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   28506篇
  免费   2582篇
  国内免费   52篇
耳鼻咽喉   255篇
儿科学   1021篇
妇产科学   717篇
基础医学   3958篇
口腔科学   413篇
临床医学   3274篇
内科学   5570篇
皮肤病学   378篇
神经病学   2449篇
特种医学   859篇
外国民族医学   5篇
外科学   3695篇
综合类   534篇
一般理论   22篇
预防医学   2921篇
眼科学   884篇
药学   2284篇
中国医学   36篇
肿瘤学   1865篇
  2022年   167篇
  2021年   494篇
  2020年   310篇
  2019年   484篇
  2018年   555篇
  2017年   465篇
  2016年   486篇
  2015年   563篇
  2014年   735篇
  2013年   1113篇
  2012年   1636篇
  2011年   1730篇
  2010年   970篇
  2009年   821篇
  2008年   1396篇
  2007年   1527篇
  2006年   1398篇
  2005年   1446篇
  2004年   1359篇
  2003年   1316篇
  2002年   1163篇
  2001年   680篇
  2000年   678篇
  1999年   585篇
  1998年   351篇
  1997年   282篇
  1996年   226篇
  1995年   257篇
  1994年   249篇
  1993年   214篇
  1992年   502篇
  1991年   482篇
  1990年   473篇
  1989年   427篇
  1988年   441篇
  1987年   403篇
  1986年   370篇
  1985年   350篇
  1984年   312篇
  1983年   264篇
  1982年   192篇
  1981年   168篇
  1979年   271篇
  1978年   215篇
  1977年   175篇
  1976年   175篇
  1975年   168篇
  1974年   177篇
  1973年   204篇
  1972年   171篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   
3.
4.
INTRODUCTIONPsoriasis is a chronic inflammatory condition that affects the skin and joints, and is associated with cardiovascular risk factors, including metabolic syndrome (MetS). We aimed to assess the prevalence of MetS in patients with psoriasis and determine whether there was a correlation between psoriasis severity and MetS in a Singapore population.METHODSThis was a cross-sectional study of patients with psoriasis, aged 18–69 years, who attended a tertiary dermatology referral centre in Singapore from October 2007 to February 2009. Fasting glucose, lipids, blood pressure, Psoriasis Area and Severity Index, and body mass index were measured. MetS was diagnosed in the presence of three or more criteria of the modified National Cholesterol Education Program Adult Treatment Panel III.RESULTSAmong 338 patients with psoriasis, there were 238 (70.4%) men and 100 (29.6%) women, who were Chinese (n = 228; 67.5%), Malay (n = 52; 15.4%) and Indian (n = 58; 17.2%). The prevalence of MetS was 45.1%. MetS was 44% more prevalent in patients older than 50 years (p = 0.02). Malay patients with psoriasis were significantly more likely to have hypertriglyceridaemia, elevated fasting plasma glucose and abdominal obesity. There was no significant correlation between psoriasis severity and risk of MetS.CONCLUSIONThe prevalence of MetS in patients with psoriasis in Singapore was 45.1%, or nearly threefold higher than the Singapore general population. Patients with psoriasis should be screened yearly for MetS and any modifiable cardiovascular risk factors should be actively controlled.  相似文献   
5.
6.
7.
8.
9.
PurposeRegional nodal irradiation (RNI) improved disease-free survival by 3% to 5% in 2 large randomized trials, but this small absolute advantage relies on accurate contouring and dose delivery. We audited our network to determine compliance on regional nodal coverage, contouring, and dosimetric parameters with respect to accepted guidelines.Methods and MaterialsIn our network, we have established a clinical pathway for patients with node-positive breast cancer that guides indications for RNI and dosimetric goals. We reviewed records of 183 patients with nodal macrometastases after upfront surgery or involved nodes of any size after neoadjuvant chemotherapy. Radiation treatment plans were examined to determine lymph node volumes treated, whether nodes were contoured, quality of nodal contours, and whether target coverage and normal organ dosimetric constraints were met when RNI was delivered.ResultsDespite the presence of macrometastases on sentinel lymph node biopsy, no lymph nodes were treated in 2.2% (4 of 183). Of 179 patients who received nodal irradiation, 18 received radiation to axillary levels 1 and 2 only, and 161 patients received RNI. Overall, regional nodes were not treated despite strong indications in 7.6% (14 of 183). Treated nodes were not contoured for 2.2% (4 of 179), and lymph node contours were unacceptable in 15.4% (27 of 175). Of patients receiving RNI, 14.9% (24 of 161) did not have adequate nodal target volume coverage, mean heart dose was >4 Gy for 3.1% (5 of 161), and lung V20 Gy was >35% for 8.7% (14 of 161).ConclusionsAdherence to indications for regional nodal treatment was high, but nodes were either not contoured or had unacceptable contour quality in 18% of plans, and coverage was inadequate in 15%. Because the small disease-free survival advantage seen in trials may be decreased with these deviations, routine clinical practice requires detailed peer review to fully translate results of clinical trials.  相似文献   
10.
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