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21.
椰糠对黄瓜穴盘苗生长发育的影响   总被引:12,自引:0,他引:12  
将草炭、椰糠、蛭石按不同比例配制育苗基质,探讨椰糠对黄瓜秧苗生长发育的影响。结果表明,椰糠具有较好的保水性,酸碱度适合于作为穴盘育苗基质,出苗情况较好,秧苗质量高,证明椰糠是一种良好的园艺栽培基质。  相似文献   
22.
在不同提取方法下蜜蜂基因组DNA浓度的比较   总被引:7,自引:1,他引:7  
吉挺  陈晶  潘瑞 《中国蜂业》2005,56(12):10-11
本研究采用了国内外常见的5种蜜蜂基因组DNA抽提的方法,对意大利蜂工蜂基因组DNA进行提取,并进行了浓度检测.其中方法1,方法2采用的是5日龄的工蜂蛹体,而其他3种方法采用的是成年工蜂的头胸部进行提取.试验结果表明这5种方法之间差异极显著,其中方法2的浓度最高,为84.7850±24.5974,说明在相同实验条件下,方法2(蜜蜂蛹体一次抽提法)在浓度层次上效果最好.  相似文献   
23.
人为影响下古尔班通古特沙漠小尺度生态环境变化   总被引:1,自引:1,他引:1  
随着沙漠中油气资源勘探开发、公路建设和重大工程相继实施 ,对生态环境的人为影响日益加深。本文以重大工程实验点为例 ,通过研究对比工程影响区内人工沙垄和自然沙垄的砂质新成土理化性状和植被群落特征 ,指出了沙漠生态环境在人为干扰下发生的一系列变化 ,以及受损生态环境在人们采取积极补救措施的情况下所具有的自然修复能力  相似文献   
24.
AIM:To elucidate the relationship between the intracellular calcium concentration changes and left ventricular hypertrophy and function in the spontaneously hypertensive rats (SHR).METHODS:Intracellular free calcium concentrations were measured by Fura 2 methodology and left ventricular function quantitated by cardiac catheterization in 20 SHR aged 10, 22, and 34 weeks and 20 age-matched Wistar-kyoto (WKY) rats.RESULTS:(1) The systolic blood pressure(SBP), intracellular calcium concentrations and left ventricular mass / body weight index (LVM/BW) were significantly higher in all three age groups of SHR than the corresponding groups of WKY; (2) Compared with age-matched WKY groups, the peak left ventricular pressure descending rate(-dp/dtmax) decreased while left ventricular relaxation time constant (τ)increased significantly in SHR aged 22 and 34 weeks. The peak left ventricular pressure ascending rate(dp/dtmax) and the left ventricular contractility index were significantly increased only in the 34 weeks SHR; (3) Intracellular calcium concentrations showed a positive correlation with LVM/BW,SBP,-dp/dtmax and τ(r=0.47-0.83,P<0.01)and a negative correlation with dp/dtmax and the left ventricular contractility index (r=-0.46,P<0.05 and r=-0.81, P<0.01).CONCLUSION:Intracellular calcium overload is one of the potential mechanisms in the induction of left ventricular hypertrophy as well as of systolic and diastolic dysfunction.  相似文献   
25.
AIM:To investigate the effects of FK506 on anti-glomerular basement membrane(GBM) nephritis in rats. METHODS: Anti-GBM nephritis model was elaborated by rabbit anti-rat GBM antibody injection in SD rats in this study. The rats were divided into three groups: FK506 treated group(0.5 mg·kg-1·d-1, sc), untreated nephritis control group and normal control group. FK506 was administered daily six hours after injection of anti-GBM IgG. All the rats were observed urinary protein at the 4th day, the 14th day and the 21st day. At the same time, the kidney specimens were collected, and T cell transforming function was also monitored.RESULTS:Rats injected with rabbit anti-GBM Ab developed heavy proteinuria by 4 days, and serum creatinine and serum urea appeared which kept on the rising. Glmerular hypercellularity, crescents, and protein casts were observed in nephritic rats. By electron microscopy, the thickening of GBM and loss of foot processes were seen. T cell transforming function was higher than normal. But, all pathological changes obviously turned for the better in FK506 treated group. CONCLUSION:FK506 could inhibit the progression of rat anti-GBM nephritis.  相似文献   
26.
一种监测棉铃虫对Bt杀虫晶体蛋白抗性的技术   总被引:1,自引:0,他引:1  
研究了以诊断试剂盒监测棉铃虫对苏云金杆菌(Bt)杀虫晶体蛋白(ICP)抗性的技术。将1日龄幼虫在含诊断剂量的饲料中(每毫升饲料含Bt ICP0.01mg)取食7天,以生长至3龄以上的个体作为抗性个体的判断指标;筛选出人工饲料中防腐剂剂量的最佳值为每350毫升饲料中含丙酸2.5ml。经对多个棉铃虫不同抗性种群的验证试验,证明诊断试剂盒检测抗性个体频率较为精确且应用简便。  相似文献   
27.
AIM:To determine the effects of Angiotensin II(AngII) on migration of rat smooth muscle cells and to investigate the mechanisms underlying Ang II action in the development of injured vascular disease. METHODS:VSMCs isolated from aortic media of Wistar rats and cultured by the modified explant method were adopted. In prersence and absence of AngII, the expression of AngII receptor and reorganization of the actin cytoskeleton of VSMCs were studied by immunocytochemistry technique, fluorocytochemistry technique. The migration assays were performed by a modified Boyden's chamber. And the effects of AT1R antagonist (CV-11974), AT2R antagonist (PD123319) on aforementioned target were studied.RESULTS:VSMCs migration was stimulated by addition of AngII. The dynamic reorganization of actin cytoskeleton may be an important mechanism by which AngII facilitates VSMC motility. The expression of AT1R in VSMCs can be upregulated after treatment with AngII initially, then decreased gradually. The expression of AT1R was downregulated by AT1R antagonist. The effect of AngII on VSMCs migration was mediated by AT1R, while AT2R had no significant effect.CONCLUSION:The dynamic reorganization of actin cytoskeleton is required for AngII-induced VSMC migration, and this effect is mediated by AT1R .  相似文献   
28.
 ‘坠玉’醋栗品种是从美国引进品种中筛选出的优良品种。该品种果实大, 品质好, 果梗较长, 采摘容易, 生长势强, 抗白粉病能力强, 对醋栗叶斑病感病极轻, 丰产稳产, 可在东北地区推广。  相似文献   
29.
双孢蘑菇子实体多糖的提取及单糖组成   总被引:6,自引:0,他引:6  
从双孢蘑菇(Agarigus bisporus)子实体中提取多糖,提取率为0.65%,DEAE-Cewllulose-52柱层柱纯化了多糖,聚丙烯酰胺凝胶电泳显示一条带,为蛋白结合多糖,多糖水解液纸层析结果表明,多糖由D-果糖和D-葡萄糖构成。  相似文献   
30.
Nitric oxide (NO) and matrix metalloproteinases (MMPs) are important in vascular remolding, especially in abdominal aortic aneurysm. NO may be associated with aneurysms by modulating MMPs expression and activity.  相似文献   
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