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101.
目的:研究主动脉夹层与阻塞性睡眠呼吸暂停低通气综合征(OSAHS)的关系。方法:回顾分析41例合并高血压的主动脉夹层患者的临床资料,设为主动脉夹层组,并选取41例具有年龄、性别及体质量指数相近的高血压患者作为对照组,分析OSAHS与主动脉夹层之间的关系。结果:夹层组的阻塞性睡眠呼吸暂停综合征发病率较对照组明显升高(P0.05),且夹层组合并OSAHS者睡眠呼吸暂停低通气指数(AHI)较对照组升高,平均Sa O2降低(P0.05)。结论:主动脉夹层的发生与睡眠呼吸暂停低通气综合征可能有关。  相似文献   
102.
目的 探讨法舒地尔对阻塞性黄疸大鼠肝缺血再灌注损伤的影响.方法 成熟SD大鼠160只随机分成实验组(A组)及对照组(B组)两大组,两组再分别分为4个亚组,分别为假手术组(A1、B1组)、阻塞性黄疸组(A2、B2组)、肝缺血再灌注组(A3、B3组)及阻塞性黄疸+肝缺血再灌注组(A4、B4组).A2、B2组采用双重结扎切断胆总管的方法建立模型,A3、B3组采用阻断肝门部血管30 min后再灌注的方法建立模型.A4、B4组于建立阻塞性黄疸模型1周后再次建立缺血再灌注模型.A组于缺血前30 min腹腔内注射法舒地尔10 mg/kg,B组对应注射等量生理盐水.两组分别于再灌注0h、1h、2h、6h取材,检测血清肝功能改变及血清内皮素1水平.采用SPSS软件对重复测量结果进行统计分析,光镜下观察肝脏病理学改变.结果 实验组各时点血清转氨酶水平、血清内皮素1水平均显著低于对照组(P<0.05),实验组各时点光镜下肝脏病理组织学损伤也较对照组明显减轻.结论 法舒地尔对阻塞性黄疸大鼠的肝缺血再灌注损伤具有保护作用.  相似文献   
103.
目的:通过对早、中期糖尿病肾病(DN)患者观察,探讨益肾固精方干预DN肾小管间质损害作用及机制。方法:临床纳入66例早、中期DN患者进行益肾固精方联合缬沙坦(中西医结合治疗组)与单纯缬沙坦(西药组)治疗比较,3个月后观察治疗前后空腹血糖(FPG)、血脂、纤维蛋白原(Fbg)、血粘度、血白蛋白(Alb)及肾脏损伤血、尿液标志物变化。结果:共纳入观察病例66例,脱落及剔除共6例,最终纳入统计60例。治疗前后比较:(1)两组患者中医证候积分均显著降低,中西医结合治疗组优于单用西药组(P0.05),前者证候疗效有效率86.7%,明显高于后者的76.7%(P0.05)。(2)中西医结合治疗组显著降低尿微量白蛋白(MA)(P0.01)、血尿胱抑素C、尿β2-微球蛋白(P0.05)、血脂、Fbg、血黏度(P0.05,P0.01),提升血Alb(P0.05),尤其在降低尿MA、Fbg方面疗效优于单用缬沙坦组。结论:益肾固精方可有效改善DN患者的临床症候,提高生活质量,通过调节血液流变学、凝血因子,减轻肾小管间质损伤,降低尿蛋白的异常排泄,其远期疗效值得进一步关注。  相似文献   
104.
