全文获取类型
收费全文 | 2282篇 |
免费 | 33篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 13篇 |
妇产科学 | 49篇 |
基础医学 | 144篇 |
口腔科学 | 41篇 |
临床医学 | 127篇 |
内科学 | 995篇 |
皮肤病学 | 30篇 |
神经病学 | 203篇 |
特种医学 | 25篇 |
外科学 | 407篇 |
综合类 | 41篇 |
预防医学 | 105篇 |
眼科学 | 9篇 |
药学 | 96篇 |
中国医学 | 1篇 |
肿瘤学 | 24篇 |
出版年
2023年 | 38篇 |
2022年 | 44篇 |
2021年 | 71篇 |
2020年 | 42篇 |
2019年 | 146篇 |
2018年 | 132篇 |
2017年 | 67篇 |
2016年 | 27篇 |
2015年 | 33篇 |
2014年 | 83篇 |
2013年 | 77篇 |
2012年 | 16篇 |
2011年 | 44篇 |
2010年 | 23篇 |
2009年 | 32篇 |
2008年 | 39篇 |
2007年 | 34篇 |
2006年 | 12篇 |
2005年 | 14篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 2篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1990年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 52篇 |
1984年 | 128篇 |
1983年 | 150篇 |
1982年 | 117篇 |
1981年 | 117篇 |
1980年 | 117篇 |
1979年 | 117篇 |
1978年 | 118篇 |
1977年 | 55篇 |
1976年 | 103篇 |
1975年 | 75篇 |
1974年 | 93篇 |
1973年 | 65篇 |
排序方式: 共有2315条查询结果,搜索用时 15 毫秒
1.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):149-158.e4
BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization. 相似文献
2.
The harsh treatment of former prisoners of war (POWs) of World War II and the Korean conflict resulted in severe malnutrition. Although rarely linked to specific long-term medical problems, a specific marker of malnutrition, self-reported lower limb edema (presumably due to a vitamin B deficiency) was associated with a three-fold increase in subsequent death attributed to ischemic heart disease (IHD) during the follow-up period from 1967 through 1975. Although there is at present no medical basis for linking edema, which is perhaps a marker for some unmeasured risk factor, to subsequent IHD, this finding may nonetheless have medical implications for the group of former POWs and other populations with severe dietary deficiency. It also suggests there may be a need to reexamine currently held theories on malnutrition and subsequent chronic disease. 相似文献
3.
Trichosporon is a common cause of superficial mycotic infection but has rarely been associated with endocarditis. The case of a patient who had a peritoneovenous shunt for chronic intractable ascites due to Laennec liver cirrhosis is described. The shunt was revised on several occasions, and the last procedure was complicated by a draining skin sinus wound. To the authors' knowledge, this is the first reported case of Trichosporon endocarditis complicating a peritoneovenous shunt. 相似文献
4.
Kristin M. Mattocks A. Rani Elwy Elizabeth M. Yano Justin Giovannelli Michael Adelberg Michelle A. Mengeling Kristin J. Cunningham Kameron L. Matthews 《Health services research》2021,56(3):400
ObjectivesTo inform how the VA should develop and implement network adequacy standards, we convened an expert panel to discuss Community Care Network (CCN) adequacy and how VA might implement network adequacy standards for community care.Data Sources/Study settingData were generated from expert panel ratings and from an audio‐recorded expert panel meeting conducted in Arlington, Virginia, in October 2017.Study DesignWe used a modified Delphi panel process involving one round of expert panel ratings provided by nine experts in network adequacy standards. Expert panel members received a list of network adequacy standard measures used in commercial and government market and were provided a rating form listing a total of 11 measures and characteristics to rate.Data Collection MethodsItems on the rating form were individually discussed during an expert panel meeting between the nine expert panel members and VA Office of Community Care leaders. Attendees addressed discordant views and generated revised or new standards accordingly. Recorded audio data were transcribed to facilitate thematic analysis regarding opportunities and challenges with implementing network adequacy standards in VA Community Care.Principal FindingsThe five highest ranked standards were network directories for Veterans, regular reporting of network adequacy data to VA, maximum wait time/distance standards, minimum ratio of providers to enrolled population, and qualitative assessments of network adequacy. During the expert panel discussion with VA Community Care leaders, opportunities and challenges implementing network adequacy standards were highlighted.ConclusionsOur expert panel shed light on priorities for network adequacy to be implemented under CCN contracts, such as developing comprehensive provider directories for Veterans to use when selecting community providers. Remaining questions focus on whether the VA could reasonably develop and implement network adequacy standards given current Congressional restraints on VA reimbursement to community providers. 相似文献
5.
Kali S. Thomas Emily Corneau Courtney H. Van Houtven Portia Cornell David Aron David M. Dosa Susan M. Allen 《Health services research》2021,56(3):389
ObjectiveTo examine characteristics that are associated with receipt of Aid and Attendance (A&A), an enhanced pension benefit for Veterans who qualify on the basis of needing daily assistance, among Veterans who receive pensions.Data sourcesSecondary data analysis of 2016‐2017 national VA administrative data linked with Medicare claims.Study designObservational study examining sociodemographic, medical, and healthcare utilization characteristics associated with receipt of A&A among Veterans receiving pension.Principal findingsIn 2017, 9.7% of Veterans with pension newly received the A&A benefit. The probability of receiving A&A among black and Hispanic pensioners was 4.6 percentage points lower than for white pensioners (95%CI = −0.051, −0.042). Married Veterans receiving pension had a 4.4‐percentage point higher probability of receiving A&A (95%CI = 0.039, 0.048). Most indicators of need for assistance (eg, home health utilization, dementia, stroke) were associated with significantly higher probabilities of receiving A&A, with notable exceptions: pensioners with a diagnosis of Post‐Traumatic Stress Disorder (marginal effect = −0.029 95%CI = −0.037, −0.021) or enrolled in Medicaid (marginal effect = −0.053, 95%CI = −0.057, −0.050) had lower probabilities of receiving A&A. Unadjusted and adjusted rates of receiving A&A among Veterans receiving pension varied by VA medical center.ConclusionsThis study identified potential inequities in receipt of the A&A enhanced pension among a sample of Veterans receiving pension. Increased Veteran outreach, provider education, and VA office coordination can potentially reduce inequities in access to this benefit. 相似文献
6.
