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41.
目的:观察星状神经节阻滞联合丁咯地尔治疗椎动脉型颈椎病(CSA)的临床效果。方法将120例 CSA 患者分为研究组与对照组,每组60例。研究组给予神经节阻滞联合丁咯地尔静脉注射治疗,对照组单纯采用丁咯地尔静脉注射治疗。测定并比较两组治疗前后椎动脉和基底动脉平均血流速度,观察两组患者治疗效果。结果治疗后,研究组总有效率为95.00%显著高于对照组的71.67%,差异有统计学意义(χ2=24.474,P <0.05)。两组治疗后的椎动脉血流速度较治疗前均明显提升,差异有统计学意义(均 P <0.05);研究组椎动脉血流速度为(38.44±2.20)cm/s 明显高于对照组的(34.36±3.50)cm/s,差异有统计学意义(t=7.645,P <0.05)。两组治疗后基底动脉血流速度较治疗前有均明显提升,差异有统计学意义(均 P <0.05),研究组治疗后椎动脉血流速度(56.34±4.10)cm/s 明显高于对照组的(47.69±3.90)cm/s,差异有统计学意义(t =11.841,P <0.05)。结论星状神经节阻滞联合丁咯地尔治疗椎动脉型颈椎病临床疗效明显,较单纯采用药物有显著优势,值得进一步推广。  相似文献   
42.
BACKGROUNDExosomes play an important role in metabolic-associated fatty liver disease (MAFLD), but the mechanism by which exosomes participate in MAFLD still remain unclear.AIMTo figure out the function of lipotoxic exosomal miR-1297 in MAFLD.METHODSMicroRNA sequencing was used to detect differentially expressed miRNAs (DE-miR) in lipotoxic exosomes derived from primary hepatocytes. Bioinformatic tools were applied to analyze the target genes and pathways regulated by the DE-miRs. Quantitative real-time PCR (qPCR) was conducted for the verification of DE-miRs. qPCR, western blot, immunofluorescence staining and ethynyl-20-deoxyuridine assay were used to evaluate the function of lipotoxic exosomal miR-1297 on hepatic stellate cells (LX2 cells). A luciferase reporter experiment was performed to confirm the relationship of miR-1297 and its target gene PTEN. RESULTSMicroRNA sequencing revealed that there were 61 exosomal DE-miRs (P < 0.05) with a fold-change > 2 from palmitic acid treated primary hepatocytes compared with the vehicle control group. miR-1297 was the most highly upregulated according to the microRNA sequencing. Bioinformatic tools showed a variety of target genes and pathways regulated by these DE-miRs were related to liver fibrosis. miR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes by qPCR. Fibrosis promoting genes (α-SMA, PCNA) were altered in LX2 cells after miR-1297 overexpression or miR-1297-rich lipotoxic exosome incubation via qPCR and western blot analysis. Immunofluorescence staining and ethynyl-20-deoxyuridine staining demonstrated that the activation and proliferation of LX2 cells were also promoted after the above treatment. PTEN was found to be the target gene of miR-1297 and knocking down PTEN contributed to the activation and proliferation of LX2 cells via modulating the PI3K/AKT signaling pathway.CONCLUSIONmiR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes. The lipotoxic hepatocyte-derived exosomal miR-1297 could promote the activation and proliferation of hepatic stellate cells through the PTEN/PI3K/AKT signaling pathway, accelerating the progression of MAFLD.  相似文献   
43.
目的 应用黏着斑激酶相关非激酶(FRNK)表达质粒瞬时转染纤维连接蛋白(FN)预刺激的肝星状细胞(HSC),探讨FRNK对HSC凋亡及细胞外信号调节激酶(ERK)的影响.方法 在体外,以FN诱导HSC增殖,采用脂质体介导的方法用FRNK表达质粒瞬时转染HSC,应用膜联蛋白/碘化丙啶双标记流式细胞术、DNA凝胶电泳技术和透射电镜技术检测细胞的凋亡,Western blot及RT-PCR方法检测FRNK、黏着斑激酶(FAK),p FAK(Tyr397)、半胱氨酸天冬氨酸特异性蛋白酶-3(caspase-3)、ERK1、p-ERK蛋白及其mRNA表达. 结果FRNK表达质粒成功转染HSC,在翻译后水平抑制FAK磷酸化.与空质粒组比较,FRNK表达质粒转染HSC48 h后,HSC凋亡率由9.28%±1.05%增至25.37%±1.92%(P<0.01),caspase-3蛋白由185.82±9.69增至264.17±12.60(P<0.01),caspase-3 mRNA由1.07±0.27增至4.19±0.48(P<0.01).FRNK抑制FAK磷酸化和在翻译和转录水平抑制ERK1、p-ERK的表达,而FN则促进FAK和ERK1,p-ERK在翻译和转录水平的表达. 结论在脂质体介导下瞬时转染FRNK表达质粒,可使外源性的FRNK在HSC内大量表达,在翻译后水平抑制FAK磷酸化;并可能通过FAK-ERK信号转导通路诱导FN刺激的HSC发生凋亡.  相似文献   
44.