目的:观察雷公藤内酯醇(TP)对IgA肾病(IgAN)大鼠尿蛋白和足细胞nephrin、podocin蛋白及mRNA表达的影响。方法:采用牛血清白蛋白+四氯化碳+脂多糖的方法建立IgAN大鼠模型。将60只大鼠随机分为正常组、模型组、洛丁新组、TP剂量组、TP中剂量组、TP高剂量组,每组10只。于0,10,14周收集血尿标本,并处死大鼠留取肾组织标本。检测24 h尿蛋白定量,血生化指标,分别采用实时定量PCR及ELISA法检测肾组织nephrin、podocin mRNA和蛋白表达。结果:(1)实验前各组大鼠尿蛋白差异无统计学意义(P>0.05),第10周末各造模组蛋白尿均明显高于正常组(P<0.01),第14周末TP各剂量组及洛丁新组蛋白尿均较模型组明显减少(P<0.01),TP高剂量组Alt值高于其余各组(P<0.05);(2)与正常组相比,模型组nephrin、podocin蛋白、mRNA表达明显降低(P<0.01);TP各剂量组及洛丁新组nephrin、podocin蛋白、mRNA表达均较模型组明显增高(P<0.05);TP中、高剂量组较洛丁新组nephrin、podocin蛋白浓度显著增高(P<0.05);TP各剂量组与洛丁新组及TP各剂量组间nephrin、podocin mRNA表达均差异无统计学意义(P>0.05)。结论:TP能够明显减轻IgAN大鼠的蛋白尿,且能明显提高肾组织nephrin、podocin mRNA及蛋白的表达。提示TP能调节IgAN足细胞相关分子nephrin、podocin基因及蛋白的表达,减少足细胞损害,减少尿蛋白。  相似文献   
105.
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107.
Diabetic kidney disease (DKD) is the most common cause of ESRD in the United States. Podocyte injury is an important feature of DKD that is likely to be caused by circulating factors other than glucose. Soluble urokinase plasminogen activator receptor (suPAR) is a circulating factor found to be elevated in the serum of patients with FSGS and causes podocyte αVβ3 integrin-dependent migration in vitro. Furthermore, αVβ3 integrin activation occurs in association with decreased podocyte-specific expression of acid sphingomyelinase-like phosphodiesterase 3b (SMPDL3b) in kidney biopsy specimens from patients with FSGS. However, whether suPAR-dependent αVβ3 integrin activation occurs in diseases other than FSGS and whether there is a direct link between circulating suPAR levels and SMPDL3b expression in podocytes remain to be established. Our data indicate that serum suPAR levels are also elevated in patients with DKD. However, unlike in FSGS, SMPDL3b expression was increased in glomeruli from patients with DKD and DKD sera-treated human podocytes, where it prevented αVβ3 integrin activation by its interaction with suPAR and led to increased RhoA activity, rendering podocytes more susceptible to apoptosis. In vivo, inhibition of acid sphingomyelinase reduced proteinuria in experimental DKD but not FSGS, indicating that SMPDL3b expression levels determined the podocyte injury phenotype. These observations suggest that SMPDL3b may be an important modulator of podocyte function by shifting suPAR-mediated podocyte injury from a migratory phenotype to an apoptotic phenotype and that it represents a novel therapeutic glomerular disease target.  相似文献   
108.
Phospholipase A2 receptor 1 (PLA2R) is a target autoantigen in 70% of patients with idiopathic membranous nephropathy. We describe the location of a major epitope in the N-terminal cysteine-rich ricin domain of PLA2R that is recognized by 90% of human anti-PLA2R autoantibodies. The epitope was sensitive to reduction and SDS denaturation in the isolated ricin domain and the larger fragment containing the ricin, fibronectin type II, first and second C-type lectin domains (CTLD). However, in nondenaturing conditions the epitope was protected against reduction in larger fragments, including the full-length extracellular region of PLA2R. To determine the composition of the epitope, we isolated immunoreactive tryptic fragments by Western blotting and analyzed them by mass spectrometry. The identified peptides were tested as inhibitors of autoantibody binding to PLA2R by surface plasmon resonance. Two peptides from the ricin domain showed strong inhibition, with a longer sequence covering both peptides (31-mer) producing 85% inhibition of autoantibody binding to PLA2R. Anti-PLA2R antibody directly bound this 31-mer peptide under nondenaturing conditions and binding was sensitive to reduction. Analysis of PLA2R and the PLA2R-anti-PLA2R complex using electron microscopy and homology-based representations allowed us to generate a structural model of this major epitope and its antibody binding site, which is independent of pH-induced conformational change in PLA2R. Identification of this major PLA2R epitope will enable further therapeutic advances for patients with idiopathic membranous nephropathy, including antibody inhibition therapy and immunoadsorption of circulating autoantibodies.  相似文献   
109.
