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   19561篇
  免费   2388篇
  国内免费   400篇
耳鼻咽喉   143篇
儿科学   529篇
妇产科学   151篇
基础医学   3902篇
口腔科学   439篇
临床医学   2153篇
内科学   4079篇
皮肤病学   1268篇
神经病学   1108篇
特种医学   386篇
外国民族医学   1篇
外科学   1248篇
综合类   2190篇
预防医学   2294篇
眼科学   215篇
药学   993篇
  2篇
中国医学   663篇
肿瘤学   585篇
  2023年   610篇
  2022年   558篇
  2021年   658篇
  2020年   560篇
  2019年   613篇
  2018年   714篇
  2017年   402篇
  2016年   774篇
  2015年   1092篇
  2014年   1203篇
  2013年   1534篇
  2012年   902篇
  2011年   807篇
  2010年   827篇
  2009年   894篇
  2008年   737篇
  2007年   651篇
  2006年   601篇
  2005年   582篇
  2004年   1008篇
  2003年   482篇
  2002年   439篇
  2001年   372篇
  2000年   264篇
  1999年   291篇
  1998年   307篇
  1997年   383篇
  1996年   364篇
  1995年   331篇
  1994年   457篇
  1993年   324篇
  1992年   350篇
  1991年   346篇
  1990年   325篇
  1989年   227篇
  1988年   245篇
  1987年   128篇
  1986年   157篇
  1985年   163篇
  1984年   134篇
  1983年   88篇
  1982年   132篇
  1981年   96篇
  1980年   52篇
  1979年   41篇
  1978年   36篇
  1977年   30篇
  1976年   18篇
  1975年   16篇
  1973年   12篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
BackgroundThe association between systemic lupus erythematosus (SLE) and sarcoidosis has been considered as extremely rare. Most often, sarcoidosis coexists with Sjögren's syndrome. Researching the literature, it seems that the association of SLE and sarcoidosis is much more frequent than previously thought.Aim of the workWe present a case of a Serbian woman who was diagnosed with coexisting sarcoidosis and long-standing SLE.Case presentationThe 40 years old SLE patient was in long-standing remission on oral prednisolone (10 mg/day) and hydroxychloroquine (HCQ) (400 mg/day). She presented with fatigue, chest pain, and dry cough. Chest computerized tomography (CT) showed hilar and mediastinal lymphadenopathy. The biopsy had been performed and results showed sarcoidosis. Diagnosis has been confirmed: eosinophilic granulomas without central necrosis morphologically corresponding to chronic granulomatous lymphadenitis like sarcoidosis. Thereafter, the patient was hospitalized. No new symptoms appeared, and the physical examination was unremarkable. Serum calcium was elevated (2.75 mmol/l), anti-nuclear antibody (ANA), anti-double stranded deoxyribonucleic acid (anti-dsDNA) and anti-Ro antibodies were positive. Angiotensin converting enzyme (ACE) level was high normal (51 IU/L) and QuantiFERON-TB Gold test negative. The dose of prednisolone was increased to 40 mg/day with HCQ and the patient was discharged from hospital. On follow-up the patient improved with reduction of the steroid dose.ConclusionThe association of SLE and sarcoidosis should be considered even though it is reported to be extremely rare. May be the real incidence of these combinations is underestimated. More research about genetics and pathogenesis is needed to completely understand these conditions.  相似文献   
2.
Gonococcal infection is rarely associated with septic shock. We describe a recurrent case of septic shock related to disseminated gonococcemia in a patient with systemic lupus erythematosus and hypocomplementemic urticarial vasculitis, and discuss the implication of profound acquired complement deficiency secondary to these auto-immune diseases. This case raises the question of systematic antibioprophylaxis in patients with acquired complement deficiency.  相似文献   
3.
