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1.
目的:探讨肿瘤坏死因子相关细胞凋亡诱导配体(TRAIL)通过死亡受体-5(DR5)途径诱导的细胞凋亡与动脉粥样硬化(AS)的关系。方法:采用球囊拉伤腹主动脉加高胆固醇饮食的实验方法,建立兔AS模型;血管超声检查明确腹主动脉斑块的形成情况,然后取静脉血和腹主动脉组织,用酶联免疫吸附试验(ELISA)检测AS组及正常组兔血清中可溶性TRAIL(sTRAIL)和可溶性DR5 (sDR5)的浓度,免疫组化染色检测AS组及正常组腹主动脉壁TRAIL和DR5的蛋白表达。并比较两组间各项参数的差异。结果:AS组兔血清中sDR5浓度显著高于正常组(P<0.05),而两组兔血清中sTRAIL浓度差异无统计学意义(P>0.05)。AS组兔腹主动脉的TRAIL、DR5蛋白表达强度显著高于正常组(P<0.05),染色呈棕褐色,粗颗粒状,群集于中膜、脂质沉积处和斑块纤维帽处,高倍镜下,棕褐色颗粒主要分布在胞浆和胞核内;正常组兔腹主动脉内膜、中膜也有少量TRAIL、DR5表达,染色呈浅棕色,颗粒细小,分布散在。结论:TRAIL通过死亡受体途径诱导的细胞凋亡对AS的发生和发展起一定的促进作用,TRAIL及其受体DR5可能是AS的重要影响因子。  相似文献
2.
Background Osteosarcoma is a common primary malignant tumor of bone with a poor prognosis due to its propensity for metastasis. The prognosis of patients is highly dependent on the presence or absence of lung metastasis and on the effectiveness of treatment against it. It has been reported that low level expression of Fas protein in human osteosarcoma cell is closely associated with lung metastasis. A large number of studies have shown that arsenic trioxide (ATO) can inhibit proliferation and induce apoptosis of many cancer cell lines; however, its effects on human osteosarcoma cells (Saos-2 cell line) remains unknown. The aim of this study was to investigate the effects of ATO on Saos-2 cells and to characterize its mechanism of Fas-expressing. Methods A group of Saos-2 cells was treated with or without 0.5, 1, 2, 4 and 8 pmol/L ATO for three successive days, and the cytotoxicity of ATO was determined by an 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Morphological changes in cells were studied by acridine orange/ethidium bromide (AO/EB) double staining. Flow cytometry (FCM) was used to assay cell DNA distribution. Another group of cells was pretreated with 10 nmol/L matrix metalloproteinase 7 (MMP-7) for 3 hours. They were then incubated with or without 2 pmol/L ATO for 24, 48 and 72 hours. Cytotoxicity, Fas protein and mRNA levels were systematically studied using MTT, Western blotting and real-time PCR, respectively. Cell proliferation, cell cycle progression and apoptosis were examined in this study. Results Proliferation of Saos-2 cells was inhibited by ATO in both a dose- and time-dependent manner. The IC50 values at 24, 48 and 72 hours were 9.30, 5.54 and 3.49 pmol/L, respectively. The survival rate of Saos-2 cells in the MMP-7 and ATO co-treated group was significantly higher than the ATO group, but it was lower than the control group. ATO induced G1 phase arrest of the cell cycle and very efficiently stimulated apoptosis in Saos-2 cells, as evidenced by flow cytometric detection of sub-G1 DNA content and AO/EB staining. Western blotting results indicated that Fas (FasL) protein expression in osteosarcoma cultures markedly increases in a time dependent manner after exposure to ATO. Compared with control, treatment with ATO 2 IJmol/L and 4 pmol/L for 48 hours, resulted in increase of Fas gene expression to 28.31% and 56.74%, respectively. Our results indicated that ATO induced-apoptosis of Saos-2 cells may be mediated through the Fas pathway. Conclusions ATO suppressed cell proliferation of Saos-2 cell in a dose- and time-dependent manner and increased Fas protein expression. However, Fas-mediated apoptosis was incompletely interrupted by MMP-7, which suggested that other molecular mechanisms may mediate this process.  相似文献
3.
