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   10247篇
  免费   736篇
  国内免费   37篇
耳鼻咽喉   77篇
儿科学   293篇
妇产科学   293篇
基础医学   1380篇
口腔科学   233篇
临床医学   1274篇
内科学   2036篇
皮肤病学   259篇
神经病学   1080篇
特种医学   184篇
外科学   893篇
综合类   64篇
一般理论   16篇
预防医学   1306篇
眼科学   181篇
药学   682篇
中国医学   32篇
肿瘤学   737篇
  2024年   16篇
  2023年   132篇
  2022年   225篇
  2021年   462篇
  2020年   263篇
  2019年   359篇
  2018年   375篇
  2017年   273篇
  2016年   314篇
  2015年   316篇
  2014年   393篇
  2013年   579篇
  2012年   829篇
  2011年   821篇
  2010年   472篇
  2009年   372篇
  2008年   632篇
  2007年   620篇
  2006年   569篇
  2005年   540篇
  2004年   455篇
  2003年   438篇
  2002年   389篇
  2001年   42篇
  2000年   34篇
  1999年   39篇
  1998年   68篇
  1997年   68篇
  1996年   60篇
  1995年   51篇
  1994年   40篇
  1993年   45篇
  1992年   32篇
  1991年   31篇
  1990年   26篇
  1989年   24篇
  1988年   27篇
  1987年   28篇
  1986年   25篇
  1985年   26篇
  1984年   33篇
  1983年   39篇
  1982年   35篇
  1981年   35篇
  1980年   41篇
  1979年   13篇
  1978年   17篇
  1977年   18篇
  1975年   14篇
  1973年   15篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
End-stage renal disease (ESRD) under hemodialyses (HD) is related with a higher propensity to infections, essentially due to T-cell lymphopenia. We postulated that HD procedure affects CD4(+) T cells, especially by inducing apoptotic death and that recombinant human erythropoietin (rhEPO) therapy may also play an important role in the modulation of the immune system in these patients. T-cell phenotype and apoptosis of HD patients and healthy controls were evaluated by flow cytometry using anticoagulated whole-blood samples. In 12 HD patients, these parameters were also analyzed before and immediately after HD procedure. HD patients showed a decrease in total circulating CD3(+) lymphocytes, especially in CD4(+) T cells (0.747 ± 0.410 vs. 0.941 ± 0.216 × 10(9)/L, p < 0.05), which could be a consequence of the higher proportion of CD3(+) and CD4(+) lymphocytes in the latest stage of apoptosis (or death) and of the higher proportion of apoptotic CD4(+) T cells observed in the patients immediately after HD procedure (2.91 ± 0.780 vs. 3.90 ± 1.96, p < 0.05). A positive and statistically significant correlation between CD3(+) and CD4(+) lymphocytes in latest stage of apoptosis (or death) with HD time was found (CD3(+): r = 0.592, p < 0.01; CD4(+): r = 0.501, p < 0.01). We also found a negative and significant correlation between weekly rhEPO doses and the number of CD4(+) T cells (r = -0.358, p < 0.05). In conclusion, HD procedure still contributes to the development of T-cell lymphopenia, at least in part, by apoptosis induction. It was also shown that rhEPO therapy is associated with the CD4(+) T-cell decline, possibly by immune modulation, eliminating atypical cells and helping to restore the CD4(+) T-cell subset.  相似文献   
82.
83.
Quality-of-life indicators for dysphagia provide invaluable information to the treating clinician regarding the success or failure of swallowing therapy. The purpose of this study was to develop a clinically efficient, statistically robust patient-reported outcomes tool that measures the handicapping effect of dysphagia on emotional, functional, and physical aspects of individual’s lives. 60 statements describing the handicapping effect of dysphagia were collected from patient reports and divided into subscales of physical, emotional, and functional problems. The statements were presented to 77 individuals with dysphagia. Respondents replied never, sometimes, or always to each statement and rated their self-perceived dysphagia severity on a 7-point equal-appearing interval scale. Cronbach’s α was performed to assess the internal consistency validation of the items within the questionnaire. The final questionnaire was reduced to 25 items and administered to 214 individuals with dysphagia and 74 controls. Test–retest was performed on 63 individuals with dysphagia. Cronbach’s α for the initial and final versions was strong at r = 0.96 and r = 0.94, respectively. Significant differences occurred between the dysphagia and control groups. Test–retest reliability was strong. We present a new, easy-to-complete, statistically robust, patient-reported outcomes measure for assessing the handicapping effect of dysphagia.  相似文献   
84.