ObjectivesRecurrent Aphthous Stomatitis (RAS) a chronic idiopathic oral mucosal disease. But yet the etiology and pathogenesis of RAS are not exactly known, it is thought that inflammation play an important role in the pathogenesis. The aim of this study is to demonstrate the role of systemic inflammation among the possible etiological factors of RAS and to find the possible diagnostic correlation between Systemic Immune Inflammation Index (SII).MethodsPatients who were consulted the otolaryngology outpatient clinic and diagnosed with RAS between 2019–2021 were retrospectively analyzed. Neutrophil/Lymphocyte Ratio (NLR), Platelet/Lymphocyte Ratio (PLR) and SII values were calculated based on the results of complete blood count. Demographic and hematological parameters between control and RAS groups were compared. The statistical significance level was considered as <0.05.ResultsThere was no statistically significant difference between the control and RAS groups in terms of sex and age distributions (p = 0.566 and p = 0.173, respectively). SII, NLR and PLR values were significantly higher in the RAS group compared to the controls (p < 0.001, p < 0.001 and p = 0.001, respectively). A very strong correlation between SII and NLR, moderately strong correlation between SII and PLR and moderate correlation between NLR and PLR values were detected (respectively ρ: 0.813, 0.719, 0.532; p-values <0.001).ConclusionSII, NLR and PLR has significantly higher levels in the RAS group compared to the control group, that it supports the role of systemic inflammation in the etiopathogenesis of RAS. In addition, the results show that SII is a valuable marker for inflammation.Level of evidence4.  相似文献   
4.
5.
6.
目的探讨ω-3多不饱和脂肪酸(ω-3 poly unsaturated fatty acids,ω-3 PUFAs)对慢性移植物抗宿主病(chronic graft versus host disease,cGVH)狼疮模型小鼠的免疫调节功能影响。方法单次腹腔注射bm12小鼠淋巴细胞建立cGVH小鼠模型,造模当天分别给予90%ω-3 PUFAs和97%EPA灌胃治疗,持续14 d。通过流式细胞术检测小鼠脾脏淋巴细胞中各免疫指标,ELISA检测小鼠血清中总IgG水平。结果与正常对照组相比,cGVH组明显下调Treg亚群,明显上调TFH细胞、生发中心B细胞和浆细胞亚群;与模型对照组相比,90%ω-3和97%EPA均明显上调Treg亚群,并明显下调TFH细胞、生发中心B细胞和浆细胞亚群;且97%EPA组小鼠血清中总IgG水平明显下降。结论在cGVH狼疮小鼠模型中,ω-3 PUFAs通过增加Treg细胞,减少TFH细胞、生发中心B细胞和浆细胞,抑制IgG的分泌,从而发挥免疫抑制作用,且其免疫抑制作用可能与ω-3 PUFAs含量相关。  相似文献   
7.
8.
9.
目的:对食管胃结合部腺癌近端胃切除术(PG)人工三角瓣成形后残胃食糜进行流体动力学数值模拟,并计算不同性质胃内食糜的流动特征。方法:构建常规PG和人工三角瓣成形术术后胃仿真模型,运用Fluent软件对不同粘度胃内食糜反流问题进行数值模拟。结果:站立位姿态时,相对常规PG方案,人工三角瓣成形手术方案表现出较好的抗反流作用;卧位姿态时,当胃内食糜粘度大于0.145 2 Pa[?s,且胃内食糜不超过人工三角瓣情况下,人工三角瓣成形抗反流手术表现出较好的抗反流效果;人工三角瓣抗反流成形手术方案数值模拟结果与临床上患者表现一致。结论:本研究仿真分析为人工三角瓣成形抗反流手术方案的有效性机理分析、临床患者术后饮食及手术方案的进一步改进提供理论及数值依据。 【关键词】食管胃结合部腺癌;抗反流;人工三角瓣;计算流体力学  相似文献   
10.
采用Mimics对心脏进行三维重构,用3-matic进行模型优化以及模型误差分析,对左心室室壁运动做速度分布假设,基于UDF宏文件对左心室室壁运动编写程序,将血液视为非牛顿流体,采用动网格技术研究不同血压对左心室血液流动的影响。模拟发现当左心室收缩时,压力梯度明显,内部压力减小。当左心室舒张时,内部压力逐渐增高。二尖瓣口处的速率先增大后减小。血压升高,左心室内剪切应力持续增大,极易破坏红细胞结构,产生溶血现象,导致心脏功能紊乱。  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