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91.
Zn对细胞保护作用机理的研究   总被引:16,自引:0,他引:16  
应用扫描质子微探针和同步辐射x荧光分析技术测定了细胞中元素的分布和组成,为确定Zn是细胞结构成分提供了直接的实验依据.用上述核技术结合有关生化指标,分析测定了正常和损伤细胞(脂质过氧化损伤)中Fe,Zn和丙二醛、SH基含量变化的相互关系.实验结果表明,当细胞发生脂质过氧化损伤时,Fe含量和丙二醛含量同步增高,而Zn含量和SH基量则降低.给细胞补充Zn后,提高了细胞质膜中的Zn含量,SH基量也随之增加,同时丙二醛量降低.提示Zn保护细胞完整性的作用机理之一是控制脂质过氧化作用.Zn可保护膜蛋白的SH基,减少和阻止被Fe所催化的过氧化反应.  相似文献   
92.
江西忍冬属药用植物资源   总被引:5,自引:0,他引:5  
报道了江西忍冬属药用植物种类、地理分布、临床疗效、化学成分等有关情况,对该属资源的开发利用提出了合理建议。  相似文献   
93.
以γ射线诱发转化的大鼠胚胎细胞(REC:myc:γ33)的DNA构建粘粒基因库,用总基因库DNA转染NIH/3T3细胞,产生转化灶的DNA作二轮转染,二轮转化的NIH/3T3细胞内有大鼠REC:myc:γ33DNA中具转化活性的N-ras基因,用不对称PCR和DNA序列分析法证明,REC:myc:γ33细胞中鼠N-ras的活化是由于第61位密码子的A→G点突变.NIH/3T3转化灶中鼠N-ras也有同样点突变,但NIH/3T3细胞的内源性N-ras基因则无此突变.  相似文献   
94.
沈阳西部污灌水中有机污染物的分析刘海玲,张丽珊,姚家彪,于殿臣,朱岩,可夫,姜萍(中国科学院沈阳应用生态研究所,110015)AnalysisofOrganicPollutantsinIrrigatedsewageInWesternShenyang....  相似文献   
95.
The Ac/Ds transposon system of maize shows low activity in Arabidopsis. However, fusion of the CaMV 35S promoter to the transposase gene (35S::TPase) increases the abundance of the single Ac mRNA encoded by Ac and increases the frequency of Ds excision. In the experiments reported here it is examined whether this high excision frequency is associated with efficient re-insertion of the transposon. This was measured by using a Ds that carried a hygromycin resistance gene (HPT) and was inserted within a streptomycin resistance gene (SPT). Excision of Ds therefore gives rise to streptomycin resistance, while hygromycin resistance is associated with the presence of a transposed Ds or with retention of the element at its original location. Self-fertilisation of most individuals heterozygous for Ds and 35S::TPase produced many streptomycin-resistant (strepr) progeny, but in many of these families a small proportion of strepr seedlings were also resistant to hygromycin (hygr). Nevertheless, 70% of families tested did give rise to at least one strepr, hygr seedling, and over 90% of these individuals carried a transposed Ds. In contrast, the Ac promoter fusion to the transposase gene (Ac::TPase) produced fewer streprhygr progeny, and only 53% of these carried a transposed Ds. However, a higher proportion of the strepr seedlings were also hygr than after activation by 35S::TPase. We also examined the genotype of strepr, hygr seedlings and demonstrated that after activation by 35S::TPase many of these were homozygous for the transposed Ds, while this did not occur after activation by Ac::TPase. From these and other data we conclude that excisions driven by 35S::TPase usually occur prior to floral development, and that although a low proportion of strepr progeny plants inherit a transposed Ds, those that do can be efficiently selected with an antibiotic resistance gene contained within the element. Our data have important implications for transposon tagging strategies in transgenic plants and these are discussed.  相似文献   
96.
We investigated the polymorphic second exon of the HLA-DPB1 and HLA-DRB1 genes, using in vitro DNA amplification by polymerase chain reaction (PCR) and oligonucleotide hybridization in 136 patients with early onset pauciarticular juvenile chronic arthritis (EOPA-JCA) and 199 healthy controls. The analysis of the HLA-DRB1 system revealed that most of the DRB1 alleles are not indifferent with respect to susceptibility to EOPA-JCA. There is a hierarchy of susceptible (DRB1*08, DR5), permissive (DRB1*01), moderately protective (DR2, DRB1*04), and protective (DRB1*07) alleles. In contrast, no hierarchy could be shown for the HLA-DPB1 system. DPB1*0201 was found to be susceptible. The relatively frequent alleles DPB1*0402 and DPB1*0401 seem to be indifferent. The associations with DPB1*0201, DR5, and DRB1*08 are independent of each other: that is to say they, are not brought about by linkage disequilibrium. The susceptible alleles DPB1*0201 and DR5 show evidence for interaction in the pathogenesis of EOPA-JCA. Interaction seems likely between DPB1*0201 and DRB1*08, DR5 and DRB1*08, or between DR6 and DRB1*08. The strongest interaction exists between DPB1*0201 and a common DQ factor associated with both DR5 and DRB1*08. Finally, we observed a hierarchy among the various marker combinations, where the risk of developing EOPA-JCA increases with the number of associated markers present in an individual.This work was supported by SFB217.The data presented here are part of the doctoral thesis of C. Paul.  相似文献   
97.
