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41.
A spontaneously occurring rice (Oryza sativa L. ) mutant, characterized by homeotic conversion in glumes and stamens, was found in the progeny of a cross. The mutant showed long glumes and glumaceous lodicules and morphological transformation of stamens into pistils. Mutant florets consisted of 1 to 3 completely developed pistils, some pistilloid stamens with filaments, but tipped by bulged tissue and 0 to 3 stigmas. It seens that the mutant phenotype of the homeotic conversions in glumes and stamens is similar to that of the B loss-of-function mutants in Arabidopsis and Antirrhinum. The mutant is controlled by a single recessive gene as a segregation ratio of 3:1 (wild type to mutant plants) was observed in the F2 generation. 相似文献
42.
参考 Genbank收录的 TGEV- Miller株的基因序列 ,自行设计合成 1对引物 (TGEVP5 /P6 ) ,对不同代次的 TGEV疫苗弱毒 STC3及种毒 、种毒 进行了 RT- PCR扩增 ,产物经琼脂糖凝胶电泳分析 ,均出现 1条大约 12 6 2 bp的目的条带 ,经 Eco R 酶切 ,都产生了 871bp和391bp左右的两个片段 ,与预期大小相符。将种毒 RT- PCR扩增目的条带回收纯化后克隆入PMD18- T载体中 ,转化宿主菌 DH5 α,挑选阳性克隆 (命名为 PTs) ,提取重组质粒 ,用 Hpa 、Eco R 对重组质粒进行酶切鉴定以及 PCR扩增 ,然后进行序列测定 ,并进行了序列分析 ,证实与国外标准毒株 Miller、Fs772 / 70、Purdue、TO14等有较高的同源性 相似文献
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高寒牧区牧鸡鸭治蝗效果试验 总被引:3,自引:1,他引:3
在青海湖北岸高寒牧区利用人工饲养的鸡鸭进行放牧防治草原蝗虫。结果表明,在60d的防治期内,牧鸡鸭平均灭治效果达91.4%,为人工利用天敌治虫技术在高寒牧区的应用提供了依据。 相似文献
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将猪生殖与呼吸综合征病毒(PRRSV)的M基因和N基因从重组质粒pMD18-T—M—N中亚克隆至pBV220原核表达栽体上,成功构建了重组表达质粒pBVM—N。将pBVM—N转化大肠埃希氏菌DH5α感受态细胞.重组菌经温度敏感诱导表达,其细菌裂解物经SDS—PAGE可检测到分子质量约为19ku的目的蛋白,与M基因表达产物一致;经蛋白质分析软件Bandscan分析,其表达量可达19.1%;Western-blotting分析表明,该重组蛋白可被兔抗PRRSV血清所识别,与预期的M基因表达产物相一致,而N基因未获表达。 相似文献
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乌鲁木齐区域水资源利用中的生态经济问题及其调控对策 总被引:3,自引:0,他引:3
本文在考察乌鲁木齐区域水资源利用现状的基础上 ,从生态经济学的角度总结和分析了该区域水资源利用中存在的问题 ;针对问题 ,提出了相应的调控对策。 相似文献
49.
XU Rui ZHANG Yun ZHANG Mei GE Zhi-ming CHEN Wen-qiang LI Xiu-chang CAI Heng ZHU Hui 《园艺学报》2003,19(5):642-644
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
50.
AIM:To investigate the effects of fibronectin (FN) on the proliferation and collagen synthesis in cultured rat cardiac fibroblasts (CFb) derived from SHR (CFbSHR) and WKY (CFbWKY). METHODS:CFb derived from 12-week-old spontaneously hypertensive rat (SHR) and WKY was cultured by outgrowth of tissue block. Cell proliferation of CFb was measured by cell number counting and[3H]-TdR incorporation using 24-well plates pre-coated with 5 μg/cm2 of FN. Collagen synthesis was determined by [3H]-proline incorporation. RESULTS:As compared with control, the cell number of fibroblasts derived from SHR and WKY were significantly increased to 163.75% and 170.42% respectively after 72 h incubation with FN in the presence of 0.4% FCS from a intial cell density of 1×104 cells/mL. DNA synthesis of CFb was markedly promoted by FN. FN induced an increased in [3H]-proline incorporation in both CFbSHR and CFbWKY. CONCLUSION:FN is able to promote cell proliferation and collagen synthesis of CFb derived both from SHR and WKY. 相似文献