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   1873篇
  免费   155篇
耳鼻咽喉   8篇
儿科学   75篇
妇产科学   45篇
基础医学   187篇
口腔科学   20篇
临床医学   183篇
内科学   446篇
皮肤病学   10篇
神经病学   208篇
特种医学   82篇
外科学   149篇
综合类   28篇
一般理论   117篇
预防医学   223篇
眼科学   52篇
药学   103篇
肿瘤学   92篇
  2023年   11篇
  2022年   14篇
  2021年   33篇
  2020年   13篇
  2019年   25篇
  2018年   35篇
  2017年   30篇
  2016年   21篇
  2015年   28篇
  2014年   30篇
  2013年   55篇
  2012年   63篇
  2011年   90篇
  2010年   56篇
  2009年   49篇
  2008年   89篇
  2007年   59篇
  2006年   69篇
  2005年   72篇
  2004年   74篇
  2003年   61篇
  2002年   51篇
  2001年   55篇
  2000年   74篇
  1999年   62篇
  1998年   21篇
  1997年   22篇
  1996年   30篇
  1995年   26篇
  1994年   23篇
  1993年   24篇
  1992年   52篇
  1991年   53篇
  1990年   53篇
  1989年   60篇
  1988年   44篇
  1987年   41篇
  1986年   50篇
  1985年   47篇
  1984年   24篇
  1983年   17篇
  1982年   22篇
  1981年   15篇
  1980年   15篇
  1979年   18篇
  1977年   16篇
  1976年   18篇
  1975年   17篇
  1967年   13篇
  1966年   17篇
排序方式: 共有2028条查询结果,搜索用时 46 毫秒
61.
Over a decade of research in health literacy has provided evidence of strong links between literacy skills of patients and health outcomes. At the same time, numerous studies have yielded insight into efficacious action that health providers can take to mitigate the negative effects of limited literacy. This small study focuses on the adaptation, review and use of two new health literacy toolkits for health professionals who work with patients with two of the most prevalent chronic conditions, arthritis and cardiovascular disease. Pharmacists have a key role in communicating with patients and caregivers about various aspects of disease self-management, which frequently includes appropriate use of medications. Participating pharmacists and staff offered suggestions that helped shape revisions and reported positive experiences with brown bag events, suggestions for approaches with patients managing chronic diseases, and with concrete examples related to several medicines [such as Warfarin©] as well as to common problems [such as inability to afford needed medicine]. Although not yet tested in community pharmacy sites, these publically available toolkits can inform professionals and staff and offer insights for communication improvement.  相似文献   
62.
63.
64.
65.
66.
The pathogenesis of oxygen toxicity remains unknown but may involve leukocyte mediated injury. The effects of hyperoxia on several lower respiratory tract parameters were examined in bronchoalveolar lavage fluid of normal nonsmoking subjects who inhaled a fractional inspired oxygen concentration of 50 percent (mean exposure: 44 h). Evidence that 50 percent O2 produced oxidative stress in the lung included recovery of fluorescent products of lipid peroxidation and partial oxidation of alpha 1-antitrypsin in BAL fluid obtained after O2 exposure. To examine whether alveolar macrophage-derived leukotriene B4 may be generated in response to 50 percent O2, AM were isolated from O2-exposed subjects and compared with AM recovered from subjects breathing room air. Leukotriene B4 levels were elevated in supernatants from both unstimulated and arachidonic acid-stimulated AM obtained from hyperoxia-exposed subjects. In hyperoxia-exposed individuals, LTB4 levels were also elevated in extracted BAL fluid. The percentage of BAL neutrophils was also significantly increased after O2 exposure (2.8 +/- 0.6 vs 1.2 +/- 0.4 percent, p = 0.05). We conclude that an FIO2 of 50 percent inhaled for 44 h is associated with enhanced oxidative stress, stimulation of AM to release LTB4, and a small but significantly increased percentage of neutrophils recovered in BAL fluid.  相似文献   
67.
68.
Sinoaortic baroreceptor denervation is reported to produce exaggerated centrally derived cardiovascular and endocrine responses. We examined the effect of sinoaortic denervation (SAD) on the cardiovascular and endocrine responses to two acute stressors, footshock and immobilization, in male Sprague-Dawley rats. Parameters measured were mean arterial pressure (MAP), heart rate (HR) and plasma levels of oxytocin (OT) and vasopressin (VP). Baseline MAP was elevated in the SAD group (approximately 25 mm Hg) and footshock stress increased arterial pressure equivalently in both groups. This stress caused tachycardia and increased plasma OT, with a tendency for the SAD group to show blunted responses. Immobilization increased HR but caused no change in MAP and no significant difference between the groups. This form of stress also increased plasma OT, and again the SAD group showed a diminished response. Plasma VP was not significantly altered by either stressor. The results of these studies indicate that SAD does not uniformly increase the cardiovascular and endocrine responses to all stressors or centrally derived stimuli. These results also suggest that the lack of an increase in plasma VP is not related to baroreceptor-mediated inhibition of secretion under stressful conditions.  相似文献   
69.
We reviewed the records of the Mayo Clinic patients with known carcinoid syndrome in whom echocardiographic studies had been done. Nineteen patients had M-mode and 2-dimensional echocardiographic examinations, and 1 patient had an M-mode examination only. Of the 20 patients, 8 had no evidence by echocardiogram of carcinoid heart disease; 2 had changes in the tricuspid valve echogram suggestive of early carcinoid heart disease, and the other 10 patients had the following distinctive echocardiographic findings: (1) the pattern of right ventricular volume overload (enlarged right ventricle with abnormal septal motion); (2) abnormal right-sided valves, including (a) a striking appearance of the tricuspid valve, the leaflets appearing thickened, retracted, and fixed in a semiopen position throughout the cardiac cycle, and (b) thickened, retracted pulmonic valve cusps, when visualized; and (3) the left-sided valves and chambers rarely involved. These echocardiographic features are distinctive of advanced carcinoid heart disease and correlate closely with pathologic findings.  相似文献   
70.
PURPOSE: To evaluate the effectiveness of oral corticosteroid therapy in patients with stable chronic obstructive pulmonary disease. DATA IDENTIFICATION: An English-language literature search using MEDLINE (1966 to 1989) and a bibliographic review of all retrieved articles identified 33 original studies of oral corticosteroid use in chronic obstructive pulmonary disease published since 1951. STUDY SELECTION: We submitted a photocopy of each study's "methods" section to three nonstudy physician-investigators who used nine explicit criteria to independently assess study quality. Ten studies met all criteria and five studies met some of the criteria. DATA EXTRACTION: To compare outcomes across all qualifying studies, we defined response to therapy as a 20% or greater increase in the baseline forced expiratory volume in 1 second (FEV1); we defined the treatment effect size for each study as the proportion of patients who responded to corticosteroid therapy minus the proportion of patients who responded to placebo. Potential confounding variables as related to eligibility criteria and treatment protocols were also assessed for each study. RESULTS OF DATA SYNTHESIS: Among ten studies that met all nine criteria, we found no significant differences in eligibility criteria, treatment protocol, or study design. No association was found between treatment effect size and publication date, study size, mean patient age, or FEV1. These studies had reported effect sizes ranging from 0% to 56%; we calculated a weighted mean effect size of 10% (95% CI, 2% to 18%). When studies meeting only some of the criteria were included in the calculation, the weighted mean effect size was 11% (95% CI, 4% to 18%). CONCLUSIONS: Patients with stable chronic obstructive pulmonary disease receiving oral corticosteroid therapy have a 20% or greater improvement in baseline FEV1 approximately 10% more often than similar patients receiving placebo.  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