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   167406篇
  免费   16642篇
  国内免费   10018篇
耳鼻咽喉   1401篇
儿科学   2186篇
妇产科学   1794篇
基础医学   22968篇
口腔科学   2776篇
临床医学   19985篇
内科学   21374篇
皮肤病学   1809篇
神经病学   7513篇
特种医学   5990篇
外国民族医学   65篇
外科学   15648篇
综合类   31029篇
现状与发展   31篇
一般理论   12篇
预防医学   12681篇
眼科学   3729篇
药学   19719篇
  164篇
中国医学   10869篇
肿瘤学   12323篇
  2024年   464篇
  2023年   2378篇
  2022年   4628篇
  2021年   8280篇
  2020年   6183篇
  2019年   5209篇
  2018年   5445篇
  2017年   5276篇
  2016年   4876篇
  2015年   7372篇
  2014年   9236篇
  2013年   9402篇
  2012年   13101篇
  2011年   13974篇
  2010年   10370篇
  2009年   8543篇
  2008年   9929篇
  2007年   9759篇
  2006年   8801篇
  2005年   7743篇
  2004年   5894篇
  2003年   5593篇
  2002年   4679篇
  2001年   3960篇
  2000年   3358篇
  1999年   2758篇
  1998年   1678篇
  1997年   1803篇
  1996年   1275篇
  1995年   1208篇
  1994年   1101篇
  1993年   772篇
  1992年   970篇
  1991年   890篇
  1990年   791篇
  1989年   727篇
  1988年   651篇
  1987年   556篇
  1986年   526篇
  1985年   430篇
  1984年   369篇
  1983年   305篇
  1982年   270篇
  1981年   229篇
  1980年   196篇
  1979年   198篇
  1978年   192篇
  1977年   210篇
  1976年   191篇
  1974年   154篇
排序方式: 共有10000条查询结果,搜索用时 69 毫秒
31.
目的探讨腹腔镜经腹腹膜前疝修补术(TAPP)放置腹膜前引流对术后血肿及血清肿的影响。 方法选取2016年6月至2018年5月,江苏省苏州市中西医结合医院收治的单侧腹股沟疝患者90例,随机分为试验组和对照组,2组患者均行TAPP手术。试验组放置腹膜前引流管,对照组不放置引流管。收集2组患者的一般资料、手术相关资料及随访资料进行统计学分析,对比2组患者术后血肿及血清肿发生率差异。 结果全部患者均完成手术及随访。2组患者的一般资料、疝位置、疝分型、手术时间、住院花费、术后住院时间差异无统计学意义(P>0.05)。2组患者的术后发热发生率、急性疼痛发生率差异无统计学意义(P>0.05)。试验组术后血肿发生率明显低于对照组(P<0.05),试验组患者术后1和3个月血清肿发生率明显低于对照组,差异有统计学意义(P<0.05)。2组患者1年随访均观察到1例复发的病例,差异无统计学意义(P>0.05);随访期内2组患者均未出现感染的病例。 结论TAPP中,放置腹膜前引流管能够有效降低患者术后血肿和血清肿的发生率,同时并不增加感染和复发风险。  相似文献   
32.
Pharmaceutical Chemistry Journal - Three extracts were produced from the above-ground part of the meadowsweet Filipendula ulmaria (L.) Maxim. using water, 40% ethanol, and 70% ethanol. Comparative...  相似文献   
33.
Abstract

Objective

The sex, age, medical history, treatment, tobacco use, race risk (SAMe-TT2R2) Score; the sex, age, medical history, treatment, tobacco use, genotype combination (SAMe-TT2G2) Score; and the so-called modified SAMe-TT2R2 scores have been proposed to predict the anticoagulation quality for patients with non-valvular atrial fibrillation (NVAF). The data from a prospective controlled study is used to validate the SAMe-TT2R2 and SAMe-TT2G2 scores in Chinese NVAF patients treated with warfarin and to evaluate the association of factors with time in therapeutic range (TTR) to predict the quality of oral anticoagulation control.  相似文献   
34.
35.
European Archives of Oto-Rhino-Laryngology - Several polymorphisms in a disintegrin and metalloproteinase 33 (ADAM33) have been implicated in susceptibility to allergic rhinitis (AR), but the...  相似文献   
36.
BACKGROUNDGuillain-Barré syndrome (GBS) is a rare disorder that typically presents with ascending weakness, pain, paraesthesias, and numbness, which mimic the findings in lumbar spinal stenosis. Here, we report a case of severe lumbar spinal stenosis combined with GBS.CASE SUMMARYA 70-year-old man with a history of lumbar spinal stenosis presented to our emergency department with severe lower back pain and lower extremity numbness. Magnetic resonance imaging confirmed the diagnosis of severe lumbar spinal stenosis. However, his symptoms did not improve postoperatively and he developed dysphagia and upper extremity numbness. An electromyogram was performed. Based on his symptoms, physical examination, and electromyogram, he was diagnosed with GBS. After 5 d of intravenous immunoglobulin (0.4 g/kg/d for 5 d) therapy, he gained 4/5 of strength in his upper and lower extremities and denied paraesthesias. He had regained 5/5 of strength in his extremities when he was discharged and had no symptoms during follow-up.CONCLUSIONGBS should be considered in the differential diagnosis of spinal disorder, even though magnetic resonance imaging shows severe lumbar spinal stenosis. This case highlights the importance of a careful diagnosis when a patient has a history of a disease and comes to the hospital with the same or similar symptoms.  相似文献   
37.
