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91.
AIM:To investigate the effects of voltage-dependent K+ channel 1.5 (Kv1.5) on the proliferation and apoptosis of rat pulmonary artery smooth muscle cells (PASMCs) under hypoxia+hypercapnia condition and the relationship with mitogen-activated protein kinase(MAPK) signal pathway. METHODS:The PASMCs isolated from the male SD rat were cultured under hypoxia+hypercapnia condition, and randomly divided into normal group (N group), hypoxia+hypercapnia group (HH group), hypoxia+hypercapnia+DMSO incubation group (HD group), hypoxia+hypercapnia+U0126 (an extracellular signal-regulated kinase 1/2 inhibitor) incubation group (HU group), hypoxia+hypercapnia+SB203580 (a p38 mitogen-activated protein kinase inhibitor) incubation group (HS group), and hypoxia+hypercapnia+anisomycin (an agonist of MAPK) incubation group (HA group). Cell Counting Kit-8 was used to detect the cell viability. The protein expression of Kv1.5, PCNA and Bax was detected by Western blotting. RESULTS:Compared with N group, the cell viability and PCNA protein expression in HH group and HD group were significantly raised (P<001), but Kv1.5 and Bax proteins were significantly decreased (P<0.01). No difference between HH group and HD group was observed (P>005). Compared with HD group, the cell viability and PCNA protein expression in HU group, HS group and HA group were decreased (P<0.05 or P<0.01), but Kv1.5 protein and Bax protein were raised (P<0.01), with the most significant changes in HA group. CONCLUSION:The regulation of Kv1.5 to the proliferation and apoptosis of PASMCs under hypoxia+hypercapnia condition might have a relationship with the activation of MAPK signal pathway.  相似文献   
92.
施用不同钾肥对辣椒产量和品质的影响   总被引:1,自引:0,他引:1  
通过在辣椒上进行不同钾肥单独或混合施用试验,研究了不用种类钾肥对辣椒产量及品质的影响。研究结果表明,在正常施用氮、磷肥的基础上,处理1(全用K2SO4)产量最高,处理2(全用KCl)经济效益最高,杂椒线椒粗脂肪、VC含量均随K2SO4施用量上升而上升,太椒303随KCl施用量增加而增加,但产品中Cl^-含量是否超标有待进一步检测。  相似文献   
93.
Larvae of Haliotis discus hannai were induced to settle and metamorphose by exposure to seawater supplemented with bromomethane. The settlement and metamorphosis of veliger larvae were observed with bromomethane concentrations of 300, 600, 900, 1200, 1500 ppm on the benthic diatom plates. The highest settlement and metamorphosis rates of larvae were observed in bromomethane concentrations of 600 ppm.

Abalone larvae were induced to settle and metamorphose by exposure to seawater supplemented with potassium chloride. The settlement and metamorphosis of veliger larvae was observed in potassium chloride concentrations of 14, 19, 24 and 29 mM on the benthic diatom plates. The highest settlement and metamorphosis rates of larvae were observed in potassium chloride concentrations of 14–19 mM.  相似文献   

94.
林建忠 《安徽农业科学》2014,(22):7329-7331
“KClO3-longan model system”除了具有生产应用上的意义,更具有重要的科研潜力和科研价值.对氯酸钾促龙眼成花的植物生理学及分子生物学机理研究进行简介.  相似文献   
95.
钾、氯是烟草生长发育的必需营养元素,也是衡量烟叶内在品质的重要指标,钾氯比值常被用作评价烟叶品质、燃烧性的基础,因此合理调控烟叶钾、氯含量,对改善烟叶品质、提高烟叶质量、提升烟叶工业可用性具有重要意义。探讨了生态因素、栽培农艺措施对烟草钾、氯含量影响的研究进展。  相似文献   
96.
响应面法优化蚕沙叶绿素锌钾盐的制备工艺   总被引:1,自引:0,他引:1  
在单因素试验基础上,选取皂化时间、锌代温度和锌代时间作为影响因子,应用Box-Behnken中心组合设计建立数学模型,以叶绿素锌钾盐产率为响应值,进行响应面分析(RSA)。结果表明,叶绿素锌钾盐的最佳制备工艺为皂化时间58 min,锌代温度57℃,锌代时间83 min。响应面模型在此条件下预测的叶绿素锌钾盐产率为8.95%,验证值(9.23%)与预测值相对误差3.13%。  相似文献   
97.
通过钾素供应水平与甘蔗苗期基部混合组织、+3叶片、+5叶鞘含钾量以及蔗茎产量之间的关系研究表明:甘蔗幼嫩组织含钾量因土壤供钾水平不同而存在明显差异,株龄3~4月时,+3叶片全钾及+5叶鞘汁液水溶性钾含量与土壤速效钾供应水平有显著的相关性。在正常供水条件下(叶片水分含量>65%,叶鞘水分含量>80%),当苗期基部混合组织汁液水溶性K<1700×10-6,伸长期+3叶片全钾(干基)<1.35%、+5叶鞘汁液水溶性K<650×10-6时,提高钾素供应水平,蔗株组织含钾量和蔗茎产量都随之提高。这些组织含钾量能反映出钾素营养供应的丰缺状况。  相似文献   
98.
通过试验得出,春期桑园喷施磷酸二氢钾不仅可以提高桑叶产量和实力利用率,还可以改善桑叶叶质。较春叶摘芯起到更好的效果。本文还提出了该药剂的实用喷施方法。  相似文献   
99.
Twenty three non pregnant, non lactating aged Merino and Border Leicester ewes were subject to four jugular venipunctures one hour apart (times 0, 1, 2 and 3). Four different delay intervals of 12.5, 64.0, 128.0 and 252.9 seconds between catching and sampling (delays 1, 2, 3 and 4) were used on each sheep in a random manner. Estimates were made of packed cell volumes (PCVs), plasma and erythrocyte sodium and potassium concentrations. The mean PCV at time 0 of 35.4 per cent was significantly higher than the levels of 33.1, 31.8 and 32.2 per cent at times 1, 2 and 3 respectively. There was no significant difference between the means at times 1, 2 and 3. The mean plasma potassium concentrations at time 0 of 4.37 mmol/l was significantly higher than the levels of 4.16 and 4.14 mmol/l at times 1 and 3 respectively. Delays had no significant effects on the means of any of the parameters studied. The findings strongly suggest that sheep become excited by initial handling but not by subsequent venipunctures and that a delay between catching and sampling of between 12.5 and 252.9 second has no effect on the blood constituents studied.  相似文献   
100.
饲喂不同日粮的山羊尿沉渣晶体的化学组成和显微形态   总被引:2,自引:2,他引:0  
采集饲喂棉饼、玉米粉、麸皮、豆饼四种常见日粮的山羊尿样,应用化学定性分析、X-射线衍射物相分析、X-射线能谱分析和扫描电子显微镜观察等手段分别进行尿沉渣晶体的化学组成和显微形态的分析和观察。结果表明,饲喂棉饼日粮和麸皮日粮时山羊尿沉渣晶体的化学组成为磷酸钾镁,显微开矿为斜方柱状;饲喂玉米日粮时为碳酸镁,形态为长方柱状;饲喂豆饼日粮时为碳酸钙(方解石),形态为短方柱状。最后,还对几种尿沉渣晶体的生成  相似文献   
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