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   3531篇
  免费   279篇
  国内免费   40篇
耳鼻咽喉   35篇
儿科学   85篇
妇产科学   91篇
基础医学   474篇
口腔科学   16篇
临床医学   357篇
内科学   917篇
皮肤病学   46篇
神经病学   291篇
特种医学   152篇
外科学   635篇
综合类   26篇
一般理论   4篇
预防医学   190篇
眼科学   73篇
药学   214篇
中国医学   6篇
肿瘤学   238篇
  2023年   10篇
  2022年   36篇
  2021年   68篇
  2020年   77篇
  2019年   103篇
  2018年   111篇
  2017年   55篇
  2016年   87篇
  2015年   113篇
  2014年   163篇
  2013年   179篇
  2012年   290篇
  2011年   265篇
  2010年   160篇
  2009年   135篇
  2008年   216篇
  2007年   212篇
  2006年   237篇
  2005年   204篇
  2004年   178篇
  2003年   161篇
  2002年   142篇
  2001年   37篇
  2000年   35篇
  1999年   42篇
  1998年   56篇
  1997年   38篇
  1996年   34篇
  1995年   34篇
  1994年   22篇
  1993年   23篇
  1992年   24篇
  1991年   26篇
  1990年   27篇
  1989年   27篇
  1988年   30篇
  1987年   17篇
  1986年   10篇
  1985年   10篇
  1984年   13篇
  1983年   8篇
  1981年   8篇
  1980年   8篇
  1978年   12篇
  1977年   10篇
  1976年   8篇
  1975年   8篇
  1972年   7篇
  1968年   9篇
  1963年   7篇
排序方式: 共有3850条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.
Clinical Rheumatology - IgA vasculitis (IgAV) frequently occurs during or after a mucosal infection; it also rarely occurs in patients with cancer. We hypothesized that cancer could impact the...  相似文献   
66.
Summary Neonatal hyperphenylalaninaemia caused by mutations in the gene encoding phenylalanine hydroxylase (PAH) represents a wide spectrum of metabolic phenotypes, ranging from classical phenylketonuria (PKU) to mild hyperphenylalaninaemia (MHP). The marked interindividual heterogeneity is due to the expression of multiple PAH mutations in genetic compounds. We have investigated four unusual families in which both PKU and MHP were present. In each family three different mutations in the PAH gene were identified, including two associated with PKU and one associated with MHP. The unexpected outcome of discordant phenotypes within the families described is explained by previously unrecognized parental MHP. By mutation analysis we have also predicted the phenotypical outcome in a hyperphenylalaninaemic infant born to a mother who before pregnancy had been diagnosed as having MHP. Our results demonstrate the utility of nucleic acid analysis in follow-up in PKU screening programmes.  相似文献   
67.
Constitutional thinness: unusual human phenotype of low bone quality   总被引:1,自引:0,他引:1  
CONTEXT: Low fat mass and hormonal or nutritional deficiencies are often incriminated in bone loss related to thinness. Constitutional thinness has been described in young women with low body mass index (BMI) but close-to-normal body composition, physiological menstruation, no hormonal abnormalities, and no anorexia nervosa (AN) psychological profile. OBJECTIVE: Our objective was to determine whether constitutional thinness is associated with impaired bone quality. DESIGN, SETTING, AND PARTICIPANTS: This was an observational, cross-sectional study on 25 constitutionally thin and 44 AN young women with similar low BMI (<16.5 kg/m2) and 28 age-matched controls. MAIN OUTCOME MEASURES: Femoral and lumbar spine bone mineral density by dual-energy x-ray absorptiometry, distal tibia and radius bone architecture and breaking strength by three-dimensional peripheral quantitative computed tomography, and bone turnover markers were determined. RESULTS: Constitutionally thin subjects displayed a higher percentage of fat mass than AN subjects but had similar lumbar and femoral bone mineral density, which were significantly lower than in controls (P < 0.001). Constitutionally thin subjects displayed more markedly impaired trabecular and cortical bone parameters in the distal tibia than in the radius. AN bone structure was impaired only in subjects with a long history of disease. Calculated breaking strength was decreased in constitutional thinness and long-standing AN in both the radius and the tibia. Bone markers in constitutionally thin subjects were similar to those of controls. Osteoprotegerin to receptor activator of nuclear factor kappa B ligand ratio was higher in constitutionally thin subjects than in controls or AN women. CONCLUSIONS: Young women with constitutional thinness present an unexpectedly high prevalence of low bone mass (44%) associated with small bone size, overall diminished breaking strength, but normal bone turnover. Mechanisms related to insufficient skeletal load and/or genetics are proposed to explain this new phenotype of impaired bone quality.  相似文献   
68.
69.
70.
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