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   25868篇
  免费   1356篇
  国内免费   171篇
耳鼻咽喉   288篇
儿科学   492篇
妇产科学   304篇
基础医学   2987篇
口腔科学   589篇
临床医学   1712篇
内科学   6923篇
皮肤病学   477篇
神经病学   2094篇
特种医学   1004篇
外科学   4952篇
综合类   61篇
预防医学   709篇
眼科学   475篇
药学   1423篇
中国医学   63篇
肿瘤学   2842篇
  2023年   189篇
  2022年   336篇
  2021年   752篇
  2020年   411篇
  2019年   529篇
  2018年   699篇
  2017年   482篇
  2016年   646篇
  2015年   625篇
  2014年   865篇
  2013年   998篇
  2012年   1590篇
  2011年   1867篇
  2010年   1045篇
  2009年   925篇
  2008年   1555篇
  2007年   1632篇
  2006年   1569篇
  2005年   1640篇
  2004年   1650篇
  2003年   1494篇
  2002年   1415篇
  2001年   385篇
  2000年   382篇
  1999年   374篇
  1998年   292篇
  1997年   281篇
  1996年   209篇
  1995年   182篇
  1994年   184篇
  1993年   151篇
  1992年   240篇
  1991年   227篇
  1990年   209篇
  1989年   175篇
  1988年   152篇
  1987年   137篇
  1986年   136篇
  1985年   102篇
  1984年   73篇
  1983年   67篇
  1982年   49篇
  1981年   37篇
  1980年   35篇
  1979年   58篇
  1978年   29篇
  1977年   35篇
  1975年   30篇
  1974年   28篇
  1970年   28篇
排序方式: 共有10000条查询结果,搜索用时 484 毫秒
1.
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
2.
Background: Gait disorders are common in Parkinson’s disease patients who respond poorly to dopaminergic treatment. Blockade of adenosine A2A receptors is expected to improve gait disorders. Istradefylline is a first-in-class selective adenosine A2A receptor antagonist with benefits for motor complications associated with Parkinson’s disease.

Research design and methods: This multicenter, open-label, single-group, prospective interventional study evaluated changes in total gait-related scores of the Part II/III Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) and Freezing of Gait Questionnaire (FOG-Q) in 31 Parkinson’s disease patients treated with istradefylline. Gait analysis by portable gait rhythmogram was performed.

Results: MDS-UPDRS Part III gait-related total scores significantly decreased at Weeks 4–12 from baseline with significant improvements in gait, freezing of gait, and postural stability. Significant decreases in MDS-UPDRS Part II total scores and individual item scores at Week 12 indicated improved daily living activities. At Week 12, there were significant improvements in FOG-Q, new FOG-Q, and overall movement per 48 h measured by portable gait rhythmogram. Adverse events occurred in 7/31 patients.

Conclusions: Istradefylline improved gait disorders in Parkinson’s disease patients complicated with freezing of gait, improving their quality of life. No unexpected adverse drug reactions were identified.

Trial registration: UMIN-CTR (UMIN000020288).  相似文献   

3.
4.
Daily exposure to sunlight is known to affect the structure and function of the epidermal basement membrane (BM), as well as epidermal differentiation and epidermal barrier function. The aim of this study is to clarify whether the inhibition of BM‐degrading enzymes such as heparanase and matrix metalloproteinase 9 (MMP‐9) can improve the epidermal barrier function of facial skin, which is exposed to the sun on a daily basis. 1‐(2‐hydroxyethyl)‐2‐imidazolidinone (HEI) was synthesized as an inhibitor of both heparanase and MMP‐9. HEI inhibited not only the BM damage at the DEJ but also epidermal proliferation, differentiation, water contents and transepidermal water loss abnormalities resulting from ultraviolet B (UVB). This was determined in this study by the use of UVB‐induced human cultured skins as compared with the control without HEI. Moreover, topical application of HEI improved epidermal barrier function by increasing water content and decreasing transepidermal water loss in daily sun‐exposed facial skin as compared with non‐treated skins. These results suggest that the inhibition of both heparanase and MMP‐9 is an effective way to care for regularly sun‐exposed facial skin by protecting the BM from damage.  相似文献   
5.
<正>Stroke is a leading cause of mortality and severe neurological disability worldwide; however, curative therapeutic options are limited. Although recanalization therapy using endovascular thrombectomy has demonstrated great benefits in the functional outcome of patients with acute ischemic stroke, the rate of excellent clinical outcomes remains limited. Therefore, the current recanalization  相似文献   
6.
Congenital rubella syndrome (CRS) results from maternal rubella virus infection in early pregnancy. Abnormal neuroimaging findings have been analyzed in a small number of CRS patients in the past; however, their clinical significance has been poorly addressed. Therefore, we have investigated the neuroimaging findings of 31 patients with CRS from previous studies. The most common finding was parenchymal calcification, which was observed in 18 of 31 patients (58.1%). A multivariable logistic regression model showed that it was associated with psychomotor or mental retardation (p = 0.018), suggesting that parenchymal calcification in CRS could be a prognostic factor.  相似文献   
7.
miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.  相似文献   
8.
9.
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