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451.
目的 观察全反式维甲酸(ATRA)与奥沙利铂(L-OHP)对人胃癌BGC-823细胞增殖的影响.方法 分别用ATRA和L-OHP单独及联合作用于人胃癌BGC-823细胞,采用MTT法检测细胞增殖抑制率,倒置显微镜下观察细胞形态变化;流式细胞仪检测细胞凋亡率及细胞周期;免疫细胞化学技术检测BGC-823细胞中Bcl-2和Survivin蛋白的表达情况.结果 ATRA作用后BGC-823细胞的增殖受到抑制,细胞形态发生了改变,凋亡比例明显增加;与L-OHP联用后,该作用加强.胃癌 BGC-823细胞中Bcl-2和Survivin蛋白的表达在ATRA作用后均受到抑制,ATRA与L-OHP联合作用后蛋白表达的阳性率进一步降低.结论 ATRA能抑制人胃癌BGC-823细胞的生长,与L-OHP联用具有协同抑制作用,其机制可能与下调Bcl-2和Survivin蛋白表达有关.  相似文献   
452.
目的 观察自发性高血压大鼠(spontaneous hypertensive rats, SHR)与Wistar-Kyoto(WKY)大鼠肠系膜动脉血管平滑肌细胞(vascular smooth muscle cells, VSMCs)大电导钙激活钾通道(large conductance calcium-activated potassium channel, BKCa)电流及通道α亚单位表达的差异.方法 实验采用16~18周龄SHR(N=20)及WKY(N=20)大鼠,尾套法测量大鼠尾动脉血压;胶原酶分离VSMCs,全细胞膜片钳技术记录全细胞总钾电流密度及BKCa电流;激光共聚焦观察BKCaα亚单位在VSMCs胞膜及胞质内的分布.结果 SHR较WKY大鼠的收缩压与舒张压均有显著升高(P<0.05);全细胞外向钾电流密度及BKCa电流密度均有显著性增加(P<0.05);SHR的BKCaα亚单位在胞膜及胞质内均有广泛分布,SHR大鼠VSMCs胞质与胞膜的荧光强度较WKY大鼠均有显著性升高(P<0.05).结论 BKCa电流密度增加可能与BKCa通道α亚单位的表达增多有关,SHR大鼠VSMCs的BKCa电流密度增加引起血管的舒张,不能抵消平滑肌细胞的肌源性收缩可能是导致高血压的发生机制之一.  相似文献   
453.
454.
目的 探讨非CO2依赖型细胞培养系统对前列腺癌PC-3细胞增殖的影响.方法 对前列腺癌PC-3细胞采取非CO2依赖型细胞培养系统及CO2依赖型细胞培养系统进行培养,均在37℃培养箱(大气环境)和37℃,50 mL/LCO2培养箱条件下,检测分析两种体系pH的变化;采用细胞增殖曲线及克隆形成实验检测细胞生长差异情况;并使用RT-PCR技术检测分析两种体系下的前列腺癌细胞中survivin、caspase-3基因的表达差异.结果 两种培养系统条件下,细胞培养基pH变化趋势一致(P>0.05);两种培养系统下PC-3细胞生长增殖未见差异(P>0.05);RT-PCR法检测显示两种培养系统下表达survivin、caspase-3未见差异(P>0.05).结论 前列腺癌非CO2依赖型细胞培养系统对细胞增殖、基因表达等方面与前列腺癌CO2依赖型细胞培养系统无显著差异.  相似文献   
455.
Objective To analyze proliferation and differentiation of glial fibrillary acid protein (GFAP)- and nestin-positive (GFAP+/nestin+) cells isolated from the subventricular zone following fluid percussion brain injury to determine whether GFAP+/nestin+ cells exhibit characteristics of neural stem cells. Methods Male Sprague-Dawley rats, aged 12 weeks and weighing 200-250 g, were randomly and evenly assigned to normal control group and model group. In the model group, a rat model of fluid percussion brain injury was established. Five days later, subventricular zone tissue was resected from each group and made into single cell suspension. After serum-free neural stem cell medium culture and subsequent serum-induced differentiation, cell type, proliferation and differentiation capacities were determined by immunofluorescence staining and flow cytometry. Results At 3-7 days after fluid percussion brain injury, nestin+/GFAP+ cells in the single cell suspension from the model group significantly outnumbered those from the normal control group (P<0.01). In the model group, an increased number of small neurospheres with smooth cell edge and bulged center formed after primary culture, and were clearly visible with the increase of culture time and medium replacement. After several passages, many clonal spheres were obtained, suggesting strong self-proliferatiing capacity. Neurospheres from the model group differentiated into astrocytes, neurons and oligodendrocytes. Conclusion GFAP+/nestin+ cells isolated from the adult rat subventricular zone after fluid percussion brain injury are thought to be neural stem cells because of their self-renewal and multi-differentiation capacities.  相似文献   
456.
