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   1290656篇
  免费   96949篇
  国内免费   1752篇
耳鼻咽喉   16590篇
儿科学   41930篇
妇产科学   35572篇
基础医学   192455篇
口腔科学   35288篇
临床医学   120281篇
内科学   253478篇
皮肤病学   27722篇
神经病学   103938篇
特种医学   47581篇
外国民族医学   265篇
外科学   182691篇
综合类   26463篇
现状与发展   3篇
一般理论   580篇
预防医学   106440篇
眼科学   29175篇
药学   94568篇
  8篇
中国医学   2143篇
肿瘤学   72186篇
  2019年   10624篇
  2018年   14240篇
  2017年   10898篇
  2016年   11903篇
  2015年   13742篇
  2014年   18899篇
  2013年   28557篇
  2012年   39321篇
  2011年   41758篇
  2010年   24111篇
  2009年   23154篇
  2008年   39318篇
  2007年   41926篇
  2006年   41357篇
  2005年   40438篇
  2004年   38890篇
  2003年   37154篇
  2002年   35918篇
  2001年   56914篇
  2000年   57833篇
  1999年   48797篇
  1998年   13672篇
  1997年   12432篇
  1996年   12825篇
  1995年   12099篇
  1994年   11274篇
  1993年   10547篇
  1992年   38615篇
  1991年   38051篇
  1990年   36787篇
  1989年   35574篇
  1988年   32989篇
  1987年   32304篇
  1986年   30787篇
  1985年   29057篇
  1984年   22128篇
  1983年   19363篇
  1982年   11485篇
  1979年   21088篇
  1978年   15467篇
  1977年   12875篇
  1976年   11903篇
  1975年   12865篇
  1974年   15648篇
  1973年   15412篇
  1972年   14561篇
  1971年   13595篇
  1970年   12808篇
  1969年   12091篇
  1968年   11244篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.

Aims

Variations of the anatomy of donor hepatic arteries increase the number of arterial anastomoses during liver transplantation and, possibly, the incidence of hepatic artery thrombosis (HAT). In this study, we describe the arterial anatomic variations in liver grafts procured and transplanted by a single center in Greece, the techniques of arterial anastomosis, and their effect on the incidence of early HAT.

Materials and Methods

From January 2013 to December 2017, the arterial anatomy of 116 grafts procured for liver transplantation were recorded, as well as the technique of arterial anastomosis and the incidence of early hepatic artery thrombosis (HAT <30 days).

Results

A single hepatic artery was recorded in 72.41% of the procured grafts, an aberrant left hepatic artery (accessory or replaced) in 18 grafts (15.52%), and an aberrant right hepatic artery (accessory or replaced) in 17 grafts (14.66%), while other variations were observed in less than 1% of the procured livers. Of the 116 primary liver transplantations, 6 patients (5.17%) developed early HAT <30 days. Two of these patients (1.72%) had 1 anastomosis of the hepatic artery and 4 (3.45%) had 2 anastomoses due to anatomic variations.

Conclusions

Anatomic variations of the hepatic artery in liver grafts is a common finding and increase the incidence of early HAT but not to a degree to make these grafts unusable.  相似文献   
12.
13.
14.

BACKGROUND

Online physician rating websites are increasingly used by patients to evaluate their doctors. The purpose of this investigation was to evaluate factors associated with better spine surgeon ratings.

METHODS

Orthopedic spine surgeons were randomly selected from the North American Spine Society directory utilizing a random number generator. Surgeon profiles on three physician rating websites, namely, www.HealthGrades.com, www.Vitals.com, and www.RateMDs.com, were analyzed to gather qualitative and quantitative data on patients’ perceptions of the surgeons. Independent variables from the websites were analyzed in relation to overall physician or patient satisfaction rating. Comments were coded by subject into following three categories: professional competence, bedside manner, and practice characteristics.

