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   1409189篇
  免费   100591篇
  国内免费   1924篇
耳鼻咽喉   18298篇
儿科学   45031篇
妇产科学   38475篇
基础医学   210067篇
口腔科学   39805篇
临床医学   126444篇
内科学   279726篇
皮肤病学   31215篇
神经病学   113788篇
特种医学   50264篇
外国民族医学   266篇
外科学   194842篇
综合类   26437篇
现状与发展   3篇
一般理论   590篇
预防医学   122087篇
眼科学   31825篇
药学   103886篇
  36篇
中国医学   2624篇
肿瘤学   75995篇
  2021年   12141篇
  2019年   12752篇
  2018年   18035篇
  2017年   13220篇
  2016年   14120篇
  2015年   16186篇
  2014年   21545篇
  2013年   32811篇
  2012年   46807篇
  2011年   49676篇
  2010年   27912篇
  2009年   25877篇
  2008年   45644篇
  2007年   48789篇
  2006年   47983篇
  2005年   46775篇
  2004年   44616篇
  2003年   42524篇
  2002年   41061篇
  2001年   59574篇
  2000年   61061篇
  1999年   51185篇
  1998年   13998篇
  1997年   12651篇
  1996年   13035篇
  1995年   12274篇
  1994年   11395篇
  1992年   39887篇
  1991年   39212篇
  1990年   37971篇
  1989年   36577篇
  1988年   33990篇
  1987年   33224篇
  1986年   31756篇
  1985年   29939篇
  1984年   22798篇
  1983年   19899篇
  1982年   11745篇
  1979年   21909篇
  1978年   16075篇
  1977年   13439篇
  1976年   12456篇
  1975年   13549篇
  1974年   16514篇
  1973年   16318篇
  1972年   15425篇
  1971年   14438篇
  1970年   13619篇
  1969年   12977篇
  1968年   12162篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
Background: The EMCDDA, through its network of National Focal Points, collects information on the quality assurance systems for drugs-related interventions across European countries. European National Drug Strategies include recommendations for systems and approaches for the assurance of the quality of interventions.

Methods: We searched National Drug Strategies for elements related to quality assurance in drug demand reduction and summarised information through questionnaires administered to the EMCDDA Network of National Focal Points.

Results: In total, 15 National Drug Strategies and 60 questionnaires were analysed. Almost all the strategies include quality-related topics. Frequently, the Ministry of Health leads quality assurance although sometimes jointly with the Ministries of Education, Labour, Family and Social Welfare. Accreditation systems are common, but implemented in different ways. Training and education are widely provided, for the vast majority of countries, consisting of short-term training to keep professionals updated. Guidelines and Standards are gathering momentum as the major tools for the implementation of evidence-based recommendations and are usually available across countries.

Conclusions: Although the evidence base for interventions in drug demand reduction is becoming available and accepted, attention needs to be given to implementation issues. The European countries are rapidly moving towards paying greater attention to the quality of interventions.  相似文献   
95.
Background: Excessive drinking is commonplace at UK Universities. Individuals may misperceive how much they drink compared to others and are less likely to think that they will suffer adverse consequences. Young people often distance themselves and their friends from ‘problem drinkers’. Objectives: The aim of the study was to explore how student drinkers compared their own drinking behaviors to the drinking behaviors of others. Methods: An online survey was completed by 416 students aged 18–30 (68.5% female). They were asked ‘how do you think your drinking compares with other people like you?' and ‘how do you think your behavior when you drink compares with other people like you?’ Answers were subjected to thematic analysis. Results: The first main theme was about ‘identification as a ‘good’ drinker’. Participants suggested their own behavior when drinking was similar to their sober behavior. Further, they viewed themselves as more able to maintain a balance between staying in control and having fun while drinking. The second main theme was about ‘distancing from being a ‘bad’ drinker. Participants distanced themselves from negative prototypical drinkers, such compulsive or anti-social drinkers. They also attributed their own drinking behaviors to situational factors, but described other people as intentionally violent or aggressive. Conclusions/Importance: These findings may explain the failure of some health messages to change drinking behaviors. If drinkers perceive that their behavior when they drink is better than other people's then they may discount intervention messages. Targeting these biases could be incorporated into future interventions.  相似文献   
96.
Pharmaceuticals are ubiquitous in the natural environment with concentrations expected to rise as human population increases. Environmental risk assessments are available for a small portion of pharmaceuticals in use, raising concerns over the potential risks posed by other drugs that have little or no data. With >1900 active pharmaceutical ingredients in use, it would be a major task to test all of the compounds with little or no data. Desk-based prioritization studies provide a potential solution by identifying those substances that are likely to pose the greatest risk to the environment and which, therefore, need to be considered a priority for further study. The aim of this review was to (1) provide an overview of different prioritization exercises performed for pharmaceuticals in the environment and the results obtained; and (2) propose a new holistic risk-based prioritization framework for drugs in the environment. The suggested models to underpin this framework are discussed in terms of validity and applicability. The availability of data required to run the models was assessed and data gaps identified. The implementation of this framework may harmonize pharmaceutical prioritization efforts and ensure that, in the future, experimental resources are focused on molecules, endpoints, and environmental compartments that are biologically relevant.  相似文献   
97.
Introduction: Diabetes Mellitus has been considered an epidemic by the World Health Organization, with a high risk of morbidity and mortality. The treatment of this pathology consists in glycemic control, which can be done by oral hypoglycemic agents, insulin therapy, dietary guidance, regular physical activity, and psychosocial support. In addition, other adjuvant treatments are employed, such as phytotherapic, and one of the most used plants is Bauhinia forficata.

Areas covered: In the current review, patents using Bauhinia forficata for the Diabetes Mellitus treatment have been analyzed. There were 03 patents in WIPO, 01 in Espacenet, 01 in USPTO, and 02 in INPI.

Expert opinion: Patents on the adjuvant treatment of Diabetes Mellitus by Bauhinia forficata are discussed. Although there are some phytotherapy products containing this medicinal plant which has hypoglycemic effect here is still a need for the development of more products based on natural resources, for the treatment of this pathology, without side effects and with other benefits, to assist in the glycemia control in diabetic patients, and to improve their quality of life.  相似文献   

98.
99.
Background: The perioperative use of immunomodulatory nutrition formulas in patients with head and neck cancer reduces the number of postoperative infections and the length of hospital stay. Objective: An exploratory, randomized, controlled, blind, clinical trial was designed to examine the effect of the preoperative consumption of a new, immunomodulatory, oral nutrition formula in patients with head and neck cancer. Methods: Thirty‐eight patients were randomized to receive either 400 mL/d of either the new immunomodulatory formula (IF) or that commonly used in clinical practice (CF) over 10 days prior to surgery. Thirty‐three patients completed the study. Compliance, tolerance, the length of hospital stay, the incidence of infections and noninfectious complications before discharge, and the same up to 15 and 30 days after discharge were recorded. Results: The percentage of patients who developed infections before discharge was significantly lower in the IF than in the CF group (P = .013), as was the number of infections/100 patients/d (P = .035). The length of hospital stay was significantly shorter in the IF group (P = .001). Both formulas were safe and well tolerated. No other differences were detected. These results suggest preoperative consumption of the new formula to be beneficial for patients with neck and head cancer. Further trials are needed to confirm these results and to test the efficacy of the formula in patients with other conditions. Conclusion: The new formula can be safely prescribed as part of the preoperative treatment of patients with head and neck cancer and might reduce the problem of postoperative infection.  相似文献   
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