全文获取类型
收费全文 | 800篇 |
免费 | 55篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 8篇 |
妇产科学 | 9篇 |
基础医学 | 60篇 |
口腔科学 | 9篇 |
临床医学 | 48篇 |
内科学 | 115篇 |
皮肤病学 | 7篇 |
神经病学 | 97篇 |
特种医学 | 46篇 |
外科学 | 227篇 |
综合类 | 1篇 |
预防医学 | 72篇 |
眼科学 | 77篇 |
药学 | 36篇 |
中国医学 | 1篇 |
肿瘤学 | 37篇 |
出版年
2023年 | 4篇 |
2022年 | 2篇 |
2021年 | 13篇 |
2020年 | 14篇 |
2019年 | 19篇 |
2018年 | 21篇 |
2017年 | 7篇 |
2016年 | 19篇 |
2015年 | 16篇 |
2014年 | 26篇 |
2013年 | 39篇 |
2012年 | 61篇 |
2011年 | 82篇 |
2010年 | 36篇 |
2009年 | 38篇 |
2008年 | 67篇 |
2007年 | 55篇 |
2006年 | 49篇 |
2005年 | 37篇 |
2004年 | 45篇 |
2003年 | 38篇 |
2002年 | 21篇 |
2001年 | 8篇 |
2000年 | 18篇 |
1999年 | 7篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1992年 | 8篇 |
1991年 | 6篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 8篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1979年 | 6篇 |
1977年 | 3篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1967年 | 3篇 |
1966年 | 2篇 |
1960年 | 5篇 |
1956年 | 2篇 |
1955年 | 2篇 |
1933年 | 2篇 |
排序方式: 共有855条查询结果,搜索用时 234 毫秒
21.
22.
Distribution of radioactivity in bone and related structures following administration of [14C]dalbavancin to New Zealand white rabbits 下载免费PDF全文
Solon EG Dowell JA Lee J King SP Damle BD 《Antimicrobial agents and chemotherapy》2007,51(8):3008-3010
Penetration of dalbavancin into noninfected bone and joint tissues was assessed after an intravenous dose of 20 mg/kg (of body weight) [(14)C]dalbavancin given to rabbits. Drug-derived radioactivity, determined over 14 days by either liquid scintillation counting or autoradiography, remained above the MIC for common gram-positive pathogens that cause bone and joint infections. 相似文献
23.
Jessie A. Elliott Vanash M. Patel Ali Kirresh Hutan Ashrafian Carel W. Le Roux Torsten Olbers Thanos Athanasiou Emmanouil Zacharakis 《Updates in surgery》2013,65(2):85-94
This study aimed to systematically evaluate the evidence-based literature on fast-track laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic adjustable gastric banding (LAGB) to determine the feasibility and safety of fast-track laparoscopic bariatric surgery. A literature search of PubMed, EMBASE and Cochrane Library using the MeSH terms “bariatric surgery”, “ambulatory surgical procedures” and related terms as keywords was performed. The study included articles that reported on intended next-day discharge for LRYGB and same-day discharge for LAGB. Data were extracted on study design and size, patient demographics, patient-selection criteria, patient preparation, perioperative management, operative details, clinical outcomes, and follow-up. The review included 13 studies classified as level 3b or 4 evidence. There were seven studies that investigated LAGB, five studies investigated LRYGB and one study detailed outcomes from both LRYGB and LAGB. Next-day discharge rate ranged from 81 to 100 % for LRYGB. Same-day discharge rate ranged from 76 to 98 % for LAGB. In LRYGB and LAGB complication, re-admission and mortality rates (≤10.5, ≤7.5, ≤0.1 %, respectively) were comparable with the conventional perioperative care. From our results, the fast-track management of patients undergoing LRYGB and LAGB is feasible. With careful patient selection and preparation within high-volume centres, and application of care pathways including close outpatient follow-up, outcomes for fast-track bariatric procedures can compare favourably with those reported in the literature for standard management, but with decreased cost. However, further studies from independent researchers are required to determine the safety of a generalised adoption of this approach outside of dedicated bariatric units, and to formally demonstrate the cost-benefit of fast-track bariatric surgery. 相似文献
24.