RESULTS

A total of 250 surgeons were evaluated, and 92% (n=230) of these doctors had at least one rating among the three websites. The surgeons with a higher average rating had significantly better trust (p<.01), scheduling (p<.01), staff (p<.01), helpfulness (p<.01), and punctuality (p<.01) scores but significantly less experience (p<.05). A linear regression model for the average rating of each surgeon (R2 value=0.754) yielded only following three significant variables: trustworthiness (p<.01), experience match (p<.05), and the average number of negative comments on surgeon's professional competence (p<.05). Trustworthiness (β=0.749) was the strongest predictor variable of physician rating, followed by the number of negative professional competence comments (β=?0.132) and experience match (β=?0.112).

CONCLUSIONS

This investigation assessed spine surgeon online patient ratings and categorized factors that patients associate with quality care. Trustworthiness was the most significant predictor of positive ratings, whereas ease of scheduling, quality of staff, helpfulness, and punctuality were also associated with higher patient ratings. Understanding what patients value may help optimize care of spine surgery patients.  相似文献   
15.
16.
ABSTRACT

Purpose

New instrument-based techniques for anterior chamber (AC) cell counting can offer automation and objectivity above clinician assessment. This review aims to identify such instruments and its correlation with clinician estimates.  相似文献   
17.
Objective: A multidisciplinary vocational rehabilitation programme, the Vocational Enablement Protocol (VEP) was developed to address the specific needs of employees with hearing difficulties. In the current study we evaluated the process of implementing the VEP in audiologic care among employees with hearing impairment. Design: In conjunction with a randomized controlled trial, we collected and analysed data on seven process parameters: recruitment, reach, fidelity, dose delivered, dose received and implemented, satisfaction, and perceived benefit. Study sample: Sixty-six employees with hearing impairment participated in the VEP. The multidisciplinary team providing the VEP comprised six professionals. Results: The professionals performed the VEP according to the protocol. Of the recommendations delivered by the professionals, 31% were perceived as implemented by the employees. Compliance rate was highest for hearing-aid uptake (51%). Both employees and professionals were highly satisfied with the VEP. Participants rated good perceived benefit from it. Conclusions: Our results indicate that the VEP could be a useful treatment for employees with hearing difficulties from a process evaluation perspective. Implementation research in the audiological setting should be encouraged in order to further provide insight into parameters facilitating or hindering successful implementation of an intervention and to improve its quality and efficacy.  相似文献   
18.
19.
20.
Objective: To examine (i) the associations between physical activity dimensions, cardiorespiratory fitness and body composition and, (ii) the associations between physical activity dimensions, cardiorespiratory fitness, body composition and biomarkers of cardiometabolic health in persons with spinal cord injury (SCI).

Methods: A cross-sectional prospective cohort study with 7-day follow-up was conducted. Body composition, cardiorespiratory fitness and biomarkers of cardiometabolic health were measured in thirty-three participants with SCI (> 1 year post injury). Physical activity dimensions were objectively assessed over 7-days.

Results: Activity energy expenditure (r =.43), physical activity level (r =.39), and moderate-to-vigorous physical activity (MVPA) (r =.48) were significantly (P < 0.001) associated with absolute (L/min) peak oxygen uptake (?O2 peak). ?O2 peak was significantly higher in persons performing ≥150 MVPA minutes/week compared to <40 minutes/week (P?=?0.003). Individual physical activity dimensions were not significantly associated with biomarkers of cardiometabolic health. However, body composition characteristics (BMI, waist and hip circumference) showed significant (P < 0.04), moderate (r >.30) associations with parameters of metabolic regulation, lipid profiles and inflammatory biomarkers. Relative ?O2 peak (ml/kg/min) was moderately associated with only insulin sensitivity (r?=?0.37, P?=?0.03).

Conclusions: Physical activity dimensions are associated with cardiorespiratory fitness; however, stronger and more consistent associations suggest that poor cardiometabolic health is associated with higher body fat content. Given these findings, the regulation of energy balance should be an important consideration for researchers and clinicians looking to improve cardiometabolic health in persons with SCI.  相似文献   

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