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61.
西瓜核型雄性不育两用系POD同工酶研究   总被引:1,自引:1,他引:1  
用PAGE(聚丙烯酰胺凝胶)电泳技术,研究了西瓜核型雄性不育两用系不同器官的POD(过氧化物酶)同工酶酶谱差异。试验结果表明,不育株与可育株主要差异在雄花蕾,表现为不育株较可育株多2条活性强的酶带;其他器官差异小,仅表现为酶谱带强弱不同。并对POD同工酶与雄性不育性的相关性进行了研究。  相似文献   
62.
在室内人工模拟干旱条件,测定了干旱胁迫下披碱草和野大麦及其杂种幼苗的相对含水量、细胞膜透性、游离脯氨酸含量的变化。结果表明,干旱胁迫下亲本披碱草幼苗的组织相对含水量下降的幅度最低,细胞膜受害最轻,游离脯氨酸积累的最多,相对生长率最高,表现出很强的抗旱性。亲本野大麦幼苗的组织相对含水量下降的幅度最大,细胞膜受害最重,游离脯氨酸积累的最少,相对生长率最低,抗旱性弱。杂种F1幼苗的保水能力、细胞膜受害程度和游离脯氨酸积累能力、相对生长率均介于双亲之间,亦即其抗旱能力大于野大麦而小于披碱草,表现为双亲的中间型。正、反交对杂种F1的抗旱能力没有明显影响。  相似文献   
63.
乌梁素海湿地环境与资源地理信息系统的研究   总被引:6,自引:0,他引:6  
本系统建立乌梁素海湿地基础地形库、生态库、资源库、工程档案库、遥感影像库等基础数据库及信息发布系统 ,使 GPS、GIS、RS紧密结合 ,同时实现了专家决策支持系统与地理信息系统之间的一体化集成。本系统可以为乌梁素海湿地生态治理与资源开发提供全方位的数据信息及其管理 ,对生态工程规划与实施方案进行优化设计 ,并提供实时监控服务。  相似文献   
64.
FEI Jia  ZHANG Huan 《园艺学报》2003,19(5):645-648
AIM:The effective antisense sequences targeted VEGF mRNA with computer software would be screened and designed, and effect of them on growth K562 cells and protein expression of VEGF were studied with experiments.METHODS:Seven antisense sequences were selected and synthesized, which consisted of 18-20 deoxynucleotide acid and were modified with phosphorothioate, according to principle of low free energy of overall △G37 Overall. Cell growth was assayed by trypan blue dye exclusion assay and level of VEGF protien in the media was determined by ELISA.RESULTS:Six of seven sequences were capable of inhibing growth of K562 cells and downregulating the VEGF protein expression significantly, compared with Scrambed control group. It was found that there was a close correlation between low level of overall △G37 and antisense effectiveness (r=0.887,P<0.01).CONCLUSION:VEGF mRNA antisense oliogdeoxynucleotides, which were designed by computer software of RNAstructure, were able to inhibit growth of K562 and its protein expression. The VEGF mRNA may be new target attached by drugs. At same time, the computer aided design is useful methods to obtain the effective antisense.  相似文献   
65.
FAN Ying  WANG Jia-hui  FU Qi  MA Ji 《园艺学报》2003,19(6):859-861
The onset of idiopathic thrombocytopenic purpura (ITP) is related to excessive destruction of platelet resulting from antiplatelet autoantibody. The immunity with ITP is imbalance, so the hypofunction of suppressor T cell (Ts) can't restrain B lymphocytes producing antibody, as a result, autoant ibody is produced, the clearance of platelet in blood circulation is accelerated. The different antibodies have different functions on ITP. The measuring of platelet antibody has its significance in diagnosis, therapeutic evaluat ion and expectation of prognosis.  相似文献   
66.
以地处河西走廊的张掖、临泽、高台和酒泉等县 /市级行政区为景观单元 ,利用LandsetTM影像资料的目视解译 ,在ArcView 3.1和景观格局分析软件FRAGSTATS的支持下 ,计算各绿洲景观格局指标。结果表明 :荒漠类型在四个绿洲景观组分中占绝对优势 ,其次为水浇地 ,但不同绿洲水浇地所占比例相差较大 ,酒泉最高 ,张掖其次 ,高台最低 ;斑块数、斑块密度、边缘密度和平均斑块面积的差异表明 ,张掖绿洲景观类型最多且斑块粒径小 ,而高台则完全相反 ,体现出单调而粒径粗大的荒漠绿洲特征。  相似文献   
67.
AIM:To investigate whether the bcl-2 antisense oligonucleotide increases the sensitivity of HL60 and K562 cell lines to daunorubicin.METHODS:IC50 for HL60 and K562 was determined with MTT method, the expression levels of Bcl-2 protein were assayed by immunofluorescence using fluoresce isothiocyanate labeling. In addition, apoptosis was detected by morphological observation and flow cytometric analysis of DNA fragmentation.RESULTS:It was found that the two oligonucleotides directed against the coding region and the translation initiation of bcl-2 mRNA, combined respectively with daunorubicin, inhibited expression of bcl-2 protein, increased apoptosis in HL60 and K562 cells, and decreased IC50 of daunorubicin significantly (P<0.05). Compared to the antisense oligonucleotide directed against the translation initiation of bcl-2 mRNA, the antisense oligonucleotide directed against the coding region showed stronger effects in the aspects of increasing the sensitivity of HL60 cells to daunorubicin (P<0.05).CONCLUSIONS:These two antisense sequences in the translation initiation and the coding region of bcl-2 mRNA increased the sensitivity of HL60 and K562 cell lines to daunorubicin in a sequence-specific manner.  相似文献   
68.
69.
AIM:To explore the serum levels of certain adhesion molecules and its significance in acute coronary syndrome(ACS). METHODS:The subjects included 40 patients with acute myocardial infarction(AMI) and 40 patients with unstable angina pectoris (UAP). Among the 80 patients, 60 patients accepted a follow-up 4 months. At the same time we selected 40 controls from people who attended a routine health check in the university. Serum levels of E-selectin, sICAM-1, sVCAM-1 were measured by ELISA.RESULTS:Serum levels of E-selectin, sICAM-1, sVCAM-1 were significantly higher in the ACS group(AMI or UAP) than in the control group. Four months later, the levels of E-selectin, sICAM-1 became significantly lower in the follow-up group than in the ACS group, while sVCAM-1 showed no significant difference. CONCLUSION:Serum levels of E-selectin, sICAM-1 may have certain diagnostic value for ACS, and can be a useful marker reflecting the stability of the disease.  相似文献   
70.
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