Anagnostopoulos I. Lagou S. Spanorriga M. K. Tavernaraki K. Poulakou G. Syrigos K. N. Thanos L. 《Journal of thrombosis and thrombolysis》2020,49(4):572-577
Journal of Thrombosis and Thrombolysis - Our knowledge about the incidence of pulmonary embolism (PE) and the performance of age adjusted D-dimers (Dd) cutoff amongst patients with lung cancer (LC)... 相似文献
25.
Coronary artery bypass graft surgery remains the main treatment modality for multivessel coronary artery disease and has consistently been demonstrated to have significantly lower rates of major adverse cardiac and cerebrovascular events in comparison to percutaneous coronary intervention. In this article we will explore the advances over time and the recent refinements in the techniques of surgical revascularization and how these contribute to the superior outcome profile associated with coronary artery bypass graft surgery. These include the current outcome status of coronary artery bypass grafting; the major landmark trials, registries and meta-analyses comparing coronary artery bypass grafting and percutaneous coronary intervention; the developments in coronary artery disease lesion classification; the techniques for the physiological assessment of coronary artery lesions; bypass grafting using arterial conduits; the role of off-pump coronary artery surgery; the outcomes of reoperative surgery; hybrid techniques for coronary revascularization; minimally invasive coronary artery surgery and finally robotic surgery. 相似文献
26.
The global epidemic of obesity and the worldwide prevalence of obstructive sleep apnoea (OSA) are both increasing. Epidemiological studies reveal an association between obesity, weight gain and OSA. Metabolic or bariatric operations provide sustained weight loss and resolve or improve the symptoms of OSA in the majority of morbidly obese individuals. These operations also modulate the metabolic profile to improve glycaemic control, to decrease cardiovascular risk and obesity-related mortality. The beneficial effects of metabolic operations on OSA include mechanical weight-dependent and metabolic weight-independent effects that are achieved through the BRAVE effects: (Bile flow alteration; Reduction of gastric size; Anatomical gut rearrangement and altered flow of nutrients; Vagal manipulation; and Enteric gut hormone modulation). These result in an improvement in insulin resistance, adipokines, cytokines and systemic inflammation. A literature analysis was performed with statistical pooling of available surgical and medical studies to determine whether the weighted mean decrease in body mass index and sleep apnoea severity (measured by the apnoea-hypopnoea index) are larger in metabolic surgical studies than in non-surgical weight loss studies (diet, exercise and medication). However, heterogeneity across available trials, poor follow-up measures and a deficiency in comparative studies between surgical and non-surgical therapy precludes definitive statements regarding the relative benefits of surgical therapy. Further research is required to quantify robustly the effects and mechanisms of sleep apnoea resolution by metabolic surgery, which may reveal novel non-surgical treatments or enhanced surgical strategies in the management of this multisystem sleep disorder. 相似文献
27.