目的 总结国产封堵器经皮和经胸途径治疗先天性心脏病的临床疗效。方法 回顾性分析我院2013年1月至2017年12月在X线透视下或单纯超声心动图引导下采用经皮穿刺股静脉或股动静脉法,或者食管超声心动图监测下经胸小切口行先天性心脏病封堵1186例,其中经皮X线下封堵1081例、经皮单纯超声引导下封堵42例、经胸封堵63例;其中动脉导管未闭( patent ductus arteriole,PDA)426例、房间隔缺损(atrial septal defect,ASD)363例、室间隔缺损(ventricular septal defect,VSD)348例、卵圆孔未闭11例、房间隔缺损合并室间隔缺损9例、房间隔缺损合并动脉导管未闭6例、房间隔缺损合并肺动脉瓣狭窄(pulmonary stenosis,PS)12例、动脉导管未闭合并肺动脉瓣狭窄8例、主肺动脉侧支封堵3例[经胸封堵66例改为63例,PDA443例改为426例]。结果 全组病例成功率98.2%(1165/1186),无死亡病例。随访1~36个月,术后第1、3、6、12个月及术后每年常规行超声心动图及心电图检查。术后第1、6、12个月的随访率分别为 92.9%(1102/1186)、84.1%(998/1186)、70.5%(836/1186)。超声心动图提示少量残余分流(<3 mm)18例;三尖瓣少量反流33例,中量反流5例;主动脉瓣轻度反流5例,中度反流1例;心律失常Ⅲ°房室传导阻滞(Avionics Bulletin,AVB[房室传导阻滞(Avionics Bulletin,AVB)])1 例,Ⅱ°AVB 3例,完全性左束支3例,交界性心动过速3例,交界性逸搏2例。结论 国产封堵器在先天性心脏病封堵治疗中具有成功率高、创伤小、并发症低、操作容易、疗效确切、恢复快等特点,是治疗先天性心脏病的理想方法。  相似文献   
38.
Objective: To assess the effect of electroacupuncture(EA) on expression of cytoskeletal proteins from Sertoli cells(SCs) and spermatogenesis in rats with oligozoospermia of insufficiency of Shen(Kidney)essence syndrome(OIKES).Methods: Twenty healthy male Sprague-Dawley rats were randomly assigned to four groups using a random number table: control,tripterygium glycosides(TG) treatment,sham and EA groups(n=5 in each group).A rat model of OIKES was established by oral gavage with TG.The EA group was treated with TG and received EA at Shenshu(BL 23) and Zusanli(ST 36) acupoints for 20 min,once daily for 30 days,while the sham group received EA at identical acupoints with skin penetration without stimulation.After 30 days,the ?nal body weight and coef?cients for the testis and epididymis were calculated and sperm parameters were measured.Immunohistochemical analyses were performed to detect expression of vimentin and α-tubulin in SCs and proliferating cell nuclear antigen(PCNA) immunoreactivity in germ cells.Apoptosis in germ cells was quanti?ed by the transferase biotin-dUTP nick end labeling assay.Results: Compared with the control group,the final body weight and testis/epididymis coefficients of rats in the TG-treated group were not significantly different,but the sperm count and motility were lower(P0.05).Expressions of vimentin and α-tubulin were also signi?cantly weaker(P0.01).The PCNA immunoreactivity of germ cells was decreased(P=0.059),whereas the apoptotic index of germ cells was increased signi?cantly(P0.01).In contrast,EA at BL 23 and ST 36 acupoints signi?cantly improved the ?nal body weight as well as the sperm count,concentration and motility(P0.01 or P0.05).EA increased expression of vimentin and α-tubulin in SCs markedly,and signi?cantly enhanced PCNA immunoreactivity with decreased apoptosis in germ cells(P0.01 or P0.05).Conclusions: EA at BL 23 and ST 36 acupoints has protective effects on spermatogenesis in rats with OIKES.This effect seems to be achieved by attenuating TG-induced disruption of cytoskeletal protein in SCs.  相似文献   
39.
40.
目的研究和开发支持中医和现代生物医学本体和术语集的语义标注系统。方法以MedPortal本体库和中医临床术语集等为术语资源库,设计语义标注系统工作流程和功能框架,并开发Web应用系统。结果构建了一个基于Web的中医药文献语义标注系统,支持语料库管理与维护、术语词典管理、语义标注和语义检索等功能,既可以为基于机器学习的信息抽取算法研究提供训练集,又能实现语义层面的多来源数据集成与知识融合。结论该中医药文献语义标注系统设计方案已经过实际项目验证,可为其他同类系统研发提供参考。  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