目的检测不稳定性心绞痛(UA)患者外周血基质金属蛋白酶-1(MMP-1)、细胞分化抗原40配体(CD40L)、白介素-1β(IL-1β)、C-反应蛋白(CRP)水平的变化,分析MMP-1水平与CD40L及IL-1β的相关性,探讨CD40L介导MMP-1的表达与分泌在UA发病机制中所起的作用。方法选择UA患者(UA组)32例,稳定性心绞痛(SA)患者(SA组)28例及健康对照组20例,采用酶联免疫吸附法(ELISA)分别测定各组外周血可溶性CD40L、MMP-1及IL-1β的水平,采用免疫比浊法测定各组CRP的水平,分析UA组MMP-1与CD40L及IL-1β之间的相关性,分析MMP-1水平与CRP的相关性。结果UA组MMP-1、CD40L和IL-1β水平显著高于SA组和对照组(P<0.01);UA组MMP-1与CD40L水平之间呈显著正相关(r=0.486,P<0.01),MMP-1与IL-1β水平之间呈相对较弱正相关(r=0.369,P<0.05);UA组MMP-1水平与CRP之间呈正的直线相关(r=0.489,P<0.01)。结论冠状动脉粥样硬化斑块的破裂可能与CD40L介导的MMP-1表达与分泌有关。  相似文献
4.
淫羊藿对激素性股骨头坏死骨组织OPG/RANKL mRNA表达的影响   总被引:2,自引:0,他引:2  
Wang JZ  Gao HY  Wang KZ  Zhou RX  Li XD  Guo J  Lv HC 《南方医科大学学报》2011,31(10):1714-1717
目的观察糖皮质激素对大鼠股骨头骨组织中骨保护素(OPG)/核因子kappa B受体活化因子配基(RANKL)mRNA表达的影响及淫羊藿的拮抗作用,探讨淫羊藿预防激素性股骨头坏死的作用效果及其作用机制。方法健康SD大鼠48只,雌雄各半,随机分为激素组、淫羊藿组和对照组,每组16只。激素组和淫羊藿组每只给予肌肉注射醋酸泼尼松龙12.5mg/kg,2次/周,淫羊藿组同时给予淫羊藿提取液1 ml/100 g(相当于0.1 g/ml生药)灌胃,而激素组用生理盐水代替淫羊藿灌胃,1次/d;对照组用生理盐水代替激素和淫羊藿以同样方式肌注和灌胃。4周后取左侧股骨头骨组织石蜡包埋,HE染色,鉴定股骨头坏死情况;取右侧股骨头骨组织提取总RNA,采用实时定量聚合酶链反应技术检测OPG和RANKLmRNA表达水平,计算出OPG/RANKL比值。结果激素组、淫羊藿组、对照组大鼠出现股骨头坏死表现比例分别为71.43%(10/14)、26.67%(4/15)、0(0/16);激素组、淫羊藿组、对照组OPG mRNA表达分别为1.13±0.32、1.47±0.42和1.51±0.43;RANKL mRNA表达分别为2.70±1.24、1.82±0.46和1.55±0.42。激素组OPG和OPG/RANKL比值低于淫羊藿和对照组,而RANKL表达高于淫羊藿组和对照组,差异有统计学意义(P<0.05)。淫羊藿组与对照组比较,差异无统计学意义。结论淫羊藿预防激素性股骨头坏死可能与其拮抗皮质激素导致的OPG/RANKL mRNA表达异常有关。  相似文献
5.
