全文获取类型
收费全文 | 57645篇 |
免费 | 5039篇 |
国内免费 | 101篇 |
专业分类
耳鼻咽喉 | 671篇 |
儿科学 | 1568篇 |
妇产科学 | 1203篇 |
基础医学 | 7692篇 |
口腔科学 | 1223篇 |
临床医学 | 6341篇 |
内科学 | 11038篇 |
皮肤病学 | 850篇 |
神经病学 | 6191篇 |
特种医学 | 2481篇 |
外国民族医学 | 5篇 |
外科学 | 8186篇 |
综合类 | 859篇 |
一般理论 | 38篇 |
预防医学 | 5214篇 |
眼科学 | 1447篇 |
药学 | 4199篇 |
2篇 | |
中国医学 | 97篇 |
肿瘤学 | 3480篇 |
出版年
2021年 | 796篇 |
2020年 | 471篇 |
2019年 | 772篇 |
2018年 | 908篇 |
2017年 | 713篇 |
2016年 | 758篇 |
2015年 | 897篇 |
2014年 | 1207篇 |
2013年 | 1907篇 |
2012年 | 2685篇 |
2011年 | 2861篇 |
2010年 | 1627篇 |
2009年 | 1473篇 |
2008年 | 2605篇 |
2007年 | 2857篇 |
2006年 | 2740篇 |
2005年 | 2646篇 |
2004年 | 2565篇 |
2003年 | 2350篇 |
2002年 | 2354篇 |
2001年 | 1691篇 |
2000年 | 1663篇 |
1999年 | 1519篇 |
1998年 | 683篇 |
1997年 | 621篇 |
1996年 | 583篇 |
1995年 | 552篇 |
1994年 | 478篇 |
1993年 | 430篇 |
1992年 | 1260篇 |
1991年 | 1256篇 |
1990年 | 1168篇 |
1989年 | 1182篇 |
1988年 | 959篇 |
1987年 | 1083篇 |
1986年 | 1022篇 |
1985年 | 1030篇 |
1984年 | 830篇 |
1983年 | 688篇 |
1982年 | 455篇 |
1981年 | 421篇 |
1980年 | 412篇 |
1979年 | 737篇 |
1978年 | 550篇 |
1977年 | 475篇 |
1976年 | 480篇 |
1975年 | 423篇 |
1974年 | 539篇 |
1973年 | 490篇 |
1972年 | 413篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Alexander E. J. Trevatt David R. Thomson Robert Miller Matthew Colquhoun Akinyemi I. Idowu Shakeel Rahman 《Journal of plastic surgery and hand surgery》2019,53(2):97-104
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia. 相似文献
2.
Ingmar Fleps Pierre Guy Stephen J Ferguson Peter A Cripton Benedikt Helgason 《Journal of bone and mineral research》2019,34(10):1837-1850
The majority of hip fractures in the elderly are the result of a fall from standing or from a lower height. Current injury models focus mostly on femur strength while neglecting subject-specific loading. This article presents an injury modeling strategy for hip fractures related to sideways falls that takes subject-specific impact loading into account. Finite element models (FEMs) of the human body were used to predict the experienced load and the femoral strength in a single model. We validated these models for their predicted peak force, effective pelvic stiffness, and fracture status against matching ex vivo sideways fall impacts (n = 11) with a trochanter velocity of 3.1 m/s. Furthermore, they were compared to sideways impacts of volunteers with lower impact velocities that were previously conducted by other groups. Good agreement was found between the ex vivo experiments and the FEMs with respect to peak force (root mean square error [RMSE] = 10.7%, R2 = 0.85) and effective pelvic stiffness (R2 = 0.92, RMSE = 12.9%). The FEMs were predictive of the fracture status for 10 out of 11 specimens. Compared to the volunteer experiments from low height, the FEMs overestimated the peak force by 25% for low BMI subjects and 8% for high BMI subjects. The effective pelvic stiffness values that were derived from the FEMs were comparable to those derived from impacts with volunteers. The force attenuation from the impact surface to the femur ranged between 27% and 54% and was highly dependent on soft tissue thickness (R2 = 0.86). The energy balance in the FEMS showed that at the time of peak force 79% to 93% of the total energy is either kinetic or was transformed to soft tissue deformation. The presented FEMs allow for direct discrimination between fracture and nonfracture outcome for sideways falls and bridge the gap between impact testing with volunteers and impact conditions representative of real life falls. © 2019 American Society for Bone and Mineral Research. 相似文献
3.
4.
5.
6.
William G. Breen Krishan R. Jethwa Nathan Y. Yu Grant M. Spears William S. Harmsen Robert C. Miller Jonathan B. Ashman William G. Rule Terence T. Sio Michelle A. Neben-Wittich Michael G. Haddock Amit Mahipal Mark J. Truty Christopher L. Hallemeier Kenneth W. Merrell 《Practical radiation oncology》2021,11(1):e63-e69
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment. 相似文献
7.
8.
9.
Alan. B. Franklin Sarah N. Bevins Jeremy W. Ellis Ryan S. Miller Susan A. Shriner J. Jeffrey Root Daniel P. Walsh Thomas J. Deliberto 《Transboundary and Emerging Diseases》2019,66(2):705-714
Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade 2.3.4.4) introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade 2.3.4.4 viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade 2.3.4.4 viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security. 相似文献
10.