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   4324篇
  免费   347篇
  国内免费   13篇
耳鼻咽喉   9篇
儿科学   221篇
妇产科学   47篇
基础医学   393篇
口腔科学   185篇
临床医学   674篇
内科学   768篇
皮肤病学   312篇
神经病学   415篇
特种医学   292篇
外科学   444篇
综合类   145篇
一般理论   3篇
预防医学   279篇
眼科学   24篇
药学   316篇
  1篇
肿瘤学   156篇
  2023年   18篇
  2022年   22篇
  2021年   53篇
  2020年   59篇
  2019年   72篇
  2018年   82篇
  2017年   80篇
  2016年   72篇
  2015年   82篇
  2014年   98篇
  2013年   136篇
  2012年   178篇
  2011年   214篇
  2010年   184篇
  2009年   138篇
  2008年   193篇
  2007年   167篇
  2006年   172篇
  2005年   154篇
  2004年   145篇
  2003年   149篇
  2002年   156篇
  2001年   128篇
  2000年   121篇
  1999年   131篇
  1998年   119篇
  1997年   114篇
  1996年   113篇
  1995年   87篇
  1994年   71篇
  1993年   69篇
  1992年   91篇
  1991年   89篇
  1990年   72篇
  1989年   98篇
  1988年   90篇
  1987年   76篇
  1986年   69篇
  1985年   83篇
  1984年   59篇
  1983年   43篇
  1982年   30篇
  1981年   27篇
  1980年   28篇
  1979年   23篇
  1978年   22篇
  1977年   25篇
  1976年   23篇
  1975年   24篇
  1973年   12篇
排序方式: 共有4684条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
Pain management in ambulatory surgery.   总被引:1,自引:0,他引:1  
Successful ambulatory surgery is dependent on analgesia that is effective, has minimal adverse effects, and can be safely managed by the patient at home after discharge. A number of studies have identified that the provision of effective postoperative analgesia is inadequate for a significant proportion of patients. The following discussion details the current available analgesic options for ambulatory surgery patients and the rationale for their use. Preemptive analgesia should be given to all patients unless there are specific contraindications. Consideration should be given to the use of long-acting oral COX-2 selective nonsteroidal anti-inflammatory drugs (NSAIDs) and long-acting oral opioids to treat postoperative pain. A standardized multimodal postdischarge analgesic regimen tailored to the patient's expected postoperative pain levels should be prescribed. Patient follow-up by telephone questionnaire will confirm those surgical procedures that result in mild or moderate-to-severe postoperative pain and the effectiveness of treatment plans.  相似文献   
6.
To assess the efficacy of intrapulmonary balloon counterpulsation in the management of right ventricular failure after right ventriculotomy, we undertook an experimental study in a swine model. To mimic the clinical settings more closely, (1) we left the automatic control of the heart intact (2) did not use cardiopulmonary bypass to support the left side of the heart, and (3) induced right ventricular failure by means of a generous surgical incision (50% to 70% of the anterior wall) of the right ventricle. The criteria set for right ventricular failure were (1) 50% increase in right ventricular end-diastolic pressure, (2) 30% decrease in mean arterial pressure, and (3) 30% decrease in cardiac output. Right ventricular failure was attained in all animals studied: A 230% increase in right ventricular end-diastolic pressure, a 43% decrease in cardiac output, and a 34% decrease in mean arterial pressure were evident after the right ventriculotomy. A specially designed intrapulmonary balloon catheter (Datascope Corp., Oakland, N.J.) was placed into the left pulmonary artery through the right ventricular outflow tract. A Datascope console was used for counterpulsation. Effects of counterpulsation for 40 minutes in a 1:1 mode were assessed after surgical induction of right ventricular failure in 14 swine. Each animal served as its own control. The mean hemodynamic changes are outlined: Right ventricular end-diastolic pressure decreased by 48.9% (p = 0.01). Mean arterial pressure increased by 68.8% (p = 0.01) and cardiac output by 44.2% (p = 0.01). Histologic studies disclosed no morphologic damage to the pulmonary artery or valve in the specimens analyzed. In addition, these results were compared with those in a second group of seven swine in which right ventricular failure was induced by right ventriculotomy and a balloon was placed into the left pulmonary artery but not activated. These results of short-term counterpulsation should be evaluated in a longer term model so as to mimic more closely the clinical setting. If the hemodynamic benefits are duplicated, intrapulmonary balloon counterpulsation should be considered as a simple, effective device when right ventricular failure develops after right ventriculotomy. It effectively improves right ventricular function without damaging the pulmonary artery or valve.  相似文献   
7.
Peptide growth factors and wound healing   总被引:10,自引:0,他引:10  
An analysis of peptide growth factors and wound healing should not fail to give credit to its foundations in cancer research. Add the recent advances in peptide chemistry and molecular genetics that have permitted complete definitions and in vivo studies for the first time. The result is an enormous break-through in wound healing research. The potential for understanding and then using the growth factors to enhance healing in the aged or debilitated is incalculable.  相似文献   
8.
Following major quantitative expansions of the educational system in Swaziland during the two decades since independence, the focus has shifted to improving efficiency. Efficiency of any educational system depends mainly on the characteristics of children entering school. Although Swaziland is not among the poorest countries, infant child mortality rates still reflect less than optimum living conditions and parental knowledge of child nutrition and disease prevention and management. Although access to primary schooling is universal, there is substantial waste during the early years of school through dropout and repetition, both associated with low socioeconomic status. School performance can be increased at little extra cost through increasing the nutrition and health status of students before school entry and through the early school years. In Swaziland, many activities are carried out to provide physical and mental health care to students. Coordinating these efforts and formulating clear policy on school health through cooperation among key ministries and nongovernmental organizations remains to be done.  相似文献   
9.
1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process.  相似文献   
10.

Background  

The aims of this study were to examine the extent to which higher intellectual abilities protect higher socio-economic groups from functional decline and to examine whether the contribution of intellectual abilities is independent of childhood deprivation and low birth weight and other socio-economic and developmental factors in early life.  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