全文获取类型
收费全文 | 4097篇 |
免费 | 255篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 138篇 |
妇产科学 | 91篇 |
基础医学 | 405篇 |
口腔科学 | 121篇 |
临床医学 | 562篇 |
内科学 | 774篇 |
皮肤病学 | 147篇 |
神经病学 | 353篇 |
特种医学 | 444篇 |
外科学 | 487篇 |
综合类 | 106篇 |
一般理论 | 2篇 |
预防医学 | 300篇 |
眼科学 | 51篇 |
药学 | 215篇 |
中国医学 | 4篇 |
肿瘤学 | 219篇 |
出版年
2021年 | 55篇 |
2020年 | 36篇 |
2019年 | 71篇 |
2018年 | 59篇 |
2017年 | 45篇 |
2016年 | 58篇 |
2015年 | 62篇 |
2014年 | 74篇 |
2013年 | 94篇 |
2012年 | 171篇 |
2011年 | 171篇 |
2010年 | 129篇 |
2009年 | 142篇 |
2008年 | 168篇 |
2007年 | 196篇 |
2006年 | 175篇 |
2005年 | 178篇 |
2004年 | 139篇 |
2003年 | 149篇 |
2002年 | 144篇 |
2001年 | 145篇 |
2000年 | 174篇 |
1999年 | 91篇 |
1998年 | 114篇 |
1997年 | 93篇 |
1996年 | 82篇 |
1995年 | 76篇 |
1994年 | 68篇 |
1993年 | 71篇 |
1992年 | 80篇 |
1991年 | 74篇 |
1990年 | 76篇 |
1989年 | 82篇 |
1988年 | 80篇 |
1987年 | 77篇 |
1986年 | 63篇 |
1985年 | 72篇 |
1984年 | 52篇 |
1983年 | 40篇 |
1982年 | 32篇 |
1981年 | 30篇 |
1979年 | 30篇 |
1978年 | 33篇 |
1977年 | 36篇 |
1976年 | 26篇 |
1975年 | 27篇 |
1972年 | 24篇 |
1971年 | 24篇 |
1970年 | 23篇 |
1967年 | 24篇 |
排序方式: 共有4427条查询结果,搜索用时 10 毫秒
131.
132.
European Randomised Study of Screening for Prostate Cancer (ERSPC) risk calculators significantly outperform the Prostate Cancer Prevention Trial (PCPT) 2.0 in the prediction of prostate cancer: a multi‐institutional study 下载免费PDF全文
133.
The surgical management of early stage endometrial carcinoma is controversial. The benefits of pelvic lymphadenectomy and administration of radiotherapy in this group have been disputed. We aimed to document the experience of stage 1 endometrial carcinoma at the National Maternity Hospital during the 10 year period 1989-1998 and to evaluate and compare clinical outcomes between retrospectively-assigned low and high-risk tumour groups. Seventy seven women were diagnosed with Stage 1 endometrial carcinoma in this period. Thirty-nine women had low-risk and 38 had high-risk tumours. Women with high-risk tumours were older and had a higher rate of lymph-vascular space invasion by tumour on histological examination. Three women (3.9%) developed disease recurrence and died of their disease; one low-risk and two high-risk tumour patients. Survival without recurrence did not differ between the two risk groups. No consistent pattern existed in surgical staging between the two risk groups. A prospectively-assigned definition of risk would minimise variations in clinical practice by providing a basis for a more tailored approach to adjuvant treatments. 相似文献
134.
Gray foxes (Urocyon cinereoargenteus) as a potential reservoir of a Bartonella clarridgeiae-like bacterium and domestic dogs as part of a sentinel system for surveillance of zoonotic arthropod-borne pathogens in northern California 总被引:2,自引:0,他引:2 下载免费PDF全文
Henn JB Gabriel MW Kasten RW Brown RN Theis JH Foley JE Chomel BB 《Journal of clinical microbiology》2007,45(8):2411-2418
Two species of Bartonella, a novel Bartonella clarridgeiae-like bacterium and B. vinsonii subsp. berkhoffii, were isolated from rural dogs and gray foxes in northern California. A novel B. clarridgeiae-like species was isolated from 3 (1.7%) of 182 dogs and 22 (42%) of 53 gray foxes, while B. vinsonii subsp. berkhoffii was isolated from 1 dog (0.5%) and 5 gray foxes (9.4%). PCR and DNA sequence analyses of the citrate synthase (gltA) gene and the 16S-23S intergenic spacer region suggested that strains infecting dogs and gray foxes were identical. Fifty-four dogs (29%) and 48 gray foxes (89%) had reciprocal titers of antibodies against Bartonella spp. of > or =64. The high prevalence of bacteremia and seroreactivity to Bartonella spp. in gray foxes suggests that they may act as a reservoir species for the B. clarridgeiae-like species in this region. Domestic dogs were also tested for other arthropod-borne infectious agents. Fifty-one dogs (28%) were positive for Dirofilaria immitis antigen, seventy-four (40%) were seroreactive to Anaplasma phagocytophilum, and five (2.7%) were seropositive for Yersinia pestis. Fourteen dogs (7.6%) were PCR positive for A. phagocytophilum. Polytomous logistic regression models were used to assess the association of Bartonella antibody titer categories with potential risk factors and the presence of other vector-borne agents in domestic dogs. Older dogs were more likely to be seroreactive to Bartonella spp. There was no association between the exposure of dogs to Bartonella and the exposure of dogs to A. phagocytophilum in this study. 相似文献
135.
