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31.
微胚乳玉米子粒显微结构研究 总被引:1,自引:0,他引:1
Twenty four lines of 5 types maize were used to study the micro-structure in ripe kernel of MEM(micro-endosperm super high oil maize),weight ratio of embryo to kernel,and the different characteristics of micro-structure between MEM and the other 4 non-MEM.The results indicated that the endosperm contents of MEM were very few.Some of them even had no endosperm(except aleurone layer).It illustrated that some of the MEM showed degenerative endosperm,but their embryos were the biggest among the 5-type maize.At the same time,the weight ratio of embryo to kernel of MEM was also the maximum in 5-type maize. 相似文献
32.
动物胚胎移植实际是生产胚胎的供体和养育胚胎的受体分工合作繁殖后代的过程。其目的是使经济效益低、生产性能不高、不符合社会需要和人们生活需求的母畜作为受体生产出经济效益高、生产性能好、符合社会和人们需求的良种后代,以便迅速增加良种畜禽的数量,大大提高受体母畜的繁殖效率和经济效益。本文就国内外和甘肃省的胚胎移植技术发展概况进行阐述,并从胚胎移植推广应用角度分析了胚胎移植技术存在的主要问题。 相似文献
33.
采用刀片破皮、低温冷冻、60℃热水浴及干燥、碱液处理、浓硫酸加搅拌等方法处理野生大豆种子,研究其对野生大豆种子发芽和胚生长的影响。结果表明:经过刀片破皮和浓硫酸加搅拌处理的各项萌发指标远高于对照(P0.05);综合野生大豆幼苗的萌发指标和胚根长、胚芽及鲜重等指标,破皮和10 m in浓硫酸加搅拌处理最有利于野生大豆种子萌发;冷冻处理的各项萌发指标显著低于对照(P0.05),与常温保存相比,冷藏保存野生大豆种子的千粒重和发芽率有所增加。表明冷藏保存可以提高野生大豆种子的质量;常温下野生大豆休眠期为7个月,冷藏保存野生大豆的休眠期为8个月。 相似文献
34.
《园艺学报》2003,19(5):622-626
AIM: To detect quickly the Y-chromosome specific sex determining region protein (Sry) gene in mouse fetuses on embryonic day 14.5 with a PCR method. METHODS: We designed specific primers with the OLIGO 5. 0 software. Templates were prepared in 30 minutes by the following way. About 1 mg embryonic tissue but not fetal liver was suspended, and treated with 200μL of lysis buffer, consisting of PCR buffer containing 20 mg/L proteinase K, 0. 5% NP-40, and 0.05% Tween 40, at 60°C for 15 minutes, heated for 5 minutes at 100 °C, 10μL was used as template. The PCR react ion was performed in 50μL, using two sets of primers specific for Sry gene (chromosome Y) and IL-3 gene (chromosome 11) . PCR conditions and cycle numbers were optimized. The assessment of the results was done by electrophoresis in 3% agarose run at high voltage. The specificity of the method was conf irmed by fluorescent in situ hybridization (FISH) using a specific male probe on embryonic tissue cells. RESULTS: Electrophoresis showed that PCR product of male control DNA consisted of a 649 bp product representing the IL-3 gene and a 444 bp product representing the Y-specific Sry gene, female control DNA only one 649 bp product. Fetuses with two bands matching those as seen inmale control DNA are the presumpt ive male fetuses. Fetuses, only the IL-3-associated 649 bp band, are the presumptive female fetuses. These were confirmed by FISH. The ent ire procedure took <3. 5 h. CONCLUSION: The established PCR assay offers a quick, simple, accurate, and sensitive detection of sex determining region protein gene in mouse fetuses. This method allowed the preparation and culture of pure male and female hematopoietic stem cells from fetal tissue. 相似文献
35.
36.
M. Moussa DVM PhD G. Duchamp P.F. Daels DVM PhD Dipl ACT ECAR J-F. Bruyas DVM PhD Dipl ECAR 《Journal of Equine Veterinary Science》2006,26(11):529-534
The aim of this study was to compare the viability of 7- and 8-day-old equine embryos cooled and stored for 6 or 24 hours in two different transport systems. Embryos (n = 97) were recovered on day 7 or 8 and assigned to 10 groups (n = 10/group). Embryos within the same age group (D7 or D8) were evaluated immediately after collection (Group-0h) or after storage in an Equitainer at 5°C for 24 hours in 5 ml Emcare Holding Solution (EHS) (Group-E-24h) or 5 ml Ham's F10 (Group-H-24h) or in a refrigerator at 5°C in 500 ml Emcare Flushing Solution (EFS) for 6 hours (Group-B-6h) or 24 hours (Group-B-24h). After collection or storage, embryos were incubated in 1 μg/ml DAPI to determine the percentage of dead cells per embryo (DAPI positive, fluorescent cells). Subsequently, embryos were fixed in 4% paraformaldehyde and re-stained with DAPI to determine the total number of cells. The percentage of dead cells in group-0h and B-6h was similar and significantly lower than for embryos stored for 24 hours in groups B-24h, E-24h, and H-24h. The percentage of dead cells was similar for embryos stored in an Equitainer (groups E-24h and H-24h) and was significantly higher for embryos stored 24 hours in EFS (Group B-24h). Within each storage system (0h, B-6h, B-24h, E-24h, and H-24h) no significant difference in the percentage of dead cells was observed between 7- and 8-day-old embryos. Storage in 500 ml EFS at 5°C for 6 hours resulted in embryos of better quality than after the traditional 24-hour storage in an Equitainer, suggesting that this simplified system offers a good alternative for short-term storage and transport. 相似文献
37.