Objective To investigate the effect of oleanolic acid (OA) on apoptosis, correlation between apoptosis and intracellular calcium, and its mechanism in human lung adenocarcinoma cell line A549. Methods Human lung adenocarcinoma A549 cells were incubated in vitro and assigned with OA concentrations of 0, 10, 20 and 40μg/mL. The apoptosis status of A549 cell line was detected with Annexin V-FITC/PI by flow cytometry (FCM); fluorescence intensity (FI) of A549 cells was assessed and the level of intracellular calcium was calculated at 24 hour of OA intervention. The relation between apoptosis and calcium FI was illustrated by curve fitting. Results FCM showed that 10, 20 and 40μg/mL of OA could induce A549 cell apoptosis, which followed a concentration-effect pattern; 24-hour intervention with 20μg/mL and 40μg/mL OA showed increased A549 cell apoptosis, and was significantly different from that with 0μg/mL OA (P<0.01). The FI of intracellular calcium concentration in 10, 20 and 40μg/mL OA groups was significantly higher than that in 0μg/mL group after 24 hours' intervention, and the FI showed a trend of increase with increased OA concentration (P<0.01). Curve fitting showed a significant correlation between apoptosis rate and intracellular calcium concentration in A549 cells (r=0.981, P<0.01). Regression equation was Y=0.508X-1.627. Conclusion OA plays a role in inducing apoptosis of human lung adenocarcinoma cells in a concentration-dependent manner. The OA-induced apoptosis is responsible for intracellular calcium overload of the tumor.  相似文献   
457.
Objective To investigate the effects of acitretin on T helper cell (Th) 1/Th2 balance and Th17 cells in psoriasis vulgaris (PV) patients. Methods A total of 13 men and 17 women with PV were investigated. 10 mg of acitretin was administered twice a day for 8 weeks for intervention therapy. Serum levels of interferon-gamma (IFN-γ), interleukin (IL)-4 and IL-17 were measured by enzyme-linked immunosorbent assay. T, Th1, Th2 and Th17 cells in skin biopsies were counted with double-labeled immunofluorescence. Psoriasis Area and Severity Index (PASI) score was calculated before and 8 weeks after treatment. Results Before treatment PV patients had higher serum levels of IFN-γ and IL-17, and increased T, Th1 and Th17 cells in skin biopsies. After treatment, both serum levels of IFN-γ and IL-17, and T, Th1 and Th17 cells infiltrating in PV skin decreased significantly. Th1/Th2 balance was restored to normal. However, their IL-4 and Th2 cells showed no significant change throughout the therapy. Conclusion Acitretin exerts influence on dermal Th1/Th2 balance and Th17 cell infiltration, so does it on production of systematic inflammatory cytokines IFN-γ and IL-17 in PV patients. However, Th2 cells and its derivative cytokine-IL-4 are not affected.  相似文献   
458.
目的 探讨临床I期(cI期)非小细胞肺癌(NSCLC)中血管内皮生长因子C(VEGF-C)的表达、微淋巴管密度(MLVD)、淋巴结转移及其与化疗的关系.方法 应用免疫组化SP法检测cI期NSCLC癌组织、癌旁组织及正常肺组织中VEGF-C的表达,计数MLVD,检测血清VEGF-C蛋白含量,并结合病理淋巴结转移情况和化疗前、后VEGF-C蛋白含量的变化进行统计学分析.结果 在NSCLC中,VEGF-C呈过度表达,与癌旁组织和正常肺组织相比差异有统计学意义(P<0.01);在癌组织中淋巴结阳性组和淋巴结阴性组的VEGF-C阳性表达率(91.9% vs. 76.7%)、MLVD[(20.0±4.8) vs.(10.6±2.2)]差异有统计学意义(P<0.01);血清VEGF-C蛋白含量与组织检测VEGF-C具有较好的相关性(r=0.848, P<0.01),化疗患者化疗前血清VEGF-C蛋白含量(237±72.3)ng/mL较化疗后(178±69.2)ng/mL变化明显(P<0.01).结论 VEGF-C在cI期NSCLC中过度表达与淋巴结转移密切相关;血清VEGF-C蛋白含量测定是一种有效的VEGF-C检测方法;化疗前、后血清VEGF-C蛋白含量的变化可以预测化疗效果.  相似文献   
459.
