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   1149篇
  免费   58篇
  国内免费   3篇
耳鼻咽喉   7篇
儿科学   23篇
妇产科学   28篇
基础医学   161篇
口腔科学   8篇
临床医学   103篇
内科学   396篇
皮肤病学   5篇
神经病学   57篇
特种医学   23篇
外科学   161篇
综合类   5篇
预防医学   68篇
眼科学   40篇
药学   67篇
中国医学   19篇
肿瘤学   39篇
  2023年   10篇
  2022年   20篇
  2021年   64篇
  2020年   19篇
  2019年   49篇
  2018年   57篇
  2017年   24篇
  2016年   30篇
  2015年   40篇
  2014年   52篇
  2013年   58篇
  2012年   80篇
  2011年   86篇
  2010年   30篇
  2009年   26篇
  2008年   55篇
  2007年   57篇
  2006年   51篇
  2005年   49篇
  2004年   49篇
  2003年   33篇
  2002年   44篇
  2001年   26篇
  2000年   32篇
  1999年   25篇
  1998年   9篇
  1997年   6篇
  1996年   4篇
  1995年   8篇
  1994年   5篇
  1992年   13篇
  1991年   7篇
  1990年   9篇
  1989年   5篇
  1988年   5篇
  1987年   5篇
  1986年   4篇
  1985年   10篇
  1984年   3篇
  1983年   8篇
  1982年   4篇
  1975年   3篇
  1974年   2篇
  1973年   4篇
  1972年   5篇
  1971年   4篇
  1970年   5篇
  1969年   3篇
  1967年   3篇
  1966年   2篇
排序方式: 共有1210条查询结果,搜索用时 15 毫秒
31.
Maesa saponins with the 13,28‐epoxy‐oleanane triterpene core skeleton were described recently to possess strong and selective in vitro and in vivo antileishmania activity. In the absence of direct chemical derivatization possibilities, a structure‐based literature search was carried out to explore a structure‐activity relationship. Crude alcohol extracts from several plant species of Myrsinaceae, Primulaceae, Aceraceae and Icacinaceae were evaluated for in vitro activity against Leishmania infantum intracellular amastigotes and cytotoxicity on MRC‐5SV2 cells, while the saponin content was evaluated qualitatively by TLC. A clear correlation was found between the presence of close analogue 13,28‐epoxy‐oleanane triterpene saponins and potent and selective antileishmania activity. This was most striking in Maesa species, except for M. macrosepala. Interesting activities were also found in extracts that did not exactly match the TLC characteristics of the Maesa saponin references, as was the case for Ardisia angusta, A. amherstiana, A. caudata, A. gigantifolia, A. roseiflora, Myrsine affinis, Acer brevipes and A. laurinum var. petelotii. This study indicates that the 13,28‐epoxy‐oleanane triterpene moiety is essential for selective antileishmania potential and that several other plant species could still be explored for antileishmania drug discovery. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
32.
INTRODUCTION AND OBJECTIVES: Coronary flow reserve (CFR) is impaired not only in ischemic heart disease, but also in cardiac diseases that may or may not course with heart failure. The aim of the present study was to determine if the severity of heart failure can influence CFR impairment. METHODS: Forty patients with non-ischemic heart disease and heart failure were studied 41 times. Four groups were established: 1. 10 patients in functional class III-IV; 2. 10 patients in functional class II not taking beta-blockers; 3. 11 patients in class II treated with carvedilol, and 4. 10 patients in class I. These patients had a history of heart failure and systolic dysfunction. Myocardial blood flow (MBF) was measured with positron emission tomography (PET) and N-13 ammonia at rest (r) and during adenosine triphosphate (ATP) infusion. RESULTS: MBF and CFR were significantly higher in group 4 (1.95 0.58 and 2.40 0.95 ml/min/g) than in group 1 (1.02 0.52 and 1.46 0.48 ml/min/g). CFR tended to be higher in groups 2 (1.73 0.72), and 3 (1.89 0.75) vs group 1. No significant correlation was found between CFR and the following variables: age, systolic blood pressure, ventricular mass index, ventricular volume indexes, and ejection fraction. CONCLUSIONS: Coronary microvascular function is impaired in non-ischemic heart failure, and the impairment is related to functional class, regardless of the underlying responsible heart disease.  相似文献   
33.
34.
35.
36.
37.

