全文获取类型
收费全文 | 7693篇 |
免费 | 429篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 88篇 |
儿科学 | 264篇 |
妇产科学 | 200篇 |
基础医学 | 674篇 |
口腔科学 | 227篇 |
临床医学 | 757篇 |
内科学 | 1937篇 |
皮肤病学 | 151篇 |
神经病学 | 364篇 |
特种医学 | 218篇 |
外国民族医学 | 3篇 |
外科学 | 1514篇 |
综合类 | 144篇 |
一般理论 | 1篇 |
预防医学 | 421篇 |
眼科学 | 210篇 |
药学 | 569篇 |
中国医学 | 34篇 |
肿瘤学 | 409篇 |
出版年
2023年 | 76篇 |
2022年 | 174篇 |
2021年 | 347篇 |
2020年 | 175篇 |
2019年 | 260篇 |
2018年 | 369篇 |
2017年 | 224篇 |
2016年 | 230篇 |
2015年 | 212篇 |
2014年 | 420篇 |
2013年 | 494篇 |
2012年 | 685篇 |
2011年 | 716篇 |
2010年 | 383篇 |
2009年 | 298篇 |
2008年 | 458篇 |
2007年 | 464篇 |
2006年 | 428篇 |
2005年 | 346篇 |
2004年 | 337篇 |
2003年 | 281篇 |
2002年 | 302篇 |
2001年 | 60篇 |
2000年 | 30篇 |
1999年 | 34篇 |
1998年 | 44篇 |
1997年 | 35篇 |
1996年 | 35篇 |
1995年 | 27篇 |
1994年 | 20篇 |
1993年 | 18篇 |
1992年 | 13篇 |
1991年 | 12篇 |
1990年 | 12篇 |
1989年 | 14篇 |
1988年 | 10篇 |
1987年 | 12篇 |
1986年 | 7篇 |
1985年 | 12篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 7篇 |
1980年 | 12篇 |
1979年 | 4篇 |
1977年 | 10篇 |
1976年 | 5篇 |
1974年 | 4篇 |
1972年 | 8篇 |
1968年 | 5篇 |
排序方式: 共有8185条查询结果,搜索用时 0 毫秒
1.
2.
3.
Yinong Young-Xu Julia Thornton Snider Robertus van Aalst Salaheddin M. Mahmud Edward W. Thommes Jason K.H. Lee David P. Greenberg Ayman Chit 《Vaccine》2019,37(11):1484-1490
Background
Observational studies of the relative effectiveness of influenza vaccines are essential for public health decision making. Their estimates, however, are subject to bias due to unmeasured confounders. Instrumental variable (IV) methods can control for observed and unobserved confounders.Methods
We used linked electronic medical record databases in the Veterans Health Administration (VHA) as well as Medicare administrative files to examine the relative vaccine effectiveness (rVE) of high-dose influenza vaccine (HD) versus standard-dose influenza vaccines (SD) in preventing hospitalizations among VHA-enrolled Veterans ≥65?years of age during 5 influenza seasons (2010–2011 through 2014–2015). Using multivariable IV Poisson regression modeling to address unmeasured confounding and bias, we analyzed the data by each season and through longitudinal analysis of all five seasons.Findings
We included 3,638,924 person–influenza seasons of observation where 158,636 (4%) were among HD vaccine recipients and 3,480,288 (96%) were among SD vaccine recipients. Of the 1,728,562 Veterans, 1,702,824 (98.5%) were male and 1,299,412 (75%) were non-Hispanic white. Based on the longitudinal analysis of all five seasons, the IV-adjusted rVE estimate of HD vs. SD was 10% (95% CI, 8–12%) against all-cause hospitalization; 18% (95% CI, 15–21%) against cardiorespiratory-associated hospitalization; and 14% (95% CI, 6–22%) against influenza/pneumonia-associated hospitalization. The findings by season were similar.Interpretation
Our analysis of VHA clinical data collected from approximately 1.7 million Veterans 65?years and older during five seasons demonstrates that high-dose influenza vaccine is more effective than standard-dose influenza vaccines in preventing influenza- or pneumonia-associated hospitalizations, cardiorespiratory hospitalizations, and all-cause hospitalizations. 相似文献4.
