全文获取类型
收费全文 | 1842322篇 |
免费 | 126252篇 |
国内免费 | 3835篇 |
专业分类
耳鼻咽喉 | 26156篇 |
儿科学 | 54093篇 |
妇产科学 | 49328篇 |
基础医学 | 259525篇 |
口腔科学 | 56318篇 |
临床医学 | 155315篇 |
内科学 | 368416篇 |
皮肤病学 | 39356篇 |
神经病学 | 144947篇 |
特种医学 | 72059篇 |
外国民族医学 | 435篇 |
外科学 | 290134篇 |
综合类 | 35876篇 |
现状与发展 | 2篇 |
一般理论 | 524篇 |
预防医学 | 133413篇 |
眼科学 | 41659篇 |
药学 | 135302篇 |
3篇 | |
中国医学 | 4208篇 |
肿瘤学 | 105340篇 |
出版年
2019年 | 14196篇 |
2018年 | 20514篇 |
2017年 | 15892篇 |
2016年 | 16912篇 |
2015年 | 19366篇 |
2014年 | 27019篇 |
2013年 | 39631篇 |
2012年 | 54663篇 |
2011年 | 57551篇 |
2010年 | 33773篇 |
2009年 | 32023篇 |
2008年 | 54131篇 |
2007年 | 57060篇 |
2006年 | 57296篇 |
2005年 | 56154篇 |
2004年 | 53965篇 |
2003年 | 51776篇 |
2002年 | 49403篇 |
2001年 | 91386篇 |
2000年 | 94149篇 |
1999年 | 79381篇 |
1998年 | 20483篇 |
1997年 | 18317篇 |
1996年 | 18269篇 |
1995年 | 16956篇 |
1994年 | 16036篇 |
1993年 | 14899篇 |
1992年 | 60777篇 |
1991年 | 58276篇 |
1990年 | 56547篇 |
1989年 | 54924篇 |
1988年 | 50360篇 |
1987年 | 49362篇 |
1986年 | 46587篇 |
1985年 | 44464篇 |
1984年 | 32370篇 |
1983年 | 27481篇 |
1982年 | 15317篇 |
1979年 | 29254篇 |
1978年 | 20033篇 |
1977年 | 17060篇 |
1976年 | 15422篇 |
1975年 | 17083篇 |
1974年 | 20510篇 |
1973年 | 19436篇 |
1972年 | 18454篇 |
1971年 | 17232篇 |
1970年 | 16627篇 |
1969年 | 15557篇 |
1968年 | 14513篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
A. D. Kane J. Soar R. A. Armstrong E. Kursumovic M. T. Davies F. C. Oglesby L. Cortes C. Taylor I. K. Moppett S. Agarwal J. Cordingley J. Dorey S. J. Finney G. Kunst D. N. Lucas G. Nickols R. Mouton J. P. Nolan B. Patel V. J. Pappachan F. Plaat B. R. Scholefield J. H. Smith L. Varney T. M. Cook collaborators 《Anaesthesia》2023,78(6):701-711
Detailed contemporary knowledge of the characteristics of the surgical population, national anaesthetic workload, anaesthetic techniques and behaviours are essential to monitor productivity, inform policy and direct research themes. Every 3–4 years, the Royal College of Anaesthetists, as part of its National Audit Projects (NAP), performs a snapshot activity survey in all UK hospitals delivering anaesthesia, collecting patient-level encounter data from all cases under the care of an anaesthetist. During November 2021, as part of NAP7, anaesthetists recorded details of all cases undertaken over 4 days at their site through an online survey capturing anonymous patient characteristics and anaesthetic details. Of 416 hospital sites invited to participate, 352 (85%) completed the activity survey. From these, 24,177 reports were returned, of which 24,172 (99%) were included in the final dataset. The work patterns by day of the week, time of day and surgical specialty were similar to previous NAP activity surveys. However, in non-obstetric patients, between NAP5 (2013) and NAP7 (2021) activity surveys, the estimated median age of patients increased by 2.3 years from median (IQR) of 50.5 (28.4–69.1) to 52.8 (32.1–69.2) years. The median (IQR) BMI increased from 24.9 (21.5–29.5) to 26.7 (22.3–31.7) kg.m–2. The proportion of patients who scored as ASA physical status 1 decreased from 37% in NAP5 to 24% in NAP7. The use of total intravenous anaesthesia increased from 8% of general anaesthesia cases to 26% between NAP5 and NAP7. Some changes may reflect the impact of the COVID-19 pandemic on the anaesthetic population, though patients with confirmed COVID-19 accounted for only 149 (1%) cases. These data show a rising burden of age, obesity and comorbidity in patients requiring anaesthesia care, likely to impact UK peri-operative services significantly. 相似文献
3.