目的 探讨肝X受体(liver X receptor,LXR)激动剂T0901317对高脂饲养ApoE基因敲除(apolipoprotein E gene knockout,ApoE-/-)小鼠在动脉粥样硬化病变形成的早期动脉壁内C-反应蛋白(CRP)和CD40配体(CD40L)表达及平滑肌细胞含量的影响.方法 8周龄雄性ApoE-/-小鼠12只,按随机数字表法分入LXR激动剂T0901317组和二甲基亚砜(DMSO)溶剂对照组,每组6只.均给予高脂饲养8周,在高脂饲养的后4周,分别给予LXR激动剂T090131720 mg·kg-1·d1-或相当剂量的DMSO腹腔注射.麻醉处死小鼠后,取小鼠主动脉,以石蜡包埋,行主动脉根部连续切片,采用免疫组化法检测主动脉壁内CRP、CD40L和平滑肌细胞α-actin的表达,以Image Pro Plus 6.0软件进行图像分析.结果 LXR激动剂组动脉壁CRP表达水平较对照组明显减少(P<0.05),LXR激动剂组动脉壁CD40L表达水平较对照组明显减少(P<0.05),动脉粥样硬化斑块内平滑肌细胞α-actin表达水平与对照组比较没有统计学差异(P>0.05).结论 LXR激动剂可能通过抑制ApoE-/-小鼠动脉壁中CRP和CD40L的表达,减轻血管壁的炎症反应,从而发挥抗动脉粥样硬化形成的作用.  相似文献
6.
TRAIL在系统性红斑狼疮发病机制中的作用及其相关性研究   总被引:2,自引:1,他引:1  
目的探索肿瘤坏死因子相关凋亡诱导配体(TRAIL)在系统性红斑狼疮(SLE)细胞凋亡、自身抗体产生和疾病活动中作用。方法60例SLE患者及20名健康对照,反转录聚合酶链反应(RT-PCR)半定量分析外周血单个核细胞(PBMC)的TRAIL mRNA表达;比色法测定PBMC内Caspase-3活性表达;酶联免疫法(ELISA)测定PBMC内核小体水平、血清中可溶性TRAIL(sTRAIL)和抗核小体抗体(AnuA)浓度。结果狼疮活动组与稳定组及健康对照组相比,TRAILmRNA平均表达水平(0.82±0.07)vs(0.77±0.06)vs(0.75±0.05)、Caspase-3活性(0.53±0.27)vs(0.39±0.23)vs(0.35±0.18)、核小体浓度(U/ml)((3.09)vs(0.53)vs(0.77)及血清sTRAIL水平(μg/L)(0.88±0.74)vs(0.58±0.32)vs(0.48±0.28),差异均有显著性(P<0.05)。SLE患者TRAILmRNA平均表达水平与sTRAIL、Caspase-3活性及Caspase-3活性与核小体水平均呈显著正相关(P<0.05)。SLE患者TRAIL mRNA表达水平与SLE疾病活动指数(SLEDAI)积分数、抗dsDNA抗体、ESR、AnuA浓度呈正相关,与淋巴细胞计数及补体C4呈负相关;sTRAIL浓度与SLEDAI积分数呈正相关,与淋巴细胞计数呈负相关。核小体浓度与SLEDAI积分数、抗dsDNA抗体、AnuA浓度均呈显著正相关,与补体C3、C4水平呈负相关。结论SLE活动患者PBMC的TRAIL表达水平及血清sTRAIL水平增高,凋亡酶Caspase-3的活性增高,可能介导PBMC异常凋亡,使核小体释放增加,自身抗体水平增加,参与疾病活动。  相似文献
7.
目的肿瘤坏死相关凋亡诱导配体(TNT-related apoptosis-inducing ligand,TRAIL)作为肿瘤细胞诱导凋亡剂,可单独或与化疗药联合作用诱导多种肿瘤细胞株凋亡。本实验观察重组人可溶性TRAIL是否可有效诱导临床白血病患者的白血病细胞凋亡,并检验化疗药Ara-C联合TRAIL对白血病细胞的杀伤作用。方法将13例原始细胞比例均>60%急性白血病患者的骨髓标本的每份分4组:对照组、TRAIL组、Ara-C组、TRAIL+Ara-C组,进行细胞培养24h后,用AnnexinⅤ及碘化丙啶染色后流式细胞仪观察细胞凋亡率。结果对照组细胞凋亡率为(10.22±7.48)%,TRAIL组为(14.61±11.95)%,Ara-C组为(15.95±11.12)%,TRAIL+Ara-C组为(22.11±15.97)%。将4组标本进行组间方差检验,对照组与TRAIL+Ara-C组比较差异有统计学意义(P=0.015<0.05)。在TRAIL组中,13例中有3例(23%)显示对TRAIL诱导的凋亡敏感(若TRAIL组细胞凋亡率高于对照组10%以上,即认为对TRAIL敏感);在TRAIL+Ara-C组中,2例原对TRAIL不敏感的标本及1例对TRAIL敏感标本在TRAIL+Ara-C联合作用下,细胞凋亡率均高于对照组20%以上。结论1)TRAIL在体外可诱导急性白血病患者的白血病细胞凋亡;2)化疗药Ara-C与TRAIL联合应用可增加白血病细胞的凋亡率,包括先前对TRAIL不敏感的白血病细胞。  相似文献
8.
