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排序方式: 共有178条查询结果,搜索用时 15 毫秒
1.
北京鸭乳酸脱氢酶同工酶的研究 Ⅰ.薄层等电聚焦电泳分离北京鸭LDH同工酶 总被引:6,自引:0,他引:6
采用薄层等电聚焦电泳方法,把北京鸭乳酸脱氧酶同工酶区分为11条电泳区带,发现它们是一组等电点十分邻近的、范围在pH 6.0至8.0的中性蛋白质。 相似文献
2.
乳酸脱氢酶同工酶基因在冬眠黄鼠中的表达 总被引:3,自引:0,他引:3
本文报道了用改良z.I. Ogita的小型薄层板聚丙烯酰胺凝胶电泳,分析达乌尔黄鼠10种组织的乳酸脱氢酶(LDH)同工酶,发现了15条亚带。并用尿素抑制与热变性实验初步确定这些亚带分属于5种LDH同工酶。同时测定了LDH同工酶总活性和5种LDH的相对比例,观察和分析了黄鼠在冬眠期及其冬眠前后LDH同工酶的变化。这些变化可能反映了异温动物(冬眠动物)的LDH同工酶基因的表达有不同于恒温动物的某些特点。 相似文献
4.
摇蚊马氏管和直肠多线染色体的初步研究 总被引:1,自引:0,他引:1
从发育观点观察了摇蚊成蚊马氏管、直肠细胞中的多线染色体,特别是第Ⅳ染色体自幼虫至成蚊的动态变化过程。结果表明:染色体在个体发育中的变化是有规津的,并与细胞的分化和活动密切相关的;染色体泡和多线分化反映着细胞的结构与功能。本文特别强调了研究双翅目昆虫消化道后部器官在发生遗传学上的重要意义。 相似文献
5.
从发育的角度,观察了摇蚊消化道各区域的细胞内多线染色体,并发现马氏管和直肠两区,从幼虫经过变态到成蚊,其染色体的多线结构和区域的起泡被保持下来。这就提供一种可能对摇蚊的发育在空间和时间上的变化同染色体在结构与功能上变化的相互关系进行研究。摇蚊发育除卵外可分为幼虫(共Ⅰ—Ⅲ个分期)、蛹前期、蛹和成蚊(又分早、晚 相似文献
6.
鸭类mtDNA限制性酶切图谱的比较研究 总被引:12,自引:1,他引:12
本文报道了番鸭、建昌鸭、杂交鸭(♀建昌鸭×(?)番鸭)和北京鸭的mtDNA限制性酶切图谱。限制性内切酶HindⅢ、PsiⅠ、BamHⅠ和EcoRⅠ在番鸭mtDNA上分别有(?)、2、2和1个酶切位点。建昌鸭、杂交鸭和北京鸭的mtDNA限制性酶切图谱完全一致。以上4种内切酶在这3种鸭子mtDNA上分别有5、4、2和1个位点。比较研究4种限制性图谱,我们得到三点结论:(1)鸭类mtDN种间差异程度很高;(2)家鸭很可能不存在mtDNA种内异质现象;(3)鸭类mtDNA为母性遗传。 相似文献
7.
Chen Y Ip SP Ko KM Poon TC Ng EW Lai PB Mao QQ Xian YF Che CT 《Journal of proteome research》2011,10(1):299-304
To identify key proteins involved in the hepatoprotection afforded by schisandrin B (Sch B), we used a proteomic approach to screen proteins that were specifically regulated by Sch B in mouse livers and to investigate the role of the proteins in hepatoprotection. Thirteen proteins were specifically activated or suppressed by Sch B treatment. Among the 13 proteins, Raf kinase inhibitor protein (RKIP) was postulated to be the key regulator involved in the development of hepatotoxin-induced cellular damage. The results indicated that the downregulation of RKIP by antisense RKIP vector transfection led to the activation of the Raf-1/MEK/ERK signaling pathway, as evidenced by increases in the level of MEK/ERK phosphorylation and the level of nuclear factor erythroid 2-related factor 2 in the nucleus. The signaling effect produced by RKIP downregulation resembled that triggered by Sch B, wherein both treatments resulted in a decrease in the extent of carbon tetrachloride-induced apoptotic cell death in AML12 hepatocytes. Overexpression of RKIP by the sense RKIP transfection vector or the inhibition of MEK kinase by PD98059 was able to abrogate the cytoprotective effect of Sch B in the hepatocytes. The results indicate that Sch B triggers the Raf/MEK/ERK signaling pathway, presumably by downregulating RKIP, thereby protecting against carbon tetrachloride-induced cytotoxicity. 相似文献
8.
