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911.
Inhibition of reporter gene and Iridovirus-tiger frog virus in fish cell by RNA interference 总被引:5,自引:0,他引:5
We describe the specific silencing of reporter gene lacZ in FHM cells (muscle cells of fathead minnow, a fish cell line) by either expressing small hairpin RNAs (shRNAs) from plasmids or transfecting small interfering RNAs (siRNAs) transcribed in vitro. Two types of dsRNAs could inhibit reporter gene expression, and siRNAs were more effective, while both of them worked very well in HeLa cells. siRNAs were tested for silencing expression of the major capsid protein (MCP) encoded by tiger frog virus (TFV), an iridovirus causing severe disease in fish. siRNAs targeting mcp gene effectively inhibited TFV replication in fish cells as demonstrated by reduced mcp RNA level, postponed emergence of cytopathogenic effect, as well as reduced TFV titer and particles in cells. The results suggest that the siRNA method suppressed TFV efficiently in fish cells, providing a potential approach to the therapy of aquaculture viral diseases. 相似文献
912.
淋巴结原发上皮样血管内皮瘤1例及文献复习 总被引:2,自引:1,他引:2
目的 探讨淋巴结原发上皮样血管内皮瘤的诊断及鉴别诊断。方法 1例淋巴结原发上皮样血管内皮瘤进行HE切片、组织化学、免疫组化等观察,并复习文献进行讨论。结果 光镜下肿瘤细胞呈多角形或类圆形上皮样,无明显核分裂象,组织结构多种,呈单个细胞条索、实性巢状及管腔样结构排列,瘤细胞形成小的细胞内管腔,见胞质内空泡,并见红细胞,此特征为细胞原始管腔结构。玻璃样间质。网状纤维染色显示血管腔隙结构。肿瘤细胞表达Vim、CD31、FⅧRAg,少数细胞表达CD34。结论 淋巴结原发上皮样血管内皮瘤是极少见的低度恶性血管性肿瘤,可出现多种组织结构,有一定的特征性。应与转移性癌、转移性恶性黑色素瘤、上皮样血管肉瘤、上皮样血管瘤、上皮样肉瘤及硬化性上皮样纤维肉瘤等鉴别。 相似文献
913.
Osseointegration rates of porous-surfaced Ti6Al4V implants with control (unmodified sintered coatings) were compared to porous-surfaced implants modified through the addition of either an Inorganic or Organic Route-formed-Ca-P film. Implants were placed in distal femoral rabbit condyle sites and, following a 9-day healing period, implant fixation strength was evaluated using a pull-out test. Three groups of ten rabbits each were evaluated. Inorganic Route Ca-P-coated implants were compared with control implants in Group I. Organic Route Ca-P-coated implants with control implants in Group II, and Inorganic- with Organic Route-Ca-P-coated implants in Group III. Maximum pull-out force and interface stiffness were compared while selected extracted implants were examined by SEM to characterise failure surfaces. Both types of Ca-P coatings significantly enhanced the early rate of bone ingrowth and fixation as evidenced by higher pull-out force and interface stiffness compared with controls. However, there was no significant difference between Ca-P-coated implants prepared using the two different methods. The enhanced osteoconductivity observed with the Organic Route-formed films despite the absence of any obvious new surface topographic features introduced with the films suggests that the increased rate of bone ingrowth was due primarily to altered surface chemistry rather than changes in topography, at least for these sintered porous-surfaced implants. 相似文献
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目的 探讨锯叶棕果实提取物沙芭特在非细菌性前列腺炎中的效应及其机制.方法 前列腺上皮细胞RWPE-1经M1表型的单核巨噬细胞THP-1细胞上清液共培养,治疗组加用沙芭特(10μg/ml)培养,MTS检测细胞增殖,流式细胞术检测细胞凋亡,RT-PCR、ELISA及West-ern blot检测炎症、纤维化及凋亡相关的蛋白分子(IL-1β、IL-17、TNF-α、Fas、COX2、Bax、TGF-β、DDR1、α-SMA及CollagenⅠ)的表达.消痔灵前列腺注射诱导大鼠非细菌性前列腺炎模型,用von Frey纤维检测沙芭特治疗前后各组大鼠的痛觉敏感性,然后麻醉SD大鼠,腔静脉取血后摘取前列腺组织并称重,免疫组化及ELISA检测炎症因子的表达,masson染色检测纤维化.结果 沙芭特抑制RWPE-1的增殖并促进其凋亡.M1表型THP-1条件培养液能促进上皮细胞表达IL-1β、TNF-α及COX-2,沙芭特处理能抑制炎症刺激所致的炎症因子表达,Western blot检测表明沙芭特处理能抑制COX-2、DDR1、SMA及CollagenⅠ的表达,增加Fas及Cleaved-caspase 3的表达.消痔灵100μl每侧叶注射可以成功诱导前列腺炎症模型,沙芭特60mg/kg能减少大鼠前列腺组织炎症因子的表达,缩小前列腺体积,降低大鼠痛觉敏感性.结论 沙芭特能抑制前列腺上皮细胞RWPE-1的增殖并促进其凋亡,减小前列腺体积,抑制炎症因子及纤维化相关分子的表达,减轻前列腺炎症及纤维化从而起到治疗作用. 相似文献
919.
The well‐known generalized estimating equations is a very popular approach for analyzing longitudinal data. Selecting an appropriate correlation structure in the generalized estimating equations framework is a key step for estimating parameters efficiently and deriving reliable statistical inferences. We present two new criteria for selecting the best among the candidates with any arbitrary structures, even for irregularly timed measurements. The simulation results demonstrate that the new criteria perform more similarly to EAIC and EBIC as the sample size becomes large. However, their performance is much enhanced when the sample size is small and the number of measurements is large. Finally, three real datasets are used to illustrate the proposed criteria. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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