ObjectivesThe aims of this study is firstly to analyse the impact of prehospital time related variables on mortality, in a specific subset of HEMS patients and secondly to demonstrate any interactions between time related variables and factors taking place in the prehospital setting.MethodsRetrospective analysis of 688 consecutive London HEMS transfers with severe thoracic trauma and mean injury severity score (ISS) of 35, during a 9-year period (1994–2002). We have analysed the effect of the following time related variables on mortality: activation time, arrival on scene time (AoS), stay on scene time (SoS), total time (ToT), rush-hour time (RhT) and leisure-hour time (LhT). We have also investigated the interaction of the above mentioned variables with observations and interventions taken place on scene and at accident and emergency department (A&;E) following adjustment for type and severity of injury. For statistical analysis the time variables were grouped into quintiles.ResultsSix hundred eighty eight victims (510 males) with mean age of 38.5 ± 17.5 had total survival rate of 59.6%. The mean AoS and SoS were 11.6 ± 5.8 min and 36.6 ± 16.8 min, respectively. ToT > 65 min, as in quintiles III, IV and V with mean ToT of 65.3 min, 74.9 min and 102.7 min respectively, had an influence on mortality with calculated adjusted OR of 1.37 (95%CI = 0.47–3.94), 3.36 (95%CI = 1.22–9.23) and 1.43 (95%CI = 0.52–3.92) respectively with concomitant adjustment for type of injury, severity of injury, age, physiological variables on scene and on scene emergency thoracotomy (ET). ET on scene was an independent predictor for mortality (OR 3.94, 95%CI = 1.03–15.06). SoS of more than 34 min can lead to harmful changes on patients’ pathophysiological status. ISS has no significant effect on AoS or SoS. RhT and LhT have no significant effect on mortality and they did not influence the AoS and SoS.ConclusionThis study suggests that time related variables have a complex and heterogeneous effect on mortality. Thoracic trauma victims usually have high ISS, in such population, ToT <65 min may be associated with lower possibility of death. Neither AoS nor SoS was influenced by time of incident or severity of injury. 相似文献
28.
Pinto A Manson H Pauly B Thanos J Parks A Cox A 《International journal for equity in health》2012,11(1):28
ABSTRACT: INTRODUCTION: Promoting health equity is a key goal of many public health systems. However, little isknown about how equity is conceptualized in such systems, particularly as standards ofpractice are established. As part of a larger study examining the renewal of public health intwo Canadian provinces, Ontario and British Columbia (BC), we undertook an analysis ofrelevant public health documents related to equity. The aim of this paper is to discuss howequity is considered within documents that outline standards for public health. METHODS: A research team consisting of policymakers and academics identified key documents relatedto the public health renewal process in each province. The documents were analyzed usingconstant comparative analysis to identify key themes related to the conceptualization andintegration of health equity as part of public health renewal in Ontario and BC. Documentswere coded inductively with higher levels of abstraction achieved through multiple readings.Sets of questions were developed to guide the analysis throughout the process. RESULTS: In both sets of provincial documents health inequities were defined in a similar fashion, as theconsequence of unfair or unjust structural conditions. Reducing health inequities was anexplicit goal of the public health renewal process. In Ontario, addressing "prioritypopulations" was used as a proxy term for health equity and the focus was on existingprograms. In BC, the incorporation of an equity lens enhanced the identification of healthinequities, with a particular emphasis on the social determinants of health. In both, prioritywas given to reducing barriers to public health services and to forming partnerships withother sectors to reduce health inequities. Limits to the accountability of public health toreduce health inequities were identified in both provinces. CONCLUSION: This study contributes to understanding how health equity is conceptualized and incorporatedinto standards for local public health. As reflected in their policies, both provinces haveembraced the importance of reducing health inequities. Both conceptualized this as rooted instructural injustices and the social determinants of health. Differences in theconceptualization of health equity likely reflect contextual influences on the public healthrenewal processes in each jurisdiction. 相似文献
29.