Wang B Lau KA Ong LY Shah M Steain MC Foley B Dwyer DE Chew CB Kamarulzaman A Ng KP Saksena NK 《Virology》2007,367(2):288-297
136.
The objective of our work has been to investigate the use of ultrasound image-guided high-intensity focused ultrasound (HIFU)
to non-invasively produce conduction block in rabbit sciatic nerves in vivo, a technique that could become a treatment of spasticity and pain. The work reported here involved the investigation of the
duration of such conduction blocks after HIFU treatment and whether they resulted in axon degeneration. The right sciatic
nerves of 12 rabbits were treated, under guidance of ultrasound imaging, with repeated 5-s applications of 3.2 MHz HIFU with
in situ intensity of 1930 W/cm2 (spatial-average, temporal-average) until conduction block was achieved. Survival endpoints were 0, 7, or 14 days after HIFU
treatment, at which point the nerve conduction was assessed. Qualitative and quantitative histological analysis of nerve sections
proximal and distal to the HIFU site was performed. Conduction block of all 12 nerves was achieved with average HIFU treatment
time of 10.5±4.9 s (mean±SD). The volume of necrosis of adjacent muscle was measured to be 1.59±1.1 cm3 (mean±SD). For all nerves, conduction block remained at the survival endpoint and the block resulted in degeneration of axons
distal to the HIFU site, as confirmed by electrophysiological and histological methods. Potential clinical applications include
treatment of spasticity in patients with spinal cord injury or pain in cancer patients. 相似文献
137.
138.
L Jones J Moir C Brown R Williams JJ French 《Annals of the Royal College of Surgeons of England》2014,96(6):e1-e3
A 61-year-old man presented with jaundice, and subsequently underwent an extended left hepatectomy and pancreaticoduodenectomy for a cholangiocarcinoma invading the head of the pancreas. The patient developed sepsis due to a biliary leak at the hepaticojejunostomy. We describe the original use of a biodegradable stent, deployed via percutaneous transhepatic cholangiography into the Roux limb, resulting in good drainage and resolution of sepsis. The chief benefit of this procedure is the lack of need for subsequent removal as well as purported reduced biofilm accumulation. We believe this to be the first reported case of this type and the literature surrounding the subject is also discussed. 相似文献
139.
Norah A. Foster Dawn M. Elfenbein Wayne Kelley Christopher R. Brown Carolyn Foley John E. Scarborough Steven N. Vaslef Mark L. Shapiro 《The spine journal》2014,14(7):1147-1154
Background contextThe use and need of helicopter aeromedical transport systems (HEMSs) in health care today is based on the basic belief that early definitive care improves outcomes. Helicopter aeromedical transport system is perceived to be safer than ground transport (GT) for the interfacility transfer of patients who have sustained spinal injury because of the concern for deterioration of neurologic function if there is a delay in reaching a higher level of care. However, the use of HEMS is facing increasing public scrutiny because of its significantly greater cost and unique risk profile.PurposeThe aim of the study was to determine whether GT for interfacility transfer of patients with spinal injury resulted in less favorable clinical outcomes compared with HEMS.Study design/settingRetrospective review of all patients transferred to a Level 1 trauma center.Patient samplePatients identified from the State Trauma Registry who were initially seen at another hospital with an isolated diagnosis of injury to the spine and then transferred to a Level 1 trauma center over a 2-year period.Outcome measuresNeurologic deterioration, disposition from the emergency department, in-hospital mortality, interfacility transfer time, hospital length of stay, nonroutine discharge, and radiographic evidence of worsening spinal injury.MethodsPatients with International Classification of Diseases, Ninth Revision (ICD-9) codes for injury to the spine were selected and records were reviewed for demographics and injury details. All available spine radiographs were reviewed by an orthopedic surgeon blinded to clinical data and transport type. Chi-square and t tests and multivariate linear and logistic regression models were done using STATA version 10.ResultsA total of 274 spine injury patients were included in our analysis, 84 (31%) of whom were transported by HEMS and 190 (69%) by GT. None of the GT patients had any deterioration in neurologic examination nor any detectable alteration in the radiographic appearance of their spine injury attributable to the transportation process. Helicopter aeromedical transport system resulted in significantly less transfer time with an average time of 80 minutes compared with 112 minutes with GT (p<.001). Ultimate disposition included 175 (64%) patients discharged to home, 15 (5%) expired patients, and 84 (31%) discharged to extended care facilities. After adjusting for patient age and Injury Severity Score, the use of GT was not a significant predictor of in-hospital mortality (odds ratio, 1.4; 95% confidence interval, 0.3–5), hospital length of stay (11.2+1.3 vs. 9.5+0.8 days, p=.3), or nonroutine discharge (odds ratio, 1.1; 95% confidence interval, 0.5–2.2).ConclusionsGround transport for interfacility transfer of patients with spinal injury appears to be safe and suitable for patients who lack other compelling reasons for HEMS. A prospective analysis of transportation mode in a larger cohort of patients is needed to verify our findings. 相似文献
140.