Walid K. Abu Saleh Phillip Mason Odeaa Al Jabbari Hany Samir Brian A. Bruckner 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(6):569-571
The Impella 5.0, a percutaneously inserted left ventricular assist device, has been used to support patients who have severe heart failure or who are undergoing high-risk percutaneous coronary intervention. We report our surgical placement of the Impella 5.0, through a graft sewn to the aorta, to unload the left ventricle of a 59-year-old man who was undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy shock. The patient underwent successful placement of a long-term left ventricular assist device before his discharge from the hospital. The versatility of the Impella 5.0 is exemplified in this patient who was successfully bridged to long-term support. 相似文献
5.
6.
Samir K El-Mofty Sushama Patil 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(3):339-345
We have recently shown that HPV-positive tonsillar carcinoma in young patients exhibits nonkeratinizing basaloid morphology and a characteristic immunophenotype. The purpose of this study was to review a large number of cases of oropharyngeal carcinomas, in all age groups, and to identify tumors with nonkeratinizing morphology. Using polymerase chain reaction (PCR) the prevalence and type of HPV DNA was determined in representative cases and in a control group of conventional keratinizing squamous cell carcinomas. The tumors were further characterized with a panel of immunohistochemical stains. A total of 235 carcinomas were reviewed; 141 of the tonsils and 94 in the base of tongue. Ninety (36%) of the tonsillar and 30 (32%) of the base of tongue carcinomas were nonkeratinizing (NKCa) with basal cell features; the rest were classical keratinizing squamous cell carcinomas (KSCC). HPV DNA, particularly type 16, was identified in 10 (100%) of 10 of NKCA and in only 2 (20%) of 10 of KSCC (P = .0014). NKCas were strongly reactive to p16 antibodies while KSCC showed weak and focal reactivity. Higher Ki67 and lower p53 staining scores were observed in NKCa as compared to KSCC. It is concluded that NKCa of the tonsils and base of tongue is a distinct subtype of squamous cell carcinoma of the head and neck with high prevalence of HPV DNA and a characteristic immunophenotype. 相似文献
7.
Samir Kumar Praharaj mbbs md dpm Nishant Goyal mbbs md dpm Sukanto Sarkar mbbs md dpm Dhruv Bagati mbbs Prakriti Sinha mp hil Vinod Kumar Sinha mbbs md dpm 《Psychiatry and clinical neurosciences》2009,63(2):230-234
Reported herein is a case of obsessive–compulsive disorder with persistent and distressing musical obsessions along with other symptoms. Advanced source analysis of electroencephalographic data indicated high spectral power over the bifrontal region. The musical symptoms were resistant to pharmacotherapy but there was some reduction in frequency and duration of musical obsessions with thought-stopping technique. 相似文献
8.
9.
Ayman Agha Gabriel Glockzin Matthias Woenckhaus Wolfgang Dietmaier Igors Iesalnieks Hans J. Schlitt 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):671-677
Background Insular thyroid carcinoma was described as a tumor with aggressive behavior, and patients usually present themselves with
an advanced tumor stage. Whether the insular component is an independent factor for poor prognosis remains unclear. Therefore,
in the present study, we compared the survival of patients with advanced insular, follicular, and papillary thyroid cancer.
Materials and methods The clinical behavior of tumors in three groups of patients with T4 thyroid carcinoma—8 patients with insular, 11 patients
with follicular, and 21 patients with papillary thyroid carcinomas—was compared. Disease-free survival and disease-specific
death were analyzed statistically. Cox regression analysis was used to evaluate the influence of histotype and other prognostic
factors.
Results At 3 years, survival was 37.5% (mean 26 months) among patients with insular thyroid carcinoma, 80% (mean 59 months) among
those with follicular, and 89% (mean 126 months) among those with papillary thyroid carcinomas (p = 0.007). Disease-free survival in patients without initial distant metastasis was worst in patients with insular thyroid
carcinoma (20%) compared to those with follicular (75%) and those with papillary thyroid carcinomas (71%).
Conclusion Patients with advanced insular thyroid carcinoma have a poorer outcome in comparison to patients with similar advanced stage
who have follicular or papillary thyroid carcinoma. 相似文献
10.
In this study, we examined the impact of surgeon handedness on total knee arthroplasty (TKA) outcomes. From 1997 to 2001, a right-handed surgeon performed 728 primary TKAs while standing on the side of the operative extremity--377 on the right and 351 on the left. Extension and Knee Society Function and Pain scores were significantly better for right knees than for left knees 1 year after surgery. This is the first report that shows that handedness can play a role in TKA outcomes. Reasons for the difference have not been determined but may be related to dexterity or proprioception. A surgeon should be aware of this potential problem and take precautions to prevent diminished results when operating. 相似文献