85.
86.
The ability of nurses to adopt and successfully use EMR is expected to have a significant impact on achieving benefits such as reduction in healthcare costs and improvement in healthcare quality. A review of the current research literature reveals issues and concerns relating to the adoption and use of EMR by nurses in hospital environments. This article presents a literature review of such issues and concerns, and suggests a framework for enhancing the adoption and use of EMR by nurses and hospitals.  相似文献   
87.
Eating disorders and obesity (EDO) are increasing among youth, having serious long-term physical and psychological consequences. The purpose of this study was to determine if significant differences exist in EDO risk factors following participation of 4–6th grade students in a school-based EDO prevention curriculum. This community-based research project assessed students at baseline and one week following EDO intervention. Primary outcome variables measured self-esteem, body dissatisfaction, and high risk eating attitudes and behaviors. Pre and post-test differences were calculated using mixed models, correcting for clustering within schools and teachers. This study found mean changes in all scores in healthy directions, as well as movement of students into lower risk groups post-intervention. This program demonstrated that a classroom curriculum is associated with decreased risks of EDO in boys and girls, supporting prevention programs at an early age for both sexes. Studies to determine long term benefit and guide booster interventions are warranted.  相似文献   
88.
Flk-1(+) endothelial progenitors contribute critically to the definitive onset of hematopoiesis during embryogenesis. Recent studies have suggested that adult sources of endothelial cells also possess hematopoietic activity. In this study, we sought to determine whether transplantation of primary vascular endothelial cells (ECs) could enhance the hematopoietic recovery and survival of irradiated mice. C57Bl6 mice were exposed to sublethal and lethal doses of irradiation and were subsequently given transplants of either primary murine brain-derived ECs (MBECs) or fetal blood-derived ECs (FBECs). Mice that received a transplant with MBECs alone demonstrated accelerated BM cellular recovery, radioprotection of BM c-kit(+)sca-1(-)lin(-) progenitors and enhanced regeneration of c-kit(+)sca-1(+)lin(-) (KSL) stem/progenitor cells following irradiation compared with controls. MBEC transplantation also facilitated the recovery of circulating white blood cell and platelet counts following radiation exposure. Remarkably, 57% of mice that received a transplant with MBECs alone survived long term following 1050 cGy exposure, which was 100% lethal in control mice. FBEC transplantation was also associated with increased survival compared with controls, although these mice did not survive in the long term. These data suggest that reestablishment of endothelial cell activity can improve the hematopoietic recovery and survival of irradiated mice.  相似文献   
89.
In part 1, published last month, causes and clinical features of congestive heart failure in infancy were discussed, and some of the more common malformations were illustrated. In this portion, principles of management and recommendations for specific therapy are presented. Particularly emphasized is digitalization, the most important step in treating the infant with heart failure.  相似文献   
90.
Background. The Public Access Defibrillation (PAD) Trial found an overall doubling in the number of out-of-hospital cardiac arrest (CA) survivors when a lay responder team was equipped with an automated external defibrillator (AED), compared with cardiopulmonary resuscitation (CPR) alone. Objectives. To describe the types of facilities that participated in the trial andto report the incidence of CA andsurvival in these different types of facilities. Methods. In this post-hoc analysis of PAD Trial data, the physical characteristics of the participating facilities andthe numbers of presumed CAs, treatable CAs, andsurvivors are reported for each category of facilities. Results. There were 625 presumed CAs at 1,260 participating facilities. Just under half (n = 291) of the presumed CAs were classified as treatable CAs. Treatable CAs occurred at a rate of 2.9 per 1,000 person-years of exposure; rates were highest in fitness centers (5.1) andgolf courses (4.8) andlowest in office complexes (0.7) andhotels (0.7). Survival from treatable CA was highest in recreational complexes (0.5), public transportation sites (0.4), andfitness centers (0.4) andlowest in office complexes (0.1) andresidential facilities (0.0). Conclusions. During the PAD Trial, the exposure-adjusted rate of treatable CA was highest in fitness centers andgolf courses, but the incidence per facility was low to moderate. Survival from treatable cardiac arrest was highest in recreational complexes, public transportation facilities, andfitness centers.  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