M.S. Iqbal G. Vashisht R. McMenemin P. Atherton F. McDonald T. Simmons A. Bradshaw J. Kovarik H. Turnbull L. Dodd P. Mulvenna A. Greystoke 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(2):e1-e10
Aims
Concomitant chemoradiation is the standard of care in patients with inoperable non-small cell lung cancer. The purpose of this study was to analyse the survival outcome and toxicity data of using hypofractionated chemoradiation.Materials and methods
One hundred patients were treated from June 2011 to November 2016. Treatment consisted of 55 Gy in 20 daily fractions concurrently with split-dose cisplatin vinorelbine chemotherapy over 4 weeks followed by two cycles of cisplatin vinorelbine only. Survival was estimated using Kaplan–Meier and Cox regression was carried out for known prognostic factors. A systematic search of literature was conducted using Medline, Embase and Cochrane databases and relevant references included.Results
In total, 97% of patients completed radiotherapy and 73% of patients completed all four cycles of chemotherapy. One patient died of a cardiac event during consolidative chemotherapy. There were two cases of grade 4 toxicities (one sepsis, one renal impairment). Grade 3 toxicities included nausea/vomiting (17%), oesophagitis (15%), infection with neutropenia (12%) and pneumonitis (4%). Clinical benefit was seen in 86%. Two-year progression-free survival and overall survival rates were 49% and 58%, respectively. The median progression-free survival and overall survival were 23.4 and 43.4 months, respectively. The only significant prognostic factor was the number of chemotherapy cycles received (P = 0.02). The systematic review identified 13 relevant studies; a variety of regimens were assessed with variable reporting of outcomes and toxicity but with overall an improvement in survival over time.Conclusion
Our experience compared with the original phase II trial showed improved treatment completion rates and survival with acceptable morbidity. With appropriate patient selection this regimen is an effective treatment option for locally advanced non-small cell lung cancer. This study helps to benchmark efficacy and toxicity rates while considering the addition of new agents to hypofractionated concurrent chemoradiotherapy. The agreement of a standard regimen for assessment in future trials would be beneficial. 相似文献4.
T. Steinmeier S. Schulze Schleithoff B. Timmermann 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(3):142-150
Aims
Childhood cancer is rare and survival of childhood cancer has increased up to 80% at 5 years after diagnosis. Radiotherapy is an important element of the multimodal treatment concept. However, due to growing tissue, children are particularly sensitive to radiation-related side-effects and the induction of secondary malignancies. However, radiotherapy techniques have continuously progressed. In addition, modern treatment concepts have been improved in order to minimise long-term effects. Today, radiotherapy is used for various tumour types in childhood, such as sarcomas and tumours of the central nervous system.Materials and methods
External beam therapy with either photons or protons and brachytherapy are predominantly used for the treatment of childhood tumours. Technical developments and features, as well as clinical outcomes, for several tumour entities are presented.Results
The development of radiotherapy techniques, as well as risk-adapted therapy concepts, resulted in promising outcome regarding tumour control, survival and therapy-related side-effects. It is assumed that proton therapy will be increasingly used for treating children in the future. However, more data have to be collected through multi-institutional registries in order to strengthen the evidence.Conclusion
The development of radiotherapy techniques is beneficial for children in terms of reducing dose exposure. As compared with other modern and highly conformal techniques, particularly proton therapy may achieve high survival rates and tumour control rates while decreasing the risk for side-effects. However, clinical evidence for modern radiotherapy techniques is still limited today. An optimal patient triaging with the selection of the most appropriate radiation technique for each individual patient will be an important goal for the future. 相似文献5.
Milan Milojevic Patrick W. Serruys Joseph F. Sabik David E. Kandzari Erick Schampaert Ad J. van Boven Ferenc Horkay Imre Ungi Samer Mansour Adrian P. Banning David P. Taggart Manel Sabaté Anthony H. Gershlick Andrzej Bochenek Jose Pomar Nicholas J. Lembo Nicolas Noiseux John D. Puskas Arie Pieter Kappetein 《Journal of the American College of Cardiology》2019,73(13):1616-1628
Background
The randomized EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial reported a similar rate of the 3-year composite primary endpoint of death, myocardial infarction (MI), or stroke in patients with left main coronary artery disease (LMCAD) and site-assessed low or intermediate SYNTAX scores treated with percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). Whether these results are consistent in high-risk patients with diabetes, who have fared relatively better with CABG in most prior trials, is unknown.Objectives
In this pre-specified subgroup analysis from the EXCEL trial, the authors sought to examine the effect of diabetes in patients with LMCAD treated with PCI versus CABG.Methods
Patients (N = 1,905) with LMCAD and site-assessed low or intermediate CAD complexity (SYNTAX scores ≤32) were randomized 1:1 to PCI with everolimus-eluting stents versus CABG, stratified by the presence of diabetes. The primary endpoint was the rate of a composite of all-cause death, stroke, or MI at 3 years. Outcomes were examined in patients with (n = 554) and without (n = 1,350) diabetes.Results
The 3-year composite primary endpoint was significantly higher in diabetic compared with nondiabetic patients (20.0% vs. 12.9%; p < 0.001). The rate of the 3-year primary endpoint was similar after treatment with PCI and CABG in diabetic patients (20.7% vs. 19.3%, respectively; hazard ratio: 1.03; 95% confidence interval: 0.71 to 1.50; p = 0.87) and nondiabetic patients (12.9% vs. 12.9%, respectively; hazard ratio: 0.98; 95% confidence interval: 0.73 to 1.32; p = 0.89). All-cause death at 3 years occurred in 13.6% of PCI and 9.0% of CABG patients (p = 0.046), although no significant interaction was present between diabetes status and treatment for all-cause death (p = 0.22) or other endpoints, including the 3-year primary endpoint (p = 0.82) or the major secondary endpoints of death, MI, or stroke at 30 days (p = 0.61) or death, MI, stroke, or ischemia-driven revascularization at 3 years (p = 0.65).Conclusions
In the EXCEL trial, the relative 30-day and 3-year outcomes of PCI with everolimus-eluting stents versus CABG were consistent in diabetic and nondiabetic patients with LMCAD and site-assessed low or intermediate SYNTAX scores.(Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776) 相似文献6.
