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排序方式: 共有616条查询结果,搜索用时 31 毫秒
31.
LiuDi ChenXuehui 《东北农业大学学报(英文版)》1998,5(2):146-152
The patterns of cleavage of mtDNA by restriction endonucleases was analysed for six fowl breeds and of .Hyline White,Hyline Brown,ISA Brown,Hisex Brown,Lohmann White,Abor Acres and mtDNA polymorphisms were detected in the restriction patterns with the following eight enzymes,Ava Ⅰ,AvaⅡ,EcoRⅠ,HindⅢ,BamHI,PvuⅡ,PstⅠ,HincⅡ.The restriction cieavage patterns were identical among these breeds.Hyline White,Hyline Brown,ISA Brown,Hisex Brown,Lohmann White-A type.The patterns of Abor Acres were Btype.Based on their mtDNA restriction types,all the breeds were classified into two groups.Genetic distances among these groups were calculated in roder to define their phylogenetic relationships.The relationship among five egg line breeds is close,while Abor Acres(Broiler fow)is relatively far from them.The results suggest that the difference of mtDNA could result from the different origins.The polymorphic sites in mtDNA of Hyline White bas been located on a restriction map. 相似文献
32.
针对哈尔滨市南岗区果戈里大街的路面设计、施工状况的调查,分析了沥青路面裂缝原因与几个因素的关系,并结合有关资料提出一些防治措施。 相似文献
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Thermal stratification negatively affects water quality, and thus is a threatto fish culture in deep water ponds and reservoirs. To prevent and controlit, a device based on an underwater propeller that vertically transportsoxygen rich warm water from the epilimnion down to the anoxic and colderhypolimnion was assembled. The empirical results so far obtained in Israelidual purpose reservoirs for field crop irrigation and fish culture aresummarized herein, and a mathematical model of the device's effect onreservoir thermal structure is presented. 相似文献
35.
Meg D. Sislak Kathy A. Spaulding Debra L. Zoran John E. Bauer James A. Thompson 《Veterinary radiology & ultrasound》2014,55(2):195-201
Echoes are frequently seen in the urinary bladder of cats during abdominal ultrasound. These have been attributed to hematuria, pyuria, crystalluria, and lipid. However, sonographic findings have not been previously correlated with urinalysis. We prospectively evaluated 40 clinically normal cats via ultrasound, serum chemistry, and urinalysis. Thin layer chromatography was performed on the urine to determine the amount (mg) of lipid subfractions including diacylglycerol, triglyceride, phospholipid, free fatty acid, cholesterol, and cholesterol ester. Ninety percent (36/40) of the cats in our population had sonographic echoes suspended in the urinary bladder, with most having a subjective score of mild echoes (n = 20). None of the sonographic echoes were gravity dependent or caused distal acoustic shadowing, reverberation, or twinkle artifact. Of the cats with sonographic echoes in the urine, 66% (24/36) had no significant findings on urinalysis other than the presence of lipid. The total amount of subjective sonographic echoes was not significantly related to the total amount of fat measured on thin layer chromatography or the number of lipid droplets seen on urinalysis. An increased amount of urine diacylglycerol was significantly associated with clumping of echoes (P = 0.02) and the amount of lipid droplets seen on urinalysis (P = 0.04). An association between increased amounts of urine diacylglycerol and the amount of echoes seen on ultrasound approached significance (P = 0.05). Findings from this study support previously published theories that sonographic echoes within the urinary bladder of clinically normal cats may be due to urine lipid. 相似文献
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结合施工中的实例,本阐述了施工中监理进行全过程工艺控制的方法及对策。并说明了现阶段监理做姨全过程施工工艺控制,可以实现工程质量、进度、投资、费用、工期最大程度的优化。 相似文献
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中国1923~1995年育成的651个大豆品种的遗传基础 总被引:13,自引:0,他引:13
从1923~1995年中国651个大豆育成品种(包括东北330、黄淮海210、南方111个)的系谱归纳出348个祖先亲本,育成品种归属为348个细胞核家族和214个细胞质家族。全国每个育成品种实际使用的祖先亲本数由1960年前的平均1.59个增至1991~1995年的平均6.39个,总平均3.79个。从一个地区的祖先亲本总数着眼,东北、黄淮海、南方平均每个育成品种拥有的细胞核和细胞质祖先亲本数分别是0.50、0.25、0.71和0.40、0.97、0.54个。祖先亲本的遗传贡献并不平衡,各区均有少数祖先亲本在育成品种中占很大遗传份额,东北地区尤为突出。黑龙江、山东、吉林、江苏等省大豆育成品种的细胞质来源均较为简单。 相似文献
40.
中国大豆育成品种中江苏种质58—161的遗传贡献 总被引:13,自引:1,他引:12
由原中国农科院江苏分院育成品种58-161作为直接亲本衍生出12个品种,由它们进一步又衍生出49个品种,其中有29个接受了58-161的细胞质。这61个品种可归为5类系谱。 相似文献