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51.
52.
Recombinant human interleukin-l (rIL-1) alpha and beta, which have 26% homology in their amino acid sequence, stimulated arachidonic acid metabolism by squirrel monkey smooth muscle cells and rat liver cells; their relative effectiveness, however, varied with the two cells. Recombinant IL-1 alpha was 3 times more effective than rIL-1 beta at stimulating arachidonic acid metabolism by the primate smooth muscle cells. Recombinant IL-1 alpha was 3 times less effective than rIL-1 beta when measured by their capacity to synergistically stimulate arachidonic acid metabolism of rat liver cells in the presence of palytoxin and anti-diuretic hormone (ADH). The rIL-1 alpha and rIL-1 beta also stimulated the release of radiolabelled arachidonic acid from the smooth muscle cells prelabelled with [3H]arachidonic acid. The two recombinant IL-1s have different heat stabilities, again when measured by their capacity to stimulate arachidonic acid metabolism; IL-1 alpha was more heat stable than IL-1 beta. 相似文献
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54.
用多孔强碱型三乙醇胺基聚苯乙烯阴离子交换树脂做为载体,用CNBr与载体上的多羟基作用共价偶联了胰酶。红外光谱表明:其共价偶联反应机理与用CNBr活化多糖类载体并接酶的机理相类似。最适偶联条件研究表明:CNBr用量增多,酶蛋白载量增加。但比活下降。偶联pH为10时,固定化酶有适宜的载量和较高的比活。由于胰酶水解蛋白反应释放出H~+质子,这些质子在载体内积累,使微环境内H~+质子浓度增加,进而使得固定化胰酶的pH—活性曲线在pH9~11范围内未出现下降。在变温和60℃恒温下对固定化酶的热稳定性测试表明:固相酶的热稳定性比天然酶的热稳定性有所提高。 相似文献
55.
Acetylcholine in the posterior hypothalamic nucleus is involved in the elevated blood pressure in the spontaneously hypertensive rat 总被引:1,自引:0,他引:1
Intravenous injection of physostigmine, 40 and 80 ug/kg, in unanesthetized normotensive rats increased systolic blood pressure (SBP) by 21 +/- 3 and 42 +/- 7 mmHg. This pressor response was 80% inhibited by intracerebroventricular (icv) injection of hemicholinium-3 (HC-3), 20 ug. Simultaneous icv injection of HC-3 and choline (365 ug) prevented the inhibition of the pressor response by HC-3. In spontaneously hypertensive rats, injection of HC-3 either icv (20 ug) or bilaterally into the posterior hypothalamic nuclei (1 ug) decreased SBP by about 40 mmHg. The effect of intrahypothalamic HC-3 was completely blocked by simultaneous injection of choline (24.3 ug) into the same site. The hypotensive effect of icv HC-3 was completely blocked by icv choline (243 ug) and was inhibited up to 60% by injections of choline (24.3 ug) into the posterior hypothalamic nuclei. 相似文献
56.
Shu-Yu Yu Bao-Lin Mao Ping Xiao Wei-Ping Yu Ying-Long Wang Chang-Zhi Huang Wang-Qiu Chen Xiang-Zhan Xuan 《Biological trace element research》1990,24(2-3):105-108
This pilot study evaluated the feasibility and effectiveness of conducting a double-blind clinical trial for the prevention of lung cancer with selenium (Se) in Yunnan Tin Corporation, the People's Republic of China, where the incidence rates of lung cancer are extraordinarily high among the miners. Forty healthy miners were randomized to either 300 μg of Se in high Se malt cakes or an identical placebo of malt cakes daily for one year. Subjects consumed their usual daily diet. The low Se concentrations in plasma (0.05±0.008 μg/mL) and hair (0.442±0.085 μg/g) reflected their low dietary Se intake in the control subjects. In Se-supplemented group, the Se status was increased by 178% for serum and 194.8% for hair. The serum GSHpx activity was increased by 155.7%, whereas the lipid peroxide level was reduced by 74.5% compared to the placebo. The results of UDS assay indicated that the lymphocyte DNA damage induced by ultraviolet irradiation and carcinogen 3,4-benzpyrene could be protected by Se supplementation. Se-supplementation did not affect the liver function test (SGPT), as well as the concentrations of hemoglobin, albumin, and cholesterol. Thus, daily intake of 300 μg Se in form of Se-malt as a chemopreventive measure is safe and effective to humans with low Se status. 相似文献
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Biological Trace Element Research - The essential trace elements in 30 traditional Chinese medicines, (24 tonics and 6 nontonics) were determined by proton-induced X-ray emission. The... 相似文献
58.
安徽省达到芒属植物资源及其开发利用 总被引:9,自引:0,他引:9
安徽省芒属植物有3种量变种:五节芒(Miscanthus floridulus)、芒(M.sinensis var. sinensis)、紫芒(M. sinensis var. purpurascens)和荻(M. saccharifl-orus);其中紫芒为本省地理分布新记录。它们的资源量大;如全省仅连片五节芒草地即达260多万亩,一般亩产鲜草1000—2500公斤。芒属植物是利用价值很高的资源禾草:饲用价值“良等”;保持水土能力强;纤维品质优良,为制浆造纸及编织的上等原料;并可药用。最后,提出了开发利用芒属植物资源的几点建议。 相似文献
59.
本文报道,采用气相色谱(GC)分析新发现的野生木里柠檬,和栽培的尤力克柠檬种子油的8种脂肪酸成分,和用常规化学方法对比测定两种柠檬果实中的糖,有机酸和维生素C的含量。研究结果表明,木里柠檬的脂肪酸及其它营养成分与尤力克柠檬相近。 相似文献
60.
中草药“一口钟”的原植物鉴定及其精油的化学成分 总被引:2,自引:0,他引:2
云南,四川等省市售的中草药“一口钟”为蓝桉(Eucalyptus globulus Labill.)的果实.用气相色谱-质谱-计算机联用技术、标准品迭加和毛细管保留指数定性法,对其精油的化学成分进行分析.从分离的65个成分中,鉴定出36个成分,其含量占总组成的93.80%,主要成分是别香树烯(23.37%),1.8-桉叶油素(20.81%)、金合欢醇(9.95%)、α-水芹烯(8.30%)、δ-愈创木烯(5.95%)、δ-蒎烯(4.09%)、β-水芹烯(3.43%)、α-愈创木烯(3.15%)等. 相似文献