《Vaccine》2022,40(35):5141-5152
BackgroundAchieving high COVID-19 vaccination rates among employees is necessary to prevent outbreaks in health care settings. The goal of the study was to produce actionable and timely evidence about factors underlying the intention and decisions to obtain the COVID-19 vaccine by employees.MethodsThe study was conducted from December 2020 – May 2021 with employees from a VA health care system in Southeastern US. The study used a convergent mixed methods design comprising two main activities: a cross-sectional survey conducted prior to COVID-19 vaccine distribution, and semi-structured interviews conducted 4–6 months after vaccine distribution. Data were collected about participant characteristics, vaccination intention prior to distribution, vaccination decision post-distribution, determinants of vaccination intention and decision, activating factors, sources of information and intervention needs. Data from the survey and interviews were analyzed separately and integrated narratively in the discussion.ResultsPrior to vaccine distribution, 77% of employees wanted to be vaccinated. Post vaccine distribution, we identified 5 distinct decision-making groups: 1) vaccine believers who actively sought vaccination and included those sometimes described as “immunization advocates”, 2) go along to get along (GATGA) individuals who got vaccinated but did not actively seek it, 3) cautious acceptors who got the COVID-19 vaccine after some delay, 4) fence sitters who remained uncertain about getting vaccinated, and 5) vaccine refusers who actively rejected the COVID-19 vaccine. Participants identifying with Black or multiple races were more likely to express hesitancy in their vaccination intention.ConclusionThe findings of our study highlight distinct decision-making profiles associated with COVID-19 vaccination among employees of a VA health care system, and provide tailored recommendations to reduce vaccine hesitancy in this population. 相似文献
7.
8.
Alpha1-acid glycoprotein (alpha1-AG) was purified from human sera, and its binding properties with respect to psychotropic drugs were examined by equilibrium dialysis methods in order to clarify the specificity of binding. Radioactive imipramine, a tricyclic antidepressant, was used as the primary ligand. Other drugs, representative of different classes, were tested as potential inhibitors of the alpha1-AG-imipramine binding. The K(a) for imipramine was 2.8 x 10(5) (+/- 0.8) M(-10 (mean +/- S.D.). Chlorpromazine, fluphenazine, thioridazine, loxapine and thiothixene, which are antipsychotic drugs, were competitive inhibitors of imipramine binding, and their K(a) values were in the same range. Propranolol, haloperidol and diazepam were also competitive inhibitors but their affinities were lower. Molindone, an indolic antipsychotic, when tested at the same concentrations as the other drugs, did not affect imipramine binding. Trihexyphenidyl, an anti-Parkinson drug, was a potent but noncompetitive inhibitor. These data identify the antidepressant and major tranquilizer drugs that exhibit high affinity for alpha1-AG and indicate that alpha1-AG may account for 40 per cent of total imipramine bound in serum. Since in psychiatric clinical practice two drugs are frequently administered together, possible competitive effects are discussed as well as the potential role of alpha1-AG in psychiatric illness. 相似文献
9.
10.
Bella Etingen Laura D. Carbone Marylou Guihan Cara Ray Hamad Aslam Rachel Elam Frances M. Weaver 《The journal of spinal cord medicine》2022,45(6):946
Context/ObjectiveTo describe patient experiences with fracture prevention and management among persons with spinal cord injuries/disorders (SCI/D).DesignQualitative data collected via semi-structured telephone interviews.SettingVeterans Health Administration (VA) SCI/D System of Care.ParticipantsVeterans with SCI/D (n = 32) who had experienced at least one lower-extremity fracture in the prior 18 months.InterventionsN/A.Outcome MeasuresInterview questions addressed patients’: pre-fracture knowledge of osteoporosis and bone health, diagnosis and management of osteoporosis, history and experiences with fracture treatment, and post-fracture care and experiences.ResultsParticipants expressed concerns about bone health and fractures in particular, which for some, limited activities and participation. Participants recalled receiving little information from providers about bone health or osteoporosis and described little knowledge about osteoporosis prevention prior to their fracture. Few participants reported medication management for osteoporosis, however many reported receiving radiographs/scans to confirm a fracture and most reported being managed non-operatively. Some reported preference for surgical treatment and believed their outcomes would have been better had their fracture been managed differently. Many reported not feeling fully included in treatment decision-making. Some described decreased function, independence and/or participation post-fracture.Conclusion(s)Our results indicate that persons with SCI/D report lacking substantive knowledge about bone health and/or fracture prevention, and following fracture, feel unable and/or hesitant to resume pre-fracture participation. In addition, our findings indicate that individuals with SCI/D may not feel as engaged as they would like to be in establishing fracture treatment plans. As such, persons with SCI/D may benefit from ongoing discussions with providers about risks and benefits of fracture treatment options and consideration of subsequent function and participation, to ensure patients preferences are considered. 相似文献