首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2456738篇
  免费   184259篇
  国内免费   4323篇
耳鼻咽喉   35380篇
儿科学   74525篇
妇产科学   64694篇
基础医学   344155篇
口腔科学   69551篇
临床医学   220280篇
内科学   484059篇
皮肤病学   49966篇
神经病学   206413篇
特种医学   97261篇
外国民族医学   886篇
外科学   367872篇
综合类   56567篇
现状与发展   1篇
一般理论   998篇
预防医学   198717篇
眼科学   57002篇
药学   182722篇
  61篇
中国医学   4583篇
肿瘤学   129627篇
  2019年   19441篇
  2018年   26745篇
  2017年   20335篇
  2016年   22121篇
  2015年   24933篇
  2014年   35342篇
  2013年   53615篇
  2012年   73531篇
  2011年   77056篇
  2010年   44941篇
  2009年   42688篇
  2008年   72563篇
  2007年   77071篇
  2006年   77697篇
  2005年   75748篇
  2004年   72728篇
  2003年   70052篇
  2002年   69135篇
  2001年   113587篇
  2000年   117706篇
  1999年   99280篇
  1998年   28100篇
  1997年   25664篇
  1996年   25604篇
  1995年   24722篇
  1994年   23260篇
  1993年   21642篇
  1992年   79862篇
  1991年   76901篇
  1990年   74055篇
  1989年   71293篇
  1988年   66241篇
  1987年   65210篇
  1986年   61743篇
  1985年   58797篇
  1984年   44518篇
  1983年   37916篇
  1982年   22984篇
  1981年   20441篇
  1979年   41647篇
  1978年   29193篇
  1977年   24526篇
  1976年   23002篇
  1975年   24159篇
  1974年   29965篇
  1973年   28347篇
  1972年   26496篇
  1971年   24389篇
  1970年   23048篇
  1969年   21360篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.

Aim

We herein describe the establishment of the Helsinki Vascularized Composite Allotransplantation (VCA) program and its execution in the first two face transplant cases.

Methods & patients

The Helsinki VCA program initially required the fulfillment of legal, hospital, financial, and ethical requirements. Thereafter, the assembling of a multidisciplinary team commenced. A team of Plastic, maxillofacial and ENT surgeons comprise the facial VCA team. The protocol involves collaboration with the Solid Organ Transplant (SOT) team, transplant immunology, immunosuppression, microbiology, psychiatric evaluation, well-defined VCA indications and informed consent. Between 2011 and 2017 two patients were selected for transplantation. Both patients had a severe composite facial deformity involving the maxilla and mandible following earlier ballistic injury.

Results

Patient 1 was a 35 year-old male who underwent successful near total face transplantation in February 2016 and at 30 months he has a good aesthetic outcome with symmetrical restoration of the central face and good sensory and symmetrical motor functional outcomes. Patient 2 was a 58 year-old male who underwent full face transplantation in March 2018 and at 5 months he has recovered without major problems.

Conclusion

A successful facial VCA program requires a well-prepared research protocol, experts from multiple specialties and careful patient selection. The establishment of the Helsinki VCA program required long and thorough planning and resulted in the first two Nordic face transplantation cases. This protocol now forms the platform (as a proof of concept) for other types of vascularized composite allotransplantations.  相似文献   
72.
73.

Aims

To obtain an overview of the management and outcomes of children aged 18 years or younger diagnosed with differentiated thyroid carcinoma of follicular cell origin across the UK, by collecting and analysing data from the limited number of centres treating these patients. This multicentre data might provide a more realistic perspective than single-institution series.

Materials and methods

Six centres submitted data extracted from historical records on patients aged 18 years or younger, diagnosed between 1964 and 2017. The univariate and multivariable Cox proportional hazard model was used to identify potential predictors of progression-free survival, using national data as a control.

Results

Data on 166 patients were available for analysis. Females (74%) were predominant, and the age ranged from 3 to 19 years at diagnosis, mean 14.1 years. Nodal metastases were present in 51%; 12% had distant metastases. After surgery, 95% received radioactive iodine (39% on more than one occasion) and 4% received external beam radiotherapy. With a median follow-up duration of 5 years, 69% are alive with no evidence of disease; 20% are alive with a raised thyroglobulin level as the only evidence of residual disease; 6% have residual structural disease detectable on imaging; 2% have died, from cerebral metastases.

Conclusion

Despite most patients having advanced disease at presentation, outcomes are very good. A national prospective registry should allow systematic collection of good-quality data and may facilitate research to further improve outcomes.  相似文献   
74.

