全文获取类型
收费全文 | 23079篇 |
免费 | 1742篇 |
国内免费 | 67篇 |
专业分类
耳鼻咽喉 | 301篇 |
儿科学 | 712篇 |
妇产科学 | 363篇 |
基础医学 | 2863篇 |
口腔科学 | 562篇 |
临床医学 | 2509篇 |
内科学 | 4354篇 |
皮肤病学 | 349篇 |
神经病学 | 2151篇 |
特种医学 | 761篇 |
外科学 | 3837篇 |
综合类 | 326篇 |
一般理论 | 21篇 |
预防医学 | 1999篇 |
眼科学 | 475篇 |
药学 | 1768篇 |
中国医学 | 18篇 |
肿瘤学 | 1519篇 |
出版年
2023年 | 101篇 |
2022年 | 67篇 |
2021年 | 441篇 |
2020年 | 266篇 |
2019年 | 494篇 |
2018年 | 561篇 |
2017年 | 383篇 |
2016年 | 404篇 |
2015年 | 492篇 |
2014年 | 754篇 |
2013年 | 1031篇 |
2012年 | 1616篇 |
2011年 | 1596篇 |
2010年 | 900篇 |
2009年 | 816篇 |
2008年 | 1493篇 |
2007年 | 1527篇 |
2006年 | 1566篇 |
2005年 | 1529篇 |
2004年 | 1440篇 |
2003年 | 1255篇 |
2002年 | 1164篇 |
2001年 | 310篇 |
2000年 | 315篇 |
1999年 | 313篇 |
1998年 | 252篇 |
1997年 | 171篇 |
1996年 | 144篇 |
1995年 | 162篇 |
1994年 | 152篇 |
1993年 | 139篇 |
1992年 | 181篇 |
1991年 | 192篇 |
1990年 | 177篇 |
1989年 | 173篇 |
1988年 | 171篇 |
1987年 | 160篇 |
1986年 | 141篇 |
1985年 | 135篇 |
1984年 | 141篇 |
1983年 | 125篇 |
1982年 | 101篇 |
1981年 | 108篇 |
1980年 | 91篇 |
1979年 | 107篇 |
1978年 | 102篇 |
1977年 | 70篇 |
1975年 | 76篇 |
1974年 | 78篇 |
1973年 | 85篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Girish B Nair Craig J Galban Sayf Al-Katib Robert Podolsky Maarten van den Berge Craig Stevens Edward Castillo 《The British journal of radiology》2021,94(1118)
Objective:To evaluate CT-ventilation imaging (CTVI) within a well-characterized, healthy cohort with no respiratory symptoms and examine the correlation between CTVI and concurrent pulmonary function test (PFT).Methods:CT scans and PFTs from 77 Caucasian participants in the NORM dataset (clinicaltrials.gov ) were analyzed. CTVI was generated using the robust Integrated Jacobian Formulation (IJF) method. IJF estimated total lung capacity (TLC) was computed from CTVI. Bias-adjusted Pearson’s correlation between PFT and IJF-based TLC was computed.Results:IJF- and PFT-measured TLC showed a good correlation for both males and females [males: 0.657, 95% CI (0.438–0.797); females: 0.667, 95% CI (0.416–0.817)]. When adjusting for age, height, smoking, and abnormal CT scan, correlation moderated [males: 0.432, 95% CI (0.129–0.655); females: 0.540, 95% CI (0.207–0.753)]. Visual inspection of CTVI revealed participants who had functional defects, despite the fact that all participant had normal high-resolution CT scan.Conclusion:In this study, we demonstrate that IJF computed CTVI has good correlation with concurrent PFT in a well-validated patient cohort with no respiratory symptoms.Advances in knowledge:IJF-computed CTVI’s overall numerical robustness and consistency with PFT support its potential as a method for providing spatiotemporal assessment of high and low function areas on volumetric non-contrast CT scan. NCT00848406相似文献
3.
John W Day Richard S Finkel Claudia A Chiriboga Anne M Connolly Thomas O Crawford Basil T Darras Susan T Iannaccone Nancy L Kuntz Loren D M Peña Perry B Shieh Edward C Smith Jennifer M Kwon Craig M Zaidman Meredith Schultz Douglas E Feltner Sitra Tauscher-Wisniewski Haojun Ouyang Deepa H Chand Jerry R Mendell 《Lancet neurology》2021,20(4):284-293
4.
5.
