铜、镉对鲫鱼组织Na+-K+-ATPase酶活性的影响

在实验条件下研究了铜、镉中毒鲫鱼组织Na^ -K^ -ATPase酶活性的变化，结果表明，受水中Cu^2 ,Cd^2 的影响，Na^ -K^ -ATPase酶活性呈下降趋势，当水中Cu^2 浓度为2、4mg/L时，脑，肝胰脏和鳃的酶活性显著降低，在4mg/L浓度时肾脏的酶活性显著降低；当水中Cd^2 浓度为1、2mg/L时，酶活性均显著下降，在肝胰脏，肾脏下降最为明显。     

细胞外钙离子对人成骨样细胞 MG-63分化的影响

研究不同浓度钙离子对人成骨样细胞MG-63分化的影响.结果表明, 5.0mmol/L Ca2+促进 CaSR、ALP、OC、Runx 2、IGF-1和BMP2 mRNA表达,而加入CaSR和ERK抑制剂后,则下调 ALP、OC、Runx 2、IGF-1和BMP2 mRNA表达.不同浓度Ca2+处理后,磷酸化-ERK(p-ERK)蛋白表达明显增加.因此,5.0mmol/L Ca2+通过上调CaSR基因的表达,激活ERK通路,促进MG-63成骨样细胞的分化.     

铜对不同水稻品种种子萌发及根尖分生细胞钙分布的影响

以16个水稻品种为材料,测定了铜对水稻种子萌发相关指标,并观察了根尖有丝分裂及分生区Ca分布的影响。结果表明：（1）0．1mM和0．2mMCuSO4溶液处理对水稻根长的抑制作用大于对芽长的抑制,且对不同品种根长的抑制作用存在明显差异;（2）随着铜处理浓度（25、50、75、100μM）的升高,根尖细胞有丝分裂指数及相对有丝分裂指数皆呈下降趋势;（3）t常生长条件下,水稻根尖分生区细胞中的Ca主要分布在液泡和细胞间隙中,而细胞质、细胞核中分布很少;50μM铜处理下,根尖分生区细胞液泡和胞间的Ca沉淀颗粒明显减少,而胞质及核基质中的Ca沉淀颗粒增多。铜胁迫造成根尖细胞中原有Ca分布的变化可能是引起细胞功能的紊乱,进而影响根系生长的原因之一。     

Caprine cardiac sarcoplasmic reticulum: Effect of simulated ischemia on membrane structure and Ca<Superscript>2+</Superscript>-ATPase activity

The sarcoplasmic reticulum was isolated and characterized in the pure form from normal caprine (Capra hircus) hearts. Under ischemic condition, fatty acids like palmitic acid, palmitoyl carnitine and oleic acid accumulatein vivo. These are known to have a detrimental effect on membrane components. The effects of simulated ischemia on the Ca²⁺-ATPase were studied using these fatty acidsin vitro at concentrations at which they occurin vivo in the ischemic heart. All three fatty acids inhibited Ca²⁺-ATPase activity. At lower concentrations, palmitoyl carnitine was the most potent, followed by oleic acid while palmitic acid displayed the least potency. Electron microscopy studies with fatty acids showed morphological disruptions in SR vesicles. The decline in Ca²⁺-ATPase activity could be attributed to the change in membrane morphology.     

利用H2O-NaCl-CaCl2体系水盐化合物和冰的融化温度计算NaCl/（NaCl＋CaCl2）比值和盐度的方程

The composition of fluid inclusions in the H2O-NaCl-CaCl2 system has been generally graphically estimated using the melting temperatures of hydrohalite （ Tm-HH ） and ice （ Tm-ice）. Here we present two equations that can be used to calculate the relative proportion of NaCl （ i. e. , NaCL/[ NaCl ＋ CaC12 ] , or XNacl ） and the total salinity （ i. e. , NaCl ＋ CaCl2, wt% ） for fluid inclusions with ice as the last melting phase. XNacl can be calculated from Tm-HH using the following equation： y = （a＋bx）^-1/c where y is XNacl, x is Tm_HH , a =0. 33124402, b =-0. 031518028, and c =0. 22932736. In the cases where only Tm-ice is measured and Tm-HH is not known, Tm-ice can be used as the maximum possible Tm-HH to calculate the maximum value of XNacl using the above equation. In these cases, the following equation can be used to calculate the maximum total salinity： y=（a＋bx＋cx2） l where y is salinity, x is Tm-HH , a =0, 057184817, b =0. 00078565757, and c = 5. 7262766E-6. Because the isothems in the field of ice are sub-parallel to the NaCl-CaCl2 binary side in the H2O-NaCl-CaCl2 ternary system, the errors in salinity calculation introduced by the above approximation are small （ less than 2 wt% ）. A Windows program for calculation of XNacl and salinity is available at ： http ：//uregina. ca/-chiguox.     