Diabetic kidney disease (DKD) is associated with oxidative stress and mitochondrial injury. Myo-inositol oxygenase (MIOX), a tubular-specific enzyme, modulates redox imbalance and apoptosis in tubular cells in diabetes, but these mechanisms remain unclear. We investigated the role of MIOX in perturbation of mitochondrial quality control, including mitochondrial dynamics and autophagy/mitophagy, under high-glucose (HG) ambience or a diabetic state. HK-2 or LLC-PK1 cells subjected to HG exhibited an upregulation of MIOX accompanied by mitochondrial fragmentation and depolarization, inhibition of autophagy/mitophagy, and altered expression of mitochondrial dynamic and mitophagic proteins. Furthermore, dysfunctional mitochondria accumulated in the cytoplasm, which coincided with increased reactive oxygen species generation, Bax activation, cytochrome C release, and apoptosis. Overexpression of MIOX in LLC-PK1 cells enhanced the effects of HG, whereas MIOX siRNA or d-glucarate, an inhibitor of MIOX, partially reversed these perturbations. Moreover, decreasing the expression of MIOX under HG ambience increased PTEN-induced putative kinase 1 expression and the dependent mitofusin-2–Parkin interaction. In tubules of diabetic mice, increased MIOX expression and mitochondrial fragmentation and defective autophagy were observed. Dietary supplementation of d-glucarate in diabetic mice decreased MIOX expression, attenuated tubular damage, and improved renal functions. Notably, d-glucarate administration also partially attenuated mitochondrial fragmentation, oxidative stress, and apoptosis and restored autophagy/mitophagy in the tubular cells of these mice. These results suggest a novel mechanism linking MIOX to impaired mitochondrial quality control during tubular injury in the pathogenesis of DKD and suggest d-glucarate as a potential therapeutic agent for the amelioration of DKD.  相似文献   
110.
Kidney transplantation is a viable treatment for select patients with HIV and ESRD, but data are lacking regarding long-term outcomes and comparisons with appropriately matched HIV-negative patients. We analyzed data from the Scientific Registry of Transplant Recipients (SRTR; 2002–2011): 510 adult kidney transplant recipients with HIV (median follow-up, 3.8 years) matched 1:10 to HIV-negative controls. Compared with HIV-negative controls, HIV-infected recipients had significantly lower 5-year (75.3% versus 69.2%) and 10-year (54.4% versus 49.8%) post-transplant graft survival (GS) (hazard ratio [HR], 1.37; 95% confidence interval [95% CI], 1.15 to 1.64; P<0.001) that persisted when censoring for death (HR, 1.43; 95% CI, 1.12 to 1.84; P=0.005). However, compared with HIV-negative/hepatitis C virus (HCV)–negative controls, HIV monoinfected recipients had similar 5-year and 10-year GS, whereas HIV/HCV coinfected recipients had worse GS (5-year: 64.0% versus 52.0%, P=0.02; 10-year: 36.2% versus 27.0%, P=0.004 [HR, 1.38; 95% CI, 1.08 to 1.77; P=0.01]). Patient survival (PS) among HIV-infected recipients was 83.5% at 5 years and 51.6% at 10 years and was significantly lower than PS among HIV-negative controls (HR, 1.34; 95% CI, 1.08 to 1.68; P<0.01). However, PS was similar for HIV monoinfected recipients and HIV-negative/HCV-negative controls at both times. HIV/HCV coinfected recipients had worse PS compared with HIV-negative/HCV-infected controls (5-year: 67.0% versus 78.6%, P=0.007; 10-year: 29.3% versus 56.23%, P=0.002 [HR, 1.57; 95% CI, 1.11 to 2.22; P=0.01]). In conclusion, HIV-negative and HIV monoinfected kidney transplant recipients had similar GS and PS, whereas HIV/HCV coinfected recipients had worse outcomes. Although encouraging, these results suggest caution in transplanting coinfected patients.  相似文献   
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