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61.
62.
细胞因子Midkine(简称MK)是新发现的一类肝素结合因子家族中的一员。1988年,Kadamatsu等利用差异杂交法在经维甲酸诱导分化的小鼠畸胎瘤细胞株HM-1中首先克隆到小鼠MK基因。人MK基因则最早是从λgt10人胚肾(20-24周)cDNA库和EMBL-3人胎盘基因组库获得。成熟  相似文献   
63.
The human phosphoglycerate kinase (PGK1) gene is located within Xqll-Xql3 and is closely linked to the androgen receptor gene within a region implicated in a number of X-chromosome-linked urologic disorders. A polymorphism of a TATC short tandem repeat (STR) is present downstream from the PGK1 3' nuclease-sensitive site. We present the PGK1 flanking STR sequence and population genetic data for 190 Japanese males and 83 Japanese females. Ten STR alleles and 29 genotypes were identified in the population. Five alleles--*10, *11, *12, *13, and *14--were common in the Japanese with frequencies greater than 10%. No significant deviations from Hardy-Weinberg equilibrium were established. The power of discrimination was 0.993 for females and 0.819 for males; heterozygosity was 0.759 for females; and the polymorphic information content was 0.936. These data indicate that this STR locus shows a high degree of polymorphism in this Japanese population and may prove to be a useful genetic marker in forensic medicine, in determining the clonality of neoplasms, and potentially in studying predisposition to prostate cancer and other urologic diseases.  相似文献   
64.
不动杆菌CGMCC 0789的海藻酸凝胶包埋固定化细胞可高对映选择性地水解拆分环戊烯酮(简称HMPC)乙酸酯.异丙醇对固定化细胞的活力和对映选择性有显著提高.反应体系中异丙醇浓度为10%(体积分数,全文同)时,固定化细胞的活力最高,为6.22 mmol/(L·min·g)细胞干重,是未添加异丙醇的对照组的150%.此时E值为94±6,是对照组的1.7倍.以光学纯环戊烯酮乙酸酯为底物,对部分纯化的不动杆菌酯酶进行了动力学考察.通过动力学参数推算,10%异丙醇存在时,酯酶的对映选择性(E值)为36.5,是空白的2.3倍.10%异丙醇存在下,固定化细胞仍具有良好的操作稳定性.连续反应10批,固定化细胞的活力保持良好.  相似文献   
65.
66.
炎症小体是存在于胞浆的大分子多蛋白复合物,在感染或应激状态下被激活,并触发IL-1β和IL-18等促炎细胞因子的释放,诱导细胞焦亡,从而参与先天免疫防御。NLRP3识别病毒复制过程中产生的各种病原体相关分子模式(PAMP)和危险相关分子模式(DAMP),启动NLRP3炎症小体依赖的抗病毒免疫反应。但是,有些病毒也进化出复杂的策略而靶向炎症小体,以逃避天然免疫监视。本综述讨论了病毒感染过程对NLRP3炎症小体的活化、组装和效应的影响。  相似文献   
67.
A series of pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base moiety were synthesized, characterised, and evaluated for their activity against tobacco mosaic virus (TMV). Biological assays indicated that several of the derivatives exhibited significant activity against TMV. In particularly, compounds 5y and 5aa displayed excellent inactivating activity against TMV, with half maximal effective concentration (EC50) values of 70.3 and 53.65?μg/mL, respectively, which were much better than that of ribavirin (150.45?μg/mL), and 5aa was superior to ningnanmycin (EC50?=?55.35?μg/mL). Interactions of compounds 5y and 5aa with TMV coat protein (TMV-CP) were investigated using microscale thermophoresis and molecular docking. Compounds 5y and 5aa displayed strong binding capability to TMV-CP with dissociation constant (Kd) values of 22.6 and 9.8?μM, respectively. These findings indicate that pyrazolo[3,4-d]pyrimidine derivatives containing a Schiff base may be potential antiviral agents.  相似文献   
68.
The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldo’s method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application.  相似文献   
69.
Mao JW  Wang LW  Jacob T  Sun XR  Li H  Zhu LY  Li P  Zhong P  Nie SH  Chen LX 《Cell research》2005,15(5):371-378
The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5‘-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.  相似文献   
70.
目的探讨气道食道双管喉罩在急诊危重患者紧急人工气道建立中的应用价值。方法对2014年1月~2016年12月我院急诊科院前和院内抢救需行紧急气管插管但经评估后存在困难或操作后失败的危重症患者76例,根据其最终建立的人工气道方式分为继续设法气管插管组(A组)36例和改用气道食道双管喉罩组(B组)40例,观察比较两组患者建立气道成功率和建立气道所用时间。结果 B组通气成功率显著高于A组的插管成功率,两组比较差异有统计学意义(P0.05);B组建立气道所用时间明显少于A组,两组比较差异有统计学意义(P0.05)。结论气道食道双管喉罩可作为急诊危重症患者在气管插管术困难或失败后首选的替代、次选方案,具有操作简便,成功率高,并发症发生率低等优点,值得临床推广应用。  相似文献   
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