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   22632篇
  免费   1974篇
  国内免费   404篇
耳鼻咽喉   142篇
儿科学   793篇
妇产科学   99篇
基础医学   2961篇
口腔科学   315篇
临床医学   2161篇
内科学   6111篇
皮肤病学   469篇
神经病学   800篇
特种医学   485篇
外科学   2603篇
综合类   2709篇
现状与发展   5篇
预防医学   602篇
眼科学   463篇
药学   2164篇
  7篇
中国医学   1993篇
肿瘤学   128篇
  2024年   40篇
  2023年   544篇
  2022年   639篇
  2021年   1018篇
  2020年   984篇
  2019年   964篇
  2018年   966篇
  2017年   1001篇
  2016年   876篇
  2015年   788篇
  2014年   1436篇
  2013年   2461篇
  2012年   1083篇
  2011年   1243篇
  2010年   908篇
  2009年   1041篇
  2008年   964篇
  2007年   1095篇
  2006年   874篇
  2005年   761篇
  2004年   644篇
  2003年   465篇
  2002年   486篇
  2001年   390篇
  2000年   344篇
  1999年   330篇
  1998年   330篇
  1997年   242篇
  1996年   250篇
  1995年   215篇
  1994年   199篇
  1993年   176篇
  1992年   152篇
  1991年   111篇
  1990年   116篇
  1989年   89篇
  1988年   75篇
  1987年   84篇
  1986年   84篇
  1985年   75篇
  1984年   74篇
  1983年   47篇
  1982年   78篇
  1981年   67篇
  1980年   33篇
  1979年   40篇
  1978年   32篇
  1977年   24篇
  1976年   24篇
  1975年   16篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
81.
特发性身材矮小儿童成骨细胞的功能状况   总被引:2,自引:2,他引:0  
目的通过检测特发性身材矮小(ISS)儿童血清骨碱性磷酸酶(BAP)及骨钙蛋白(OC)水平,探讨其成骨细胞的功能状况。方法ISS组36例及健康对照组儿童50例。ISS组分为青春期前组及青春期组。测各组儿童身高、体质量、体质量指数,采用CHN法评定左侧手、腕部骨化指标,计算骨龄。采用ELISA法测其血清BAP及OC水平。结果青春期前,ISS儿童血清BAP及OC水平为(79.90±25.96)U/Lvs(60.96±18.46)μg/L,健康对照组为(152.17±35.36)U/Lvs(76.16±28.03)μg/L;青春期,ISS儿童血清BAP及OC水平为(108.33±35.20)U/Lvs(63.82±24.81)μg/L,健康对照组为(156.30±35.29)U/Lvs(104.92±28.26)μg/L。青春期前及青春期ISS组血清BAP及OC水平均明显低于健康对照组,存在显著性差异(Pa<0.01)。结论ISS儿童以成骨细胞为中心环节的骨塑造和再造能力均较健康生长发育少年儿童差。  相似文献   
82.
检查30例关节炎患者的关节液,结果示类风湿性关节炎患者关节液中白细胞数为330~72600/mm~3,粒细胞为9~97%,结合关节液的其它物理性质,对类风湿关节炎的诊断有一定参考价值。并观察到类风湿关节炎患者血清中IgG、IgA、IgM和关节液中IgG高于其它类型关节炎。  相似文献   
83.
SUMMARY: Renal involvement is not uncommon in rheumatoid arthritis (RA). Many RA patients have renal dysfunction either secondary to the drugs used to treat arthritis or because of the chronic inflammation. Renal pathologies have often included amyloidosis, drug-related renal disease and mesangial glomerulonephritis. However, membranoproliferative glomerulonephritis has only been rarely reported. We report a case of rheumatoid arthritis associated with membranoproliferative glomerulonephritis that rapidly progressed to end-stage renal disease.  相似文献   
84.
85.
86.
82例高血压患者16项人格特质测验   总被引:1,自引:0,他引:1  
研究目的应用卡特尔16项人格特质测验探讨原发性高血压患者的人格特征。研究背景高血压病是危害人类健康的常见病之一,发病率逐年上升,但其病因至今尚未阐明,故有必要从心理、人格方面来探讨高血压的发病原因,以利于高血压病的防治。研究方法本文对82例均由2名以上内科医师确诊为原发性高血压、且现在高压仍保持在20/12.7kPa以上的患者进行卡特尔16项人格特质测验,并与78例人群对照分析。结果高血压患者在C-稳定性、E-峙强性、Q-紧张性以及在双重人格因素类型中的适应与焦虑方面与正常对照组有显著差异(P<0.05)。结论心理-社会因素是促使高血压发生的重要因素,它对高血压病因的阐明有重要意义,同时也使我们越来越重视运用心理、行为疗法,如生物反馈、各种松驰疗法等去防治高血压。  相似文献   
87.
带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎   总被引:1,自引:0,他引:1  
目的:阐明带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎的疗效。材料和方法:对42例48髋晚期类风湿性髋关节炎病人采用以旋股外侧血管降支为蒂的股前外侧筋膜瓣移植行患髋成形术。结果:术后随访4~10.5年,平均4.5年,髋关节活动范围术前平均16.5°,术后228.6°,按照Charnley和吴之康人工髋关节置换术后的疗效评定标准,优良29髋、很好13髋、好6髋,尚可、差、很差无。结论:患者年龄在15~40岁之间为合适的治疗年龄。与人工髋关节置换术相比,本方法对髋关节正常结构破坏小;一旦手术失败仍可选用其它治疗方法弥补;且并发症少、费用低、远期效果好。  相似文献   
88.
