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   52287篇
  免费   3495篇
  国内免费   110篇
耳鼻咽喉   410篇
儿科学   1904篇
妇产科学   1871篇
基础医学   6277篇
口腔科学   611篇
临床医学   8981篇
内科学   9436篇
皮肤病学   773篇
神经病学   4753篇
特种医学   980篇
外国民族医学   33篇
外科学   4664篇
综合类   623篇
一般理论   81篇
预防医学   7142篇
眼科学   678篇
药学   2918篇
  1篇
中国医学   97篇
肿瘤学   3659篇
  2023年   319篇
  2022年   467篇
  2021年   1020篇
  2020年   692篇
  2019年   1106篇
  2018年   1262篇
  2017年   864篇
  2016年   1012篇
  2015年   1088篇
  2014年   1509篇
  2013年   2498篇
  2012年   3547篇
  2011年   3810篇
  2010年   2046篇
  2009年   1928篇
  2008年   3382篇
  2007年   3828篇
  2006年   3679篇
  2005年   3603篇
  2004年   3460篇
  2003年   3309篇
  2002年   3117篇
  2001年   413篇
  2000年   289篇
  1999年   419篇
  1998年   665篇
  1997年   536篇
  1996年   461篇
  1995年   376篇
  1994年   380篇
  1993年   369篇
  1992年   268篇
  1991年   234篇
  1990年   224篇
  1989年   177篇
  1988年   179篇
  1987年   188篇
  1986年   159篇
  1985年   186篇
  1984年   212篇
  1983年   215篇
  1982年   273篇
  1981年   250篇
  1980年   194篇
  1979年   135篇
  1978年   116篇
  1977年   135篇
  1976年   111篇
  1975年   95篇
  1973年   87篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
92.
OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs.  相似文献   
93.
Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips.  相似文献   
94.
95.
96.
97.
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors.  相似文献   
98.
The role of arthroscopy in the problem total knee replacement   总被引:2,自引:0,他引:2  
Fourteen patients were retrospectively reviewed to examine the role of arthroscopy in the diagnosis and treatment of the problem total knee arthroplasty (TKA), and to define parameters for indications, techniques, and results. All patients had undergone a previous TKA, and postoperatively had problems with pain and/or range of motion. Routine evaluation failed to reveal sepsis or aseptic loosening. Arthroscopy was used to evaluate and treat certain specific conditions. The arthroscope was successful in removing loose bodies, correcting patella subluxation with an arthroscopic lateral release, excising a symptomatic pseudomeniscus, and releasing intraarticular adhesions to improve motion and relieve pain. The postoperative knee score improved 73%. Arthroscopy is a valuable tool to evaluate a painful TKA, and can be used to treat certain conditions that would otherwise require an arthrotomy. The rehabilitation time is easier on the patient and much quicker. Arthroscopy of a TKA does not compromise any future procedures. However, it remains a technically demanding procedure whose indications and expectations are still being defined.  相似文献   
99.
100.
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