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排序方式: 共有921条查询结果,搜索用时 15 毫秒
1.
小鼠H-Y单克隆抗体ELISA检测方法的建立 总被引:2,自引:0,他引:2
以纯系 BAL B/ c雄性小鼠脾细胞腹腔注射免疫同系雌性小鼠 9次 ,获得的抗血清经雌、雄鼠脾细胞吸收后用于精子细胞毒性试验 ,测得 H- Y抗血清效价为 1/ 16 0。选取免疫应答最好的雌鼠脾细胞与 SP2 / 0骨髓瘤细胞融合 ,用精子细胞毒性方法筛选效价较高的细胞株制备腹水 ,建立优化的 EL ISA反应条件。优化后的 EL ISA反应条件为 :抗原4℃过夜 ,加 H- Y抗血清 37℃反应 12 0 m in,加 HRP- Ig G 37℃反应 30 min,加 TMB 2 5℃ 30 min。优化后的 EL ISA与常规 EL ISA比较 ,可以明显降低阴性吸光值 ,检测灵敏度从 1/ 32 0上升为 1/ 12 80 相似文献
2.
水牛精子在胞质内注射后的早期形态变化 总被引:1,自引:0,他引:1
应用胞质内精子注射 (intracytoplasmic sperm injection,ICSI)技术探讨了水牛卵母细胞胞质与注射精子间的相互作用以及 ICSI精子的形态变化。ICSI后 13h,5 9.4 %的精子头部已膨大 ,且有 18.8%的精子进入解聚状态。雌雄原核发育不同步 ,雄原核在 ICSI后 16 h和 19h的形成率分别为 3.2 %和 4 0 .0 % ;雌原核在 ICSI后 13h已达到 71.9% ,16 h时提高到 90 .3%。经离子霉素与 6 - DMAP联合激活 ,ICSI后 19h产生的胚胎核型以 2 PN PB1 为主 ,其雌原核形成 (激活 )率为 91.3% ,雄原核形成率为 4 0 .0 % ,5 1.3%为孤雌胚。用 5 mm ol/ L 的 DTT预处理精子 1h,可提高精子的解聚率 (30 .9%比 12 .7% ,P<0 .0 5 ) ,但对雄原核的形成率无显著影响 (33.3%比 32 .7% ,P>0 .0 5 )。结果表明 ,水牛精子 ICSI后的雄原核形成时间晚于卵子雌原核形成时间 ,且其比率低于卵子 ,DTT处理精子能提高其解聚率 ,但对雄原核形成无影响 相似文献
3.
In vitro studies of Norwegian Red bovine semen immobilized and cryopreserved in alginate solid gel network 下载免费PDF全文
AH Alm‐Kristiansen ER Gaustad G Bai FB Standerholen G Klinkenberg E Kommisrud KE Waterhouse 《Reproduction in domestic animals》2018,53(2):365-370
Development of new semen cryopreservation techniques improving sperm survival and ensuring availability of viable spermatozoa for a prolonged time‐period after AI is promising tools to reduce sensitivity of timing of AI and enhance overall fertility. The SpermVital® technology utilizes immobilization of bull spermatozoa in a solid network of alginate gel prior to freezing, which will provide a gradual release of spermatozoa after AI. The objective of this study was to compare post‐thaw sperm quality and in vitro sperm survival over time of Norwegian Red bull semen processed by the SpermVital® (SV) technology, the first commercialized production line of SpermVital® (C) and by conventional procedure applying Biladyl® extender (B). Post‐thaw sperm motility was not significantly different between SV, C and B semen (p > .05). However, sperm viability and acrosome intactness were higher for SV than C and B semen (p < .05). Small differences in DNA quality were observed (p < .05). Sperm viability after storage in uterus ex vivo was higher for SV than for C semen (p < .05). Furthermore, sperm survival in vitro over time at physiological temperature was significantly higher for SV semen than C semen as well as B semen during the incubation period of 48 hr (p < .05). In conclusion, the SpermVital® technology is improved and is more efficient in conserving post‐thaw sperm quality and results in higher sperm viability over time in vitro for SV than for C and B semen. 相似文献
4.
