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   80199篇
  免费   4380篇
  国内免费   174篇
耳鼻咽喉   968篇
儿科学   1789篇
妇产科学   1664篇
基础医学   10792篇
口腔科学   3021篇
临床医学   6250篇
内科学   19734篇
皮肤病学   1800篇
神经病学   7057篇
特种医学   1887篇
外科学   10535篇
综合类   373篇
一般理论   33篇
预防医学   7077篇
眼科学   1490篇
药学   5510篇
中国医学   297篇
肿瘤学   4476篇
  2024年   39篇
  2023年   486篇
  2022年   287篇
  2021年   1219篇
  2020年   739篇
  2019年   1312篇
  2018年   2421篇
  2017年   1559篇
  2016年   1629篇
  2015年   2189篇
  2014年   2277篇
  2013年   3246篇
  2012年   7006篇
  2011年   7204篇
  2010年   3237篇
  2009年   2360篇
  2008年   6074篇
  2007年   6272篇
  2006年   6234篇
  2005年   6009篇
  2004年   5446篇
  2003年   4968篇
  2002年   4703篇
  2001年   1617篇
  2000年   2119篇
  1999年   1064篇
  1998年   268篇
  1997年   197篇
  1996年   201篇
  1995年   186篇
  1994年   146篇
  1993年   139篇
  1992年   153篇
  1991年   137篇
  1990年   83篇
  1989年   96篇
  1988年   64篇
  1987年   59篇
  1986年   77篇
  1985年   86篇
  1984年   114篇
  1983年   74篇
  1982年   100篇
  1981年   83篇
  1980年   89篇
  1979年   48篇
  1978年   46篇
  1977年   41篇
  1976年   41篇
  1974年   44篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Context: Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action.

Objective: This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed.

Materials and methods: Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007).

Results: All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500?μg/mL for the BTHE; 156 to 1250?μg/mL for the BTCE; 625 to 1250?μg/mL for the BTME and 625?μg/mL to 2500?μg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC50 values of 981 and 3935?μg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages.

Discussion and conclusion: Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division.  相似文献   
992.
993.
Physical therapy in ankylosing spondylitis (AS) is important for maintaining or improving mobility, fitness, functioning, and global health. It also plays a role in the prevention and management of structural deformities. In this study we assessed the functional status of AS patients in relation to disease duration and activity. Furthermore, in volunteering patients we analyzed the efficacy of a controlled, individualized physiotherapeutic program. Altogether, clinical data of 75 AS patients were retrospectively analyzed. Anthropometrical data, duration since diagnosis and disease activity, pain intensity, tender points, sacroiliac joint involvement determined by X-ray, functional condition, and physical activity level were recorded. Subjective, functional, and physical tests were performed. Out of the 75 patients, 10 volunteered to undergo a complex physical exercise program twice a week for 3?months. The program included 1.5?h of general posture reeducation, manual mobilization of the spine, and pelvic-, upper-, and lower-extremity exercises, stretching with joint prevention strategies and functional exercises. In AS, pain intensity recorded on a 10-cm visual analog scale (VAS), BASFI, BASDAI, modified Schober index, chest expansion and occiput-to-wall distance values showed significant correlation with disease activity. The 3-month physical therapy improved several subjective and functional parameters, and markedly reduced pain intensity and spine stiffness. A complex, individualized physical therapy program may be useful and should be introduced to AS patients in order to maintain and increase spine mobility, preserve functional capacity, decrease the pain and stiffness.  相似文献   
994.

Aims  

The aim of this study was to compare angiogenic factors in serum levels of active ulcerative colitis (UC) patients and in healthy controls, and to analyze these angiogenic levels depending on the achievement of remission after oral corticosteroid treatment throughout treatment, and according to the Truelove–Witts activity index.  相似文献   
995.
996.
997.
998.
The objective of this study is to establish whether there is an association between the presence of FCGR3A V(176) polymorphism with SLE or its manifestations. We included 94 patients according to the 1982 ACR criteria as well as 98 controls matched by age and gender. The 11 ACR diagnostic criteria were analyzed on the clinical files. The polymorphism FCGR3A V(176) was determined by direct sequencing. There was not an association between the polymorphism FCGR3A V(176) with SLE or its main manifestations. The allelic frequency for F(176) was: 0.80 and 0.72 in cases and controls, respectively (P?=?0.09, IC95%: 0.42?C1.07); and the genotypic frequency in the group of cases was: 0.65 for homozygotes F(176)/F(176), 0.30 for heterozygotes and 0.05 for the homozygotes V(176)/V(176), while for the control group it was 0.53, 0.39 and 0.08, respectively. The polymorphism FCGR3A V(176) is not associated with SLE or any of its manifestations in patients with SLE from the West of Mexico.  相似文献   
999.
1000.
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