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   12100篇
  免费   731篇
  国内免费   29篇
耳鼻咽喉   102篇
儿科学   269篇
妇产科学   229篇
基础医学   1594篇
口腔科学   256篇
临床医学   1552篇
内科学   2235篇
皮肤病学   76篇
神经病学   1105篇
特种医学   386篇
外科学   1605篇
综合类   134篇
一般理论   12篇
预防医学   1399篇
眼科学   222篇
药学   961篇
中国医学   14篇
肿瘤学   709篇
  2023年   81篇
  2022年   102篇
  2021年   215篇
  2020年   164篇
  2019年   224篇
  2018年   295篇
  2017年   207篇
  2016年   216篇
  2015年   275篇
  2014年   379篇
  2013年   558篇
  2012年   889篇
  2011年   938篇
  2010年   513篇
  2009年   516篇
  2008年   847篇
  2007年   885篇
  2006年   879篇
  2005年   894篇
  2004年   882篇
  2003年   753篇
  2002年   734篇
  2001年   111篇
  2000年   92篇
  1999年   114篇
  1998年   142篇
  1997年   125篇
  1996年   86篇
  1995年   67篇
  1994年   58篇
  1993年   60篇
  1992年   45篇
  1991年   31篇
  1990年   42篇
  1989年   38篇
  1988年   29篇
  1987年   29篇
  1986年   31篇
  1985年   32篇
  1984年   29篇
  1983年   29篇
  1982年   25篇
  1981年   25篇
  1980年   21篇
  1979年   14篇
  1978年   16篇
  1977年   12篇
  1976年   17篇
  1973年   13篇
  1970年   18篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Cardiovascular changes have been noted to occur during movement from the operating room or recovery room (RR) to the intensive care unit (ICU). This study examined blood pressure changes and related variables during transport from the RR to the ICU in 135 postoperative acoustic tumor patients. Although there was no significant change in blood pressure values from the RR to the ICU, patients with pre-existing hypertension and elevated RR blood pressures were noted to have an increased frequency of postoperative complications. In addition, a relationship was noted between administration of halothane and frequency of postoperative complications. Results highlight the need for nurses not only to monitor, but also closely control postoperative blood pressure in this population.  相似文献   
32.
H. Steve White  PhD 《Headache》2005,45(S1):S48-S56
Topiramate is a neuromodulatory compound with stabilizing properties that was initially introduced for the management of partial seizures. Topiramate has been demonstrated to modify several receptor-gated and voltage-sensitive ion channels, including voltage-activated Na+ and Ca2+ channels and non-NMDA receptors. These receptors have been implicated in the pathophysiology of both epilepsy and migraine. The pharmacological mechanisms of action for topiramate that may explain its antiepileptic and migraine preventive activities will be discussed in this review. In addition, the potential relationship between the molecular activities of topiramate and its efficacy in epilepsy and migraine prevention will be emphasized.  相似文献   
33.
Parkinson's disease is a neurodegenerative movement disorder that results from progressive loss of midbrain dopamine neurons, which consequently leads to hyperactivity of subthalamic neurons.  相似文献   
34.
To address the need for management development in public health, the Centers for Disease Control and Prevention (CDC) established three independent workforce development initiatives aimed primarily at strengthening management and leadership capacity: the Sustainable Management Development Program, the Management Academy for Public Health, and the CDC Leadership and Management Institute. Though independently designed and implemented, the programs share similar guiding principles in their approach to management development: interactive (adult) learning, management tools that reinforce evidence-based decision making, individual feedback, continuous improvement of the learning process, posttraining support for networking and life-long learning, and teamwork. This article will discuss important lessons learned regarding best practices in management and leadership development.  相似文献   
35.
A device called the Dex Frame has recently been marketed as an aid for children with specific learning difficulties. Using a test of reading speed and a test of reading accuracy we have attempted to evaluate the device. Two groups of children with learning difficulties were used, one having sole use of the device and being allowed to carry it with them and a second group who only used the device when attending for remedial tuition and assessment. The results show that no significant improvement occurred in reading performance of the groups with learning difficulties using the Dex Frame as compared with a control group. The teachers of the groups did, however, feel that on an individual basis some children (< 10%) expressed that they felt more comfortable using the device.  相似文献   
36.
Eighteen patients with chronic constipation were diagnosed as having paradoxical puborectalis contraction (PPC) as the cause for their constipation. The diagnosis of PPC was made after office evaluation, colonic transit study, manometry, cinedefecography, and electromyography (EMG). These 18 patients had a mean duration of symptoms of 26.9 years; none of these patients had unassisted bowel movements. Fourteen patients had a mean of 4.6 laxative-induced bowel evacuations per week, and 11 patients had a mean of 4.4 enema-induced bowel evacuations per week. Patients underwent a mean of 8.9 one-hour EMG-based biofeedback sessions. At a mean follow-up of 9.1 (range, 0.5–12) months, these 18 patients had a mean of 7.3 unassisted bowel actions per week ( P <0.0001). In addition, persistent laxative use was reported by only two patients, and, in both cases, this was once a week or less ( P <0.001). Similarly, enema use was reported by only three patients, one once weekly and the other two thrice weekly ( P <0.002). No biofeedback-related complications were identified. EMG-based biofeedback is a valuable technique associated with an 89 percent success rate in the treatment of PPC.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991.  相似文献   
37.
38.
This investigation used a derivation of acoustic reflection (AR) technology to make cross-sectional measurements of changes due to aging in the oral and pharyngeal lumina of male and female speakers. The purpose of the study was to establish preliminary normative data for such changes and to obtain acoustic measurements of changes due to aging in the formant frequencies of selected spoken vowels and their long-term average spectra (LTAS) analysis. Thirty-eight young men and women and 38 elderly men and women were involved in the study. The oral and pharyngeal lumina of the participants were measured with AR technology, and their formant frequencies were analyzed using the Kay Elemetrics Computerized Speech Lab. The findings have delineated specific and similar patterns of aging changes in human vocal tract configurations in speakers of both genders. Namely, the oral cavity length and volume of elderly speakers increased significantly compared to their young cohorts. The total vocal tract volume of elderly speakers also showed a significant increment, whereas the total vocal tract length of elderly speakers did not differ significantly from their young cohorts. Elderly speakers of both genders also showed similar patterns of acoustic changes of speech production, that is, consistent lowering of formant frequencies (especially F1) across selected vowel productions. Although new research models are still needed to succinctly account for the speech acoustic changes of the elderly, especially for their specific patterns of human vocal tract dimensional changes, this study has innovatively applied the noninvasive and cost-effective AR technology to monitor age-related human oral and pharyngeal lumina changes that have direct consequences for speech production.  相似文献   
39.
40.
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