全文获取类型
收费全文 | 854902篇 |
免费 | 70496篇 |
国内免费 | 1787篇 |
专业分类
耳鼻咽喉 | 12783篇 |
儿科学 | 24522篇 |
妇产科学 | 25040篇 |
基础医学 | 122951篇 |
口腔科学 | 25435篇 |
临床医学 | 74574篇 |
内科学 | 162196篇 |
皮肤病学 | 16945篇 |
神经病学 | 69470篇 |
特种医学 | 35123篇 |
外国民族医学 | 171篇 |
外科学 | 135599篇 |
综合类 | 24553篇 |
一般理论 | 263篇 |
预防医学 | 66226篇 |
眼科学 | 20452篇 |
药学 | 64435篇 |
中国医学 | 1577篇 |
肿瘤学 | 44870篇 |
出版年
2018年 | 7205篇 |
2015年 | 7614篇 |
2014年 | 11044篇 |
2013年 | 16709篇 |
2012年 | 22682篇 |
2011年 | 23774篇 |
2010年 | 13807篇 |
2009年 | 13002篇 |
2008年 | 22535篇 |
2007年 | 24591篇 |
2006年 | 24455篇 |
2005年 | 24108篇 |
2004年 | 23686篇 |
2003年 | 22787篇 |
2002年 | 21874篇 |
2001年 | 35763篇 |
2000年 | 36359篇 |
1999年 | 30642篇 |
1998年 | 8670篇 |
1997年 | 7892篇 |
1996年 | 7810篇 |
1995年 | 7939篇 |
1994年 | 7660篇 |
1992年 | 26615篇 |
1991年 | 26097篇 |
1990年 | 25592篇 |
1989年 | 24653篇 |
1988年 | 23199篇 |
1987年 | 22862篇 |
1986年 | 21724篇 |
1985年 | 21089篇 |
1984年 | 16353篇 |
1983年 | 13950篇 |
1982年 | 8822篇 |
1981年 | 8157篇 |
1980年 | 7625篇 |
1979年 | 16691篇 |
1978年 | 12071篇 |
1977年 | 10128篇 |
1976年 | 9265篇 |
1975年 | 10091篇 |
1974年 | 12590篇 |
1973年 | 12090篇 |
1972年 | 11507篇 |
1971年 | 10663篇 |
1970年 | 10184篇 |
1969年 | 9882篇 |
1968年 | 8887篇 |
1967年 | 8211篇 |
1966年 | 7633篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
van Bunningen R. H. Dijkstra P. U. Dieters A. van der Meer W. J. Kuijpers-Jagtman A. M. Ren Y. 《Clinical oral investigations》2022,26(2):1543-1550
Clinical Oral Investigations - To analyze differences in variation of orthodontic diagnostic measurements on lateral cephalograms reconstructed from ultra low dose-low dose (ULD-LD) cone beam... 相似文献
3.
Simone Oerlemans PhD Fabio Efficace PhD Charalampia Kyriakou PhD MD Ana Carolina Freitas PhD MD Omar Shamieh PhD MD Carien L. Creutzberg PhD MD Jens Lehmann PhD Duska Petranovic PhD MD Eva Nagele PhD Anne Bredart PhD Dong Dong PhD Christian W. Scholz PhD MD Giovanni Caocci PhD MD Stefano Molica PhD MD Laimonas Griskevicius PhD MD Aliki Xochelli PhD MD Jacobien M. Kieffer PhD Joost A. Agelink van Rentergem PhD Waleed Alrjoub BSN Anja Mueller PhD Maria Gomes Da Silva PhD MD Filipa Alves da Costa PhD PharmD Sandra Malak PhD MD Kim Cocks PhD Lonneke V. van de Poll-Franse PhD the EORTC Quality of Life Group 《Cancer》2023,129(17):2727-2740
Background
Health-related quality of life (HRQOL) is a critical aspect to consider when making treatment decisions for patients with non-Hodgkin-lymphoma (NHL). This international study by the European Organisation for Research and Treatment of Cancer (EORTC) tested the psychometric properties of two newly developed measures for patients with high-grade (HG)- and low-grade (LG)-NHL: the EORTC QLQ-NHL-HG29 and the EORTC QLQ-NHL-LG20 to supplement the core questionnaire (EORTC QLQ-C30).Methods
Overall, 768 patients with HG-NHL (N = 423) and LG-NHL (N = 345) from 12 countries completed the QLQ-C30, QLQ-NHL-HG29/QLQ-NHL-LG20 and a debriefing questionnaire at baseline, and a subset at follow-up for either retest (N = 125/124) or responsiveness to change (RCA; N = 98/49).Results
Confirmatory factor analysis showed an acceptable to good fit of the 29 items of the QLQ-NHL-HG29 on its five scales (symptom burden [SB], neuropathy, physical condition/fatigue [PF], emotional impact [EI], and worries about health/functioning [WH]), and of the 20 items of the QLQ-NHL-LG20 on its four scales (SB, PF, EI, and WH). Completion took on average 10 minutes. Test–retest reliability, convergent validity, known-group comparisons, and RCA find satisfactory results of both measures. A total of 31%–78% of patients with HG-NHL and 22%–73% of patients with LG-NHL reported symptoms and/or worries (e.g., tingling in hands/feet, lack of energy, and worries about recurrence). Patients reporting symptoms/worries had substantially lower HRQOL compared to those without.Discussion
The use of the EORTC QLQ-NHL-HG29 and QLQ-NHL-LG20 questionnaires in clinical research and practice will provide clinically relevant data to better inform treatment decision-making.Plain language summary
- The European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Group developed two questionnaires.
