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111.
选择HSD11B1和MyoG2个基因作为影响妊娠期长短的候选基因。在7个中外猪群体中采用PCR-RFLP技术研究了HSD11B1和MyoG2个基因多态性与妊娠期长短的关系。HSD11B1基因的PCR-Bsh1236Ⅰ-RFLP分析结果表明:清平猪、新清平猪母系、大白猪、长白猪、杜洛克猪、中国瘦肉猪新品系DIV1和DIV2系猪群中A等位基因的频率分别为0.538、0.752、0.522、0.941、1.000、0.889和0.594;除DIV2外,HSD11B1不同基因型与妊娠期长短无显著关系(P〉0.05)。MyoG基因的PCR-MspⅠ-RFLP分析结果表明:清平猪、新清平猪母系、大白猪、长白猪、杜洛克猪、中国瘦肉猪新品系DIV1和DIV2系猪群中M等位基因的频率分别为1.000、0.534、0.370、0.115、0.094、0.382和0.243;清平猪中只存在MM基因型,其他群体中3种基因型皆有分布;新清平猪母系MM比NN基因型母猪妊娠期要短,且在经产长白猪中差异极显著(P〈0.01)。 相似文献
112.
Forsyth L.M.G. Jackson L.A. Wilkie G. Sanderson A. Brown C.G.D. Preston P.M. 《Veterinary research communications》1997,21(4):249-263
Forsyth, L.M.G., Jackson, L.A., Wilkie, G., Sanderson, A., Brown, C.G.D. and Preston, P.M., 1997. Bovine cells infected in vivo with Theileria annulata express CD11b, the C3bi complement receptor. Veterinary Research Communications, 21 (4), 249-263Bovine cells from cattle infected with Theileria annulata were phenotyped with monoclonal antibodies recognizing bovine leukocyte antigens. Macroschizont-infected, transformed cell lines prepared from peripheral blood mononuclear cells of cattle, infected with sporozoites, were assessed by flow cytometry; parasitized cells in tissues from infected cattle were examined by immunocytochemical techniques. Co-expression of markers for different cell lineages by the cell lines precluded a definite conclusion as to their phenotypic origins. For, while the pattern of leukocyte antigens expressed by these in vivo-derived schizont-infected cells, which included CD11b, was indicative of a myeloid origin, the possibility that they were NK cells could not be excluded. The monoclonal antibody (MAb) IL-A15, which recognizes CD11b, reacted with a high proportion of parasitized cells in sections of tissues from infected cattle at all stages of acute disease. Mononuclear cells infected with parasites at all stages of differentiation, from macroschizont to microschizont, expressed CD11b. Such parasitized cells occurred throughout the lymphoid tissues, being found in the thymus, spleen and lymph nodes, particularly the prescapular node draining the site of infection, the hepatic, mesenteric and precrural nodes, as well as in the reticulo-endothelial tissue of the liver, kidney, lung, abomasum, adrenal and pituitary glands. These observations provided the first evidence for a myeloid origin for the parasitized T. annulata cells found in infected bovine tissues and blood and suggested a mechanism whereby schizonts could transfer from cell to cell during mechanical infection with schizont-infected cells. 相似文献
113.
Conidial germination and differentiation, the so‐called prepenetration processes, of the barley powdery mildew fungus (Blumeria graminis f.sp. hordei) are triggered in vitro by very‐long‐chain aldehydes, minor constituents of barley leaf wax. However, until now it has not been demonstrated that these cuticle‐derived molecules also play a significant role in the initiation and promotion of the fungal prepenetration processes in vivo, on the surface of a living plant leaf. In the maize (Zea mays) wax mutant glossy11, which is completely devoid of cuticular very‐long‐chain aldehydes, germination and appressorial differentiation of B. graminis were strongly impeded. Spraying the mutant leaf surface with aldehyde‐containing wild‐type wax or pure n‐hexacosanal (C26‐aldehyde) fully restored fungal prepenetration, whereas maize wild‐type leaf surfaces coated with n‐docosanoic acid exhibited reduced conidial germination rates of 23%, and only 5% of the conidia differentiated infection structures. In vitro studies were performed to further corroborate the extensive prevention of fungal germination and differentiation in response to artificial surfaces coated with aldehyde‐deficient maize wax. Because of its phenotype affecting the B. graminis prepenetration processes, the glossy11 mutation of maize may become a valuable molecular target and genetic tool that could provide a means of developing basal powdery mildew resistance in the globally important crops wheat and barley. 相似文献
114.
