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   25799篇
  免费   1996篇
  国内免费   103篇
耳鼻咽喉   217篇
儿科学   589篇
妇产科学   429篇
基础医学   3521篇
口腔科学   328篇
临床医学   2778篇
内科学   5804篇
皮肤病学   313篇
神经病学   2337篇
特种医学   838篇
外科学   4274篇
综合类   279篇
现状与发展   1篇
一般理论   25篇
预防医学   1892篇
眼科学   408篇
药学   1801篇
中国医学   44篇
肿瘤学   2020篇
  2023年   258篇
  2022年   455篇
  2021年   1000篇
  2020年   516篇
  2019年   816篇
  2018年   927篇
  2017年   653篇
  2016年   669篇
  2015年   765篇
  2014年   1042篇
  2013年   1311篇
  2012年   2074篇
  2011年   2088篇
  2010年   1122篇
  2009年   970篇
  2008年   1610篇
  2007年   1604篇
  2006年   1462篇
  2005年   1412篇
  2004年   1345篇
  2003年   1250篇
  2002年   1229篇
  2001年   182篇
  2000年   141篇
  1999年   215篇
  1998年   250篇
  1997年   204篇
  1996年   162篇
  1995年   159篇
  1994年   160篇
  1993年   127篇
  1992年   118篇
  1991年   77篇
  1990年   107篇
  1989年   73篇
  1988年   82篇
  1987年   96篇
  1986年   83篇
  1985年   72篇
  1984年   96篇
  1983年   82篇
  1982年   92篇
  1981年   82篇
  1980年   84篇
  1979年   54篇
  1978年   57篇
  1977年   47篇
  1975年   41篇
  1973年   36篇
  1971年   35篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
14.
15.
2‐deoxy D‐glucose (2DG) was tested for efficacy in treating alopecia areata using the C3H/HeJ skin graft model. 2DG has proven to be efficacious in treatment of various mouse models of autoimmunity with minimal serious side effects noted. This agent has been shown to normalize abnormally activated T‐cell populations while also preventing cell surface expression of NKG2D; key factors defining alopecia areata disease progression. Daily oral ingestion of 2DG via drinking water to mice with patchy or diffuse alopecia areata for 16 weeks failed to prevent expansion of alopecia or cause regrowth of hair in treated mice. Histologically, there were no differences between treated and control groups. These results indicate that, while 2DG is effective for some autoimmune diseases, it was not efficacious for the cell‐mediated autoimmune mouse disease, alopecia areata.  相似文献   
16.

Background

Most elderly trauma patients suffer blunt head injury and many utilize antithrombotic (AT) medications. The utility of delayed CT-head (D-CTH) in neurologically intact elderly patients using AT who have an intracranial hemorrhage (ICH) on presentation is unknown. We hypothesized that D-CTH would not alter clinical management and aimed to evaluate the role of D-CTH in this population.

Methods

A retrospective cohort study was performed. Patients ≥65 years sustaining blunt head injuries from January 2010 to July 2017 were identified using our level 1 trauma center database. AT-patients presenting with ICH who underwent D-CTH were included. Patients with worsened ICH were compared to those with stable to improved ICH on D-CTH. AT-patients were compared to a cohort of non-AT patients. Fisher’s Exact and Mann-Whitney U tests were utilized and a power analysis conducted.

Results

137?A?T and 34 non-AT patients were identified. There was no difference in hemorrhage progression or appearance of new ICH. No patient had a change in management from D-CTH in either cohort. AT-patients were slightly older (p?<?0.001), but cohorts were otherwise similar.50 AT-patients with worsened ICH were compared to 87 with stable ICH. There was no difference in cohort demographics. Hemorrhage progression did not vary with type of AT used but did increase if multiple types of synchronous ICH were present (p?<?0.001).

Conclusions

Our data supports abstaining from routine D-CTH of elderly ICH patients with an intact neurologic examination who are utilizing aspirin, clopidogrel or warfarin. Conclusions cannot be drawn regarding new oral anticoagulants (NOACs) given low enrollment. Further multicenter study is required to provide adequate power and detect small levels of management change.  相似文献   
17.
<正>Microvascular dysfunction and rheumatoid arthritis(RA):Across the UK severe osteoarthritis affects~5–7%and RA affects~1%of the population.These are the most common causes of disabling chronic pain and are major burdens on individuals and society.Consequently,the annual financial cost to the UK economy for arthritis is in the billions of pounds.People living with painful inflammatory conditions and in  相似文献   
18.
19.
20.

Purpose

To quantify eating disorder (ED) stability and diagnostic transition among a community-based sample of adolescents and young adult females in the United States.

Methods

Using 11 prospective assessments from 9,031 U.S. females ages 9–15 years at baseline of the Growing Up Today Study, we classified cases of the following EDs involving bingeing and purging: bulimia nervosa (BN), binge ED, purging disorder (PD), and subthreshold variants defined by less frequent (monthly vs. weekly) bingeing and purging behaviors. We measured number of years symptomatic and probability of maintaining symptoms, crossing to another diagnosis, or resolving symptoms across consecutive surveys.

Results

Study lifetime disorder prevalence was 2.1% for BN and roughly 6% each for binge ED and PD. Most cases reported symptoms during only one survey year. Twenty-six percent of cases crossed between diagnoses during follow-up. Among participants meeting full threshold diagnostic criteria, transition from BN was most prevalent, crossing most frequently from BN to PD (12.9% of BN cases). Within each disorder phenotype, 20%–40% of cases moved between subthreshold and full threshold criteria across consecutive surveys.

Conclusions

Diagnostic crossover is not rare among adolescent and young adult females with an ED. Transition patterns from BN to PD add support for considering these classifications in the same diagnostic category of disorders that involve purging. The prevalence of crossover between monthly and weekly symptom frequency suggests that a continuum or staging approach may increase utility of ED classification for prognostic and therapeutic intervention.  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