Manganese (Mn) exposure can cause parkinsonism. Pathological changes occur mostly in the pallidum and striatum. Two patients with a long history of occupational Mn exposure presented with Mn-induced parkinsonism. In one patient, magnetic resonance imaging (MRI) showed findings consistent with Mn exposure, and Mn concentration was increased in the blood and urine. However, this patient's clinical features were typical of idiopathic Parkinson disease (PD). Previous pathological and positron emission tomography studies indicate that striatal dopamine transporter density is normal in Mn-induced parkinsonism, whereas it is decreased in PD. Therefore, we performed [(123)I]-(1r)-2 beta-carboxymethoxy-3beta-(4-iodophenyl)tropane ([(123)I]-beta-CIT) single-photon emission computed tomography. Severe reduction of striatal beta-CIT binding was indicated, which is consistent with PD. We propose three interpretations: (1) the patients have PD, and Mn exposure is incidental; (2) Mn induces selective degeneration of presynaptic dopaminergic nerve terminals, thereby causing parkinsonism; or (3) Mn exposure acts as a risk of PD in these patients. Our results and careful review of previous studies indicate that the axiom that Mn causes parkinsonism by pallidal lesion may be over-simplified; Mn exposure and parkinsonism may be more complex than previously thought. Further studies are required to elucidate the relationship between Mn and various forms of parkinsonism.  相似文献   
89.
养阴清热、宣痹通络法治疗类风湿性关节炎的临床研究   总被引:5,自引:0,他引:5  
目的 观察清络通痹颗粒治疗类风湿性关节炎阴虚络热证的临床疗效。方法 将118例患者随机分为清络通痹颗粒治疗组63例和雷公藤多甙片对照组55例,观察用药前后主要症状、体征和实验室检测指标的变化。结果 治疗组的临床治愈率为9.52%,临床治愈显效率为38.10%,总有效率为90.48%,疗效明显优于对照组的0%、20%、83.64%(P<0.05);治疗组的类风湿因子滴度、血沉、C反应蛋白、免疫球蛋白也明显降低,与对照组相比差异显著(P<0.05或P<0.01)。结论 清络通痹颗粒具有抗炎镇痛、调节免疫紊乱等作用,从而达到控制病情的治疗效果。  相似文献   
90.
Objective. To evaluate the impact of chronic inflammation on lipoprotein lipase (LPL) levels and triglyceride metabolism in patients with rheumatoid arthritis (RA). Design. Plasma levels of LPL activity and mass before and after heparin were determined in post-menopausal women with active RA and in controls. The results were related to lipid levels and inflammatory variables. The LPL activity and mass together with triglyceride levels were also measured before and 6 h after an oral fat load. Setting. The study was performed on in- and out-patients at a University Rheumatology clinic. The controls came from the same reference area. Subjects. Altogether 17 consecutive post-menopausal female patients with RA and 16 age and sex matched controls were enrolled for the initial determination of LPL. Fifteen of the patients and 15 of the controls agreed to take part in the fat load. Of these, one patient and one control were excluded. Main outcome measures. LPL determination: basal levels and post-heparin levels of LPL activity and mass. Correlations between LPL and blood lipids (cholesterol, triglycerides), lipoprotein levels (high density lipoprotein, HDL; low density lipoprotein, LDL), erythrocyte sedimentation rate (ESR) acute phase proteins (orosomucoid, haptoglobin, fibrinogen mass) and cytokines (tumour necrosis factor α, TNF-α; interleukin 1β, IL-1β; and interleukin-6, IL-6). Fat tolerance test: LPL activity, mass and triglyceride levels before and 6 h after a per oral fat load. Results. Pre-heparin LPL mass (P<0.01) and activity (P<0.01) were significantly lower in the rheumatoid patients. Pre-heparin LPL mass showed no correlation to the lipid levels, but an inverse correlation to several inflammatory parameters; it was significant for orosomucoid (rs=?0.63, P<0.05) and C-reactive protein (CRP) (rs=?0.54, P<0.05) and close to significant for haptoglobin (rs=?0.48, P=0.087) and IL-6 (rs=?0.52, P=0.061). Six hours after a lipid load the LPL activity and mass were significantly lower in RA (P<0.05 and P<0.01, respectively) but the triglyceride level was not significantly different compared to controls. Conclusion. An inverse relationship exists between inflammatory status and pre-heparin LPL mass. Pre-heparin LPL mass reflects mainly the inactive monomeric fraction of LPL. This has been shown to hinder the uptake of remnant lipoprotein particles through competition with lipoprotein bound dimeric LPL for the LDL receptor-related protein (LRP receptor) on hepatocytes and macrophages in culture. A decrease of the level of monomeric LPL in plasma may thus be beneficial for remnant catabolism. The same mechanism may on the other hand increase macrophage uptake of lipids. This may not affect global lipid metabolism but may be important in driving the atherosclerotic process in the vessel wall.  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