Objective

To determine if there is a correlation between self-perception and self- efficacy in the development of learning abilities associated with the care of the critically ill patient in a Clinical Environment of High Fidelity Simulation, as part of the training for nursing students in the field of Life Support.

Method

Quasi-experimental study carried out in academic year 2014-2015 with two groups of Nursing Degree students, and applying pre/post measurement tests. The students were subjected to the same simulation experience, that of a critical patient with a possible progression to cardiac arrest. Simulation training, self-perception, and self-efficacy were used as theoretical framework, as well as the latest recommendations by European Resuscitation Council.

Results

A significant increase in self-perception for the development of competences associated with a critical situation was observed in both groups. As for self-perception and self-efficacy, some variations were found between the groups.

Conclusions

The results found allow us to recommend clinical simulation for the training of students in critically ill patients, since there is a significant increase in the level of self-perception for the development of competences associated with critical care. Likewise, clinical simulation provides a positive link between self-perception and self-confidence in the students.  相似文献   
38.

Objective

To test the feasibility, safety and effectiveness of a 12-wk whole body vibration (WBV) intervention on glycemic control, lipid-related cardiovascular risk factors and functional capacity among type 2 diabetes mellitus (T2DM) patients in a primary care context.

Methods

Fifty non-insulin dependent T2DM patients were randomized 1:1 to an intervention group that, in addition to standard care, received a 12-wk WBV intervention, and a control group receiving only standard care (from February 2012 through May 2012). Outcomes, including glycated hemoglobin (HbA1c), fasting blood glucose, lipid-related cardiovascular risk factors (i.e., cholesterol, triglycerides, lipoproteins, LDL/HDL and atherogenic index) and functional capacity were measured at baseline and after the 12-wk intervention.

Results

After intervention, there was a reduction in HbA1c and fasting blood glucose when compared to the control group, with a mean difference in change scores between groups of −0.55% (95% CI −0.15 to −0.76) and −33.95 mm/dl (95% CI −51.38 to −3.47), respectively. Similarly, most lipid-related cardiovascular risk factors (i.e., cholesterol, triglycerides and atherogenic index) were also reduced (p < 0.05).

Conclusion

A 12-wk WBV intervention in a primary care context is feasible, safe and effective in improving glycemic profile, lipid-related cardiovascular risk factors and functional capacity among T2DM patients.

Trial number

ACTRN12613000021774.  相似文献   
39.
40.
Brito FF  Mur P  Barber D  Lombardero M  Galindo PA  Gómez E  Borja J 《Allergy》2002,57(12):1191-1194
BACKGROUND: The family Dermestidae belongs to the order Coleoptera. Occupational allergy has been described in museum personnel. A 31-year-old male wool worker presenting rhinoconjunctivitis and asthma episodes probably linked to exposure to Dermestidae-infected wool was investigated. METHODS: Extracts prepared either from insect bodies or from dust from parasitized wool were used for skin prick testing (SPT), conjunctival and bronchial provocation tests and in vitro determinations. RESULTS: SPT and provocation tests were positive to both extracts. PEFR measurement demonstrated the association between the patient's symptoms and occupational exposure to Dermestidae. Specific IgE to both extracts was detected and immunoblotting revealed several protein bands from 5 to 200 kDa that were reactive to IgE from the patient's serum. CONCLUSIONS: Dermestidae exposure in wool workers when handling parasitized wool can be a cause of IgE-mediated rhinoconjunctivitis and asthma.  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