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   7713篇
  免费   442篇
  国内免费   44篇
耳鼻咽喉   138篇
儿科学   173篇
妇产科学   120篇
基础医学   923篇
口腔科学   219篇
临床医学   757篇
内科学   1618篇
皮肤病学   108篇
神经病学   950篇
特种医学   257篇
外科学   1330篇
综合类   83篇
一般理论   1篇
预防医学   410篇
眼科学   76篇
药学   424篇
中国医学   12篇
肿瘤学   600篇
  2023年   61篇
  2022年   122篇
  2021年   194篇
  2020年   126篇
  2019年   153篇
  2018年   176篇
  2017年   125篇
  2016年   185篇
  2015年   170篇
  2014年   243篇
  2013年   312篇
  2012年   492篇
  2011年   498篇
  2010年   270篇
  2009年   251篇
  2008年   398篇
  2007年   378篇
  2006年   394篇
  2005年   360篇
  2004年   361篇
  2003年   348篇
  2002年   290篇
  2001年   206篇
  2000年   188篇
  1999年   178篇
  1998年   72篇
  1997年   76篇
  1996年   63篇
  1995年   52篇
  1994年   51篇
  1993年   49篇
  1992年   103篇
  1991年   88篇
  1990年   82篇
  1989年   84篇
  1988年   65篇
  1987年   67篇
  1986年   77篇
  1985年   61篇
  1984年   47篇
  1983年   45篇
  1982年   36篇
  1981年   40篇
  1978年   36篇
  1977年   36篇
  1976年   42篇
  1975年   51篇
  1974年   40篇
  1973年   40篇
  1972年   35篇
排序方式: 共有8199条查询结果,搜索用时 15 毫秒
61.
62.
A group of six subjects was trained, using biofeedback procedures, in the voluntary regulation of hand temperature as a means of controlling migraine attacks. The training procedure and its relationship to migraine activity is described. Daily records of migraine activity were kept during base-line, training, and follow-up periods. Analysis of this data revealed statistically and clinically significant improvement on several indices of migraine activity. Evidence for a concomitant improvement in the ability of subjects to produce voluntary increases in hand temperature is presented.  相似文献   
63.
64.
65.
In this study, unemployed blue-collar workers over the age of 45 (N = 51) filled out a questionnaire in 1975 and in 1977. It was shown that prolonged unemployment or re-unemployment leads to depression, reduced hope, and financial problems, although none of these factors leads to prolonged unemployment. Being employed or retired leads to a reduction of depression and financial problems. Problems associated with the daily hassles of unemployment, such as financial problems and disappointed hope play a role in the development of depression with prolonged unemployment. Potential third variables that could cause both unemployment and depression--such as internal/external control, passivity, sickness, and age--do not affect the effect of unemployment on depression.  相似文献   
66.
Objective: Whether dietary carbohydrate (CHO) or fat is more involved in type 2 diabetes (T2DM) induction uncomplicated by dietary fiber was addressed in a spontaneous diabetic model, the diurnal Nile rat that mimics the human condition. Methods: A total of 138 male Nile rats were fed plant-based and animal-based saturated fat where 10% energy as CHO and fat were exchanged across 5 diets keeping protein constant, from 70:10:20 to 20:60:20 as CHO:fat:protein %energy. Diabetes induction was analyzed by: 1. diet composition, i.e., CHO:fat ratio, to study the impact of diet; 2. quintiles of average caloric intake per day to study the impact of calories; 3. quintiles of diabetes severity to study the epigenetic impact on diabetes resistance. Results: High glycemic load (GLoad) was most problematic if coupled with high caloric consumption. Diabetes severity highlighted rapid growth and caloric intake as likely epigenetic factors distorting glucose metabolism. The largest weanling rats ate more, grew faster, and developed more diabetes when the dietary GLoad exceeded their gene-based metabolic capacity for glucose disposal. Diabetes risk increased for susceptible rats when energy intake exceeded 26 kcal/day and the GLoad was >175/2000 kcal of diet and when the diet provided >57% energy as CHO. Most resistant rats ate <25 kcal/day independent of the CHO:fat diet ratio or the GLoad adjusted to body size. Conclusion: Beyond the CHO:fat ratio and GLoad, neither the type of fat nor the dietary polyunsaturated/saturated fatty acid (P/S) ratio had a significant impact, suggesting genetic permissiveness affecting caloric and glucose intake and glucose disposition were key to modulating Nile rat diabetes. Fat became protective by limiting GLoad when it contributed >40% energy and displaced CHO to <50% energy, thereby decreasing the number of diabetic rats and diabetes severity.  相似文献   
67.
Liposarcomas account for approximately 20% of all adult sarcomas and have limited therapeutic options outside of surgery. Inhibition of ataxia-telangiectasia and Rad3 related protein kinase (ATR) has emerged as a promising chemotherapeutic strategy in various cancers. However, its activation, expression, and function in liposarcoma remain unkown. In this study, we investigated the expression, function, and potential of ATR as a therapeutic target in liposarcoma. Activation and expression of ATR in liposarcoma was analyzed by immunohistochemistry, which was further explored for correlation with patient clinical characteristics. ATR-specific siRNA and the ATR inhibitor VE-822 were applied to determine the effect of ATR inhibition on liposarcoma cell proliferation and anti-apoptotic activity. Migration activity and clonogenicity were examined using wound healing and clonogenic assays. ATR (p-ATR) was overexpressed in 88.1% of the liposarcoma specimens and correlated with shorter overall survival in patients. Knockdown of ATR via specific siRNA or inhibition with VE-822 suppressed liposarcoma cell growth, proliferation, migration, colony-forming ability, and spheroid growth. Importantly, ATR inhibition significantly and synergistically enhanced liposarcoma cell line chemosensitivity to doxorubicin. Our findings support ATR as critical to liposarcoma proliferation and doxorubicin resistance. Therefore, the addition of ATR inhibition to a standard doxorubicin regimen is a potential treatment strategy for liposarcoma.  相似文献   
68.
69.
INTRODUCTION: Intentional or unintentional placement of a pacemaker lead into the left ventricle is an uncommon clinical entity that is associated with a high risk for systemic embolization and enormous difficulties in case of explantation. Unintentional implantation through a patent foramen ovale via the mitral valve is the usual pathway for this malposition. METHODS: We report a case where a pacemaker lead was placed intentionally into the left ventricle via a patent foramen ovale for biventricular pacing for resynchronization therapy. Later, the patient developed life-threatening pacemaker lead-associated endocarditis with sepsis. Emergency open heart surgery for lead removal was necessary in the form of a reoperation after bypass graft surgery a number of years earlier. CONCLUSION: Although it is technically feasible to implant the pacemaker lead into the left ventricle via a patent foramen ovale, we consider this option to be obsolete for use with a biventricular pacemaker, due to the multitude of risks, which can, in part, be life-threatening for the patient.  相似文献   
70.
We evaluated treatment with linezolid, dosed at 800 mg once daily for 1 to 4 months as guided by sputum culture status and tolerance and then at 1,200 mg thrice weekly until ≥1 year after culture conversion, in addition to individually optimized regimens among 10 consecutive patients with extensively drug-resistant tuberculosis or fluoroquinolone-resistant multidrug-resistant tuberculosis. All achieved stable cure, with anemia corrected and neuropathy stabilized, ameliorated, or avoided after switching to intermittent dosing. Serum linezolid profiles appeared better optimized.  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