首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   81558篇
  免费   7408篇
  国内免费   2281篇
耳鼻咽喉   652篇
儿科学   1871篇
妇产科学   637篇
基础医学   5093篇
口腔科学   533篇
临床医学   12562篇
内科学   17821篇
皮肤病学   508篇
神经病学   4493篇
特种医学   3511篇
外国民族医学   2篇
外科学   7750篇
综合类   15393篇
预防医学   5212篇
眼科学   944篇
药学   7880篇
  108篇
中国医学   4930篇
肿瘤学   1347篇
  2024年   104篇
  2023年   1270篇
  2022年   2248篇
  2021年   3563篇
  2020年   3751篇
  2019年   2712篇
  2018年   2471篇
  2017年   3101篇
  2016年   3044篇
  2015年   2840篇
  2014年   5627篇
  2013年   5471篇
  2012年   4702篇
  2011年   4995篇
  2010年   4208篇
  2009年   4029篇
  2008年   4090篇
  2007年   4333篇
  2006年   3960篇
  2005年   3326篇
  2004年   2661篇
  2003年   2363篇
  2002年   2001篇
  2001年   1868篇
  2000年   1552篇
  1999年   1317篇
  1998年   1028篇
  1997年   938篇
  1996年   786篇
  1995年   878篇
  1994年   761篇
  1993年   575篇
  1992年   628篇
  1991年   508篇
  1990年   430篇
  1989年   378篇
  1988年   360篇
  1987年   345篇
  1986年   262篇
  1985年   291篇
  1984年   268篇
  1983年   165篇
  1982年   203篇
  1981年   131篇
  1980年   113篇
  1979年   124篇
  1978年   136篇
  1977年   68篇
  1976年   86篇
  1975年   55篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.  相似文献   
3.
4.
5.
6.
PurposeTo create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE).Materials and MethodsFluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4–6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4–6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75–250-μm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest.ResultsThe mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed.ConclusionsA nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.  相似文献   
7.
von Willebrand factor (VWF) plays a crucial role in hemostasis and thrombosis. VWF is involved in platelet attachment to the subendothelium, serving as a carrier protein for coagulation factor VIII. In this study, myocardial tissues from deceased patients with ischemic heart disease and a mouse model of acute myocardial infarction were subjected to immunohistochemistry to determine VWF expression. We examined 28 neutral formalin-fixed, paraffin-embedded myocardial tissue samples obtained from the autopsies of patients who were diagnosed with ischemic heart disease within 48 h postmortem. Most myocardial cells were negative for VWF, although some cells showed nonspecific positivity. Elevated VWF expression was observed around myocardial cells undergoing remodeling, suggesting that endothelial proliferation occurred at these sites. In contrast, completely fibrotic myocardial foci did not show upregulated VWF expression. Positivity in fibrin deposition and hemorrhagic sites was observed. The same VWF expression characteristics as those observed in the human samples were observed in the mouse model. VWF immunostaining as an endothelial marker may be a useful supplementation to conventional staining techniques that are currently used in the diagnosis of ischemic heart disease in terms of examining the timing of myocardial remodeling in detail and highlighting the remodeling process.  相似文献   
8.
9.
10.
目的分析瘀热型慢性前列腺炎(CP)临床症状与心理性因素及性功能的相关性。方法收集2020年6月至2021年6月在南京市江宁中医院泌尿外科门诊诊治的91例瘀热型CP患者的临床资料进行回顾性分析,使用美国国立卫生研究院慢性前列腺炎症状指数评分表(NIH-CPSI)、中医证候量表、7项广泛性焦虑障碍量表(GAD-7)、抑郁症筛查量表(PHQ-9)、疼痛灾难化量表(PCS)、国际勃起功能评分表(IIEF-5)和早泄诊断量表(PEDT)对患者进行评估,对量表评定结果进行Pearson相关性分析和多元线性回归分析。结果(1)症状量表:NIH-CPSI总分与中医量表总分、GAD-7总分呈正相关,中医证候量表总分与CPSI、GAD-7、PHQ-9、PCS、PEDT总分呈正相关(P<0.05);CPSI总分随中医量表总分递增而升高,中医证候量表总分随CPSI疼痛症状、PHQ-9总分递增而升高(P<0.05)。(2)情绪量表:GAD-7总分与CPSI、中医证候量表总分、排尿症状、PHQ总分、PEDT总分呈正相关,PHQ-9总分与中医证候量表总分、疼痛及排尿症状、PCS总分、PEDT总分呈正相关,PCS总分与中医证候量表总分及疼痛症状分值呈正相关(P<0.05);GAD-7总分随PHQ-9总分递增而升高;PHQ-9总分随中医证候量表排尿症状、GAD-7、PCS分值递增而升高;PCS总分随中医证候量表疼痛症状、PHQ-9分值递增而升高(P<0.05)。(3)性功能量表:IIEF-5总分与中医证候量表疼痛分值呈负相关,PEDT总分与中医证候量表总分及疼痛症状、GAD-7、PHQ-9分值呈正相关(P<0.05);IIEF-5总分随中医证候量表疼痛症状分值递减而升高(P<0.05)。结论瘀热型CP患者表现为以疼痛为主,伴随排尿异常、情绪异常、认知障碍和性功能障碍的系列症状,同时使用中医证候量表及CPSI评估能较好的反映其病情的严重程度。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号