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   7892篇
  免费   710篇
  国内免费   25篇
耳鼻咽喉   82篇
儿科学   279篇
妇产科学   328篇
基础医学   1176篇
口腔科学   156篇
临床医学   707篇
内科学   1667篇
皮肤病学   272篇
神经病学   779篇
特种医学   184篇
外国民族医学   1篇
外科学   1209篇
综合类   52篇
一般理论   5篇
预防医学   658篇
眼科学   170篇
药学   426篇
中国医学   15篇
肿瘤学   461篇
  2023年   56篇
  2022年   27篇
  2021年   234篇
  2020年   124篇
  2019年   248篇
  2018年   260篇
  2017年   183篇
  2016年   196篇
  2015年   244篇
  2014年   297篇
  2013年   343篇
  2012年   511篇
  2011年   516篇
  2010年   293篇
  2009年   280篇
  2008年   430篇
  2007年   420篇
  2006年   394篇
  2005年   349篇
  2004年   315篇
  2003年   288篇
  2002年   256篇
  2001年   223篇
  2000年   239篇
  1999年   209篇
  1998年   69篇
  1997年   70篇
  1996年   57篇
  1995年   52篇
  1994年   47篇
  1993年   37篇
  1992年   127篇
  1991年   123篇
  1990年   110篇
  1989年   105篇
  1988年   123篇
  1987年   90篇
  1986年   97篇
  1985年   67篇
  1984年   56篇
  1983年   40篇
  1982年   31篇
  1981年   29篇
  1980年   27篇
  1979年   37篇
  1978年   26篇
  1977年   28篇
  1976年   35篇
  1974年   40篇
  1973年   26篇
排序方式: 共有8627条查询结果,搜索用时 823 毫秒
1.
2.
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.  相似文献   
3.
4.
Introduction and objectivesBiological aerosols play a vital role in the interactions between the atmosphere, biosphere, climate and public health and fungal spores are a component with allergic importance.We constructed a database in Castile & Leon (Spain) and carry out molecular-level component-resolved diagnosis to complete the air quality study carried out since 2006 by our aerobiological network (RACYL) to aid clinical diagnosis and treatment.MethodsWe reviewed a database of 19,774 patients (adults and children) with allergic respiratory disease treated in our unit during the last 12 years. We also made a component-resolved diagnosis of the molecules involved in the pathology in a randomly selected population of 150 patients.ResultsThe dimeric glycoprotein Alt a1 from Alternaria is the most prevalent and most useful allergen in the diagnosis of patients with allergy to fungi in our area (94.4%), followed by enolase Alt a 6 (Alternaria), ribonuclease Asp f 1 of Aspergillus and mannitol dehydrogenase from Cla h 8 (Cladosporium).ConclusionsOur results have helped determine which spore molecules are most-closely associated with allergies. Molecular analysis will be useful to determine more accurate and useful immunotherapy in these patients.  相似文献   
5.
6.
Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor.  相似文献   
7.
Oral allergy syndrome induced by spinach   总被引:1,自引:1,他引:0  
  相似文献   
8.
We report a case of vasoactive-agent-induced priapism successfully treated in the emergency department with 10 mg of metaraminol injected into the corpora cavernosa.  相似文献   
9.
10.
Research on physical activity (PA) by level of acculturation in Hispanic children is limited and findings have been mixed. We examined PA participation by primary language used with parents in a representative sample of 4th, 8th, and 11th grade Texas public school students. Mixed-effects regression models were conducted using cross-sectional data from the 2004–2005 School Physical Activity and Nutrition Study (n = 22,049). Self-reported PA was compared among three language-ethnic groups: Spanish-Hispanic (SH) (referent); English-Hispanic (EH); and English-Other (EO). EH and/or EO girls were generally between 1.25 and 2.58 [OR] times more likely to participate in PA across grade levels, with the largest differences found for school sports in 8th grade girls. EH and EO 8th grade boys were 1.71 (CI: 1.40, 2.10) and 2.06 (CI: 1.68, 2.51) times, respectively, more likely to participate in school sports. Findings indicate important disparities in Spanish-speaking Hispanic children’s PA participation.  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