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991.
乐至黑山羊PRLR基因外显子10多态性与产羔数的关系研究 总被引:2,自引:0,他引:2
设计2对特异性引物对乐至黑山羊PRLR基因第10外显子进行了PCR-SSCP检测,并研究该基因与产子性能的相关性。结果表明,P1引物扩增片段不存在多态性;P2引物扩增片段存在多态性,表现为AA,AB,AD和CD 4种基因型,测序结果表明,4种基因型都在该片段第89、94、146和157位存在C→T、A→C、C→G、G→C的突变;此外AA型还在61位发生C→T的突变;AD型还在175位发生A→G的突变;CD型还在24位发生T→C的突变,96位发生C→T的突变,通过统计分析发现AD型平均产羔数优于其他3种基因型,并且与AB型差异达到显著水平(P<0.05)。因此认为PRLR基因对于乐至黑山羊产子性能有一定的影响。 相似文献
992.
重组干扰素γ的中间试制 总被引:6,自引:0,他引:6
用带有表达质粒PBV220(含有γ干扰素基因)的大肠杆菌DH5α株进行发酵培养,3批中试的菌产量平均为14.1克/L,γ干扰素的表达量平均为1.02±10^9IU/L,收集的菌体经高压匀质破菌后收集包涵体,用7mol/L盐酸胍提取干扰素,此过程中去除78.4%菌体蛋白,而干扰素活性仅损失10.41%,粗制干扰素经复性可使干扰素活性提高405%,比活也有明显提高,3批平均为1.76×10^7IU/m 相似文献
993.
总结和分析在心脏手术中进行自身血回收的经验。1999年1月-2000年3月,上海市胸科医院共进行自身血回收55例,其中男性27例,女性25例。年龄范围19-71岁,体表面积1.3-2.2m^2。本院应用的是意大利dideco公司生产的自身血回收机及其管道,不仅回收手术野血,而且回收体外循环管道内的残余血液。结果:55例患者均康复。自身血回收组患者的术后用血量和ICU时间与对照组相比,均显著降低(P<0.05)。讨论:自身血回收技术除可减少患者术后用血量和ICU时间与对照组相比,均显著降低(P<0.05)。讨论:自身回收技术除要减少患者术后用血、缓解血源紧张、避免血源性疾病外,还可提供以下有利条件:①为稀有血型患者提供手术保障;②可提供手术中发生意义大出血时的应急处理手段;③为外地患者就医和手术提供方便,并能减轻经济负担。 相似文献
994.
Spred2 Modulates the Erythroid Differentiation Induced by Imatinib in Chronic Myeloid Leukemia Cells
Yuefeng Yang Xiaoyun Liu Fengjun Xiao Shuya Xue Qinqin Xu Yue Yin Huiyan Sun Jie Xu Hengxiang Wang Qunwei Zhang Hua Wang Lisheng Wang 《PloS one》2015,10(2)
Differentiation induction is currently considered as an alternative strategy for treating chronic myelogenous leukemia (CML). Our previous work has demonstrated that Sprouty-related EVH1 domainprotein2 (Spred2) was involved in imatinib mediated cytotoxicity in CML cells. However, its roles in growth and lineage differentiation of CML cells remain unknown. In this study, we found that CML CD34+ cells expressed lower level of Spred2 compared with normal hematopoietic progenitor cells, and adenovirus mediated restoration of Spred2 promoted the erythroid differentiation of CML cells. Imatinib could induce Spred2 expression and enhance erythroid differentiation in K562 cells. However, the imatinib induced erythroid differentiation could be blocked by Spred2 silence using lentiviral vector PLKO.1-shSpred2. Spred2 interference activated phosphorylated-ERK (p-ERK) and inhibited erythroid differentiation, while ERK inhibitor, PD98059, could restore the erythroid differentiation, suggesting Spred2 regulated the erythroid differentiation partly through ERK signaling. Furthermore, Spred2 interference partly restored p-ERK level leading to inhibition of erythroid differentiation in imatinib treated K562 cells. In conclusion, Spred2 was involved in erythroid differentiation of CML cells and participated in imatinib induced erythroid differentiation partly through ERK signaling. 相似文献
995.
Escherichia coli, Salmonella spp. and Staphylococcus aureus are frequent co-visitors of contaminated foods to cause food-borne diseases. To achieve rapid detection of three organisms by multiplex PCR, a selective co-enrichment broth was considered to design using response surface methodology (RSM) in this work. NaCl, LiCl and KSCN as selective bacterial inhibitors were selected to optimize their concentrations for a matched composition of bacterial biomass with uniform amplification of three targets. Central composite design was employed to collect the data and fit the responses. Three quadratic polynomial models were derived by computer simulation. A statistical analysis was carried out to explore the effects of the variables on the composition of bacterial biomass and PCR amplification yields. In the end, a novel broth (ESS-3 broth) of NaCl 1.60%, LiCl 0.70%, KSCN 0.10% was formulated to allow co-enrichment of the target pathogens and suppress growth of some non-target pathogens. The simultaneous detection of E. coli, Salmonella spp. and S. aureus was developed on a rapid, convenient and sensitive method consisting of selective co-enrichment in ESS-3 broth, DNA extraction with the boiling method and robust test by multiplex PCR. Our work provided broader application of RSM for the simultaneous detection of other combinations of multiple pathogens. 相似文献
996.
997.
A method for predicting type I and II β-turns using nuclear magnetic resonance (NMR) chemical shifts is proposed. Isolated β-turn chemical-shift data were collected from 1,798 protein chains. One-dimensional statistical analyses on chemical-shift data of three classes β-turn (type I, II, and VIII) showed different distributions at four positions, (i) to (i + 3). Considering the central two residues of type I β-turns, the mean values of Cο, Cα, HN, and NH chemical shifts were generally (i + 1) > (i + 2). The mean values of Cβ and Hα chemical shifts were (i + 1) < (i + 2). The distributions of the central two residues in type II and VIII β-turns were also distinguishable by trends of chemical shift values. Two-dimensional cluster analyses on chemical-shift data show positional distributions more clearly. Based on these propensities of chemical shift classified as a function of position, rules were derived using scoring matrices for four consecutive residues to predict type I and II β-turns. The proposed method achieves an overall prediction accuracy of 83.2 and 84.2 % with the Matthews correlation coefficient values of 0.317 and 0.632 for type I and II β-turns, indicating that its higher accuracy for type II turn prediction. The results show that it is feasible to use NMR chemical shifts to predict the β-turn types in proteins. The proposed method can be incorporated into other chemical-shift based protein secondary structure prediction methods. 相似文献
998.
999.
1000.
Hisashi Mizutani Hideaki Sugawara Ashley M. Buckle Takeshi Sangawa Ken-ichi Miyazono Jun Ohtsuka Koji Nagata Tomoki Shojima Shohei Nosaki Yuqun Xu Delong Wang Xiao Hu Masaru Tanokura Kei Yura 《BMC structural biology》2017,17(1):4