全文获取类型
收费全文 | 5686篇 |
免费 | 314篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 49篇 |
儿科学 | 317篇 |
妇产科学 | 70篇 |
基础医学 | 627篇 |
口腔科学 | 112篇 |
临床医学 | 571篇 |
内科学 | 1236篇 |
皮肤病学 | 81篇 |
神经病学 | 505篇 |
特种医学 | 146篇 |
外科学 | 1034篇 |
综合类 | 134篇 |
一般理论 | 3篇 |
预防医学 | 287篇 |
眼科学 | 148篇 |
药学 | 308篇 |
中国医学 | 15篇 |
肿瘤学 | 372篇 |
出版年
2023年 | 62篇 |
2022年 | 75篇 |
2021年 | 181篇 |
2020年 | 120篇 |
2019年 | 161篇 |
2018年 | 191篇 |
2017年 | 134篇 |
2016年 | 155篇 |
2015年 | 149篇 |
2014年 | 234篇 |
2013年 | 239篇 |
2012年 | 414篇 |
2011年 | 446篇 |
2010年 | 230篇 |
2009年 | 218篇 |
2008年 | 339篇 |
2007年 | 309篇 |
2006年 | 312篇 |
2005年 | 265篇 |
2004年 | 254篇 |
2003年 | 262篇 |
2002年 | 222篇 |
2001年 | 113篇 |
2000年 | 108篇 |
1999年 | 98篇 |
1998年 | 47篇 |
1997年 | 38篇 |
1996年 | 29篇 |
1995年 | 19篇 |
1994年 | 27篇 |
1993年 | 24篇 |
1992年 | 41篇 |
1991年 | 39篇 |
1990年 | 34篇 |
1989年 | 32篇 |
1988年 | 36篇 |
1987年 | 23篇 |
1986年 | 23篇 |
1985年 | 36篇 |
1984年 | 27篇 |
1983年 | 23篇 |
1982年 | 20篇 |
1981年 | 15篇 |
1980年 | 13篇 |
1979年 | 19篇 |
1978年 | 16篇 |
1977年 | 15篇 |
1974年 | 16篇 |
1971年 | 17篇 |
1970年 | 12篇 |
排序方式: 共有6015条查询结果,搜索用时 15 毫秒
51.
Richard W. Atkinson Dahai Yu Ben G. Armstrong Sam Pattenden Paul Wilkinson Ruth M. Doherty Mathew R. Heal H. Ross Anderson 《Environmental health perspectives》2012,120(10):1411-1417
Background: Short-term exposure to ozone has been associated with increased daily mortality. The shape of the concentration–response relationship—and, in particular, if there is a threshold—is critical for estimating public health impacts.Objective: We investigated the concentration–response relationship between daily ozone and mortality in five urban and five rural areas in the United Kingdom from 1993 to 2006.Methods: We used Poisson regression, controlling for seasonality, temperature, and influenza, to investigate associations between daily maximum 8-hr ozone and daily all-cause mortality, assuming linear, linear-threshold, and spline models for all-year and season-specific periods. We examined sensitivity to adjustment for particles (urban areas only) and alternative temperature metrics.Results: In all-year analyses, we found clear evidence for a threshold in the concentration–response relationship between ozone and all-cause mortality in London at 65 µg/m3 [95% confidence interval (CI): 58, 83] but little evidence of a threshold in other urban or rural areas. Combined linear effect estimates for all-cause mortality were comparable for urban and rural areas: 0.48% (95% CI: 0.35, 0.60) and 0.58% (95% CI: 0.36, 0.81) per 10-µg/m3 increase in ozone concentrations, respectively. Seasonal analyses suggested thresholds in both urban and rural areas for effects of ozone during summer months.Conclusions: Our results suggest that health impacts should be estimated across the whole ambient range of ozone using both threshold and nonthreshold models, and models stratified by season. Evidence of a threshold effect in London but not in other study areas requires further investigation. The public health impacts of exposure to ozone in rural areas should not be overlooked. 相似文献
52.
53.
54.
Elizabeth S. Maywood Lesley Drynan Johanna E. Chesham Mathew D. Edwards Hugues Dardente Jean-Michel Fustin David G. Hazlerigg John S. O’Neill Gemma F. Codner Nicola J. Smyllie Marco Brancaccio Michael H. Hastings 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(23):9547-9552
The suprachiasmatic nucleus (SCN) coordinates circadian rhythms that adapt the individual to solar time. SCN pacemaking revolves around feedback loops in which expression of Period (Per) and Cryptochrome (Cry) genes is periodically suppressed by their protein products. Specifically, PER/CRY complexes act at E-box sequences in Per and Cry to inhibit their transactivation by CLOCK/BMAL1 heterodimers. To function effectively, these closed intracellular loops need to be synchronized between SCN cells and to the light/dark cycle. For Per expression, this is mediated by neuropeptidergic and glutamatergic extracellular cues acting via cAMP/calcium-responsive elements (CREs) in Per genes. Cry genes, however, carry no CREs, and how CRY-dependent SCN pacemaking is synchronized remains unclear. Furthermore, whereas reporter lines are available to explore Per circadian expression in real time, no Cry equivalent exists. We therefore created a mouse, B6.Cg-Tg(Cry1-luc)01Ld, carrying a transgene (mCry1-luc) consisting of mCry1 elements containing an E-box and E′-box driving firefly luciferase. mCry1-luc organotypic SCN slices exhibited stable circadian bioluminescence rhythms with appropriate phase, period, profile, and spatial organization. In SCN lacking vasoactive intestinal peptide or its receptor, mCry1 expression was damped and desynchronized between cells. Despite the absence of CREs, mCry1-luc expression was nevertheless (indirectly) sensitive to manipulation of cAMP-dependent signaling. In mPer1/2-null SCN, mCry1-luc bioluminescence was arrhythmic and no longer suppressed by elevation of cAMP. Finally, an SCN graft procedure showed that PER-independent as well as PER-dependent mechanisms could sustain circadian expression of mCry1. The mCry1-luc mouse therefore reports circadian mCry1 expression and its interactions with vasoactive intestinal peptide, cAMP, and PER at the heart of the SCN pacemaker. 相似文献
55.
