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21.
Although the molluscicide Frescon is a strong neurotoxin to the Lymnaea stagnalis central nervous system in vitro, it is probable that the exposure of the whole animal to this molluscicide fails to result in central nervous system abnormalities: Frescon does not appear to reach the brain in sufficient quantity to disrupt its normal activity. However, only those Frescon analogs found to be neurotoxic were molluscicidal, suggesting some related mode, if not site, of action. Frescon and its analogs may act by affecting excitable tissues other than the nervous system (e.g., the snail musculature) by altering certain functional and/or structural membrane properties.  相似文献   
22.
从甜瓜子叶中提取总DNA   总被引:4,自引:1,他引:4  
陆璐  赵长增  陶兴林 《果树学报》2005,22(6):748-750
用分子标记方法检测甜瓜杂交种子纯度,如果从真叶中提取DNA,检测周期至少需要15d。为了缩短检测周期,我们分别以甜瓜的成熟干种子、吸胀水后“露白”种子、3d龄刚转绿子叶、6d龄子叶、9d龄子叶和12d龄子叶为材料,进行了提取总DNA的研究。结果表明:除了干种子和吸胀水后“露白”种子外,其他的材料都可以提取到DNA,但是DNA的质量因子叶日龄不同而存在很大的差异。不同日龄的子叶中,以3d龄子叶提取的DNA质量好。子叶6d龄时,提取的DNA质量次于3d龄,少量DNA开始出现降解,以后随着子叶日龄的增加,DNA降解加重。另外,与以真叶为材料提取的DNA样品相比较,子叶DNA样品中的蛋白质等杂质含量高,应增加氯仿抽提纯化次数。  相似文献   
23.
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   
24.
AIM:To explore the mechanism of neuronal injury and repair by investigating the expression of caspase-3 and apurinic/apyrimidinic endonuclease (APE/Ref-1) after focal cerebral ischemia. METHODS:A model of middle cerebral artery occlusion in rats was performed. The expression of caspase-3P20 and APE/Ref-1 was examined by immunohistochemistry staining, TUNEL was applied to detected DNA damage, and double labeling with TUNEL and APE/Ref-1 was used to determine the relationship between APE/Ref-1 and DNA damage. RESULTS:The active subunit P20 of caspase-3 was predominantly expressed within ischemic penumbra. The peak time of caspase-3P20 positive cells preceded the appearance of TUNEL. With aggravation of cerebral ischemia, APE/Ref-1 immunoreactive cells in penumbra were significantly decreased. CONCLUSION:The activation of caspase enzymatic cascade following cerebral ischemia leads to degradation in DNA, meanwhile, decrease in DNA repair molecules or the failure of DNA repair may deteriorate the course.  相似文献   
25.
梨自交不亲和强度不同品种花柱S糖蛋白含量的差异   总被引:12,自引:2,他引:12  
 提取梨( Pyrus) 自交不亲和强度不同品种花柱可溶性蛋白质, 应用等电聚焦电泳法在凝胶板上分离出S 糖蛋白, 用图像解析法进行定量。结果表明, 花柱总S 糖蛋白含量因品种而异, 自交不亲和强、弱及自交亲和的品种每1 􀀁g 花柱可溶性蛋白中含总S 糖蛋白分别为􀀂1. 3 ng 、0. 7 ~ 0. 9 ng、 0. 7 ng 。不同的S 基因所表达的S 糖蛋白量差异显著, 即使是同一S 基因所对应的S 糖蛋白量也因品种而异。  相似文献   
26.
The major role of DNA polymerase β was thought to be limited in its involvement in short patch base excision repair by removing 5’-deoxyribose phosphate and base insertion. However, the recent researches indicate that polymerase β might take part in a wide spectrum of DNA metabolism reactions, including long patch base excision repair, DNA replication, recombination, meiosis and transleisional DNA synthesis. Because of its wide and important cellular function, an inappropriate intracellular polymerase β level might be associated with genomic instability. Down-regulation or mutation of polymerase β is mutagenic due to deficient in DNA repair, while overexpression of this error-prone β polymerase might perturb the normal function of other accurate polymerases and cause genomic instability as well.  相似文献   
27.
