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131.
Stimulation of phospholipase C by guanine-nucleotide-binding protein beta gamma subunits. 总被引:12,自引:0,他引:12
M Camps C Hou D Sidiropoulos J B Stock K H Jakobs P Gierschik 《European journal of biochemistry》1992,206(3):821-831
We have previously shown that soluble fractions obtained from human HL-60 granulocytes contain a phospholipase C which is markedly stimulated by the stable GTP analogue guanosine 5'-[3-O-thio]triphosphate (Camps, M., Hou, C., Jakobs, K. H. and Gierschik, P. (1990) Biochem. J. 271, 743-748]. To investigate whether this stimulation was due to a soluble alpha subunit of a heterotrimeric guanine-nucleotide-binding protein or a soluble low-molecular-mass GTP-binding protein, we have examined the effect of purified guanine-nucleotide-binding protein beta gamma dimers on the phospholipase-C-mediated formation of inositol phosphates by HL-60 cytosol. We found that beta gamma subunits, purified from bovine retinal transducin (beta gamma t), markedly stimulated the hydrolysis of phosphatidylinositol 4,5-bisphosphate by this phospholipase C preparation. The stimulation of phospholipase C by beta gamma t was not secondary to a phospholipase-A2-mediated generation of arachidonic acid, was prevented by the GDP-liganded transducin alpha subunit and was additive to activation of phospholipase C by guanosine 5'-[3-O-thio]triphosphate. Beta gamma t also stimulated soluble phospholipase C from human and bovine peripheral neutrophils, as well as membrane-bound, detergent-solubilized phospholipase C from HL-60 cells. Stimulation of soluble HL-60 phospholipase C was not restricted to beta gamma t, but was also observed with highly purified beta gamma subunits from bovine brain. Fractionation of HL-60 cytosol by anion-exchange chromatography revealed the existence of at least two distinct forms of phospholipase C in HL-60 granulocytes. Only one of these forms was sensitive to stimulation by beta gamma t, demonstrating that stimulation of phospholipase C by beta gamma subunits is isozyme specific. Taken together, our results suggest that guanine-nucleotide-binding protein beta gamma subunits may play an important and active role in mediating the stimulation of phospholipase C by heterotrimeric guanine-nucleotide-binding proteins. 相似文献
132.
马麝(Moschus sifanicus Przewalski)系著名的药用动物。雄麝腹部有一麝香腺囊,其内分泌物叫麝香。麝香是医药工业和香料工业的重要原料。又是珍贵的出口物资。 1973-1974年作者在青海省尖扎县能科公社的青穆措沟对马麝的生态进行了观察(郑生武、皮南林,1979),同时对麝香腺囊做了解剖研究和麝的数量调查。 相似文献
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135.
杏黄兜兰的花发育过程及引种栽培 总被引:1,自引:0,他引:1
通过形态解剖研究了杏黄兜兰花的发育过程,发现杏黄兜兰5月份发育出花序原基,6~7月份发育出花序鞘,7~8月份发育出苞片,8月底至9月完成花器官形态分化过程。形态分化完成后杏黄兜兰的花器官继续快速增长。退化雄蕊、能育雄蕊、花柱在花形成后早期不融合,在后期才融合形成合蕊柱,且因为相对生长速率的不同,三者的相对位置、形态也发生改变。此外,在7~9月份引种至昆明栽培的不同批次杏黄兜兰中,产生花芽比率显著不同,进一步证实8月底至9月初是杏黄兜兰进行花器官形态分化的关键时期。 相似文献
136.
àngela Domínguez Núria Soldevila Diana Toledo Pere Godoy Jesús Castilla Lluís Force María Morales José María Mayoral Mikel Egurrola Sonia Tamames Vicente Martín Jenaro Astray Working Group of the Project PI/ 《PloS one》2016,11(1)
Vaccination of the elderly is an important factor in limiting the impact of influenza in the community. The aim of this study was to investigate the factors associated with influenza vaccination coverage in hospitalized patients aged ≥65 years hospitalized due to causes unrelated to influenza in Spain. We carried out a cross-sectional study. Bivariate analysis was performed comparing vaccinated and unvaccinated patients, taking in to account sociodemographic variables and medical risk conditions. Multivariate analysis was performed using multilevel regression models. We included 1038 patients: 602 (58%) had received the influenza vaccine in the 2013–14 season. Three or more general practitioner visits (OR = 1.61; 95% CI 1.19–2.18); influenza vaccination in any of the 3 previous seasons (OR = 13.57; 95% CI 9.45–19.48); and 23-valent pneumococcal polysaccharide vaccination (OR = 1.97; 95% CI 1.38–2.80) were associated with receiving the influenza vaccine. Vaccination coverage of hospitalized elderly people is low in Spain and some predisposing characteristics influence vaccination coverage. Healthcare workers should take these characteristics into account and be encouraged to proactively propose influenza vaccination to all patients aged ≥65 years. 相似文献
137.
目的:研究早期康复训练及监测患者自理能力对肝移植术后康复的影响。方法:选择2011年5月至2012年6月在我院接受肝移植手术的患者60例,按手术先后进行编号,使用随机排列表将患者分为实验组和对照组,每组各30例,对照组应用常规术后宣教和护理模式,室验组应用有针对性的"肝移植术后早期康复训练计划",并采用"自理能力监测表"对患者进行评估。分别比较两组患者的术后康复情况、睡眠和疼痛情况、术后第十日的自理能力以及术后早期并发症的发生。结果:两组患者康复情况比较,首次排气、排便、拔除尿管后首次排尿、首次下床和出院时间都有统计学差异(P0.05)。患者睡眠和疼痛情况比较,患者每日睡眠时间增加,安眠药物使用率明显减少(P0.05),而且术后康复训练没有增加患者术后疼痛的发生。术后第十日的自理能力比较,除自行进食(P0.05)外,自主上下床、自主如厕和自主洗漱三个方面室验组明显比对照组好(P0.05)。两组患者术后早期并发症的发生均无统计学差异(P0.05)。结论:早期康复训练和自理能力监测能有效促进肝移植术后患者的康复进程。 相似文献
138.
苏南地区稻田土壤肥力演变、养分平衡和合理施肥 总被引:12,自引:0,他引:12
采用宏观数据、研究参数与微观调查数据相结合的方法,分析区域肥力演变、养分平衡与合理施肥量。结果表明,1982-1996无锡市土壤氮素及有机质含量增加较快,磷素增加较慢,钾素含量普遍下降;1990-1997年无锡市和常州市稻田氮素普遍盈余,钾素普遍亏缺,磷素无锡市盈余,常州市亏缺;以此为依据,1996年无锡市氮磷钾肥的合理投入量分别是488.9、113.1和235.1kg·hm^-2;常州市分别为499.4、112.5和234.2kg·hm^-2,由于土壤中氮素积累、钾素亏缺现象明显,实际施氮量和施钾量要显著低于和显著高于合理施氮量和施钾量。 相似文献
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140.
九头狮子草化学成分的研究 总被引:3,自引:0,他引:3
从九头狮子草种分离得到9个化合物,分别鉴定为:正十八烷(1)、cholest-5-en-3β-oxyl hexadecanoate(2)、硬脂酸(3)、软脂酸(4)、三十三烷醇(5)、β-谷甾醇(6)β-谷甾醇和豆甾醇的混合物(7)、β-谷甾醇和豆甾醇的葡萄糖苷(8)、尿囊素(9).其中化合物1~5系首次从本植物中分得. 相似文献