N. Shor R. Deschamps A. Cobo Calvo E. Maillart H. Zephir J. Ciron C. Papeix F. Durand-Dubief A. Ruet X. Ayrignac M. Cohen K. Deiva D. Laplaud B. Bourre B. Audoin N. Collongues S. Vukusic F. Cotton R. Marignier 《Revue neurologique》2021,177(1-2):39-50
Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS. 相似文献
7.
Joshua R. Labott Cody C. Wyles Matthew T. Houdek Megha M. Tollefson David J. Driscoll William J. Shaughnessy Rafael J. Sierra 《The Journal of arthroplasty》2019,34(4):682-685
Background
Klippel-Trénaunay syndrome (KTS) is a severe vascular malformation that can lead to hypertrophic osteoarthritis. Total knee arthroplasty (TKA) performed in extremities affected with KTS is challenging given the high-risk vascular considerations and occasionally poor bone quality.Methods
We identified 12 patients with KTS who underwent TKA between 1998 and 2017. There were 7 men, mean age 42 years, and mean follow-up was 7 years. Before arthroplasty, 2 patients (17%) had preoperative sclerotherapy. Preoperative vascular studies were done for 9 patients (75%) and included magnetic resonance imaging (n = 7), magnetic resonance angiography (n = 1), and computed tomography angiography (n = 1). A preoperative blood conservation protocol was used for all operations and included the use of tranexamic acid (TXA) in later years. Posterior-stabilized TKA was used in 10 cases and cruciate-retaining TKA was used in 2 cases.Results
At final follow-up, 2 patients (17%) had undergone revision surgery: 1 for infection and 1 for tibial loosening with subsequent arthrofibrosis. Knee Society Scores (36-83, P < .0001) and functional scores (48-84, P = .0007) significantly increased between the preoperative and postoperative period. Likewise at last follow-up, the mean knee range of motion significantly increased (82°-104°, P = .04). Median blood loss for patients who received TXA was 200 mL compared to 275 mL in patients who did not receive TXA (P = .66). Likewise there was no difference (P = .5) in the proportion of patients who required a transfusion between those who received TXA (2/6, 33%) and those who did not (3/6, 50%).Conclusion
In this small series, TKA can lead to significant clinical improvement for patients with KTS. Modern blood management techniques and a careful multidisciplinary care approach render TKA a reasonable option for select patients with KTS.Level of Evidence
Level IV case series, therapeutic. 相似文献8.
Tarik D. Madni Paul A. Nakonezny Evan Barrios Jonathan B. Imran Audra T. Clark Luis Taveras Holly B. Cunningham Alana Christie Alexander L. Eastman Christian T. Minshall Stephen Luk Joseph P. Minei Herb A. Phelan Michael W. Cripps 《American journal of surgery》2019,217(1):90-97
Background
The Parkland Grading Scale for Cholecystitis (PGS) was developed as an intraoperative grading scale to stratify gallbladder (GB) disease severity during laparoscopic cholecystectomy (LC). We aimed to prospectively validate this scale as a measure of LC outcomes.Methods
Eleven surgeons took pictures of and prospectively graded the initial view of 317?GBs using PGS while performing LC (LIVE) between 9/2016 and 3/2017. Three independent surgeon raters retrospectively graded these saved GB images (STORED). The Intraclass Correlation Coefficient (ICC) statistic assessed rater reliability. Fisher's Exact, Jonckheere-Terpstra, or ANOVA tested association between peri-operative data and gallbladder grade.Results
ICC between LIVE and STORED PGS grades demonstrated excellent reliability (ICC?=?0.8210). Diagnosis of acute cholecystitis, difficulty of surgery, incidence of partial and open cholecystectomy rates, pre-op WBC, length of operation, and bile leak rates all significantly increased with increasing grade.Conclusions
PGS is a highly reliable, simple, operative based scale that can accurately predict outcomes after LC.Table of contents summary
The Parkland Grading Scale for Cholecystitis was found to be a reliable and accurate predictor of laparoscopic cholecystectomy outcomes. Diagnosis of acute cholecystitis, surgical difficulty, incidence of partial and open cholecystectomy rates, pre-op WBC, operation length, and bile leak rates all significantly increased with increasing grade. 相似文献9.
10.
Peet J. van der Vyver Farzana Paleker Martin Vorster Francois A. de Wet 《Journal of endodontics》2019,45(1):62-67