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1.
超排方法及兔龄对家兔超排效果的影响 总被引:9,自引:0,他引:9
采用国产促卵泡激素(FSH),促黄体激素(LH)和人绒毛膜促性腺激素(HCG),分别以FSH LH(A法),FSH HCG(B法)两种不同的处理方法,对不同年龄的家兔进行超排处理,旨在选择对家兔有效的超排方法,比较兔龄对超排效果的影响。结果表明,用A法对经产母兔和青年母兔处理后的排卵数分别为68枚,46枚;回收胚胎数分别为36枚,15枚;有效胚胎数分别为27枚,10枚,用B法对经产母兔和青年母兔处理后的排卵数分别为93枚,71枚;回收胚胎数分别为59枚,37枚,有效胚胎数分别为45枚。26枚。以上指标均以FSH HCG组最高,经产兔超排效果较青年兔好。 相似文献
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表达大肠杆菌K88ac-ST1-LTB融合蛋白工程菌株的免疫原性研究 总被引:2,自引:0,他引:2
已构建的能表达大肠杆菌K88ac-ST1-LTB融合蛋白的工程菌株BL21(DE3)(pXKST3LT5)及其表达产物经动物试验证实没有毒性反应。用从IPTG诱导的工程菌中提取的包涵体或经甲醛灭活的工程菌制成抗原,免疫小鼠,结果免疫小鼠至少能抵抗2MLD的大肠杆菌强毒株C83902(K88ac,ST^ ,L^ )的攻击,用提取的包涵体免疫家兔后,采集的血清能够中和天然ST1的毒性,这表明构建的工程菌株BL21(DE3)(pXKST3LT5)可以作为预防幼畜大肠杆菌性腹泻基因工程菌苗的候选株。 相似文献
4.
采用A-PAGE和SDS-PAGE聚丙烯酰胺凝胶电泳方法,对远缘组合分离出来的节燕98-2类型入选11个遗传性基本稳定的具有高产、多抗的小麦株系的醇溶蛋白和高分子量谷蛋白亚基进行了分析.结果表明,在A-PAGE电泳分析中,11个供试株系具有11种不同的醇溶蛋白带型.在SDS-FAGE电泳分析中,出现了7种不同的高分子量谷蛋白亚基(HMW-GS)及6种亚基组合类型,优质亚基及亚基组合所占的比例较少,品质评分偏低,其变幅为5~8分,平均为6.36分.但在所分析的材料中,出现了一个少见的特殊亚基:2 10 12.并研究了这些HMW-GS和组合频率及特点.11个株系中7个具有45 10优质亚基和2个具有2*亚基,它们可供小麦优质育种利用.研究表明,通过远缘杂交能够选育出具有高产、抗病和优质的小麦新材料. 相似文献
5.
A radioimmunoassay for llama and alpaca LH was developed using a human I125LH tracer from a commercial kit, equine LH diluted in human LH free serum as standard, and a monoclonal antibody (518B7) specific for LH but with low species specificity. A 60-min delay in the addition of the tracer and overnight incubation gave a sensitivity of 0.8 μg L−1. The intra-assay coefficient of variation was 37% at 1 μg L−1, declined to 15% at 4 pg L−1 and was below 6% for concentrations up to 32 μg L−1. The inter-assay coefficients of variation for 3 control samples were 20% (2.8 μg L−1), 16% (7.1 μg L−1) and 9.8% (19 μg L−1). In an attempt to increase sensitivity, all tubes were preincubated for 4 h at room temperature before adding the tracer, and the sample volume was increased from 50 μL to 100 μL· (in the standard curve the increased volume was compensated for by human LH free serum). With this protocol, the assay sensitivity was 0.5 μg L−1. The assay was validated clinically and demonstrated increased concentrations of LH after mating in llamas and alpacas. Furthermore, the assay was used to monitor LH responses to a single dose of GnRH in llamas (adult males and females at different ages). 相似文献
6.