Teleconnection between the early immigration of brown planthopper (BPH) and El Nino/Southern Oscillation (ENSO) indices from January of two years previously to the current June was investigated to make long-term forecast. The teleconnection results were as follows: ENSO indices which were significantly correlated with the early immigration of BPH were primarily sea surface temperature anomalies (SSTA) in N3, N4 and N3.4 regions, accounting for 71.8% of the total. Significant ENSO indices from two years and one year before the immigration events had a proportion of about 84%, while those in the current year only accounted for 16.7%. There was significantly negative correlation between the early immigration of BPH and SSTA in each Nino region from two years before to the previous spring, whereas there was significantly positive correlation between these two factors during the period from the previous winter to the current spring. The significant correlation between the early immigration of BPH and SSTA in each Nino region in the last summer and autumn did not show any obvious tendencies. The relationship between the southern oscillation index (SOI) and the early immigration of BPH was opposite to that between the immigration and SSTA in each Nino region. The above mentioned significant ENSO indices were used as key factors to build forecasting models for the early immigration of BPH by step-wise multiple linear regression analysis. Finally, 12 integrated forecasting models were obtained, which could make predictions 3–27 months ahead and had a predictive accuracy of 88.9%. 相似文献
9.
Xing-Bao Feng Zi-Wen Zheng Xian Zhang Jun Gu Qi-Li Feng Li-Hua Huang 《Insect Science》2019,26(5):821-830
Silkworm mutants are valuable resources for both transgenic breeding and gene discovery. PiggyBac-based random insertional mutagenesis has been widely used in gene functional studies. In order to discover genes involved in silk synthesis, a piggyBac-based random insertional library was constructed using Bombyx mori, and the mutants with abnormal cocoon were particularly screened. By this means, a “thin cocoon” mutant was identified. This mutant revealed thinner cocoon shell and shorter posterior silk gland (PSG) compared with the wild type. The messenger RNA (mRNA) levels of all the three fibroin genes, including Fib-H, Fib-L and P25, were significantly down-regulated in the PSG of mutants. Four piggyBac insertion sites were identified in Aquaporin (AQP), Longitudinals lacking protein-like {Lola), Glutamyl aminopeptidase-like (GluAP) and Loc101744460. The mRNA levels of all the four genes were significantly altered in the silk gland of mutants. In particular, the mRNA amount of AQP, a gene responsible for the regulation of osmotic pressure, decreased dramatically immediately prior to the spinning stage in the anterior silk gland of mutants. The identification of the genes disrupted in the “thin cocoon” mutant in this study provided useful information for understanding silk production and transgenic breeding of silkworms in the future. 相似文献
10.
The major aim of the project was to develop the virus-like particles (VLPs) displaying single or multi-epitope of hepatocellular carcinomas (HCC) in Escherichia coli and to evaluate the effect on inducing Ag-specific CD8(+) T cell response and antitumor efficacy as candidate vaccines. To this end, hepatitis B virus core (HBc) particles were used as a carrier of HCC epitopes. Four HCC epitopes MAGE-1(278-286aa), MAGE-3(271-279aa), AFP1 (158-166aa) or AFP2 (542-550aa) were fused to the 3' terminus of the truncated HBV core gene, respectively, or conjunctively. Not all recombinant plasmids led to expression of chimeric proteins in expression strain E. coli BL21 (DE3), but chimeric proteins which are expressed in inclusion bodies resulted in the formation of complete "mature" VLPs. E. coli-derived truncated HBc(1-144) chimeric protein self-assembled into VLPs that both morphologically and physically are similar to the wild-type ones and they still remained activity after purification and refolding from 6M urea solution. We also showed that they could be internalized and presented by DCs in vitro. Additionally, DCs pulsed with the chimeric HBc-VLPs could induce stronger CTL activity and greater IFN-gamma secretion by responding T cells compared with peptid-pulsed DCs. In the B16-pIR-HH tumor therapy model, the growth of established tumors was significantly inhibited by immunization using VLP-pulsed DCs, resulting in significantly higher survival rate of immunized animals. Thus, the results of the current study have demonstrated the principal possibility of using VLP on the basis of HBcAg for creation of a new type of HCC-specific immunogen. 相似文献