- These questionnaires measure health-related quality of life.
- The questionnaires are for patients with high-grade or low-grade non-Hodgkin lymphoma.
- They are called the EORTC QLQ-NHL-HG29 and QLQ-NHL-LG20.
- The questionnaires are now internationally validated.
- This study demonstrates that the questionnaires are reliably and valid, which are important aspects of a questionnaire.
- The questionnaires can now be used in clinical trials and practice.
- With the information gathered from the questionnaires, patients and clinicians can better evaluate treatments and discuss the best choice for a patient.
4.
5.
S. M. White C. L. Shelton A. W. Gelb C. Lawson F. McGain J. Muret J. D. Sherman representing the World Federation of Societies of Anaesthesiologists Global Working Group on Environmental Sustainability in Anaesthesia 《Anaesthesia》2022,77(2):201-212
The Earth’s mean surface temperature is already approximately 1.1°C higher than pre-industrial levels. Exceeding a mean 1.5°C rise by 2050 will make global adaptation to the consequences of climate change less possible. To protect public health, anaesthesia providers need to reduce the contribution their practice makes to global warming. We convened a Working Group of 45 anaesthesia providers with a recognised interest in sustainability, and used a three-stage modified Delphi consensus process to agree on principles of environmentally sustainable anaesthesia that are achievable worldwide. The Working Group agreed on the following three important underlying statements: patient safety should not be compromised by sustainable anaesthetic practices; high-, middle- and low-income countries should support each other appropriately in delivering sustainable healthcare (including anaesthesia); and healthcare systems should be mandated to reduce their contribution to global warming. We set out seven fundamental principles to guide anaesthesia providers in the move to environmentally sustainable practice, including: choice of medications and equipment; minimising waste and overuse of resources; and addressing environmental sustainability in anaesthetists’ education, research, quality improvement and local healthcare leadership activities. These changes are achievable with minimal material resource and financial investment, and should undergo re-evaluation and updates as better evidence is published. This paper discusses each principle individually, and directs readers towards further important references. 相似文献
6.
7.
8.
Juliane H. Fröhner Stephan Ripke Sarah Jurk Shu-Chen Li Tobias Banaschewski Arun L.W. Bokde Erin Burke Quinlan Sylvane Desrivières Herta Flor Antoine Grigis Hugh Garavan Andreas Heinz Rüdiger Brühl Jean-Luc Martinot Marie-Laure Paillère Martinot Eric Artiges Frauke Nees Dimitri Papadopoulos Orfanos Luise Poustka Sarah Hohmann Henrik Walter Robert Whelan Gunter Schumann Michael N. Smolka the IMAGEN Consortium 《Alcoholism, clinical and experimental research》2022,46(4):667-681
Background
While drinking alcohol, one must choose between the immediate rewarding effects and the delayed reward of a healthier lifestyle. Individuals differ in their devaluation of a delayed reward based on the time required to receive it, i.e., delay discounting (DD). Previous studies have shown that adolescents discount more steeply than adults and that steeper DD is associated with heavier alcohol use in both groups.Methods
In a large-scale longitudinal study, we investigated whether higher rates of DD are an antecedent or a consequence of alcohol use during adolescent development. As part of the IMAGEN project, 2220 adolescents completed the Monetary Choice Questionnaire as a DD measure, the Alcohol Use Disorders Identification Test, and the Timeline Follow Back interview at ages 14, 16, 18, and 22. Bivariate latent growth curve models were applied to investigate the relationship between DD and drinking. To explore the consequences of drinking, we computed the cumulative alcohol consumption and correlated it with the development of discounting. A subsample of 221 participants completed an intertemporal choice task (iTeCh) during functional magnetic resonance imaging at ages 14, 16, and 18. Repeated-measures ANOVA was used to differentiate between high-risk and low-risk drinkers on the development of neural processing during intertemporal choices.Results
Overall, high rates of DD at age 14 predicted a greater increase in drinking over 8 years. In contrast, on average, moderate alcohol use did not affect DD from ages 14 to 22. Of note, we found indicators for less brain activity in top-down control areas during intertemporal choices in the participants who drank more.Conclusions
Steep DD was shown to be a predictor rather than a consequence of alcohol use in low-level drinking adolescents. Important considerations for future longitudinal studies are the sampling strategies to be used and the reliability of the assessments.9.