We have investigated the DNA polymorphism for the DQA1 promoter region (QAP) and HLA-class II DRB1, DQA1, and DQB1 genes in 178 central European patients with Systemic lupus erythematosus (SLE) using polymerase chain reaction and Dig-ddUTP labeled oligonucleotides. Increased frequencies of DRB1*02 and *03 are confirmed by DNA typing. In addition, the frequencies of DQA1*0501, *0102 and DQB1*0201, *0602 alleles are increased in the patients as compared to controls. The strongest association to SLE is found with DRB1*03 and DQB1*0201 alleles (p<10–7, p corr. <10–5 and p<10–6, p corr. <10–4, respectively). By investigating the DQA1 promoter region in the SLE patients we have detected nine different QAP variants. Increased frequencies of QAP1.2 and QAP4.1 are observed in patients as compared to controls (p <0.05, p corr. = n. s.). Analysis of linkage disquilibria demonstrates a very strong association between QAP variants and DQA1, DRB1 alleles. Certain QAP variants are completely associated with DQA1 and DRB1 alleles, whereas others can combine with different DQA1 and DRB1 alleles. All DRB1*02-positive patients and controls carry QAP1.2, and all DRB1*03-positive patients and controls carry QAP4.1. Conversely, the QAP1.2 variant appears only in DRB1*02 haplotypes, while the QAP4.1 variant can be observed in DRB1*03, *11, and *1303 haplotypes. Based on the strong linkage disequilibria between DRB1-DQA1-DQB1 genes and between DRB1-QAP-DQA1, we have deduced the four-point haplotypes for DRB1-QAP-DQA1-DQB1 in patients and controls. Two haplotypes DRB1*02-QAP1.2-DQA1*0102-DQB1*0602-and DRB1*03-QAP4.1-DQA1*0501-DQB1*0201 are significantly increased in patient as compared to controls (p<0.01, p corr. = n.s., RR = 1.8 and p <10–7, p corr. <10–5, RR = 3.1, respectively). The analysis of relative risks attributed to the various alleles of QAP, DQA1, and DQB1 as well as the investigation of the deduced DRB1-QAP-DQA1-DQB1 haplotypes leads to the conclusion that QAP4.1 and DQA1*0501 on the DR3 haplotypes are probably not involved in SLE susceptibility. There is no evidence for the involvement of DQ2 / dimers coded in transposition. Thus, susceptibility to SLE is on the DR3 haplotype most probably localized at DRB1 or telomeric of DRB1, while for the DR2 haplotype such orientation cannot be given. SLE study group members: M. Baur, A. Corvetta, H. Ehrfeld, J. Frey, J. R. Kalden, F. Krapf, B. Lang, G. G. Lange, K. Pirner, C. Rittner, E. Röther, P. Schneider, H. P. Seelig, S. Seuchter, W. Stangel, C. Specker, P. Späth, H. Deicher. Correspondence to: Z. Yao.  相似文献   
98.
Root, hypocotyl and cotyledon explants of Sesbania bispinosa, Sesbania cannabina, Sesbania formosa, and Sesbania sesban were cultured on Murashige and Skoog medium with benzyladenine (BA; 2.22, 4.44, 8.88 M) in combination with 2,4-dichlorophenoxyacetic acid (2,4-d; 2.26, 4.52, 9.05 M), indolebutyric acid (IBA; 0.25, 0.49, 4.92 M) or naphthaleneacetic acid (NAA; 2.69, 5.37, 10.74 M). Although all explant types developed some callus, callus occurred earliest and continued to grow fastest with hypocotyls. Media including 2.4-d or NAA gave the fastest growing callus. Callus was subcultured up to 10 times at 20-day intervals and retained a rapid growth rate. Shoots regenerated readily from both hypocotyls or cotyledons but not from roots. Shoot organogenesis was most frequent with IBA (0.25–4.92 M) in combination with BA (4.44–8.88 M) and did not occur with 2,4-d. With each species at least one medium induced shoot differentiation from more than 50 percent of the callus pieces. With one exception, media containing IBA that induced shoot organogenesis on explants also did so in callus, but media containing NAA, even when effective with explants, did not cause differentiation of callus. Shoots that differentiated were excised and cultured on MS medium without growth regulators or with IBA (2.46, 4.92, 9.84 M). Roots developed after 3–8 days on an appropriate rooting medium, often without IBA. Rooted plantlets were transplanted to pots in a greenhouse and developed into normal plants. Suitable media and protocols for initiating and subculturing callus and regenerating whole plants in vitro from callus and explants have thus been established for four species of Sesbania.  相似文献   
99.
RGDS肽对大鼠主动脉球囊内膜剥脱后血管壁增殖的影响   总被引:1,自引:0,他引:1  
在大鼠主动脉球囊内膜剥脱术后血管壁细胞过度增殖模型上,用合成的血小板膜纤维蛋白原受体(glycoproteinⅡb/Ⅲacomplex,GPⅡb/Ⅲa)拮抗剂RGDS(Arg-Gly-Asp-Ser,50μmol·kg-1·d-1)治疗可有效地抑制损伤血管壁的细胞计数增加和内膜增厚以及血管平滑肌细胞增殖,显著降低其血管组织3H-TdR和3H-Leu的参入增加程度。实验结果提示RGDS肽作为血管成型术的辅佐剂,对于防治血管再狭窄可能具有潜在的临床应用前景。  相似文献   
100.
本研究以清栓酶、川芎嗪为抗栓剂加入葡萄糖中,经紫外线氧透照仪照射后输入静脉,治疗缺血性脑血管病,并与单用抗栓剂组作对照,进行疗效对比,结果发现抗栓剂加紫外线氧透照组的显效率显著高于对照组(P<0.05)。说明经紫外线氧透照后的葡萄糖作为载体,有分解出氧原子以提高血氧含量改善脑组织的缺氧状态,并有激活清栓酶和川芎嗪的效应。  相似文献   
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