SLFN是一类干扰素诱导蛋白,还可以通过干扰素调节因子(IRF3)途径被病原体直接诱导表达。最新研究表明,SLFN11可通过抑制病毒蛋白合成,对慢病毒属的HIV-1具有明显抗病毒作用。为阐明SLFN11对马传染性贫血病毒(EIAV)的作用,本研究采用RT-PCR技术从健康马淋巴细胞中首次扩增获得SLFN11基因,构建了真核表达重组质粒pHA-eSLFN11。将其与EIAV的感染性克隆共转染HEK293T细胞,western blot检测结构蛋白的表达情况,并采用激光共聚焦试验分析SLFN11在亚细胞中的定位。研究结果显示,SLFN11能够促进EIAV结构基因(Gag)的表达,此外马源SLFN11(eSLFN11)与人源SLFN11(hSLFN11)明显定位不同。以上结果提示,eSLFN11与EIAV的作用明显区别于hSLFN11对HIV-1的限制作用,其机制有待进一步研究。 相似文献
115.
EPA/DHA对体外发酵及瘤胃液脂肪酸组成的影响 总被引:2,自引:1,他引:1
试验旨在研究日粮中添加不同水平的DHA/EPA对体外发酵和瘤胃液脂肪酸变化的影响。试验通过采用持续动态人工瘤胃装置,向发酵罐中添加EPA/DHA,连续培养7 d,分析脂肪酸组成的变化及发酵模式的改变。试验结果表明,日粮添加EPA/DHA使瘤胃液pH升高(与CK相比,Trt1和Trt2分别升高了0.11和0.35),Trt2 与CK相比差异极显著(P<0.01);与CK相比处理组3种主要挥发酸中乙酸浓度下降(P<0.01),丙酸浓度升高(P<0.01),丁酸浓度下降(P<0.01),总挥发性脂肪酸浓度与对照组相比略有下降但差异不显著(P>0.05);日粮添加EPA/DHA使瘤胃液脂肪酸成分发生改变。与CK相比处理组C18∶0含量显著下降(P<0.01); t 11 C18∶1含量显著升高(P<0.01);c-9,t-11 CLA含量显著升高(P<0.01),但是两组之间差异均不显著。因此,日粮中添加不同水平的EPA/DHA可以改变瘤胃发酵模式,影响不饱和脂肪酸瘤胃氢化过程,使脂肪酸组成发生改变,为采用新的营养措施调控反刍动物产品中CLA的含量提供理论依据。 相似文献
116.
天椒11 号是以高代株选系98L-3-9-7 为母本,以97L-9-5-2 为父本配制而成的辣椒一代杂种;
植株生长势中等,株高平均68 cm,分枝0~3 枝,叶片中等,色绿,主茎7~8 节以后着生第1花序,1~2
花,果实单生或双生,可连续结果7~8 个,果实长螺丝形,纵径23~33 cm,横径4.2~5.0 cm,果肉厚
0.35 cm。单果质量75 g,青熟果绿色,老熟果深红色,味辣,早熟,耐低温、高温性强(不易出现日灼果),
田间对病毒病、炭疽病的抗性强于对照猪大肠,每667 m2 前期产量1 600 kg 以上,总产量4 900 kg 以上,
耐贮运,适合保护地及露地栽培,特别适合习惯种植螺丝椒和猪大肠的区域种植。 相似文献
117.
基于MK7A11单片机的射频遥控控制器的设计 总被引:1,自引:0,他引:1
针对当前国内灯具等用电设备落后的控制现状,自行开发设计一款结构简单、低功耗、高抗干扰性、低成本的射频遥控开关控制系统,实现了多路灯具设备的智能无线遥控开关控制. 相似文献
118.
Competitive interactions among multiple non‐native salmonids and two populations of Atlantic salmon
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Competitive interactions with non‐native species can have negative impacts on the conservation of native species, resulting in chronic stress and reduced survival. Here, juvenile Atlantic salmon (Salmo salar) from two allopatric populations (Sebago and LaHave) that are being used for reintroduction into Lake Ontario were placed into semi‐natural stream tanks with four non‐native salmonid competitors that are established in Ontario streams: brown trout (S. trutta), rainbow trout (Oncorhynchus mykiss), Chinook salmon (O. tshawytscha) and coho salmon (O. kisutch). Brown trout and rainbow trout reduced the survival and fitness‐related traits of Atlantic salmon, whereas Chinook salmon and coho salmon had no impact on these traits. These data support theories on ecological niche overlap and link differences in observed aggression levels with competitive outcomes. Measurements of circulating hormones indicated that the Atlantic salmon were not chronically stressed nor had a change in social status at the 10‐month time point in the semi‐natural stream tanks. Additionally, the Sebago population was better able to coexist with the non‐native salmonids than the LaHave population. Certain populations of Atlantic salmon may thus be more suitable for some environments of the juvenile stream phase for the reintroduction into Lake Ontario. 相似文献
119.
120.
RT-PCR and RACE techniques were used to clone 3' end real sequence of RPL11 gene from a goat. The sequences included some non-structural protein (3D) genes, and 3D gene immediately downstream 3' non-coding region (UTR) and poly (A) tail. The results showed that the length of specific amplified fragment was 566 bp (not including polyA tail). RPL11 gene encoded 188 amino acids, amino acid sequence was conducted for homology analysis by NCBI BLAST tool. The highest homology was Mus (RPL11, mRNA homology 99%), ... 相似文献