AIM: To investigate the effects of platelet-derived growth factor on DNA and collagen protein synthesis in human vascular fibroblasts. METHODS: In the present experiment, the human vascular fibroblasts were cultured and effects of platelet-derived growth factor-BB on DNA and collagen protein synthesis in human vascular fibroblasts were observed by using [3H]-TdR incorporation and [3H]-proline incorporation in vitro. RESULTS: Platelet-derived growth factor-BB significantly promoted NDA synthesis and collagen protein synthesis of quiescent human vascular fibroblasts, with a maximal response at a concentration of 30μg·L-1at 24 h and 36 h, respectively. CONCLUSION: Platelet-derived growth factor-BB promotes DNA and collagen protein synthesis in cultured human vascular fibroblasts.  相似文献   
28.
AIM:To investigate the protein expression of cyclin D2 and p16 in proliferation and differentiation of cultured cardiac myocytes.METHODS:One-day-old Sparague-Dawley rats were used. Cardiac myocytes(CM) were collected by a trypsin-dispersal method and cultured. Cell growth line and fluorescence activated cell sorting (FACS) were used to investigate the proliferation of CM. Ultra-thin sections were made to observe the ultrastructure of CM under transmission electron microscope. The expression of cyclin D2 and p16 in CM were measured using immunocytochemistry and image analysis.RESULTS:①Results of cell growth line and FACS analysis showed that cultured CM could proliferate in the first 3 cultured days, but the ability decreased quickly, concomitant with differentiation. CM was obseved quiescent in cell cycle three days later. The ultrastructure of CM showed the large amount of myofilaments and mitochondrion. ②The protein expression of cyclin D2 in 3,4,5 day CM group was 0.89 times(P<0.05),0.80 times (P<0.05) and 0.56 times (P<0.01) of that in 1 day group, respectively. The expression of p16 in CM was increased during the culture process, 2,3,4,5 day group were 1.63 times, 1.72 times, 1.99 times and 2.84 times (P<0.01) of that in 1 day group, respectively.CONCLUSION:Cultured neonatal rat cardiac myocytes could proliferate during the first 3 days after incubation, but the ability of proliferation decreased, from the fourth day, concomitant with differentiation. Cyclin D2 and p16 play the key roles in CM postnatal development. Downregulation of cyclin D2 and upregulation of p16 may induce CM differentiation.  相似文献   
29.
两种复合肥在叶菜类蔬菜上的应用效果比较   总被引:1,自引:0,他引:1  
在山东省莱阳和寿光两地露地及保护地生长的芹菜和大白菜上进行新型复合肥 2 1 8 11S肥效研究 ,同时与市场上较为流行的 15 15 15S复合肥进行比较。结果表明 ,2 1 8 11S复合肥比 15 15 15S复合肥在增加产量、提高品质方面效果更好。 2 1 8 11S复合肥最佳用量大白菜为 14 14~ 170 0kg·hm-2 ,芹菜为 2 0 6 2~ 2 4 78kg·hm-2 。  相似文献   
30.
昆虫病原线虫rDNA多态性分析   总被引:1,自引:0,他引:1  
本文对国内外昆虫病原线虫斯氏属和异小杆属的47个品系进行rDNA—ITS PCR—RFLP分析,研究其DNA多态性,并构建了分子系统发育树状图。各品系的ITS区无明显的长度差异,PCR—RFLP分析将47个品系分为斯氏属和异小杆属两大类,两属线虫又分别分为11组和4组。所得结果丰富了ITS PCR—RFLP图谱库,为弄清我国的昆虫病原线虫与国外种类的分子系统发育关系及未定名线虫的鉴定提供重要依据,同时为筛选适合的线虫种类防治害虫奠定基础。  相似文献   
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