Clare Robertson Jan E. Clarkson Magaly Aceves-Martins Craig R. Ramsay Derek Richards Thibault Colloc 《International dental journal》2022,72(2):203-210
IntroductionThe coronavirus disease 2019 (COVID-19) led to the worldwide closure of dental practices or reduction of dental services. By the end of April 2020, governments and professional organisations were publishing recommendations or guidance for the reopening/restructuring of dental services. The aim of this study was to assess how dental aerosol-generating procedures (AGPs) were defined in international dental guidelines, what mitigation processes were advised, and whether they were linked to COVID-19 epidemiology.MethodsElectronic searches of a broad range of databases, along with grey literature searches, without language restriction were conducted up to 13 July 2020. Recommendations for the use of face masks and fallow times with patients without COVID-19 were assessed against the deaths per 1 million population in the included countries and country income level using Pearson Chi-squared statistics.ResultsSixty-three guidance documents were included. Most (98%) indicated that AGPs can be performed with patients without COVID-19 with caveats, including advice to restrict AGPs where possible, with 21% only recommending AGPs for dental emergencies. Face masks were recommended by most documents (94%), with 91% also specifying the use of goggles or face shields. Fallow periods for patients without COVID-19 were mentioned in 48% of documents, ranging from 2 to 180 minutes. There were no significant differences in recommendations for face masks or fallow time in patients without COVID-19 by country death rate (P = .463 and P = .901) or World Bank status (P = .504 and P = .835). Most documents recommended procedural or environmental mitigations such as preprocedural mouthwash (82%) and general ventilation (52%). Few documents provided underpinning evidence for their recommendations.ConclusionsWhile the amount of high-quality direct evidence related to dentistry and COVID-19 remains limited, it is important to be explicit about the considered judgements for recommendations as well as generate new evidence to face this challenge. 相似文献
6.
Janina Wilmskoetter Heather Bonilha Ickpyo Hong R. Jordan Hazelwood Bonnie Martin-Harris Craig Velozo 《Disability and rehabilitation》2019,41(5):549-559
AbstractPurpose: We aimed to evaluate the construct validity of the Eating Assessment Tool (EAT-10) by determining its dimensionality, rating scale integrity, item-person match, precision and relationship with the degree of airway invasion and functional oral intake.Methods: We conducted a retrospective analysis of patients’ EAT-10 scores. We used the Rasch rating scale model. We investigated correlations between the EAT-10 and scores on the Penetration-Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS).Results: The median score of the EAT-10 from 127 patients was 16 of 40 (range 0–40). Confirmatory factor analysis supported unidimensionality. The 5-point rating scale categories met published criteria. Two items misfit the Rasch model and two other items displayed differential item functioning. Rasch person reliability was 0.79. Our patient cohort was divided into three person-strata. Correlations between the EAT-10 and the PAS and FOIS were weak to moderate in strength (respectively: r?=?0.26, p?=?0.0036; r?=??0.27, p?=?0.0027).Conclusions: Our analyses identified deficits in the construct validity of the EAT-10 suggestive of a need to improve the EAT-10 to support its frequent use in clinical practice and research.
- Implications for Rehabilitation
Swallowing disorders are associated with severe complications, such as pneumonia and malnutrition, and impose both social and psychological burdens on patients.
The Eating Assessment Tool is a self-report instrument developed to estimate initial dysphagia severity and monitor change in patient-reported dysphagia symptoms as a response to treatment.
This study shows that the Eating Assessment Tool has deficits in its construct validity and a need to improve the instrument to support its frequent use in clinical practice and research.
7.
8.
Sharma Kirti Kumari Hales Tim G. Rao Vaidya Jayathirtha NicDaeid Niamh McKenzie Craig 《Forensic Toxicology》2019,37(1):1-16
Forensic Toxicology - A detailed review on the chemistry and pharmacology of non-fentanil novel synthetic opioid receptor agonists, particularly N-substituted benzamides and acetamides (known... 相似文献
9.
Yanyan Gu Benjamin G. Barwick Mala Shanmugam Craig C. Hofmeister Jonathan Kaufman Ajay Nooka Vikas Gupta Madhav Dhodapkar Lawrence H. Boise Sagar Lonial 《Blood cancer journal》2020,10(12)
Protein homeostasis is critical for maintaining eukaryotic cell function as well as responses to intrinsic and extrinsic stress. The proteasome is a major portion of the proteolytic machinery in mammalian cells and plays an important role in protein homeostasis. Multiple myeloma (MM) is a plasma cell malignancy with high production of immunoglobulins and is especially sensitive to treatments that impact protein catabolism. Therapeutic agents such as proteasome inhibitors have demonstrated significant benefit for myeloma patients in all treatment phases. Here, we demonstrate that the 11S proteasome activator PA28α is upregulated in MM cells and is key for myeloma cell growth and proliferation. PA28α also regulates MM cell sensitivity to proteasome inhibitors. Downregulation of PA28α inhibits both proteasomal load and activity, resulting in a change in protein homeostasis less dependent on the proteasome and leads to cell resistance to proteasome inhibitors. Thus, our findings suggest an important role of PA28α in MM biology, and also provides a new approach for targeting the ubiquitin-proteasome system and ultimately sensitivity to proteasome inhibitors.Subject terms: Myeloma, Translational research 相似文献
10.