Qiang Liu Zhongbiao Xu Kaixuan Zhao W. Scott Hoge Xinyuan Zhang Yingjie Mei Qiqi Lu Thoralf Niendorf Yanqiu Feng 《NMR in biomedicine》2022,35(5):e4652
The purpose of this study was to investigate the feasibility of two-dimensional (2D) navigated, interleaved multishot echo-planar imaging (EPI) to enhance kidney diffusion-weighted imaging (DWI) in rats at 7.0 T. Fully sampled interleaved four-shot EPI with 2D navigators was tailored for kidney DWI (Sprague–Dawley rats, n = 7) on a 7.0-T small bore preclinical scanner. The image quality of four-shot EPI was compared with T2-weighted rapid acquisition with relaxation enhancement (RARE) (reference) and single-shot EPI (ss-EPI) without and with parallel imaging (PI). The contrast-to-noise ratio (CNR) was examined to assess the image quality for the EPI approaches. The Dice similarity coefficient and the Hausdorff distance were used for evaluation of image distortion. Mean diffusivity (MD) and fractional anisotropy (FA) were calculated for renal cortex and medulla for all DWI approaches. The corticomedullary difference of MD and FA were assessed by Wilcoxon signed-rank test. Four-shot EPI showed the highest CNR among the three EPI variants and lowest geometric distortion versus T2-weighted RARE (mean Dice: 0.77 for ss-EPI without PI, 0.88 for ss-EPI with twofold undersampling, and 0.92 for four-shot EPI). The FA map derived from four-shot EPI clearly identified a highly anisotropic region corresponding to the inner stripe of the outer medulla. Four-shot EPI successfully discerned differences in both MD and FA between renal cortex and medulla. In conclusion, 2D navigated, interleaved multishot EPI facilitates high-quality rat kidney DWI with clearly depicted intralayer and interlayer structure and substantially reduced image distortion. This approach enables the anatomic integrity of DWI-MRI in small rodents and has the potential to benefit the characterization of renal microstructure in preclinical studies. 相似文献
10.
Devin Incerti Xiang-Ming Xu Jacquelyn W. Chou Nina Gonzaludo John W. Belmont Brock E. Schroeder 《Genetics in medicine》2022,24(1):109-118
PurposeTo estimate the cost-effectiveness of genome sequencing (GS) for diagnosing critically ill infants and noncritically ill pediatric patients (children) with suspected rare genetic diseases from a United States health sector perspective.MethodsA decision-analytic model was developed to simulate the diagnostic trajectory of patients. Parameter estimates were derived from a targeted literature review and meta-analysis. The model simulated clinical and economic outcomes associated with 3 diagnostic pathways: (1) standard diagnostic care, (2) GS, and (3) standard diagnostic care followed by GS.ResultsFor children, costs of GS ($7284) were similar to that of standard care ($7355) and lower than that of standard care followed by GS pathways ($12,030). In critically ill infants, when cost estimates were based on the length of stay in the neonatal intensive care unit, the lowest cost pathway was GS ($209,472). When only diagnostic test costs were included, the cost per diagnosis was $17,940 for standard, $17,019 for GS, and $20,255 for standard care followed by GS.ConclusionThe results of this economic model suggest that GS may be cost neutral or possibly cost saving as a first line diagnostic tool for children and critically ill infants. 相似文献