为了解江苏省小麦品种的谷蛋白亚基组成现状,为品质育种提供理论指导,选用77份来自江苏省淮南和淮北主要小麦育种单位的育成品种或高代品系,利用聚丙烯酰胺凝胶电泳法(SDS-PAGE)对Glu-1和Glu-3位点进行了鉴定。结果表明,参试品种(系)Glu-1和Glu-3位点的高分子量麦谷蛋白亚基(HMW-GS)和低分子量麦谷蛋白亚基(LMW-GS)变异丰富。共检测到12个HMW-GS等位变异,其中Glu-A1位点有3个,Glu-B1位点有5个,Glu-D1位点有4个。LMW-GS的Glu-A3和Glu-B3位点则分别检测到5个和6个等位变异。淮北小麦的HMW-GS多态性高于淮南小麦。Glu-1和Glu-3位点等位变异的分布频率差异较大,且淮北和淮南表现不同,优质亚基比例较低。Glu-1位点主要亚基类型为0(46.8%)、1(49.4%)、7+8(63.6%)和2+12(63.6%),Glu-A3位点主要亚基类型为a(23.4%)、c(57.1%)和d(15.6%),Glu-B3位点主要亚基类型为b(22.1%)、f(49.4%)和j(1B/1R易位)(16.9%)。淮北小麦的高分子量谷蛋白优质亚基及亚基组合较少,Glu-B3j分布频率高(54.5%),亚基质量有待提高;淮南小麦的优质亚基及组成亦较少,需根据中筋和弱筋小麦育种目标并结合蛋白质含量和亚基选择进行改良。 相似文献
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Peru Gopal BISWAS Yuma OHARI Uday Kumar MOHANTA Tadashi ITAGAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):666
We analyzed the nuclear ribosomal internal transcribed spacer (ITS) 1 and ITS2 sequences for Bangladesh isolates of Ascaridia galli, and we determined that the sequences were unreliable as molecular markers for distinguishing A. galli from other Ascaridia species, because the sequences showed high identity with that of A. columbae. However, the ITS1 sequences were available for designing PCR primers distinguishable between Ascaridia galli and Heterakis spp. Bangladesh isolates of A. galli constituted a monophyletic clade along with other geographical isolates in the cytochrome c oxidase subunit I (COI) phylogenetic tree, however, we could not clarify the phylogenetic relationships between A. galli and other Ascaridia spp., because their available sequences in GenBank were very few. The developed PCR method using DNA from A. galli and Heterakis spp. eggs would enable differential diagnosis of the individual infections in the future. 相似文献
9.
Yoon MJ Boime I Colgin M Niswender KD King SS Alvarenga M Jablonka-Shariff A Pearl CA Roser JF 《Domestic animal endocrinology》2007,33(4):470-479
The objectives of this study were to determine the efficacy of recombinant equine luteinizing hormone (reLH) in shortening the time to ovulation in cycling mares and to determine the effects of treatment on endogenous hormones and inter-ovulatory intervals. In study 1, mares of light horse breeds (3–20 years) were treated with either a vehicle, various doses of reLH, or human chorionic gonadotropin (hCG). Cycling mares were examined by palpation and ultrasound per rectum daily or every 12 h from the time of treatment to ovulation. In studies 2 and 3, jugular blood samples were collected daily or every 12 h from the time of treatment to ovulation for analysis of LH, follicle stimulating hormone (FSH), estradiol-17β (E2), and progesterone (P4) by radioimmunoassays (RIA). Increasing doses of reLH (0.3, 0.6, 0.75, and 0.9 mg) showed increasing effectiveness at inducing ovulation within 48 h of treatment. Treatments with the 0.75 and 0.9 mg doses of reLH resulted in 90% and 80% ovulation rates, which were similar to hCG treatment (85.7%). Except for the early rise in LH after treatment with 0.5, 0.65, and 1.0 mg of reLH, hormone profiles appeared to be similar between control and treated cycles. Inter-ovulatory intervals were similar between control and treatment cycles. In conclusion, reLH is a reliable and effective ovulatory agent that does not significantly alter endogenous hormone profiles or affect inter-ovulatory intervals. 相似文献
10.
陕西省部分小麦栽培品种高分子量麦谷蛋白亚基组成及其与品质关系 总被引:1,自引:0,他引:1
本研究以36个陕西省主要栽培品种为材料,利用SDS-PAGE方法分析了高分子量麦谷蛋白亚基组成,并对其SDS沉淀值进行了测定,分析了高分子量麦谷蛋白亚基组成与代表面包烘烤品质的SDS沉淀值间的关系.结果表明:Glu-1位点存在着广泛的等位基因变异,在所分析的36个品种中,Glu-A1位点亚基1出现频率最高,为63.9%;Glu-B1位点等位基因变异最丰富,其中亚基7 8和7 9出现频率最高,其次为亚基14 15;Glu-D1位点亚基组成以2 12为主;对各位点品质评分与SDS沉淀值的简单相关分析结果表明各位点品质评分与SDS沉淀值均存在着显著或极显著相关关系,各位点影响大小依次为Glu-D1>Glu-A1>Glu-B1;Glu-1品质评分与SDS沉淀值极显著正相关. 相似文献