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Mechanical stress was one of stresses with whichplants often met. With the development of fruit andvegetable finish machining in food industry, artificialinjury also appeared. As response to other stresses,plants have evolved with some adaptive mechanismsto cope with wounding[1]. Jasmonic acid (JA) andmethyl jasmonate (MeJA), as important signal mole-cules in plant response to wounding, have attracted agreat deal of attention. The studies on some crops, suchas potato[2], rice[3], and tomato[…  相似文献   
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采用简单随机抽样法对柴达木山羊群体进行了遗传检测,从毛色、外型特征、体尺、血液蛋白与DNA多态性等5个方面进行了群体遗传结构分析,并探索了其系统地位。结果表明:(1)毛色和形态特征的平均表型异质度分别为0.3419、0.5207;(2)血液蛋白在6个基因座上具有多态性,平均基因座杂合度为0.2584;(3)DNA-RAPD标记表现丰富的多样性,基因多样度为0.4085~0.5318。通过对柴达木山羊与其他国内山羊的系统聚类,初步探索了该山羊群体的形成及所属,这些都表明柴达木山羊是一个比较古老的未经较高强度选育的地方山羊品种,其基因资源是我国山羊遗传资源中宝贵的一部分。Abstract: Genetic structure and character of Chaidamu Goats were studied through simple random sampling. Genetic structure was analysed from five aspects, and phylogeny status was also investigated. The results indicated that: (1) the average phenotypic heterogeneity degree of coat color and morphological character were 0.3419 and 0.5207,respectively; (2) polymorphous blood albumen existed in 6 loci and the average loci heterozygosity was 0.2584; and (3) polymorphism existed in marked genes by DND-RAPD with diversity of 0.4085~0.5318. Phylogeny status was investigated through clustering by Ward’s method on Chaidamu Goats and other domestic goats. All these indicated that Chaidamu Goats was a domestic goat with less intensively selected breed.  相似文献   
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目的探讨弱酸(盐)对植物乳杆菌耐酸性的影响。方法在植物乳杆菌发酵过程中,添加50mmol/L乙酸、10mmol/L丙酸、20mmol/L正丁酸、50mmol/L乙酸钾及2mmol/L柠檬酸钾。结果添加剂量均可使植物乳杆菌耐酸性得到较大的提高,在pH2、37℃下90min,细胞残存率都较对照提高80倍以上,尤以乙酸(盐)、正丁酸为好,而三聚磷酸钾则对细胞耐酸性提高具有较小的作用,细胞残存率较对照约提高5倍。结论在发酵培养基中添加弱酸(乙酸、丙酸及正丁酸)或弱酸盐(乙酸钾、柠檬酸钾及三聚磷酸钾)均可不同程度地提高植物乳扦菌细胞耐酸性。  相似文献   
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发现9种新的人类染色体异常核型,分别为: 46, XX, t(2; 10)(q33; q11); 46, XY, t(10; 12)(q26; q22); 46, XY, t(6; 15)(p23; q23); 46, XY, t(1; 6)(p36; q21); 46, XY, t(1; 19)(p32; p13); 46, XY, t(16; 18)(q22; q21); 46, XY, inv(1)(p36q25); 46, XY, t(13; 17)(q12; q25); 46, XY, t(15; 21)(q26; q11)。异常核型是导致自然流产和不育的原因。 Abstract Nine new kinds of human chromosomal abnormal karyotypes were reported. They were46, XX, t(2; 10)(q33; q11); 46, XY, t(10; 12)(q26; q22); 46, XY, t(6; 15)(p23; q23); 46, XY, t(1; 6)(p36; q21); 46, XY , t(1; 19)(p32; p13); 46, XY, t(16; 18)(q22; q21); 46, XY, inv(1)(p36q25); 46, XY, t(13; 17)(q12; q25) and 46, XY, t(15; 21)(q26; q11). The chromosomal anomalies were the causes of spontaneous abortions and infertilities.  相似文献   
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本研究以辽宁绒山羊、柴达木绒山羊和柴达木山羊3个群体共147只山羊为研究对象,运用PAGE和RAPD技术对山羊的体重、绒产量和绒细度3个性状进行了与标记基因关系的遗传分析,结果表明:EsD2-2型、LAPBB型和PA-32-2型分别为体重、绒产量和绒细度性状的优势标记基因型;可利用标记辅助预测的方法充分利用多基因座标记基因间的互作效应;在体重上,寻找到有显著选择效应的RAPD条带11个,在绒产量和绒细度上分别为9和6个;在多目标性状选择中,CY0818/A0型和OPW19/C1型为体重和绒产量的双重优势RAPD标记,CY0818/G1型为体重和绒细度的双重优势RAPD标记。Abstract: The genetic relationships between economic traits and genetic markers were studied in 147 goats including Chaidamu goat (CS), Chaidamu Cashmere goat (CRS) and Liaoning Cashmere goat (LRS) in Qinghai province, China. CRS was the population of CS×LRS crossbred. The results showed as follows: the selection reaction of these blood protein polymorphisic loci were great, such as EsD, LAP and PA-3; and EsD2-2, LAPBB and PA-32-2 were the superior marker genotypes on body weight ,Cashmere yield and Cashmere fineness respectively by Least Square method. The interaction between marker genotypes at double loci was found frequently, and their ratio between interaction variance component and genetic variance was higher. With the method of marker assisted prediction( MAP), some interaction effect could be used effectively in the crossbreed population. On the aspect of random amplified polymorphic DNA (RAPD), the number of the superior RAPD marker bands were 11 on body weight trait, 9 and 6 RAPD marker bands on Cashmere yield and Cashmere fineness. For multi-goal traits, CY0818/A0 type and OPW19/C1 type were superior RAPD markers of body weight and Cashmere yield, CY0818/G1 type was superior one of body weight and Cashmere fineness.  相似文献   
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