几种重金属离子及类金属砷对烟草组织培养的影响

本文以烟草为材料，在培养基中添加不同浓度的三种重金属离子(Hg^2-、Pb^2 、Ag^ )及类金属离子砷(As^5 )，经组织培养，发现经处理的烟草生长发育均受到不同程度的抑制．而且叶绿素和可溶性糖含量均比对照降低，仅蛋白质含量在金属及类金属离子浓度低(5ppm、10ppm)时部分升高．其余均降低，当这些重金属及类金属离子在培养基中的难度达到500ppm以上时，烟草的生长发育全被抑制。     

大气CO2浓度升高对全球CH4排放的影响

论述了全球变化中2个重要温室气体CO     

Cardiac protective role of a novel erythrocyte-derived depressing factor on rats and its Ca^2＋ mechanism

The cardiac protective role of a novel erythro-cyte-derived depressing factor (EDDF) on spontaneous hy-pertensive rats (SHR), calcium overload (CaO) rats and Wistar rats and its mechanism was evaluated. Mean artery pressure (MAP), heart rate (HR) and LVdp/dtmax were measured by physiological recorder. The effect of EDDF on the Ca2+-ATPase activity in myocardial sarcoplasmic reticu-lum (SR) of CaO rats was determined by inorganic phos-phate assay. Calcium transport in myocytes was measured by 45Ca2+ radioactive isotope measurement. The phosphoryla-tion levels of extracellular signal-regulated protein kinases (ERK1/2) in myocardial tissue of SHR and CaO rats were measured by Western blot method. And the ultrastructures of cardiac muscle cells were observed with the transmission electron microscope. The results indicated that EDDF could significantly decrease MAP, HR and LVdp/dtmax in a dose dependent manner (P < 0.05). It seems that the mechanism might relate with activating the Ca2+-APTase, enhancing the uptake and release of Ca2+ from SR (P < 0.05), decreasing the phosphorylation levels of ERK1/2 of myocytes (P < 0.01) and lightening the ultrastructural lesion of cardiac muscle cells. In CaO rats, the Ca2+-ATPase activity decreased clearly com-pared to control (64.99 7.16 vs 94.48 7.68 nmol·min-1 ·mg-1 protein, P < 0.01), while EDDF (100 mg/mL) could significantly increase the activity (87.93 ?9.54 vs 64.99 ?7.16, P < 0.05, n = 7). Both uptake and release rate of Ca2+ (祄ol 45Ca2+/g protein/min) from myocardial SR of CaO rats re-markably decreased compared to control (32.40 ?2.70 and 15.46 ?1.49 vs 61.09 ?10.89 and 25.47 ?4.29, P < 0.05); EDDF (100 mg/mL) could significantly stimulate their activi-ties (50.48 6.76 and 21.76 2.75 vs 32.40 2.70 and 15.46 1.49, P < 0.05). EDDF could evidently down-regulate the phosphorylation of ERK1/2 in myocardial tissue from SHR and CaO rats (P < 0.01), lighten the ultrastructural lesion of cardiac muscle cells of SHR as well. It is concluded that EDDF seems to play protective roles on both structure and function of heart, which closely related with amelioration of Ca2+ transport and inhibition of Ca2+-MAP kinase pathway.     

问：除了使冰川加速融化、海平面升高外，全球变暖的影响还有哪些？

全球变暖的影响远不止冰川融化和海平面升高，全球变暖甚至可以使地球面临物种大灭绝的威胁。     

温度对激光场引起的纳米管声子增益影响

讨论了强激光场下单壁纳米管的声子增益效应. 采用含时微扰方法计算了不同温度下声子占据数随时间的变化率(声子增益系数). 计算结果表明,在强激光场下纳米管中的声子占据数随时间非线性增加,增益系数与温度和激光场强都有关系. 随着温度升高,声子增益系数迅速减小;在确定的温度情况下,激光场强越强,声子增益效应越明显,并对这个现象给出了合理的物理解释.     

浅谈低压电网中零线电位升高的原因及改善措施

本文主要探讨了低压电网中零线电位升高的原因及改善措施，升高原因有：电压在零线阻抗上引起的电压降，零线断线及零线接地不良，改善措施有：零线应妥善接地，设备外壳接零也必需接地，三相负葆尽量平衡，零线截面不能太小等。     

老年血压变异参数正常参照值研究

本文报告50例非高血压病老年人长时血压变异参数正常参照值上限（95％可信限）为一步研究老年人血压变异与心脑血疾病的关系及中远期预防措施提供基础依据。     

巧治柴油溅进蓄电池

先擦净蓄电池上的油污，再打开瓶盖，擦净盖口，然后加蒸馏水至离上口边2-3毫米处。在保证蓄电池温度低于50℃并远离明火的条件下，按每单格5-10安培的电流充电。开始时电流可大一点，当电液冒泡后应减小充电电流。随着充电时间的增加，电液、极板体积随温度升高而逐渐膨胀，电液液面随之升高，漂浮在电液表层的柴油，便从瓶口溢出。     

猪乙型脑炎的防治

症状 生猪常突然发病，体温升高至40～41℃，呈稽留热，持续几天至十几天。病猪精神委顿，嗜眠喜卧，食欲减少，口渴，眼结膜充血潮红，粪便干燥呈球形，表面常附有灰黄色或灰白色的粘液，尿呈深黄色。有的病猪后肢呈轻度麻痹，步态蹒跚，关节肿大：有的病猪精神兴奋，出现神经症状，横冲乱撞。妊娠母猪患病时，主要表现为流产或早产，胎儿多是死胎、木乃伊胎或是大小不等，