Disaccharide combinations and the expression of enolase3 and plasma membrane Ca2+ ATPase isoform in sturgeon sperm cryopreservation 下载免费PDF全文
Acipenser sinensis and Acipenser dabryanus are critically endangered species, so germplasm conservation via cryopreservation of sperm is necessary. Disaccharides can act as membrane‐impermeable cryoprotectants, and enolase3 (ENO3) and plasma membrane Ca2+ ATPase isoform (PMCA2) are proteins associated with sperm quality. We considered seven characteristics of sperm quality in cultured brood stock from A. sinensis and A. dabryanus. We tested use of sucrose or trehalose alone and in combination at different concentrations for cryopreservation of A. dabryanus sperm. A low concentration of sucrose plus trehalose (S15T15) was optimal. Mixing of the extender with sucrose, lactose, or trehalose alone or with pairwise mixtures revealed that a mixture of lactose and trehalose (L15T15) gave the best results for both A. sinensis and A. dabryanus. Enolase3 and PMCA2 expression levels were measured in cryopreserved A. sinensis sperm via Western blotting. Relative ENO3 and PMCA2 expression levels were examined, and the relationship between disaccharide composition, sperm quality and protein expression was explored in A. sinensis. The results showed that relative ENO3 and PMCA2 expression levels were the highest at L15T15 in cryopreserved A. sinensis sperm. There were significant positive correlations between ENO3 expression and percentage membrane integrity, and between PMCA2 expression and sperm motility parameters (percentage of motile sperm, curvilinear velocity, straight‐line velocity and average path velocity; p < .05) in cryopreserved A. sinensis sperm. Our results indicate the optimal disaccharide combination and concentrations for cryopreservation of A. sinensis and A. dabryanus sperm and suggest that ENO3 and PMCA2 expression levels could serve as a valuable indicator of sperm quality in A. sinensis. 相似文献
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旨在建立可以定量计算奶山羊精液中X、Y精子数量的双重TaqMan荧光定量PCR方法,用以检测经过分离的奶山羊精液X和Y精子的数量和比例,为性控技术的开发和生产应用提供技术支撑。本研究选择X、Y染色体中特异基因F9及ZFY片段设计引物,建立标准曲线,优化荧光定量PCR反应体系和条件。通过对阳性标准品梯度稀释以及对60支已知纯度的性控精液进行测定(3次重复)来检验方法的敏感性和可靠性。结果显示,所建立的双重TaqMan荧光定量PCR方法特异性和重复性好,X和Y精子检测灵敏性分别为47和51 copies·μL-1;利用该方法对商品化的奶山羊性控冷冻精液中X和Y精子的数量和比例进行计算,其结果与销售公司提供的X和Y精子的纯度无显著差异(P>0.05),表明该方法结果可靠。本研究建立的计算奶山羊X、Y精子数量的双重TaqMan荧光定量PCR方法特异性和重复性好,灵敏度高,结果可靠,为计算奶山羊精液分离后X、Y精子数量及比例提供了快速可靠的方法。 相似文献
8.
Maryam Moradi Hadi Hajarian Hamed Karamishabankareh Leila Soltani Bijan Soleymani 《Reproduction in domestic animals》2021,56(2):263-269
Pre-conceptual sex selection is still a highly debatable process whereby X and Y chromosome bearing spermatozoa are isolated before oocyte fertilization. Recently, magnetic nanoparticles (MNP) have been used to determine X and Y chromosomes bearing spermatozoa as a result of searching for a cheap, highly efficient method using non-toxic materials. This study aimed to recover the sperm bearing X chromosomes in ram with different concentrations of MNP and then evaluate the success of this method using polymerase chain reaction (PCR). Ram sperms were divided into four groups, treated with 0 (control), 50, 100 and 200 μg/ml MNP, respectively. MNP was used to restore sperm cells bearing X chromosomes. Upon recovery, the PCR was performed to identify the X and Y sperms, Methyl ThiazoleTetrazolium (MTT), to assess MNP toxicity and sperm viability and acridine orange (AO) to evaluate sperm DNA integrity. The results of PCR revealed that the treatment of spermatozoa- bearing X chromosomes with 50 μg/ml MNP had the highest effects on the recovery of X sperm rather than the other concentrations of MNP. However, the concentrations of MNP did not have any toxic effects on spermatozoa, sperm viability and, DNA integrity, but the high concentration of MNP (200 μg/ml) significantly reduced DNA integrity. According to MTT and AO results, the concentrations of MNP used in this study had no toxic effects on spermatozoa and did not reduce the sperm viability and DNA integrity, except that 200 μg/ml MNP significantly reduced DNA integrity. 相似文献
9.
Bijan Soleymani Kamran Mansouri Mohsen Rastegari-Pouyani Shahram Parvaneh Fatemeh Khademi Mehdi Sharifi Tabar Ali Mostafaie 《Reproduction in domestic animals》2021,56(2):270-277
Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms. 相似文献
10.
Ziyad Al-Kass Alexander Brown Anders Johannisson Theodoros Ntallaris Jane M. Morrell 《Reproduction in domestic animals》2021,56(6):848-856
Although single layer centrifugation (SLC) selects robust spermatozoa from stallion semen, the effect of individual variation has not been studied in detail. The objective of this study was to determine the variation among stallions in the effects of SLC on sperm quality during cooled storage for up to 48 hr. Semen samples from seven stallions (18 ejaculates) were split, with one portion being used for SLC and the other serving as a control (CON). Sperm quality (kinematics, reactive oxygen species (ROS) production, membrane integrity (MI) and chromatin integrity) were analysed at 0, 24 and 48 hr using computer-assisted sperm analysis and flow cytometry. Sperm quality was better in SLC than in CON at all timepoints, especially chromatin integrity and MI (p < .0001 for both), and some categories of ROS production (e.g. proportion of live hydrogen peroxide negative spermatozoa, p < .0001), but the degree of improvement varied among stallions and type of ROS (p < .05–p < .0001). Total and progressive motility were also better in SLC samples than in CON at 24 and 48 hr (p < .0001), although the effect on sperm kinematics varied. The interaction of treatment, time and stallion was not significant. In conclusion, sperm quality was better in SLC samples than in CON, although there was considerable individual variation among stallions. The improvement in sperm quality, particularly in chromatin integrity, was clearly beneficial, and therefore the use of this technique would be warranted for all stallion semen samples. 相似文献