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   56778篇
  免费   4637篇
  国内免费   199篇
耳鼻咽喉   513篇
儿科学   1554篇
妇产科学   1095篇
基础医学   7513篇
口腔科学   990篇
临床医学   6320篇
内科学   10933篇
皮肤病学   814篇
神经病学   4863篇
特种医学   2308篇
外科学   9397篇
综合类   792篇
一般理论   57篇
预防医学   5606篇
眼科学   1264篇
药学   4091篇
  2篇
中国医学   53篇
肿瘤学   3449篇
  2023年   325篇
  2022年   455篇
  2021年   1159篇
  2020年   655篇
  2019年   1090篇
  2018年   1315篇
  2017年   960篇
  2016年   1036篇
  2015年   1243篇
  2014年   1816篇
  2013年   2516篇
  2012年   3809篇
  2011年   3899篇
  2010年   2124篇
  2009年   1888篇
  2008年   3398篇
  2007年   3678篇
  2006年   3552篇
  2005年   3445篇
  2004年   3183篇
  2003年   3030篇
  2002年   2863篇
  2001年   885篇
  2000年   845篇
  1999年   845篇
  1998年   685篇
  1997年   569篇
  1996年   540篇
  1995年   558篇
  1994年   461篇
  1993年   431篇
  1992年   545篇
  1991年   497篇
  1990年   511篇
  1989年   481篇
  1988年   455篇
  1987年   395篇
  1986年   398篇
  1985年   442篇
  1984年   376篇
  1983年   309篇
  1982年   264篇
  1981年   240篇
  1980年   223篇
  1979年   243篇
  1978年   238篇
  1977年   193篇
  1974年   210篇
  1973年   195篇
  1972年   188篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
121.
122.
BACKGROUND: Stem cell transplant recipients are susceptible to pulmonary infections, including influenza A. Typically, isolated influenza pneumonia has a diffuse, interstitial infiltrate pattern. OBJECTIVES: To describe the unusual clinical and radiographic course of influenza A pneumonia in a stem cell transplant recipient. STUDY DESIGN: Case report in which microbiologic assays, bronchoscopic and pathologic specimens are obtained. RESULTS: We describe a patient with influenza A pneumonia 8 months following a peripheral blood stem cell transplant who presented with minimal respiratory symptoms and rapidly progressing, focal pulmonary infiltrates. The large size and appearance of the masses have not been reported before in a patient with isolated influenza. CONCLUSION: This case highlights the differences of presentation and importance of early diagnosis and treatment of immunocompromised patients infected with influenza.  相似文献   
123.
The objective of this study was to develop and verify a new technique for monitoring the progression of osteoarthritis (OA) by combining a rat model with the imaging modality optical coherence tomography (OCT). Time-sequential, in vivo, OCT imaging was performed on the left femoral condyles of 12 Wistar rats following sodium-iodoacetic acid-induced OA progression. The right femoral condyles (untreated) were also imaged and served as controls. Imaging was performed on days 0, 10, 20, 30, and 60 with an OCT system capable of acquiring images at four frames per second and an axial resolution of 5 microm. Progressive changes were analyzed using an OA scoring system. OCT successfully identified progressive cartilage degeneration as well as alteration of the cartilage/bone interface. Significant changes to both of these structures were observed in the sodium-iodoacetic acid-injected condyles. Structural changes detected with OCT were confirmed histologically. OCT in combination with a well-known model used in arthritis research represents a powerful tool for following degenerative joint disease progression in a given animal by detecting changes to the cartilage/bone interface and articular cartilage.  相似文献   
124.
This pilot study examined a behavioral treatment to increase calorie intake in toddlers with cystic fibrosis. Eight toddlers were randomly assigned to behavioral plus nutrition (BEH) or nutrition intervention (NTR) conditions. Calorie intake and weight were measured at pre- and posttreatment. The BEH group showed a trend for changes in calorie intake pre- to posttreatment (p = .07; 40% increase). Results for the BEH and NTR groups did not differ significantly. Most participants achieved weight gains consistent with normal growth. Seventy-five percent had not shown this pattern during the year prior to intervention. These results support the feasibility and potential for behavioral interventions in this age group.  相似文献   
125.
126.
We present a patient with tuberous sclerosis and bilateral angiomyolipomaswith a right partial staghorn calculi in which the calculi was managed with a percutaneous nephrolithotomy. Despite the inherent risk of hemorrhage with a percutaneous approach compounded by the fact that this was done directly through a tumor, we were able to render the patient stone free with no intraoperative bleeding, complications, or the need for postoperative blood transfusion. To our knowledge, this is the first reported case of percutaneous nephrolithotomy directly through a renal angiomyolipoma.  相似文献   
127.
128.
Drawing on accounts of the author's personal responses while undertaking a qualitative study on the norms governing the relationship between nurses and mothers, it is argued that such responses, rather than being seen as a source of bias, have the potential to be a source of insight and interpretation in the research. This paper tells the 'inside' story of previously published research that was 'sanitized' by the omission of any reference to die researcher's subjective responses. The recognition of such researcher responses has implications for how research is supervised and presented.  相似文献   
129.
OBJECTIVES--To determine HLA-DR4 and DR1 allele frequencies in a series of patients with newly diagnosed early inflammatory arthritis. METHODS--HLA-DR1 and DR4 frequencies were determined by oligonucleotide typing of 208 patients classified as having either rheumatoid arthritis (RA) or undifferentiated inflammatory polyarthritis. RESULTS--The frequency of occurrence of DR4 in these patients with RA did not differ significantly from that in controls in the United Kingdom (42 v 37%). HLA-DR1 was increased in the group with inflammatory polyarthritis (25 v 18%). CONCLUSIONS--The frequency of DR4 is not increased in newly diagnosed community based patients with RA. This supports the hypothesis that DR4 is less important as a marker for susceptibility to RA than it is for disease persistence or severity.  相似文献   
130.
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