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   31799篇
  免费   2158篇
  国内免费   451篇
耳鼻咽喉   144篇
儿科学   833篇
妇产科学   557篇
基础医学   1806篇
口腔科学   915篇
临床医学   4144篇
内科学   5614篇
皮肤病学   594篇
神经病学   1001篇
特种医学   811篇
外科学   2897篇
综合类   3750篇
现状与发展   6篇
预防医学   7058篇
眼科学   328篇
药学   2218篇
  27篇
中国医学   734篇
肿瘤学   971篇
  2024年   45篇
  2023年   528篇
  2022年   788篇
  2021年   1366篇
  2020年   1644篇
  2019年   1236篇
  2018年   1253篇
  2017年   1105篇
  2016年   1168篇
  2015年   1122篇
  2014年   2257篇
  2013年   2926篇
  2012年   1968篇
  2011年   2045篇
  2010年   1664篇
  2009年   1456篇
  2008年   1452篇
  2007年   1455篇
  2006年   1407篇
  2005年   1167篇
  2004年   954篇
  2003年   852篇
  2002年   690篇
  2001年   561篇
  2000年   454篇
  1999年   413篇
  1998年   350篇
  1997年   287篇
  1996年   279篇
  1995年   218篇
  1994年   160篇
  1993年   170篇
  1992年   142篇
  1991年   96篇
  1990年   107篇
  1989年   80篇
  1988年   86篇
  1987年   59篇
  1986年   50篇
  1985年   63篇
  1984年   53篇
  1983年   35篇
  1982年   42篇
  1981年   41篇
  1980年   35篇
  1979年   14篇
  1978年   10篇
  1977年   16篇
  1976年   13篇
  1975年   10篇
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
81.
While systemic autoimmune diseases are the main possibilities in the differential diagnosis of scleritis, other less common etiologies such as infections must also be considered. The authors report four cases of infectious scleritis to review predisposing factors, clinical characteristics, methods of diagnostic approach, and response to therapy. Two patients had primary scleritis and two patients had secondary scleritis following extension of primary corneal infection (corneoscleritis). Diagnoses included three local infections (one each withStaphylococcus. Acanthamoeba, and herpes simplex) and one systemic infection (Lyme disease). Stains, cultures, or immunologic studies from scleral, conjunctival, and/or corneal tissues, and serologic tests were used to make the diagnosis. Medical therapy, including antimicrobial agents, was instituted in all patients, and surgical procedures were additionally required in two patients (scleral grafting in one and two penetrating keratoplasties in another); the patient who required two penetrating keratoplasties had corneoscleritis and underwent eventual enucleation. Infectious agents should be considered in the differential diagnosis of scleritis.  相似文献   
82.
The author describes his surgical approach to the problems of the aging upper arm and elbow region. Surgery at an appropriate age can prevent the progressive wrinkling of the elbow which is further aggravated by aging of the upper arm. The author's operation is aimed at correcting both portions of the arm anatomy at the same time.  相似文献   
83.
84.
几丁糖预防术后腹腔粘连的实验研究   总被引:1,自引:1,他引:0  
目的探讨几丁糖对术后腹腔粘连的预防作用.方法将45只大鼠随机分为A、B、C 3组,于腹腔内浆膜损伤部位分别注入1%乳酸液、32%右旋糖酐-70液和2%几丁糖乳酸液各2 ml,术后14 d处死动物,观察各组腹腔粘连状况.结果 3组粘连分级比较有显著性差异(P<0.01),C组粘连发生率与另2组有显著差异(P<0.05).光镜下C组炎症反应轻微,纤维增生不明显;电镜下C组纤维细胞分泌胶原能力弱,间皮细胞增生活跃.结论几丁糖可有效降低大鼠术后腹腔粘连的发生和粘连程度,其作用优于右旋糖酐-70,且不影响切口的愈合.  相似文献   
85.
目的 总结我市结核病控制项目实施效果和经验。方法 根据全市各县(区)上报的结核病报表和有关总结材料进行分析。结果 在项目实施期间发现涂阳病人7522例,治愈了7303例,涂阳病人登记率从1993年的8.2/10万提高到2001年的39.4/10万,初、复治涂阳病人治愈率从1992年的80.0%和81.8%提高到2001年的98.9%和96.2%。结论 我市结核病控制项目实施效果显,项目所取得的成功经验和技术策略对今后结核病控制可持续发展有着重要的指导作用。  相似文献   
86.
