been computed for tomato bushy stunt virus crystals soaked in EDTA. GdCl3 and silicotungstate. The maps define a double divalent cation site, responsible for regulating expansion of the virus particle, as well as sites for binding tungstate anions. 相似文献
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Comparison of activity of 25-hydroxycholecalciferol and dihydrotachysterol in the thyroparathyroidectomized rat 总被引:1,自引:0,他引:1
55.
Unstable alleles at three unlinked loci (delilah, nivea and pallida) can mutate somatically to allow the production of clones of pigmented cells (“flakes”) in particular parts of the corolla. The size of the flakes depends on the timing of the mutations during the development of the flower. 相似文献
56.
Selective precipitation of ribonucleic acid from a mixture of total cellular nucleic acids extracted from cultured mammalian cells 下载免费PDF全文
P. R. Harrison 《The Biochemical journal》1971,121(1):27-31
A simple and reproducible method is described for precipitating RNA selectively from total mammalian-cell nucleic acids extracted by the phenol-sodium dodecyl sulphate procedure at pH8.0. Under specified conditions bulk RNA is precipitated almost quantitatively whereas bulk DNA remains in solution. Minor components of RNA (detected by pulse-labelling and chromatography on methylated albumin-kieselguhr) and rapidly labelled components of DNA containing single-stranded regions are also precipitated. The usefulness of the method is discussed in the context of isolating separately both RNA and DNA from cultured cells that are difficult to obtain in quantity. 相似文献
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S-(+)-3,4-Dihydroxybutylphosphonic acid, an isosteric analogue of sn-glycerol 3-phosphate, was synthesized stereospecifically and shown to be an effective substrate for rabbit muscle glycerol 3-phosphate dehydrogenase (sn-glycerol 3-phosphate-NAD(+) oxidoreductase, EC 1.1.1.8). Non-isosteric phosphonate analogues of sn-glycerol 3-phosphate showed neither substrate nor inhibitory activity with the enzyme. 相似文献
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