38.
以萝卜雄性不育系DH303A为母本,以苤蓝为父本进行属间远缘杂交,萝卜与苤蓝杂交的不亲和性发生在胚珠发育过程中,杂交荚荚长快速生长期在授粉后的第2~5天,而横径快速生长期在授粉后第2~4天。在杂种胚发育后第6天和第7天进行胚抢救,用诱导培养基:MS+2,4-D 2.0 mg/L+KT 0.5 mg/L+蔗糖3%+琼脂0.6%;继代培养基:MS+2,4-D 2.0 mg/L+KT 0.5 mg/L+蔗糖3%+琼脂0.6%;分化培养基:MS+IAA 0.5 mg/L+KT 1.5 mg/L+蔗糖3%+琼脂0.6%;生根培养基:MS+NAA 0.2 mg/L+IAA 0.5 mg/L+蔗糖3%+琼脂0.6%,能成功获得幼苗。 相似文献
39.
胚胎移植波尔山羊早期生长发育的研究 总被引:1,自引:0,他引:1
[目的]初步掌握胚胎移植波尔山羊的生长发育规律。[方法]以胚胎移植生产的波尔山羊为试验动物,同期出生的自然繁殖波尔山羊为对照,分别测定波尔山羊的初生重、1月龄、3月和6月龄体重,3月龄和6月龄波尔山羊体尺,并观察记录羊只的健康状况。[结果]胚胎移植波尔山羊在正常饲喂条件下,早期生长发育快,肉用体型明显;公羔平均初生重为(4.25±0.95)kg,母羔为(3.74±0.10)kg,6月龄公羊平均体重为(31.90±0.74)kg,母羊为(25.90±0.67)kg,从出生到6月龄的日增重,公、母羊分别为153.64、123.11g;体长、体高、胸围等增加明显。体重、体尺测定结果与自然繁殖羔羊差异不显著。[结论]该研究为进一步探讨胚胎移植波尔山羊早期的选种利用奠定基础。 相似文献
40.
Effect of acupuncture on CD4+ CD25+ Foxp3+ regulatory T-cells in rats of embryo implantation failure
GAO Wei-na GUO Yue WANG Li-jun TANG Xiao LIU Ya-fei CHEN Zhen-yan ZHANG Ming-min HUANG Guang-ying 《园艺学报》2013,29(8):1464-1470
AIM:To observe the effect of acupuncture on CD4+ CD25+ Foxp3(forkhead box P3)+ regulatory T-cells(Treg cells) in rats with embryo implantation failure. METHODS:One hundred and forty-four pregnant rats were randomly divided into control group(N), mifepristone treatment group(M), mifepristone+acupuncture treatment group(A) and mifepristone+progestin treatment group(W). The rats in groups M, A and W were treated with mifepristone-sesame oil solution on day 1, while the rats in group N were injected with the same amount of sesame oil. The Housanli(ST36) and Sanyinjiao(SP6) points were selected for acupuncture. From day 1 to the time of death, the rats in group A were fasten up and then the acupuncture was performed. Accordingly, the rats in group N and group M were only fixed, and the rats in group W were given progestin. Implanted embryos in each group were counted. The proportions of CD4+ CD25+ Foxp3+ Treg cells in peripheral blood and CD4+ Foxp3+ Treg cells in the endometrium were detected by flow cytometry. The mRNA and protein levels of Foxp3 were determined by real-time PCR and Western blotting, respectively. RESULTS:Compared with group N, the number of implanted embryos, the percentages of CD4+ CD25+ Foxp3+ Treg cells in peripheral blood and CD4+ Foxp3+ Treg cells in the endometrium, and the expression of Foxp3 protein and mRNA in the endometrium were significantly decreased in group M(P<005). Compared with group M, the above indexes in group A and group W were significantly increased. CONCLUSION: The effect of acupuncture in rats with embryo implantation failure may be closely correlated with the modulation of CD4+ CD25+ Foxp3+ Treg cells. 相似文献