目的探究黄芪甲苷对退变髓核细胞功能的影响及其作用机制。方法原代培养正常与退变髓核细胞并观察,免疫组化检测细胞中胶原蛋白Ⅱ(collagenⅡ)的表达;分别采用20、40、60、80μg/mL的黄芪甲苷处理细胞,通过CCK-8和MTT试剂盒检测细胞活力和增殖,流式细胞术检测细胞凋亡情况;Western blotting检测凋亡相关基因Bcl-2、Bax和沉默信息调节因子2同源蛋白1(SIRT1)、过氧化物酶体增殖物激活受体γ辅助激活因子-1(PGC-1α)的表达及其乙酰化和磷酸化水平;比色法检测丙二醛(MDA)、超氧化物岐化酶(SOD)、β-galactosidase和三磷酸腺苷(ATP)的含量。结果与正常髓核细胞相比,退变髓核组织中坏死细胞更多,且collagenⅡ表达降低;细胞经不同浓度黄芪甲苷处理后,40μg/mL黄芪甲苷不仅能显著提高退变髓核细胞活力,促进细胞增殖并抑制其凋亡,而且能上调细胞中SIRT1、PGC-1α的蛋白表达和PGC-1α磷酸化水平,下调PGC-1α乙酰化水平,增加SOD和ATP含量,降低MDA和β-galactosidase含量。结论黄芪甲苷可能通过激活SIRT1/PGC-1α信号通路促进髓核细胞的增殖和存活。  相似文献   
460.
目的观察每搏量变异度(SVV)指导的目标导向性液体治疗(GDFT)与常规补液对老年腹腔镜胃癌根治术患者术中循环动力学及术后胃肠功能恢复的影响。方法选择择期行腹腔镜胃癌根治术的老年患者80例,采用随机数字表法分为目标组和常规组,常规组采用常规补液方案进行补液;目标组采用SVV为指导的目标管理补液方案进行补液。比较两组术中血流动力学指标和血管活性药物使用情况;比较两组术中输液量及其种类、失血量、尿量、术前术后1d血色素(Hb)、血球压积(Hct)、尿素氮(BUN)、肌酐(Ccr)水平以及术后胃肠功能恢复情况和术后并发症情况(包括恶心呕吐、心力衰竭、肺部感染、吻合口渗漏或腹腔感染、肠梗阻等)。结果 1两组患者基础值(T1点)平均动脉压(MAP)、心率(HR)比较差异均无统计学意义(P>0.05),两组患者麻醉不同时间段比较发现,全麻诱导后即刻(T2)、建立气腹后(T3)、标本切除时(T4)MAP、HR与T1的差值目标组均显著低于常规组(P<0.05),而胃肠吻合时(T5)、手术结束后即刻(T6)MAP、HR与T1的差值两组比较均无统计学意义(P>0.05),两组术中血流动力学不良事件和血管活性药物使用有统计学差异(P<0.05);2术中液体总输入量、晶体输入量目标组均低于常规组(P<0.05),胶体液的输入量目标组高于常规组(P<0.05);3目标组尿量和出血量均低于常规组(P<0.05);4两组术前术后1dHb、Hct、BUN、Ccr水平无明显差异(P>0.05);5目标组术后恢复排气时间、进食流质食物时间和排便时间明显短于常规组(P<0.05),术后并发症低于常规组(P<0.05)。结论以SVV为指导的GDFT方案不仅能够维持老年腹腔镜胃癌根治术患者术中血流动力学的平稳,而且术后胃肠功能恢复快,并发症少,是较传统补液方案更为理想的液体治疗方案。  相似文献   
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