氧化苦参碱对大鼠肝星状细胞增殖的影响   总被引:7,自引:0,他引:7  
目的:研究氧化苦参碱对大鼠肝星状细胞增殖的影响,探讨其抗肝纤维化的机理。方法:用链霉蛋白酶和胶原酶原位灌流,Nycodenz密度梯度离心分离大鼠肝星状细胞,并以MTT比色法观察氧化苦参碱对肝星状细胞增殖的效应。结果:氧化苦参碱可影响肝星状细胞的增殖,氧化苦参碱浓度在0.5~16μg/ml时对肝星状细胞增殖有抑制作用(P<0.01)。结论:氧化苦参碱可抑制肝星状细胞增殖,有抗肝纤维化的作用。  相似文献   
45.
AIM: To investigate the effect of interferon-α(IFN-α) on preventing or reversing hepatic fibrosis in rat experimental model induced by CCl4.METHODS: One hundred and ten Sprague-Dawley rats were divided into five groups: group A (normal controls,n=18), group B (fibrotic model controls, n=22), group C (IFN-α prevention, n=22) initially treated with intra-muscular injection of IFN-α in saline daily at the doses of 1&#215;105U for 6wk, group D (IFN-α treatment, n=24) treated with intra-muscular injection of IFN-α in saline daily at the doses of 1&#215;105U for 6wk after the first 6wk, group E (0.9% sodium chloride treatment control, n=24) treated with intra-muscular injection of 0.01mL/kg daily for 6wk after the first 6wk. At the end of the experiment, all rats of each group were killed. Samples of the liver obtained by biopsy were subjected to histological, immunohistochemical and electron microscopic studies for the expressions of transforming growth factor-β1(TGF-β1) and α-smooth muscle actin (α-SMA).RESULTS: The expressions of TGF-β1, the number of activated hepatic stellate cells and α-SMA in hepatic tissue of group C were significantly less than those of group B(P&lt;0.01). The degree of fibrosis score in group B was also significantly less than that of group C under light microscope (P&lt;0.01).CONCLUSION: IFN-α can inhibit the production of TGF-β1, decrease HSC activation and stimulate its apoptosis.  相似文献   
46.
目的 研究转化生长因子β(TGF-β)信号传导通路的阻断,对鼠肝星状细胞(HSC)培养激活的影响。 方法 利用腺病毒AdT β-ExR的表达产物阻断HSCs中TGF-β信号传导。用酶联免疫吸附试验,Western blot及免疫组织化学等方法检测HSCs中Ⅰ型胶原蛋白、α-平滑肌肌动蛋白(α-SMA)的表达及细胞增殖。 结果 感染AdT β—ExR与感染AdLacZ的HSCs相比,Ⅰ型胶原蛋白的表达量为对照组的42.99%(q=9.100,,P<0.001),α-SMA的表达明显被抑制,而细胞增殖指标5-溴脱氧尿苷的参入量,后者为前者的49.24%(q=7.835,.P<0.001)。 结论 阻断TGF-β信号传导能显著地抑制HSCs的培养激活,但促进HSCs的分裂。通过腺病毒AdT β-ExR的表达产物阻断TGF-β信号传导作为抑制肝纤维化的方法,还需深入一步的研究。  相似文献   
47.
