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   7477篇
  免费   223篇
  国内免费   7篇
耳鼻咽喉   275篇
儿科学   264篇
妇产科学   369篇
基础医学   448篇
口腔科学   116篇
临床医学   441篇
内科学   1608篇
皮肤病学   313篇
神经病学   340篇
特种医学   519篇
外科学   2021篇
综合类   33篇
预防医学   311篇
眼科学   271篇
药学   69篇
中国医学   1篇
肿瘤学   308篇
  2023年   13篇
  2021年   15篇
  2020年   13篇
  2018年   34篇
  2017年   22篇
  2016年   34篇
  2015年   514篇
  2014年   576篇
  2013年   588篇
  2012年   590篇
  2011年   551篇
  2010年   606篇
  2009年   562篇
  2008年   600篇
  2007年   528篇
  2006年   504篇
  2005年   437篇
  2004年   284篇
  2003年   91篇
  2002年   51篇
  2001年   42篇
  2000年   39篇
  1999年   64篇
  1998年   41篇
  1997年   59篇
  1996年   55篇
  1995年   37篇
  1994年   31篇
  1993年   40篇
  1992年   35篇
  1991年   42篇
  1990年   27篇
  1989年   34篇
  1988年   36篇
  1987年   45篇
  1986年   29篇
  1985年   27篇
  1984年   29篇
  1983年   38篇
  1982年   40篇
  1981年   39篇
  1980年   33篇
  1979年   31篇
  1978年   14篇
  1977年   18篇
  1976年   19篇
  1975年   18篇
  1974年   14篇
  1973年   14篇
  1972年   14篇
排序方式: 共有7707条查询结果,搜索用时 0 毫秒
991.
992.
Oral contraceptives are usually taken for 21 days followed by a 7 day pill-free interval. This interval results in a monthly bleeding pattern that is perceived as natural but which is not physiologically necessary and in some women is even associated with considerable discomfort. The present paper explains the theoretical background of the extended cycle regimen (i.e. the continuous intake over a longer period of time) and reviews the practical experience available to date.  相似文献   
993.
994.
995.
Permanent reduction of morbidity and death in centers for pancreatic surgery has led to a change in the indication for total pancreatectomy from rescue pancreatectomy for complications of pancreatic surgery increasingly to elective surgery, especially in the management of advanced intraductal papillary mucinous neoplasms. We discuss the indication for oncologic total pancreatectomy, rescue pancreatectomy, and removal of the whole pancreas for chronic pancreatitis. Furthermore we describe technical and metabolic aspects following total pancreatectomy.  相似文献   
996.
997.
The main target of treatment in patients with head trauma is to maintain the physiological parameters within the following normal limits: intracranial pressure (ICP) below 20 mmHg, cerebral perfusion pressure (CPP) between 50 and 70 mmHg, normoxemia (SpO2 >90%), normocapnia (paCO2: 35–38 mmHg), normoglycemia (80–130 mg/dl) and normothermia (36.0–37.5°C). Space-occupying intracranial bleeding or edemas must be evacuated immediately. If these interventions do not result in adequate control of ICP and CPP, the next step would be to administer mannitol and barbiturates. Mild hyperventilation, therapeutic hypothermia, or decompressive craniectomy should be used solely in patients with a persistent ICP increase. Infusion of calcium antagonists or glucocorticoids is never indicated in patients with head trauma.  相似文献   
998.
999.
Regular physical activity is key to avoiding or delaying age-related health problems and minimising their impact. In Western societies, the old and older population (the 75+ population segment in particular) is the least likely to exercise or do the recommended amount of health-enhancing physical activity. Thus far, there has been insufficient understanding of and research on the prevalence, impact and effectiveness of the wide array of physical activities that the old and older population can do to improve their health and degree of independence. Along this line, non-sports-related activities should receive special attention. Due to the limited extent of knowledge, there are few age-specific recommendations for physical activity. Subsequent research should focus more on the problems and realities of physical activity in the older and old population. This may serve to clarify and consolidate a scientific and practical consensus leading up to age-specific guidelines for physical activity.  相似文献   
1000.
Intraoperative Radiotherapy of Soft Tissue Sarcoma of the Extremity   总被引:2,自引:0,他引:2  
PURPOSE: Evaluation of treatment outcome after intraoperative radiotherapy (IORT) +/- external-beam irradiation (EBRT) in patients with localized soft tissue sarcoma of the extremity at high risk for local recurrence after limb-sparing surgery. PATIENTS AND METHODS: 28 patients treated between 1989 and 1999 were evaluated retrospectively. Patients presented with locally recurrent (n = 17), T2 (n = 20), high-grade (n = 26), or incompletely resected tumors (n = 11). All patients underwent limbsparing surgery and IORT (median dose of 15 Gy) given either with high-dose-rate brachytherapy or a linear accelerator. 25 patients received additional EBRT with a mean of 50.6 Gy (range: 30.6-60 Gy). The mean follow-up time was 4.3 years (95% confidence interval [CI]: 3.0-5.6 years). RESULTS: The 5-year overall and distant disease-free survival rates were 66% and 54%, respectively. The overall actuarial recurrence rate after 5 years is 16% (95% CI: 1%, 31%). The crude rate after 8 years is 18%. Surgical margin status, primary versus recurrent tumor and tumor stage did not show any statistically significant influence (univariate analysis) on local recurrence rates. Patients with T1 tumors exhibited a borderline significant (p = 0.053) better distant disease-free survival (83%) compared to T2 tumors (43%). Five (24%) grade 3-4 late side effects were observed. CONCLUSION: In patients with high-risk soft tissue sarcomas, IORT +/- EBRT after limb-preserving surgery achieves high local control rates. The risk of normal tissue toxicities is comparable to conventional limb-sparing treatment.  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