Alterations of G-protein Coupling Function in Phosphoinositide Signalling Pathways of Rat Hippocampus by Ischaemic Brain Injury

The activation of membrane-associated phospholipase C is rapidly and transiently induced in the central nervous system by a variety of stimuli. Ischaemic brain injury is one of the situations that leads to a dramatic increase in polyphosphoinositide (PPI) turnover. In this study, stimulation of PPI hydrolysis by glutamate (500 μM) was measured in hippocampal slices from rats up to 21 days after an ischaemic insult of 30 min. Ischaemia was induced using the four-vessel occlusion method. PPI hydrolysis elicited by glutamate was significantly increased in the slices prepared from ischaemic rats 24 h after reperfusion, the accumulation of inositol phosphates (InsP_s) and inositol 1,4,5-trisphosphate (InsP₃) was 614±74% ( n = 8) and 182±11% ( n = 9) of the basal level respectively. This potentiation was also observed 21 days after ischaemia. Hyper-responsiveness to glutamate was also accompanied by an increase in AIF⁻₄-stimulated formation of [³H]inositol phosphates. In addition, global ischaemia did not change either high-affinity [³H]glutamate binding in hippocampal membranes or the stimulation of PPI hydrolysis by carbachol or noradrenaline in hippocampal slices. The present results suggest that the increased responsiveness to glutamate is the result, at least in part, of functional changes at the G-protein level, and may contribute to the pathophysiology of ischaemic brain injury or to the regenerative phenomena that accompany ischaemic damage.     

我国青年男子理想体重计算方法的探讨

在营养调查的基础上,以975名北方籍和921名南方籍青年为代表,以实测身高体重为依据,分别推出了理想体重计算公式。北方理想体重(kg)=[身高(cm)-150]×0.6+50;南方理想体重(kg)=[身高(cm)-150]×0.6+48。为检验样本的代表性,又另取北方籍783名青年和南方籍883名青年进行了验证,结果表明,推出的计算公式有较好的代表性。用推出的计算公式分别对1464名北方青年和2264名南方青年的身高体重进行分析,结果表明,新推出的计算公式比以往的计算公式更符合我国的情况,因而更具有实用意义。     

蛛网膜下腔注射神经降压素对大鼠血压和心率的影响

本文研究了蛛网膜下腔注射神经降压素（ｎｅｕｒｏｔｅｎｓｉｎ，ＮＴ）对大鼠血压和心率的影响，结果表明：注射ＮＴ后血压立即下降，继而有所回升，但不及正常水平，然后再次降低，持续６０ｍｉｎ；心率无明显改变。Ｈ１受体阻断剂苯海拉明能部分阻断ＮＴ的降血压效应，Ｈ２受体阻断剂甲氰咪胍无翻转作用。注射组胺释放剂Ｃｏｍｐｏｕｎｄ４８／８０使血压下降，待血压恢复正常水平后，再注射ＮＴ，其降压效应减弱。结果提示：蛛网     

橡胶活性官能团对增韧环氧树脂动态力学性能的影响

用动态扭摆法测试聚丙烯酸丁酯橡胶增韧环氧树脂的动态力学行为,研究在环氧树脂低固化度和高固化度时,橡胶活性官能团种类(环氧基官能团与羧基官能团)和数量(官能度)对其影响。研究体系中橡胶玻璃化转变温度(Tg)的移动大小,与橡胶和基体树脂健合程度之间的关系。     

广东78种食物的不溶性膳食纤维含量分析

本文采用中性洗涤剂法测定了广东78种食物的不溶性膳食纤维含量,结果提示,不溶性膳食纤维的平均含量:干豆坚果类为7.12％,鲜果类为1.93％,根茎类为1.55％,叶菜类为1.31％,粮谷类为1.27％,茄瓜类为1.15％。其中干豆坚果类与茄瓜类、粮谷类、叶菜类、根茎类和鲜果类的含量差别极显著(P<0.01),而后五类食物的含量相互间差别不显著(P>0.05)。粮谷类的变异系数较大(CV:142％)。其中以加工较深的米面及其制品较低(0.31％—0.72％),而未深加工的玉米、薏米的含量则高(2.48％—6.08％)。