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   1139322篇
  免费   84471篇
  国内免费   3165篇
耳鼻咽喉   14582篇
儿科学   37953篇
妇产科学   30765篇
基础医学   163884篇
口腔科学   30778篇
临床医学   104381篇
内科学   223249篇
皮肤病学   25810篇
神经病学   92284篇
特种医学   44635篇
外国民族医学   319篇
外科学   172020篇
综合类   25395篇
一般理论   488篇
预防医学   88384篇
眼科学   25597篇
药学   80980篇
  3篇
中国医学   2245篇
肿瘤学   63206篇
  2021年   9929篇
  2019年   10103篇
  2018年   13766篇
  2017年   10742篇
  2016年   12201篇
  2015年   13817篇
  2014年   18956篇
  2013年   28178篇
  2012年   38173篇
  2011年   40654篇
  2010年   24219篇
  2009年   22906篇
  2008年   37544篇
  2007年   39606篇
  2006年   40003篇
  2005年   38771篇
  2004年   37273篇
  2003年   35519篇
  2002年   34249篇
  2001年   48757篇
  2000年   49592篇
  1999年   42099篇
  1998年   12919篇
  1997年   11491篇
  1996年   11347篇
  1995年   10882篇
  1994年   10080篇
  1993年   9399篇
  1992年   33325篇
  1991年   32440篇
  1990年   31869篇
  1989年   30676篇
  1988年   27930篇
  1987年   28068篇
  1986年   26183篇
  1985年   25338篇
  1984年   19194篇
  1983年   16196篇
  1982年   10125篇
  1981年   9135篇
  1979年   17423篇
  1978年   12776篇
  1977年   10783篇
  1976年   10203篇
  1975年   10555篇
  1974年   12745篇
  1973年   12221篇
  1972年   11217篇
  1971年   10364篇
  1970年   9622篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.

Background

The ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials showed that the adjuvanted recombinant zoster vaccine (RZV) was ≥90% efficacious in preventing herpes zoster in adults. Here we present a comprehensive overview of the safety data from these studies.

Methods

Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomly vaccinated with RZV or placebo. Safety analyses were performed on the pooled total vaccinated cohort, consisting of participants receiving at least one dose of RZV or placebo. Solicited and unsolicited adverse events (AEs) were collected for 7 and 30?days after each vaccination, respectively. Serious AEs (SAEs) were collected from the first vaccination until 12?months post-last dose. Fatal AEs, vaccination-related SAEs, and potential immune-mediated diseases (pIMDs) were collected during the entire study period.

Results

Safety was evaluated in 14,645 RZV and 14,660 placebo recipients. More RZV than placebo recipients reported unsolicited AEs (50.5% versus 32.0%); the difference was driven by transient injection site and solicited systemic reactions that were generally seen in the first week post-vaccination. The occurrence of overall SAEs (RZV: 10.1%; Placebo: 10.4%), fatal AEs (RZV: 4.3%; Placebo: 4.6%), and pIMDs (RZV: 1.2%; Placebo: 1.4%) was balanced between groups. The occurrence of possible exacerbations of pIMDs was rare and similar between groups. Overall, except for the expected local and systemic symptoms, the safety results were comparable between the RZV and Placebo groups irrespective of participant age, gender, or race.

Conclusions

No safety concerns arose, supporting the favorable benefit-risk profile of RZV.  相似文献   
92.
Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.  相似文献   
93.
94.
95.
Patients have become increasingly well informed with higher expectations to be involved in decision-making processes regarding their care and treatment. However, few studies have examined the impact of patient involvement on health care providers’ partnership-building communication. The aim of this study was to measure and explore the self-reported effects of patient involvement on the work of physicians and nurses. A questionnaire survey was distributed among cardiology staff in 12 Swedish hospitals (N = 488, response rate 67%). The sample was comprised of registered nurses (RNs, n = 303), licensed practical nurses (LPNs, n = 132), and physicians (MDs, n = 53). Confirmatory factor analysis was used to examine seven questionnaire statements concerning implications of patient involvement for one’s clinical work. Regression analyses were used to examine factors associated with staff’s partnership-building communication. Analysis confirmed two distinct factors accounting for 57% of the total variance, representing both negative—“Hassles”and positive—“Uplifts”aspects of patient involvement. Regression analyses revealed that only positive aspects (i.e., uplifts) of patient involvement predicted staff behavior aimed at involving patients. Working with actively involved patients may be a source of stress, both negative and positive, for health care professionals. By developing work routines for involving patients in their care, health care workplaces may help health care professionals to buffer the negative effects, and enhance the positive effects, of that stress.  相似文献   
96.
Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries.  相似文献   
97.
We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa’s environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly.  相似文献   
98.
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