Wang GJ Volkow ND Franceschi D Fowler JS Thanos PK Scherbaum N Pappas N Wong CT Hitzemann RJ Felder CA 《Alcoholism, clinical and experimental research》2000,24(6):822-829
BACKGROUND: Ethanol has a broad range of actions on many neurotransmitter systems. The depressant actions of ethanol in the brain are related in part to facilitation of gamma-aminobutyric acid (GABA) neurotransmission via its interaction with the benzodiazepine/GABA receptor complex. The purpose of this study was to evaluate the effects of ethanol on regional brain metabolism in 10 healthy right-handed men. The results were compared with those we previously published in a different group of 16 normal male subjects who received intravenous lorazepam, a benzodiazepine drug that also enhances GABA neurotransmission. METHODS: The subjects were scanned with positron emission tomography and [F-18] fluorodeoxyglucose twice: 40 min after the end of placebo (diet soda) or ethanol (0.75 g/kg) oral administration. Image data sets were analyzed by using both the region of interest and the statistical parametric mapping (SPM) approach. SPM was used to generate a difference image between baseline and ethanol, which we compared to the difference image between baseline and lorazepam (30 microg/kg). RESULTS: Ethanol significantly increased self-reports of "high" (p < or = 0.0001), dizziness (p < or = 0.004), and intoxication (p < or = 0.0001). Ethanol significantly decreased whole brain (-25 +/- 6%, p < or = 0.0001) and regional metabolism. Normalization of the regional measures by whole brain metabolism (relative measures) showed that ethanol decreased relative metabolic activity in occipital cortex (-4.9 +/- 4.1%, p < or = 0.006), whereas it increased relative metabolic act in left temporal cortex (+3.5 +/- 2.9%, p < or = 0.006) and left basal ganglia (+9 +/- 6.3%, p < or = 0.0009). SPM analyses revealed the same pattern of responses as the relative measures, showing decreases in occipital cortex and increases in left temporal cortex. Comparison of the relative measures and the SPM analyses obtained with lorazepam data revealed a similar pattern of effects, with relative decreases in occipital cortex (-7.8 +/- 4.8%) and relative increases in left temporal cortex (+3.8 +/- 5.7%). Lorazepam, but not ethanol, also decreased thalamic metabolism (-11.2 +/- 7.2%). CONCLUSIONS: These results support similar though not identical mechanisms for the effects of alcohol and benzodiazepines on brain glucose metabolism. The fact that lorazepam, but not alcohol, reduced thalamic metabolism, an effect associated with sleepiness, could explain the higher sedative effects of lorazepam than of alcohol. 相似文献
30.
Kumar P Athanasiou T Ali A Nair S Oz BS DeSouza A Moat N Shore DF Pepper JR 《The Journal of heart valve disease》2004,13(6):904-12; discussion 912-3
BACKGROUND AND AIM OF THE STUDY: Late reoperation for failed aortic homograft is widely regarded as a high-risk procedure. A review is presented of the authors' experience of redo-aortic valve replacement (re-do AVR) examining factors which affect, and whether a previous aortic homograft replacement influences, operative outcome. METHODS: A retrospective review was conducted of consecutive re-do AVR performed at the authors' institution between 1998 and 2002. RESULTS: During the study period, 178 patients (125 males, 53 females; mean age 52.4 years; range: 16-85 years) underwent re-do AVR. The group included first-time (72%), second-time (20%), and more than third-time re-do AVR (8%). Forty-six patients (26%) received a homograft (group I), and 132 (74%) a stented biological/mechanical valve (group II). The two groups were matched for baseline clinical characteristics and operative variables. The type of explanted valve, and preoperative and operative variables, were analyzed using univariate and multivariate models. Primary outcome was defined as 30-day mortality, and secondary outcome as postoperative complications. The overall 30-day mortality was 12.3%, but was much lower (4.5%) for elective isolated and multiple re-do AVR. Univariate analysis showed significant predictors of 30-day mortality to be: age >65 years (p = 0.02); renal dysfunction (p = 0.005); preoperative unstable status (p = 0.03); preoperative NYHA class III/IV dyspnea (p = 0.02); non-elective operation (p = 0.01); preoperative arrhythmia (p = 0.005); history of chronic obstructive pulmonary disease (COPD) (p = 0.002); preoperative cardiogenic shock (p = 0.03); impaired left ventricular ejection fraction (LVEF) <50% (p = 0.04); and other valvular procedure(s) performed simultaneously (p = 0.01). In a multivariate analysis, the only significant predictors of 30-day mortality were impaired LVEF (p = 0.03) and a history of COPD (p = 0.007). Group I patients had a significantly shorter mean hospital stay (10.2+/-5.9 versus 14.1+/-12.5 days; p = 0.009), but there were no significant differences between groups in terms of postoperative complications. CONCLUSION: A previous aortic homograft replacement was not associated with an increased operative risk at the time of re-do AVR. A history was COPD was an important predictor of 30-day mortality, and this finding requires further investigation. 相似文献