Effect of corticosteroids on elevated intracellular sodium, plasma lipid peroxide levels and reduced Na+, K+-ATPase activity in patients of bronchial asthma

In view of several reports that there is a lack of balance in free radicals in case of bronchial asthma (1) the effect of free radicals on cell membrane was studied by estimating the membrane bound protein Na⁺, K⁺-ATPase activity and the intracellular sodium level in patients of bronchial asthma before and after a short course (one week) of oral corticosteroid (prednisolone 0.75–1mg/kg body weight) therapy. Results showed that there is a definite statistically significant rise in free radical level and intracellular sodium level and a significant lowering of Na⁺, K⁺-ATPase activity in case of untreated bronchial asthma. After short course of therapy with oral corticosteroids, the free radical level and intracellular sodium level decreased significantly, together with a significant rise of the Na⁺, K⁺-ATPase activity. Also, a significant negative correlation (r=−0.74) between the lipid peroxide level and the Na⁺,-K⁺-ATPase activity was found in these cases.     

转轨经济时期政府在R&D活动中的职能与定位研究

在研究转轨经济时期我国政府在R&D活动中职能与定位必要性的基础上,探讨转轨经济时期R&D活动的特殊性,分析美、芬、日、韩四国政府在R&D活动中的角色及职能作用,并结合转轨经济时期的特殊国情对我国政府在R&D活动中的职能和定位进行研究,为各级政府制定R&D活动的政策和正确发挥政府职能提供参考.     

Anticancer Effect of dl-Glyceraldehyde and 2-Deoxyglucose in Ehrlich Ascites Carcinoma Bearing Mice and Their Effect on Liver,Kidney and Haematological Parameters

Cancer cells generally exhibit increased glycolysis for ATP generation (the Warburg effect). Compounds that inhibit glycolysis have potential applications in cancer treatment. dl-glyceraldehyde (DLG) and 2-Deoxyglucose (2-DG) have been proven effective in the inhibition of glucose metabolism. Ehrlich ascites carcinoma (EAC) cells were injected intraperitoneally (i.p) in 10–12 weeks old Swiss albino mice, weighing between 20 and 30 g. The anticancer activity of DLG and 2-DG were determined by tumor volume, tumor weight, viable and nonviable tumor cell count, average survival time, percentage increase in life span and tumor inhibition ratio. The blood samples were obtained for biochemical analysis after 9 days of treatment to study the effect on liver, kidney and haematological parameters. Histopathological examination of liver and kidney was also performed. One-way ANOVA test and Dunnett’s test were used for comparisons of parameters in study groups. Both DLG and 2-DG individually decreased the tumor weight, tumor volume, viable tumor cell count and significantly increased the life span of treated mice, however the combination was found to be better. The biochemical parameters of liver and kidney functions and haematological parameters were restored close to control group as compared with the EAC bearing mice. Histopathological examination of liver and kidney in EAC control group showed large areas of necrosis, congestion and mononuclear cell infiltration but such changes were not observed in liver and kidney sections observed after i.p injection of DLG and 2-DG for 9 days. Improvement was much better in the group where combination of these two drugs were used.     

中国经济空间格局演变及其CO2排放效应

改革开放以来,中国经历了由东部率先发展到区域协调发展的区域战略调整,中国经济空间格局发生较大改变.探究CO2排放量对经济空间格局演变的响应,对中国尽早实现CO2排放达峰目标、确保可持续发展具有重要意义.本文在刻画1985-2017年中国经济空间格局演变特征的基础上,基于LMDI因素分解方法分析了中国CO2排放的驱动因素...