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   14555篇
  免费   1161篇
  国内免费   36篇
耳鼻咽喉   101篇
儿科学   498篇
妇产科学   316篇
基础医学   2055篇
口腔科学   107篇
临床医学   1988篇
内科学   2937篇
皮肤病学   226篇
神经病学   1457篇
特种医学   344篇
外科学   1451篇
综合类   157篇
一般理论   21篇
预防医学   1801篇
眼科学   166篇
药学   1038篇
中国医学   16篇
肿瘤学   1073篇
  2024年   29篇
  2023年   240篇
  2022年   290篇
  2021年   589篇
  2020年   382篇
  2019年   645篇
  2018年   636篇
  2017年   420篇
  2016年   468篇
  2015年   467篇
  2014年   581篇
  2013年   843篇
  2012年   1260篇
  2011年   1251篇
  2010年   598篇
  2009年   556篇
  2008年   862篇
  2007年   893篇
  2006年   877篇
  2005年   795篇
  2004年   654篇
  2003年   635篇
  2002年   591篇
  2001年   88篇
  2000年   70篇
  1999年   88篇
  1998年   102篇
  1997年   106篇
  1996年   73篇
  1995年   76篇
  1994年   42篇
  1993年   53篇
  1992年   45篇
  1991年   37篇
  1990年   31篇
  1989年   30篇
  1988年   27篇
  1987年   23篇
  1986年   17篇
  1985年   12篇
  1984年   21篇
  1983年   24篇
  1982年   21篇
  1981年   30篇
  1980年   16篇
  1979年   17篇
  1978年   15篇
  1977年   30篇
  1976年   21篇
  1971年   10篇
排序方式: 共有10000条查询结果,搜索用时 23 毫秒
61.
62.
BackgroundMaintenance of patellar stability requires a balance between the vastus medialis oblique (VMO) and the vastus lateralis (VL). The imbalance between these muscles is thought to be implicated in the etiology of patellofemoral pain (PFP). Where there is hypertrophy of the VL in PFP patients, self-myofascial release (SMR) may be utilized for its management. However, there is no current evidence regarding SMR and its effects on VMO and VL architecture. The aim of this study, therefore, was to use ultrasound to gain further understanding of the effects of a program of SMR on the fiber angles of the VMO and VL.HypothesisThere will be a significant decrease in the pennation angles of the VMO and VL after seven weeks of SMR using a foam roller.Study DesignCohort StudyMethodsTwenty-five young, athletic, male participants were recruited to use a foam roller, along the full length of both anterior thighs, three times weekly, on three separate days, for seven weeks. Ultrasound was used to determine the initial and final VMO and VL pennation angles on both limbs. One eligible participant was chosen as an intra-rater control and did not partake in the SMR regimen.ResultsThere was a statistically significant (p < 0.001) decrease in the pennation angles of the VMO and VL after the SMR regime. Mean combined right and left VL angle change was -6.65° (-18% mean change) and the mean combined right and left VMO angle change was -7.65° (-11.5% mean change). A weak negative correlation was found between initial VMO fiber angle and the angle change (Rsquared = -0.21), as well as moderate negative correlation for the VL (Rsquared = -0.51).ConclusionA program of SMR on the anterior thighs of young, asymptomatic males resulted in changes to the fiber angles of both the VMO and VL. There was a significant decrease in pennation angle after seven weeks of SMR using a foam roller.  相似文献   
63.
64.
Background Whole-genome sequencing (WGS) of cancers is becoming an accepted component of oncological care, and NHS England is currently rolling out WGS for all children with cancer. This approach was piloted during the 100,000 genomes (100 K) project. Here we share the experience of the East of England Genomic Medicine Centre (East-GMC), reporting the feasibility and clinical utility of centralised WGS for individual children locally.Methods Non-consecutive children with solid tumours were recruited into the pilot 100 K project at our Genomic Medicine Centre. Variant catalogues were returned for local scrutiny and appraisal at dedicated genomic tumour advisory boards with an emphasis on a detailed exploration of potential clinical value.Results Thirty-six children, representing one-sixth of the national 100 K cohort, were recruited through our Genomic Medicine Centre. The diagnoses encompassed 23 different solid tumour types and WGS provided clinical utility, beyond standard-of-care assays, by refining (2/36) or changing (4/36) diagnoses, providing prognostic information (8/36), defining pathogenic germline mutations (1/36) or revealing novel therapeutic opportunities (8/36).Conclusion Our findings demonstrate the feasibility and clinical value of centralised WGS for children with cancer. WGS offered additional clinical value, especially in diagnostic terms. However, our experience highlights the need for local expertise in scrutinising and clinically interpreting centrally derived variant calls for individual children.Subject terms: Cancer genomics, Cancer genomics  相似文献   
65.
66.
67.
The brown alga Cystoseira baccata harvested along the Atlantic coasts of Morocco yielded seven new meroditerpenoids (1-4) and derivatives (5-7), whose chemical structures were elucidated mainly by 2D NMR and mass spectrometry. Surprisingly, for all these compounds, which possess a bicyclo[4.3.0]nonane ring system, a trans fusion of the bicyclic system was deduced by stereochemical studies even though such compounds isolated from Cystoseira species are known to have a typical cis orientation for the bridgehead methyls. The antifouling and antibacterial activities of compounds 1-5 and 7 were evaluated, as well as their toxicity toward nontarget species. Compounds 4, 5, and 7 showed antifouling activities against growth of microalgae, macroalgal settlement, and mussel phenoloxidase activity, while being nontoxic to larvae of sea urchins and oysters.  相似文献   
68.
69.
Oocyte donors are chosen among phenotypically normal and fertile women who are not expected to carry any chromosomal abnormality. A high incidence of balanced structural chromosomal rearrangements has been found within oocyte donors. This result raises the question of a possible bias in their recruitment with respect to their familial background and/or personal reproductive history.  相似文献   
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