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101.
中国对虾微卫星DNA的筛选 总被引：35，自引：5，他引：35
于2000年2月以中国科学院海洋研究所水族楼暂养的中国虾对材料，采用常规方法从尾部肌肉中提取DNA，构建小片段部分基因组文章，采用人工设计合成的（CT）7，（AT）7重复征段作引物，利用RCR法对中国对虾小片段部分基因组文库进行筛,一实验首冼 对中国对虾中获得31个微卫星序列，分别分析于18个阳性重组克隆中，其中perfect共23个，占74％，imperfect2个，占7％，compound perfect1个，占3％，compound imperfect5个，占16％，结果还表明，在中国对虾基因组DNA中，（CT）n,(AT)n)形式的微卫星序列的含量非常丰富。 相似文献
102.
103.
中国对虾肌肉含有快肌Ⅰ、快肌Ⅱ和慢肌等三类型肌纤维，其主要区别之处有：肌节长度、粗／细肌丝排列与比率、线粒体和二联体含量多寡以及ＡＴＰ酶活性等特征，文中已作详细描述。 相似文献
104.
ＩＮＴＲＯＤＵＣＴＩＯＮＰｒａｗｎｆａｒｍｉｎｇｉｎＣｈｉｎａｉｓａｎｉｍｐｏｒｔａｎｔｍａｒｉｃｕｌｔｕｒｅｉｎｄｕｓｔｒｙｗｈｏｓｅａｎｎｕａｌｐｒｏｄｕｃｔｉｏｎｈａｓｅｖｅｒｒｅａｃｈｅｄｔｏｍｏｒｅｔｈａｎ 2 .0× 1 0 5 ｔ,ｉｎｗｈｉｃｈｓｅｍｉ ｉｎｔｅｎｓｉｖｅｃｕｌｔｕｒｅｏｆＣｈｉｎｅｓｅｐｒａｗｎ (ＰｅｎａｅｕｓｏｒｉｅｎｔａｌｉｓＫｉｓｈｉｎｏｕｙｅ)ｃｏｎｔｒｉｂｕｔｅｄｔｈｅｇｒｅａｔｅｓｔｐａｒｔ.Ｂｕｔｉｎｒｅｃｅｎｔｙｅａｒｓｔｈｅｐｒａｗｎｃｕｌｔｕｒｅｉｎｄｕｓｔ… 相似文献
105.
This pathogenic study shows that the viral diseases of Chinese prawns (Penaeus chinensis. O'sbeck)is due to three kinds of viruses: epithelium envelope baculovirus of Penaeus chinensis (EEBV-PC, de-tected by the authors in 1993), infections hypodermal and hematopoietic necrosis virus, andhepatopancreatic parvo-like virus, and that the first two viruses seem to be the main pathogens of theepidemic in the northern regions in 1993. 相似文献
106.
Amplified fragment length polymorphism (AFLP) technique was used to analyze the fingerprinting of four successive generations
ofFenneropenaeus chinensis to reveal their disease-resistance traits. Some loci showed quite different genetic frequencies due to artificial selection,
which implied that these fragments were putative markers related to the disease-resistance trait. We developed a simple and
effective method to further characterize these AFLP fragments. Specific AFLP bands were cut directly from polyacrylamide gels,
re-amplified, cloned and sequenced. Eight putative genetic markers were sequenced and their sizes ranged from 63 to 209 bp.
The sequences were submitted to dbGSS (database of Genome Sequence Survey); and the BLAST analysis showed low similarity to
the function genes, indicating these markers were tightly linked to a disease-resistance trait but were not functional genes.
This research was supported by special funds from the National Key Basic Research Program (G1999012007) and the National High-Tech
Research and Development Program of China (863 Program. 2001AA620105). 相似文献
107.
The viral disease of penaeids is indistinct but highly dangerous because their symptoms are often masked by some secondary ones.In order to gain knowledge on how to prevent the occurrence and spread of this viral disease, diagnostic studies on the early phase of the hepatopancreatic parvo-like viral (HPV)disease of cultured Penaeus chinensis was conducted using immuno-serological techniques. The purification of HPV was successfully done by density gradient ultracentrifugation of cane sugar. 相似文献
108.
黄连种植对生态环境影响的初步研究 总被引：4，自引：0，他引：4
黄连对生境要求特殊，其生产完全依赖于森林资源的消耗，每种1hm^2黄连要破坏3hm^2林地，消耗150m^3木材，每个种植阶段都会引起较严重的水土流失，其中第一年的土壤侵蚀模数为5360t／km^2。在重庆市石柱县黄连主产区黄水镇，由于历年来一直种植黄连，野生动物生存环境长期受到破坏，沟河鱼类资源2001年比1981年减少。73％，有8种大型陆生脊椎动物绝迹，而一些食草性动物的数量近年有所增加。 相似文献
109.
The accumulation of Pb in the food chain is one of the great concerns as it can cause chronic health problems and the available Pb is easily absorbed by crops. To shed light on Pb bioavailability in lead-contaminated agricultural soils of Zhejiang Province, a series of plant growth experiments were performed in a greenhouse to select more suitable extractants from five commonly used extractants (0.1 M HCl, 1 M NH4OAc, 0.1 M CaCl2, DTPA-TEA and Mehlich 3). The results showed that 1 M NH4OAc can extract Pb best, indicating the Pb bioavailability, then, DTPA-TEA and 0.1 M HCl in the tested soils. In case 1 M NH4OAc was used as an extractant, the critical Pb concentrations in soils were 50.19 mg/kg, 21.16 mg/kg and 114.00 mg/kg (1 M NH4OAc extracted Pb) in silty loam, yellowish-red soil and purplish soil, respectively. When the values exceed the above ones, the contents of Pb in Chinese cabbage leaves will exceed the Chinese Tolerance Limit of Lead in Foods (GB14935-94), as a result, potential ecological risk and hazard to human health via the food chain will appear. 相似文献
110.