Mathew Mathews 《Journal of cross-cultural gerontology》2016,31(3):277-291
Adjustments that accompany ageing pose a challenge to the mental health of the elderly. Psychologically based counseling has been documented in Western societies as an appropriate intervention for elderly persons with depressive episodes. There is however very little research documenting how Asian elderly populations experience and benefit from counseling. This study addresses this research gap through a qualitative study based on post-counseling interviews with a sample of 41 elderly persons who received counseling at a dedicated organisation catering to the elderly in Singapore. The qualitative data revealed that clients benefitted from counseling through better emotional management – they received emotional support, found emotional healing and learnt to deal with the emotions associated with grief and loss. Clients also reported that counseling assisted them in decision making processes – older persons were able to conceive of alternatives to their predicament, obtained insights to embark on change, were enabled to take the perspective of others and found validation for their decisions. While many elderly clients greatly appreciated and benefitted from this service, citing demonstrable changes, among the very old such changes were uncommon. Cultural explanations for these differential reports and possible directions for much needed future research are provided. 相似文献
56.
The persistence of maternal vitamin D deficiency and insufficiency during pregnancy and lactation irrespective of season and supplementation 下载免费PDF全文
57.
Warren Clements Joseph Mathew Mark C. Fitzgerald Jim Koukounaras 《Journal of vascular and interventional radiology : JVIR》2021,32(4):586-592
Patients treated with splenic artery embolization (SAE) >48 hours after a blunt injury for a delayed splenic rupture (DSR) were assessed for the need for a subsequent splenectomy. Thirty-four patients underwent SAE for DSR over 10 years at our level 1 trauma center, performed at a median of 4.5 days after the injury (interquartile range = 5.5), and the patients were followed up for a median of 11 months (interquartile range = 31). There were 3 occurrences of rebleeds, and 2 patients required splenectomy (5.9%). This study showed that treatment with SAE after DSR results in splenic salvage in 94.1% of patients. 相似文献
58.
59.
Rajesh Sadanandan Arun Thankappan Bijoy Jacob Kudakachira Mathew Kuriakose 《Indian Journal of Thoracic and Cardiovascular Surgery》2012,28(2):146-147
Anomalous Left Coronary Artery from Pulmonary Artery (ALCAPA) is the commonest congenital anomaly involving coronary arteries. The combination of this anomaly with mitral regurgitation is very rare in adult population. We report the case of a 62?year old lady, who presented with breathlessness and was found to have this combined anomaly. She was treated successfully with closure of left coronary ostium from pulmonary artery and mitral valve replacement with Hancock 2 Porcine valve. To our knowledge, this is the oldest patient to have undergone successful ALCAPA repair with mitral valve replacement with bioprosthetic valve. 相似文献
60.
Andrew Ian Jenkins Mary Louise Hughes Efthymia Mantzourani Mathew Wayne Smith 《Journal of interprofessional care》2016,30(5):678-681
In recent years, the delivery of health services has seen a shift towards interprofessional teamwork in order to effectively utilise the skills of each member of the healthcare team to deliver optimal patient care. Nevertheless, a variety of barriers, including lack of communication between healthcare professionals (HCPs), have been identified. The expanding clinical services provided by community pharmacies have increased the potential for pharmacist-HCP interaction; however, primary care pharmacy environments vary from individual distinct premises to part of interprofessional ‘health centres’. As such, one potential factor affecting interprofessional communication could be the geographical location (‘space’) of HCPs. This study sought to determine whether these different primary healthcare ‘spaces’ impact on the frequency of interprofessional interactions. An anonymous, self-complete questionnaire was sent to all community pharmacies in Wales (n = 716) to quantify the frequency of interprofessional interactions between community pharmacists and other HCPs. A response rate of 62% was achieved. Results showed that pharmacists working in pharmacies physically linked to general practitioner (GP) surgeries had significantly more frequent interaction with HCPs based within the surgeries. This suggests that housing HCPs in the same physical space will enable more interprofessional interaction, supporting the drive to improve the quality of patient care. 相似文献