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91.
MA Ying-chun ZHENG Meng-xiao HUANG Lin-jing WANG Yuan-yuan YING Lei WANG Wan-tie 《园艺学报》2014,30(9):1645-1650
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<001), but Kv1.5 and Bax proteins were significantly decreased (P<0.01). No difference between HH group and HD group was observed (P>005). 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
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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.
“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
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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.
Fenwick D. C. Blackshaw Judith K. Green Deborah J. 《Veterinary research communications》1986,10(1):309-315
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