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排序方式: 共有1006条查询结果,搜索用时 15 毫秒
981.
982.
Morse SS 《Science (New York, N.Y.)》2008,319(5868):1351
983.
A significant potentiation of the antitumor action of 5-fluorouracil in rats bearing the Flexner-Jobling carcinoma is produced by the intraperitoneal administration of large doses of glucose. 相似文献
984.
BZR1 is a transcriptional repressor with dual roles in brassinosteroid homeostasis and growth responses 总被引:3,自引:0,他引:3
He JX Gendron JM Sun Y Gampala SS Gendron N Sun CQ Wang ZY 《Science (New York, N.Y.)》2005,307(5715):1634-1638
985.
Bissell M Diamond MC Ellman GL Krueger AP Orenberg EK Sigel SS 《Science (New York, N.Y.)》1981,211(4487):1114-1116
986.
Phillips FM Zreda MG Smith SS Elmore D Kubik PW Sharma P 《Science (New York, N.Y.)》1990,248(4962):1529-1532
Deposits from mountain glaciers provide an important record of Quaternary climatic fluctuations but have proved difficult to date directly. A chronology has been obtained for glacial deposits at Bloody Canyon, California, by measurement ofthe accumulation of chlorine-36 produced by cosmic rays in boulders exposed on moraine crests. The accumulation ofchlorine-36 indicates that episodes of glaciation occurred at about 21, 24, 65, 115, 145, and 200 ka (thousand years ago). Although the timing of the glaciations correlates well with peaks of global ice volume inferred from the marine oxygen isotope record, the relative magnitudes differ markedly. The lengths of the moraines dating from 115 ka and 65 ka show that the early glacial episodes were more extensive than those during the later Wisconsin and indicate that the transition from interglacial to full glacial conditions was rapid. 相似文献
987.
988.
989.
Patil SB Ghadyale VA Taklikar SS Kulkarni CR Arvindekar AU 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(1):85-90
Spices are extensively used to enhance the taste and flavor of foods and are known to possess several medicinal properties.
Myristica fragrans, Parmelia perlata, Illicium verum, Trachyspermum copticum and Myristica malabarica, the commonly used spices in India were assessed for antidiabetic activity in streptozotocin induced diabetic rats. In the
in vitro insulin secretion studies on isolated islets of Langerhans, M. fragrans, T. copticum and M. malabarica showed dose dependent insulin secretion. At 1 mg/ml, P. perlata showed significant in vitro alpha-glucosidase inhibitory activity with IC50 value of 0.14 mg/ml followed by M. malabarica (0.64 mg/ml), I. verum (0.67 mg/ml), M. fragrans (0.85 mg/ml) and T. copticum (0.92 mg/ml). The DPPH free radical scavenging activity of the extracts at a concentration of 1 mg/ml was as M. malabarica (90.45%), M. fragrans (89.89%), I. verum (87.22%), P. perlata (76.70%) and T. copticum (38.14%). P. perlata showed the highest phenolic content (i.e., 118.5 mg gallic acid equivalents/g) followed by M. malabarica (84.13 mg gallic acid equivalents/g). M. malabarica showed the highest flavonoid content (i.e., 38.35 mg quercetin equivalents/g). Regular use of these spices may prevent postprandial
rise in glucose levels through inhibition of intestinal alpha-glucosidase and may maintain blood glucose level through insulin
secretagogue action. 相似文献
990.
Huang GJ Lai HC Chang YS Sheu MJ Lu TL Huang SS Lin YH 《Journal of agricultural and food chemistry》2008,56(9):2989-2995
A cDNA encoding a small cysteine-rich protein designated defensin (SPD1) was isolated from sweet potato storage roots. On the basis of the amino acid sequence similarity and conserved residues, it is suggested that SPD1 is a member of the plant defensin family. Recombinant SPD1 protein overproduced in Escherichia coli was purified by Ni (2+)-chelated affinity chromatography. A recombinant protein from the storage root cDNA clone effectively inhibited the trypsin activity in a dose-dependent manner. Both the corresponding mRNA and protein level were found to be highest in the storage roots, followed by sprout. SPD1 reduced dehydroascorbate (DHA) in the presence of glutathione to regenerate l-ascorbic acid (AsA). However, without glutathione, SPD1 has very low DHA reductase activity, and AsA was oxidized by AsA oxidase to generate monodehydroascorbate (MDA) free radical. MDA was also reduced by SPD1 to AsA in the presence of NADH, mimicking the MDA reductase catalyzed reaction. These data suggest that SPD1 has both DHA reductase and MDA reductase activities. SPD1 was also shown to inhibit the growth of both fungi and bacteria. SPD1 is apparently the first reported plant defensin exhibiting DHA and MDA activities in vitro. 相似文献