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   14432篇
  免费   1035篇
  国内免费   31篇
耳鼻咽喉   71篇
儿科学   583篇
妇产科学   483篇
基础医学   1762篇
口腔科学   187篇
临床医学   2265篇
内科学   2400篇
皮肤病学   212篇
神经病学   1309篇
特种医学   397篇
外国民族医学   1篇
外科学   1207篇
综合类   330篇
一般理论   25篇
预防医学   2285篇
眼科学   193篇
药学   963篇
  1篇
中国医学   23篇
肿瘤学   801篇
  2023年   149篇
  2022年   207篇
  2021年   378篇
  2020年   257篇
  2019年   404篇
  2018年   465篇
  2017年   292篇
  2016年   383篇
  2015年   409篇
  2014年   538篇
  2013年   730篇
  2012年   1175篇
  2011年   1193篇
  2010年   582篇
  2009年   537篇
  2008年   950篇
  2007年   1003篇
  2006年   939篇
  2005年   874篇
  2004年   862篇
  2003年   758篇
  2002年   671篇
  2001年   133篇
  2000年   73篇
  1999年   124篇
  1998年   174篇
  1997年   141篇
  1996年   128篇
  1995年   111篇
  1994年   108篇
  1993年   102篇
  1992年   65篇
  1991年   49篇
  1990年   41篇
  1989年   37篇
  1988年   46篇
  1987年   54篇
  1986年   55篇
  1985年   27篇
  1984年   14篇
  1983年   27篇
  1982年   37篇
  1981年   29篇
  1980年   17篇
  1979年   19篇
  1978年   10篇
  1975年   8篇
  1973年   9篇
  1968年   8篇
  1964年   8篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
Passenger leukocytes have been demonstrated to play significant roles in initiating and also regulating immune reactions after organ transplantation. Reliable techniques to detect donor leukocytes in recipients after organ transplantation are essential to analyze the role, function, and behavior of these leukocytes. In this report we describe a simple, reliable method to detect donor cells with low frequencies using peripheral blood samples. Detection of small numbers of major histocompatibility complex (MHC) mismatched cells was first studied using four-color flow cytometry in artificially created cell mixtures. By selecting the CD45(+) population and simultaneous staining with several leukocyte lineage markers (CD3, CD4, CD8, CD56, and CD19), MHC-mismatched leukocytes were consistently detected in cell suspensions prepared from directly stained whole blood samples with a threshold sensitivity as low as 0.1%-0.2%. When the fresh peripheral blood mononuclear cells were separated by conventional Ficoll gradient purification, similar, but slightly lower levels of donor cells were detected. Blood samples obtained 1-5 months after liver, kidney, and intestine transplants revealed that the kind of organ allograft influenced levels and lineage pattern of the circulating donor cells. This procedure provided a simple and reliable method in determining early chimerism in transplant recipients. However, the detection of MHC-mismatched leukocytes of all lineages was much lower when frozen peripheral blood mononuclear cells were used.  相似文献   
42.
This prospective multisite Phase III clinical trial (Miami, New York, New Jersey) investigated the long-term (one year) effects of a 10-week group cognitive-behavioral stress management/expressive supportive therapy (CBSM+) intervention on disadvantaged minority women living with AIDS. The CBSM+ intervention consisted of 10-weekly group session of stress management, cognitive-behavioral skill training, relaxation techniques and expressive-supportive therapeutic strategies. The primary study outcome was self-reported depression scores as measured by the BDI. The CBSM+ Group intervention significantly decreased depression scores on the BDI for women following the intervention and maintained the decreased level at one-year follow-up.  相似文献   
43.
Motility of unicellular organisms occurred early in evolution with the emergence of cilia and flagella. In vertebrates, motile cilia are required for numerous functions such as clearance of the airways and determination of left-right body asymmetry. Ependymal cells lining the brain ventricles also carry motile cilia, but their biological function has remained obscure. Here, we show that ependymal cilia generate a laminar flow of cerebrospinal fluid through the cerebral aqueduct, which we term as 'ependymal flow'. The axonemal dynein heavy chain gene Mdnah5 is specifically expressed in ependymal cells, and is essential for ultrastructural and functional integrity of ependymal cilia. In Mdnah5-mutant mice, lack of ependymal flow causes closure of the aqueduct and subsequent formation of triventricular hydrocephalus during early postnatal brain development. The higher incidence of aqueduct stenosis and hydrocephalus formation in patients with ciliary defects proves the relevance of this novel mechanism in humans.  相似文献   
44.
The genetic diversity of enteric viruses co-circulating in a cohort of patients with viral gastroenteritis in a large tertiary paediatric hospital in London, UK, was determined. Multiple strains of noroviruses (NV), sapoviruses (SV) and astroviruses (HAsV) were detected in these patients, indicating the likelihood of multiple introductions from different sources, possible sub-clinical infections and simultaneous infection with different viruses in immunocompromised and other patients. Routine screening of immunocompromised patients and infection control procedures are important to prevent nosocomial infection.  相似文献   
45.
Hand involvement in Schmid metaphyseal chondrodysplasia   总被引:1,自引:0,他引:1  
Schmid metaphyseal chondrodysplasia (Schmid MCD, MIM 156500) is caused by mutations in the COL10A1 gene and is clinically characterized by short stature, bowed legs, and a waddling gait. Radiographic findings include anterior cupping, sclerosis and splaying of the ribs, diffuse metaphyseal flaring, and irregularity that is most pronounced at the knees, coxa vara, and femoral bowing. We reviewed the radiographs of Schmid MCD patients at the International Skeletal Dysplasia Registry in Los Angeles for evidence of hand involvement. We found hand involvement in 47% (7/15) of cases included in our analysis. These changes were subtle and consisted of shortening of the tubular bones and metaphyseal cupping of the proximal phalanges and metacarpals. Mild hand involvement is a common feature of Schmid MCD.  相似文献   
46.
Maternal and Child Health Journal - In the US, approximately 8% of pregnant women smoke, and 5–11.9% currently use ENDS products. The health effects of ENDS use are debated; however, most...  相似文献   
47.
48.
International Urology and Nephrology - Studies based on administrative databases show that infant pyeloplasty is associated with minority race/ethnicity but lack clinical data that may influence...  相似文献   
49.
50.
Annals of Surgical Oncology - Recognizing the need to raise awareness of core diversity, equity, and inclusion (DEI) issues in the healthcare system, our previously developed Cultural Complications...  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