Objectives and design: The aim of this study was to investigate whether the exposure of mast cells (MCs) to bacterial components affects the expression of Toll-like receptor (TLR) 4, and to elucidate the behavior of MCs during the early response to infection. Materials: Two human MC lines, HMC-1 and LAD2, were employed. Messenger RNA expression was observed by RT and real-time PCR. TLR4 expression was determined by Western blotting. TNF-α secretion was analyzed with ELISA. The degranulation ratio was measured with betahexosaminidase assay. Results: Although bacterial components increased TLR4 mRNA, only lipopolysaccharide (LPS) augmented the TLR4 protein expression. LAD2 pre-treated with LPS for 8 h resulted in 2-fold increased TNF-α secretion on LPS restimulation. Conclusion: These results suggest that the exposure of MCs to LPS may reinforce the innate immune system due to up-regulation of MC TLR4, followed by increased TNF-α release. Received 20 April 2006; returned for revision 14 July 2006; accepted by G. Wallace 11 August 2006  相似文献   
87.
OBJECTIVE: To explore pregnancy outcome in HIV-1-positive and HIV-negative women, and mother-to-child transmission (MTCT) according to mode of delivery under effective highly active antiretroviral therapy (HAART). DESIGN: Cohort of 143 pregnant HIV-1-infected women including a matched case-control study in a 2:1 ratio of controls to cases (n=98). SETTING: Academic Medical Center in Amsterdam and Erasmus Medical Center in Rotterdam, the Netherlands. POPULATION: Consecutive referred HIV-1 infected pregnant women treated with HAART and matched control not infected pregnant women. MAIN OUTCOME MEASURES: MTCT, preterm delivery, low birthweight, pre-eclampsia. RESULTS: MTCT was 0% (95% CI 0-2.1%). Seventy-eight percent of HIV-1-infected women commenced and 62% completed vaginal delivery. The calculated number of caesarean sections needed to prevent a single MTCT was 131 or more. Preterm delivery rates were 18% (95% CI 11-27) in women infected with HIV-1 and 9% (95% CI 5-13) in controls (P=0.03). HAART used at <13 weeks of gestation was associated with a 44% preterm delivery rate compared with 21% when HAART was started at or after 13 weeks and 14% in controls. (Very) low birthweight and incidence of pre-eclampsia were not different between HIV-1 and controls. CONCLUSIONS: We have not demonstrated any MTCT after vaginal delivery in women effectively treated by HAART. The HAART-associated increase in preterm delivery rate is mainly seen after first trimester HAART use.  相似文献   
88.
临床输液反应的分析与预防   总被引:1,自引:0,他引:1  
目的对临床发生的输液反应进行分析,找出发生的原因,探讨预防措施。方法:对30例输液反应资料进行分析。结果:以热原反应最为多见,占76.67%,而过敏反应,占16.67%,局部反应,占6.67%。结论:严格执行消毒制度,遵守无菌操作规程,把好药品和输液器具质量关,合理用药,注意配伍等是减少临床输液反应的关键。  相似文献   
89.
胃幽门弯曲菌感染对胃癌发生影响的探讨   总被引:1,自引:1,他引:0  
应用Warthin-starry镀银技术检查胃幽门弯曲菌,对中国胃癌高发区及美国胃癌高发区新奥尔良检查了300例具有胃症状的胃粘膜标本。结果发现幽门弯曲菌阳性率为60~62%,并且看到这种细菌的感染与慢性胃炎病变的程度有明显的关系。本文探讨了幽门弯曲菌的感染与胃癌癌前病变的关系。  相似文献   
90.
子宫内膜癌为女性生殖道三大恶性肿瘤之一。子宫内膜增生症(endometrial hyperplasia,EH)乃子宫内膜癌的癌前病变,因而早期诊断和治疗EH非常必要。中医药防治EH相关子宫内膜癌有其应用简便、价格低廉、有效安全等优势,符合中医"治未病"的思想。由此推理,中医药防治EH相关子宫内膜癌有着广阔前景,值得深入研究。  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