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   74485篇
  免费   4862篇
  国内免费   352篇
耳鼻咽喉   818篇
儿科学   1471篇
妇产科学   1115篇
基础医学   10158篇
口腔科学   1468篇
临床医学   7509篇
内科学   16678篇
皮肤病学   1448篇
神经病学   8415篇
特种医学   3452篇
外国民族医学   3篇
外科学   12499篇
综合类   440篇
一般理论   19篇
预防医学   3579篇
眼科学   1059篇
药学   4794篇
中国医学   162篇
肿瘤学   4612篇
  2023年   491篇
  2022年   646篇
  2021年   1820篇
  2020年   1089篇
  2019年   1722篇
  2018年   1975篇
  2017年   1541篇
  2016年   1809篇
  2015年   2144篇
  2014年   2737篇
  2013年   3476篇
  2012年   5506篇
  2011年   5624篇
  2010年   3412篇
  2009年   3041篇
  2008年   4942篇
  2007年   5105篇
  2006年   4733篇
  2005年   4780篇
  2004年   4335篇
  2003年   4213篇
  2002年   3861篇
  2001年   869篇
  2000年   696篇
  1999年   813篇
  1998年   853篇
  1997年   691篇
  1996年   554篇
  1995年   509篇
  1994年   449篇
  1993年   399篇
  1992年   410篇
  1991年   362篇
  1990年   293篇
  1989年   299篇
  1988年   267篇
  1987年   247篇
  1986年   260篇
  1985年   212篇
  1984年   248篇
  1983年   222篇
  1982年   201篇
  1981年   161篇
  1980年   158篇
  1979年   151篇
  1978年   110篇
  1977年   131篇
  1975年   112篇
  1974年   98篇
  1973年   112篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.

Background

Hyperglycaemia is common in patients with acute brain injury admitted to an intensive care unit (ICU). Many studies have found associations between development of hyperglycaemia and increased mortality in hospitalised patients. However, the optimal target for blood glucose control is unknown. We want to conduct a systematic review with meta-analysis and trial sequential analysis to explore the beneficial and harmful effects of restrictive versus liberal glucose control on patient outcomes in adults with severe acute brain injury.

Methods

We will systematically search medical databases including CENTRAL, Embase, MEDLINE and trial registries. We will search the following websites for ongoing or unpublished trials: http://www.controlled-trials.com/ , http://www.clinicaltrials.gov/ , www.eudraCT.com , http://centerwatch.com/ , The Cochrane Library's CENTRAL, PubMed, EMBASE, Science Citation Index Expanded and CINAHL. Two authors will independently review and select trials and extract data. We will include randomised trials comparing levels of glucose control in our analyses and observational studies will be included to address potential harms. The primary outcomes are defined as all-cause mortality, functional outcome and health-related quality of life. Secondary outcomes include serious adverse events including hypoglycaemia, length of ICU stay and duration of mechanical ventilation, and explorative outcomes including intracranial pressure and infection. Trial Sequential Analysis will be used to investigate the risk of type I error due to repetitive testing and to further explore imprecision. Quality of trials will be evaluated using the Cochrane Risk of Bias tool, and quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

Discussion

The results of the systematic review will be disseminated through peer-reviewed publication. With the review, we hope to inform future randomised clinical trials and improve clinical practice.  相似文献   
5.
European Surgery - Treatment of pilonidal sinus disease (PSD) requires a tailored approach. A national guideline was published in 2014. The current status of surgical PSD therapy...  相似文献   
6.
Despite common experiences of identity damage, decline, and deterioration, many brain injury survivors succeed in reconstructing robust identities in the wake of injury. Yet, while this accomplishment greatly benefits survivors’ quality of life, little is known about how positive identity work might be facilitated or enhanced in therapeutic institutions. Drawing on data from a women’s self-help group, we argue that an egalitarian, reflective, strength-focused, and gender-segregated environment can provide female ABI (acquired brain injury) survivors with a fertile scene for identity enhancement and offer unique opportunities for collective identity development. Sociolinguistic interactional analysis revealed four types of positive identity work undertaken within the group: constructing competent selves; tempering the threat of loss and impairment; resisting infantilisation and delegitimisation; and asserting a collective gender identity. This identity work was facilitated by specific programme attributes and activities and contributed to the global project of decentring disability and destigmatising impairments and losses. We call for increased attention to identity issues in brain injury rehabilitation and argue that gender-segregated programming can provide a unique space for female survivors to construct empowering individual and collective identities after injury.  相似文献   
7.
Aims: In neuropsychological evaluations, it is often difficult to ascertain whether poor performance on measures of validity is due to poor effort or malingering, or whether there is genuine cognitive impairment. Dunham and Denney created an algorithm to assess this question using the Medical Symptom Validity Test (MSVT). We assessed the ability of their algorithm to detect poor validity versus probable impairment, and concordance of failure on the MSVT with other freestanding tests of performance validity.

Methods: Two previously published datasets (n?=?153 and n?=?641, respectively) from outpatient neuropsychological evaluations were used to test Dunham and Denney’s algorithm, and to assess concordance of failure rates with the Test of Memory Malingering and the forced choice measure of the California Verbal Learning Test, two commonly used performance validity tests.

Results: In both datasets, none of the four cutoff scores for failure on the MSVT (70%, 75%, 80%, or 85%) identified a poor validity group with proportionally aligned failure rates on other freestanding measures of performance validity. Additionally, the protocols with probable impairment did not differ from those with poor validity on cognitive measures.

Conclusions: Despite what appeared to be a promising approach to evaluating failure on the easy MSVT subtests when clinical data are unavailable (as recommended in the advanced interpretation program, or advanced interpretation [AI], of the MSVT), the current findings indicate the AI remains the gold standard for doing so. Future research should build on this effort to address shortcomings in measures of effort in neuropsychological evaluations.  相似文献   

8.
9.
10.
ABSTRACT

Measuring hope reliably and accurately remains an important research objective, not least in less prosperous settings where ‘holding on to hope’ may be critically important in the struggle against adverse life conditions. The State Hope Scale was designed for use in the US. Despite reported application in diverse cultures and using translations the scale has not been extensively validated outside US populations. This study contributes to a larger project exploring the measurement of hope and provides a critique of Snyder’s scale as used in a Tanzanian female population of 1021 urban microfinance participants. We evaluate the scale’s validity through assessment of the empirical distribution of scores, item response profiles, internal consistency and discriminatory ability. Participants mostly scored very high and many reached very near the maximum attainable score. Hardly any endorsed the negative half of the response scale. Several problems are discussed including poor discrimination and strong evidence of acquiescence response bias. We also found little association of the scale scores with hypothesised correlates of hope. Future improvements on the measurement of hope are recommended, especially in studies outside the narrow Western context in which the scale was devised.  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