Purpose

To study the use of functional capacity (FC) level and duration of aromatase inhibitor (AI) therapy with adiposity parameters in women with breast cancer.

Patients and Methods

FC was evaluated through the Health Assessment Questionnaire, which was assessed by classification and divided into 3 groups: G1 = mild to moderate difficulty, G2 = moderate to severe disability, and G3 = severe or very severe disability. Body mass, height, and waist circumference (WC) were measured, and body mass index (BMI) was calculated. Bioelectrical impedance analysis was used to calculate body fat (BF) and fat-free mass. The women were divided into 2 time groups (T1 and T2), which were determined by the median months of AI use (T1 ≤ 29.5 and T2 > 29.5 months).

Results

Impaired FC and adiposity parameters were significantly positively correlated. In addition, physical exercise was significantly lower in women assessed as G2 and G3 compared to those assessed as G1. The effect of FC on BMI, BF, and WC was also verified, as was the effect of the duration of AI receipt on BMI and BF. Women at T1 had significantly greater functional disability, BMI, and BF values. In addition, although not statistically significant, women in T1 who were assessed as G3 presented higher BMI, WC, and BF values than those in T2.

Conclusion

Adiposity above the recommended parameters and impaired FC were associated with the shortest time of receipt of adjuvant endocrine therapy with AI.  相似文献   
75.

Introduction

Malignant pleural mesothelioma (MPM) is an uncommon cancer with a poor prognosis and heterogeneous survival. Surgery for MPM is offered in some specialist centers to highly selected patients. A previously described classification and regression tree (CART) model stratified survival in unselected MPM patients using routinely collected clinical data. This study aimed to examine the performance of this CART model on a highly selected surgical population.

Methods

Data were collected from subjects undergoing cytoreductive surgery for MPM from specialist centers in Hyõgo, Japan, and Sydney, Australia, between 1991 and 2016. The CART model was applied using the combination of clinical variables to stratify subjects into risk groups (1 through 4); survival characteristics were then compared.

Results

Two hundred eighty-nine cases were included (205 from Australia, 84 from Japan). Overall median survival was 34.6 (interquartile range: 17.5–56.1) months; median age was 63.0 (interquartile range: 57.0–67.8) years, and 83.0% (n = 240) were male. There were no clinically meaningful differences between the two cohorts. Survival across the four risk groups was significantly different (p < 0.0001); the model stratified survival well with a Harrell's concordance statistic of 0.62 (95% confidence interval: 0.57–0.66) at 36 months. The group with the longest survival (median, 82.5 months) had: no weight loss, hemoglobin > 153 g/L and serum albumin > 43 g/L at time of referral to the surgical center.

Conclusions

Using routinely available clinical variables, the CART model was able to stratify surgical patients into risk groups with statistically different survival characteristics with fair to good performance. Presence of weight loss, anemia, and low albumin should confer caution when considering surgical therapy for MPM.  相似文献   
76.
77.
78.
79.
Background MMR proficient (pMMR) colorectal cancer (CRC) is usually unresponsive to immunotherapy. Recent data suggest that ibrutinib may enhance the anti-tumour activity of anti-PD-1 immunotherapy. In this study, we evaluated the safety and efficacy of ibrutinib plus pembrolizumab in refractory metastatic CRC.Methods This was a phase 1/2 study in patients with refractory metastatic pMMR CRC. The primary endpoints for phases 1 and 2 were maximum tolerated dose (MTD) and disease control rate, respectively. The secondary endpoints were safety, progression-free survival (PFS) and overall survival (OS).Results A total of 40 patients were enrolled. No dose-limiting toxicity was observed, and MTD was not identified. The highest tested dose of ibrutinib, 560 mg once daily, was combined with a fixed dose of pembrolizumab 200 mg every 3 weeks for the phase 2 portion. The most common grade 3/4 treatment-related adverse events were anaemia (21%), fatigue (8%) and elevated alkaline phosphatase (8%). Among 31 evaluable patients, 8 (26%) achieved stable disease, and no objective response was observed. The median PFS and OS were 1.4 and 6.6 months, respectively.Conclusion Ibrutinib 560 mg daily plus pembrolizumab 200 mg every 3 weeks appears to be well tolerated with limited anti-cancer activity in metastatic CRC.ClinicalTrials.gov identifier NCT03332498.Subject terms: Cancer immunotherapy, Colorectal cancer  相似文献   
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号