目的研究急性冠脉综合征(ACS)患者易损斑块[通过血管内超声(IVUS)判定]和可溶性黏附分子CD40配体(sCD40L)及其他血管因子的定量关系以及临床意义。方法42例ACS患者,发病时取血,应用液相蛋白芯片结合流式细胞分析方法测定sCD40L及相应的炎性因子水平;常规冠状动脉造影并通过IVUS检测42个靶病变处动脉粥样斑块形态学及性质特征。并对各指标间的相关性进行分析。结果sCD40L浓度在易损斑块破裂组高于非破裂组[(474±126)pg/mlvs(238±35)pg/ml],差异有统计学意义(P<0.05),且单核细胞趋化蛋白-1(MCP-1)和P选择素(sPE)在易损斑块破裂组高于非破裂组,差异有统计学意义(P<0.05,P<0.01),但白介素-8(IL-8)和IL-6差异无统计意义(均P>0.05)。sCD40L与sPE、MCP-1呈高度正相关(依次为r=0.93,P<0.01;r=0.57,P<0.01),而与IL-8和IL-6未见相关性。sCD40L在ACS中合并高血压组(279.8pg/ml±95.7pg/ml)较非合并高血压组(99.2pg/ml±56.4pg/ml)升高(P<0.05)。结论sCD40L、MCP-1和sPE可能是冠脉易损斑块发生急性破裂的血清学标志。  相似文献
9.
Background Osteosarcoma is one of the most common primary malignant tumors of bone with poor prognosis. TNF-related apoptosis inducing ligand (TRAIL) is a member of the tumor necrosis factor (TNF) cytokine family. TRAIL induces apoptosis in various tumor cell lines but is not found to be cytotoxic to many normal cell types in vitro. We investigated the cytotoxic activity of TRAIL and chemotherapeutic agents, including methotrexate (MTX), doxorubicin (DOX) and cisplatin (CDDP), on established osteosarcoma cell line—OS-732.Methods OS-732 cells were incubated with chemotherapeutic agents MTX,DOX and CDDP at various peak plasma concentrations(PPC), 0.1PPC,1PPC and 10PPC, alone or with 100 ng/ml of TRAIL for 24 hours or 48 hours. MTT was used to evaluate the cytotoxic activity of different agents on OS-732. The apoptosis proportion was assayed by flow cytometry. Cellular morphologic changes were observed by phase contrast microscope, scan electron microscope, and transmission electron microscope.Results The inhibitory rate was (24.438±3.414)% with TRAIL of 100 ng/ml for 24 hours. The cells were responsive to DOX and CDDP with a dose-effect relationship (P&lt;0.05). In OS-732 cells, DOX and CDDP cooperated synergistically with TRAIL when incubated the cells with them for 24 hours (the combined inhibitory rate is (58.360±2.146)% and (54.101±2.721)%, respectively). TRAIL alone or drugs alone induced the apoptosis rate was less than 25% (P&lt;0.05). However, the combination of TRAIL and MTX did not present synergistic effects on OS-732 cells (P&gt;0.05, compared with TRAIL alone). Conclusions Osteosarcoma OS-732 cells were not responsive to TRAIL-induced apoptosis. DOX and CDDP sensitize osteosarcoma OS-732 cells to TRAIL-induced apoptosis. The combination of TRAIL and MTX presented no synergistic effects on killing OS-732 cells.  相似文献
10.
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