AIM: To evaluate the effects of dietary supplementation with vitamin E and selenium on proliferation and apoptosis of hepatic stellate cells (HSCs), in acute liver injury induced by CCl4, and to explore their role in the recovery from hepatic fibrosis phase. METHODS: An acute liver damage model of rats was established by intraperitoneal injection of carbon tetrachloride (0.3 mL/100 g body weight) twice a week, then the rats were killed at 6, 24, 48, and 72 h after the first and third injection, respectively. A liver fibrosis model was established by the same injection for 8 wk. Then three rats were killed at 3, 7,14, and 28 d after the last injection, respectively. The rats from the intervention group were fed with chow supplemented with vitamin E (250 mg/kg) and selenium (0.2 mg/kg), and the rats in the normal control group and pathological group were given standard chow. Livers were harvested and stained with hematoxylin and eosin, Sirius red. Activated HSCs were determined by α-smooth muscle actin immunohistochemistry staining. Apoptotic HSCs were determined by dual staining with the terminal deoxynucleotidyl transferase UTP nick end labeling (TUNEL) and α-smooth muscle actin immunohistochemistry. Serum alanine aminotransferase and aspartate aminotransferase were also analyzed. RESULTS: In the acute liver damage model, the degree of liver injury was more serious in the pathological group than in the intervention group. At each time point, the number of activated HSCs was less in the intervention group than in the pathological group, while the number of apoptotic HSCs was more in the intervention group than in the pathological group. In the liver fibrosis model, the degree of liver fibrosis was more serious in the pathological group than in the intervention group. At each time point, the number of activated HSCs was less in the intervention group than in the pathological group, and the number of apoptotic HSCs was more in the intervention group than in the pathological group. CONCLUSION: Vitamin E and selenium supplementation at the given level can inhibit CCl4-induced activation and proliferation of HSCs and promote the apoptosis of activated HSCs in acute damage phase. Vitamin E and selenium can also effectively decrease the degree of hepatic fibrosis and promote the recovery process.  相似文献   
48.
目的观察肝素在体外对肝纤维化大鼠肝星状细胞增殖及分泌的影响,并探讨其作用机制。方法应用Nycodenz分离肝纤维化大鼠的肝星状细胞置培养板中,并分为三组。A、B组分别加入1000μg/ml及2000μg/ml肝素,C组不用药。应用MTT比色法检测各组肝星状细胞的增殖状况,免疫细胞化学检测各组肝星状细胞中α-平滑肌肌动蛋白(α-SMA)、转化生长因子-β1(TGF-β1)、层粘连蛋白(LN)的表达。结果OD值A组为0.0626±0.0137,B组为0.0746±0.0131,C组为0.1106±0.0198,A、B组均显著低于C组(P均<0.05),B组低于A组(P>0.05);C组肝星状细胞胞质中可见α-SMA、TGF-β1和LN明显表达,A、B组各指标表达均低于C组(P分别<0.01和<0.05),A组表达低于B组(P<0.05)。结论肝素可抑制肝纤维化大鼠肝星状细胞的增殖及胶原分泌,作用机制可能是抑制肝星状细胞表达TGF-β1。  相似文献   
49.
肝纤维化是动态的病理过程,是反复肝损伤引起细胞外基质(ECM)合成和降解失衡,导致其过度沉积的结果。活化的肝星状细胞(HSC)通过产生细胞外基质蛋白和分泌基质金属蛋白酶(MMPS)在肝纤维化病理生理过程中发挥重要作用。尿激酶型纤溶酶原激活物(uPA)可转化纤溶酶原为纤溶酶,活化MMPs,降解多种ECM成分。纤溶酶原激活物抑制剂-1(PAI-1)具有抑制uPA的作用。基质金属蛋白酶抑制剂1(TIMP-1)抑制MMPs对细胞外基质有降解作用。α平滑肌肌动蛋白(α-SMA)是HSC活化标志。我们测定不同肝纤维化分级中α-SMA、基质金属蛋白-1(MMP-1)、TIMP-1蛋白表达以及血浆uPA、PAI-1的水平,旨在了解它们在肝纤维化发展过程中的作用,从而为临床治疗肝硬化提供理论依据。  相似文献   
50.
目的 研究血小板衍生生长因子(PDGF)受体β亚单位在肝纤维化组织中的动态表达及其与细胞外基质成分的相关性。 方法 将动物分为正常对照组和模型组,用C Cl4复制肝纤维化模型,用免疫组化方法动态检测PDGF受体β亚单位、α~平滑肌抗体(α-SMA)、Ⅰ、Ⅲ型胶原在肝纤维化组织中的表达,将免疫组化结果行图像扫描半定量后进行统计学分析并计算其相关性。 结果 随着肝纤维化程度的加重,PDGF受体β亚单位、α—SMA表达逐渐增加,Ⅰ、Ⅲ型胶原的表达也逐步增加。在2周时PDGF受体β亚单位与Ⅰ、Ⅲ型胶原的相关性不明显,但与α-SMA呈显著相关,其相关系数为0.6 2(P<0.05);在4周时其与Ⅰ、Ⅲ型胶原和α—SMA的相关系数分别为0.74、0.60和0.69(P<0.05);在6周时其与Ⅰ、Ⅲ型胶原和α-SMA的相关系数分别为0.83、0.67和0.81(P<0.05)。 结论 PDGF受体β亚单位在肝纤维化的发生发展中起重要作用,抑制PDGF受体β亚单位的表达可望能减少细胞外基质的合成。  相似文献   
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