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奶牛胚胎性别控制技术的试验研究进展 总被引:13,自引:2,他引:13
应用LAMP法进行了613枚胚胎的性别鉴定结果,雌性胚胎302枚(49.3%),雄性胚胎311枚(50.7%),移植成功率平均为40.9%(122/298),出生后代中与性别鉴定结果一致的121头,性别鉴定准确率为96.0%(121/126)。应用奶牛性腔胶囊后输精的14头供体母牛,共采集69枚可用胚胎,对其中64枚胚胎进行性别鉴定,确定雌性胚胎的比例为71.9%(46/64),头均获4.9枚可用胚胎。应用奶牛性控液对3头供体母牛宫注后输精,共采集26枚可用胚胎,经性别鉴定后确定雌性胚胎比例为73.1%(19/26),头均获可用胚胎8.7枚。应用分离X精子冷冻精液对12头供体母牛进行输精,对采集到的61枚胚胎进行性别鉴定后,确定雌性胚胎比例为100%(61/61),头均获得可用胚胎5.5枚。11枚性控冷冻胚胎移植后,40d以上未返情率为63.6%(7/11)。用分离的X精子冷冻精液对供体母牛输精后,可获得与未分离冷冻精液输精后相接近的超排供体母牛采集胚胎的数量和质量。 相似文献
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阐释了园林构成要素中的必然性要素和偶然性要素及其相互关系与运用意义;以昆明世博园中“齐鲁园”为例,辩识了“齐鲁园”中必然性与偶然性园林要素,分析了诸要素在特定园林环境布局中的运用。 相似文献
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ZHOU Shu-lu YE Ren-gao LIU Xiao-bo ZHANG Hong XU Han-shi DU Yong LI You-ji YANG Nian-sheng YANG Xiao YU Xue-qing 《园艺学报》2003,19(6):782-785
AIM:To detect the association between the polymorphism of Fc receptor γ chain gene at position-29 in promoter and systemic lupus erythematosus(SLE).METHODS:The genotypes at position -29 in promoter of Fc receptor γ chain gene were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 180 patients with SLE and 140 ethnically matched controls in southern China.RESULTS:The frequencies of TT genotype(33.3%) and T allele (54.4%) at position -29 in patients with SLE were significantly higher than those in controls (17.2% and 42.9%, respectively), whereas, the frequencies of GG genotype (24.4%) and G allele (45.6%) in patients with SLE were remarkably lower than those in controls (31.4% and 57.1%, respectively) (P<0.05). The TT genotype and T allele at position -29 were not associated with lupus nephritis in SLE patients (P>0.05).CONCLUSION:Our results indicate that the T allele at position -29 in promoter of Fc receptor gene probably contributes to the susceptibility to SLE, but does not play a role in the occurrence of lupus nephritis. 相似文献
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AIM:To establish cell line FL-POLκ- and to study the role ofPOLκ(polymerase kappa) on genetic stability.METHODS:A mammalian expression vector expressing antisense POLκ gene fragment pMAMneo -amp--POLκ was constructed by cloning the 1 690-1 918 fragment of POLκ gene into the mammalian expression vector pMAMneo-amp- in antisense orientation. FL cells were fransfected with this antisense RNA expressing vector and selected by G418. Based on the shuttle-plasmid pZ189, the mutation assay was made.RESULTS:The spontaneous mutation frequency of supF tRNA gene in the plasmid replicated in the FL- POLκ- was 11.2×10-4, while it was 4.9×10-4 and 3.7×10-4 in the control cells FL and FL-M, respectively.CONCLUSION: POLκ playes an important role in maintenance of genetic stability. 相似文献
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AIM: To investigate the application of atomic force microscope (AFM) in clinic diagnosis. METHODS: Topographic images and some parameters of large range field and microstructures of erythrocytes in the blood of normal subjects, lung cancer and myelodisplastic syndrome (MDS) patients were examined by atomic force microscope. RESULTS: Many clear topographic images of many erythrocytes, single erythrocyte, and microstructure of erythrocyte membrane surface were obtained. Many erythrocytes in lung cancer patients were found to change into echinocytes. One erythrocyte had 10-20 protuberances, most of which, with a mean width of 589. 0 nm and a length of 646. 7 nm, were on the edge of cells. The protuberances on the center of echinocytes are lodged and embedded. The erythrocytes of MDS patients were biconcave in shape. Many apertures with different diameters of tens to hundreds nanometer appeared on the surface of cell membrane. CONCLUSIONS: AFM can be widely applied in clinic pathological inspection, including quantification of cells, obtainment and comparison of many parameters (such as diameter, thickness, volume, surface, surface area/volume ratio), observation of topograph of single cell, and observation and comparison of membrane surface microstructure of cells, and so on. 相似文献
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HEI Zi-qing WU Wei-kang SUN Hui-lan HUANG He-qing TAN Hong-mei LUO Han-chuan 《园艺学报》2003,19(3):345-347
AIM:To observe the effects of Sini decoction on atherosclerosis(AS) and ceramide content of aorta in rabbits. METHODS:28 rabbits were randomly divided into three groups. Control group was fed with a normal diet; High cholesterol group was fed 1% cholesterol and 5% fat diet; Sini decotion+ high cholesterol group was fed 1% cholesterol and 5% fat diet plus Sini decotion (4.2 g·kg-1·d-1). At the end of study, the plaque area were measured, the atorta ceramide and cell apoptosis were also detected. RESULTS:Sini decotion diminished lipid plaque area on the aortic endothelium, reduced the levels of aorta ceramide and the apoptosis index. CONCLUSION:Sini decoction has an inhibitory effect on AS, the mechanism may be that Sini decotion reduces concentration of ceramide in aorta. 相似文献