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991.
J. T. M. van der Meer W. van Vianen E. Hu W. B. van Leeuwen H. A. Valkenburg J. Thompson M. F. Michel 《European journal of clinical microbiology & infectious diseases》1991,10(9):728-734
During a two-year period data were collected nationwide in The Netherlands on 438 episodes of bacterial endocarditis (BE) in 432 patients. Of the strains isolated in these patients 419 were available for analysis. Of these, 326 were isolated in native valve endocarditis (NVE) and 93 in prosthetic valve endocarditis (PVE). Viridans streptococci, staphylococci and enterococci together constituted 87 % of the isolates. More than 46 % of the viridans streptococci consisted ofStreptococcus sanguis. Enterococus faecalis andStaphylococcus aureus were the predominant species in the late form of PVE. The majority of the viridans streptococci and haemolytic streptococci were highly susceptible to penicillin. Five of 35 strains of coagulase negative staphylococci were resistant to methicillin. Eleven percent of a random sample of the streptococci collected were tolerant to penicillin. After repeated exposure to a concentration gradient of an appropriate -lactam antibiotic, this figure increased to 49 %. Of the staphylococci, 5–6 % of the strains were tolerant before induction and 16–20 % after induction. Of theEnterococcus strains (n=40), 12.5 % showed high-level resistance to one or more aminoglycoside. 相似文献
992.
993.
Jin Y Kim HP Ifedigbo E Lau LF Choi AM 《American journal of respiratory cell and molecular biology》2005,33(3):297-302
We have used gene expression profiling approaches to identify new molecular targets in various models of lung injury and human lung diseases. Among the many genes that are significantly induced in these studies, cysteine-rich61 (Cyr61) consistently ranks as one of the most significant genes. Here, we use the well-established model of hyperoxia to better understand the function of Cyr61 in acute lung injury. Cyr61, a stress-related immediate-early response gene, has known diverse functions involving angiogenesis, tumorigenesis, and wound repair. It belongs to the newly discovered "CCN" family containing six growth and regulatory factors. We showed that hyperoxia induces Cyr61 expression in a variety of pulmonary cells and in lung tissue in vivo. Loss of function studies, by suppressing Cyr61 expression by siRNA, accelerated lung epithelial cell death after hyperoxia. Gain of function studies, by overexpressing Cyr61, significantly conferred increased resistance to hyperoxia-induced cell death. Moreover, cells overexpressing Cyr61 induce Akt activation. Inhibition of Akt by siRNA abrogated the protective effects of Cyr61-overexpressing cells in response to hyperoxia. Taken together, our data demonstrate that Cyr61 expression provides cytoprotection in hyperoxia-induced pulmonary epithelial cell death and that this effect was in part mediated via the Akt signaling pathway. 相似文献
994.
995.
The hepatitis B virus (HBV) genome is known to contain four conserved and overlapped open reading frames (ORFs) encoding the viral core, polymerase (P), surface (S), and X proteins. Whether HBV encodes other proteins has long been a major interest in the field. Using (32)P-labeling of an introduced protein kinase A site attached to the N- or C-terminus of the HBV polymerase gene, a 43-kDa P-S fusion protein was detected in cell lysate, secreted virions, and 22-nm subviral particles. Immunobiochemical studies showed that the 43-kDa protein contains the epitopes of the N-terminus of polymerase and most parts of the surface proteins. This 43-kDa protein was shown to be a glycoprotein, similar to the surface protein. RT-PCR and sequence analyses identified a spliced mRNA which was derived from pregenomic RNA with a deletion of 454 nucleotides (nt) from nt 2447 to 2902. This splice event creates a P-S fusion ORF. This finding is consistent with the result obtained from an immunobiochemical study. Mutations at the splice donor or acceptor site on the HBV genome abrogated the production of the 43-kDa protein. These mutants had no effect on viral replication in transfected HuH-7 cells. However, this P-S fusion protein is able to substitute for the LS protein in virion maturation. On the basis of these results, we conclude that the 43-kDa protein is a polymerase-surface fusion protein encoded by a spliced RNA. Similar to the LS protein, the 43-kDa P-S fusion protein is a structural protein of HBV and might play a role in the HBV life cycle. 相似文献
996.
hTRT催化功能区基因克隆及其在肿瘤中的表达 总被引:19,自引:2,他引:19
目的 研究端粒酶蛋白hTRT基因在肿瘤中的表达及其意义。方法 用RT-PCR法检查Hela细胞与PG细胞的hTRT表达水平,将Hela细胞的hTRT催化功能克隆,并进行测序比较,应用原位杂交技术对肿瘤组织中的hTRT和hTR(端粒酶RNA组分)基因进行检测。结果 Hela细胞与PG细胞均有hTRT表达,Hela细胞hTRT催化功能区cDNA序列与文献报道一致,原位杂交结果显示hTRT与hTR的协同 相似文献
997.
Min-Seok Rha Hye Won Jeong Jae-Hoon Ko Seong Jin Choi In-Ho Seo Jeong Seok Lee Moa Sa A Reum Kim Eun-Jeong Joo Jin Young Ahn Jung Ho Kim Kyoung-Ho Song Eu Suk Kim Dong Hyun Oh Mi Young Ahn Hee Kyoung Choi Ji Hoon Jeon Jae-Phil Choi Eui-Cheol Shin 《Immunity》2021,54(1):44-52.e3
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998.
999.
K N Tsiquaye B Portmann G Tovey H Kessler S Hu X Z Lu A J Zuckerman J Craske R Williams 《Journal of medical virology》1983,11(3):179-189
There are reports in the literature that infection with hepatitis A virus in hepatitis B carriers can result in resolution of the carrier state. In an attempt to induce clearance of the carrier state of hepatitis B virus in two persistently infected chimpanzees, the chimpanzees were infused with documented non-A, non-B infectious material. Biochemical and histopathological evidence of hepatitis was accompanied by the unique abnormalities of endoplasmic reticulum associated with non-A, non-B hepatitis in the chimpanzees. Elevation of alanine aminotransferase was accompanied by fourfold reduction in one chimpanzee and sixfold reduction in the other in the plasma levels of HBV-associated DNA polymerase activity and simultaneously by twofold reduction in the concentration of hepatitis B surface antigen in both chimpanzees. A mediator may account for these changes in markers of hepatitis B virus infection, and this mechanism may also explain the occurrence of spontaneous regression in some persistently infected carriers. The significance of transient red cell anaemia in non-A, non-B hepatitis, which was observed in one of the chimpanzees, is yet to be established. 相似文献
1000.
研究生物工程活性角膜的生物相容性,为进一步临床应用提供理论基础。猪角膜基质脱细胞并去除免疫源性物质形成网状半透明生物材料,将培养的角膜基质细胞与生物材料复合构建生物工程活性角膜基质。对复合物进行倒置显微镜和扫描电镜检测细胞附着情况及材料的细胞相容性;将活性角膜基质移植入新西兰兔角膜囊袋内.细胞用BrdU标记检测在体内移植过程中的存活及转归,不同时间观察角膜的生物相容性及改建情况。结果显示脱细胞基质材料的细胞相容性较好,细胞种植后可存活、黏附并增殖;移植区细胞可有BrdU阳性着色,4周后角膜开始透明,8周后角膜改建基本完成。 相似文献