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   3011624篇
  免费   254545篇
  国内免费   28729篇
耳鼻咽喉   40322篇
儿科学   86910篇
妇产科学   74503篇
基础医学   486513篇
口腔科学   78595篇
临床医学   274423篇
内科学   514917篇
皮肤病学   81976篇
神经病学   254300篇
特种医学   116425篇
外国民族医学   203篇
外科学   465213篇
综合类   122127篇
现状与发展   70篇
一般理论   2077篇
预防医学   241443篇
眼科学   69910篇
药学   214403篇
  186篇
中国医学   20149篇
肿瘤学   150233篇
  2022年   30740篇
  2021年   64395篇
  2020年   42249篇
  2019年   63898篇
  2018年   75866篇
  2017年   58629篇
  2016年   63655篇
  2015年   81488篇
  2014年   117598篇
  2013年   181418篇
  2012年   89217篇
  2011年   87215篇
  2010年   120828篇
  2009年   124769篇
  2008年   68555篇
  2007年   69071篇
  2006年   80252篇
  2005年   75719篇
  2004年   74049篇
  2003年   64655篇
  2002年   53824篇
  2001年   82493篇
  2000年   74527篇
  1999年   79998篇
  1998年   65054篇
  1997年   63488篇
  1996年   60104篇
  1995年   55441篇
  1994年   49314篇
  1993年   45845篇
  1992年   50868篇
  1991年   47214篇
  1990年   43794篇
  1989年   44092篇
  1988年   40705篇
  1987年   39500篇
  1986年   37157篇
  1985年   37741篇
  1984年   37226篇
  1983年   34915篇
  1982年   37677篇
  1981年   35782篇
  1980年   33774篇
  1979年   28198篇
  1978年   27461篇
  1977年   26209篇
  1976年   23285篇
  1975年   21274篇
  1974年   20226篇
  1973年   19267篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.

Background and aims

It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.

Methods and results

As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women.

Conclusions

In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes.  相似文献   
102.
103.
Parhiala  P.  Ranta  K.  Gergov  V.  Kontunen  J.  Law  R.  La Greca  A. M.  Torppa  M.  Marttunen  M. 《School mental health》2020,12(2):265-283

In order to offer early and accessible treatment for adolescents with depression, brief and effective treatments in adolescents’ everyday surroundings are needed. This randomized controlled trial studied the preliminary effectiveness, feasibility, and acceptability of interpersonal counseling (IPC) and brief psychosocial support (BPS) in school health and welfare services. The study was conducted in the 28 lower secondary schools of a large city in Southern Finland, randomized to provide either IPC or BPS. Help-seeking 12–16-year-old adolescents with mild-to-moderate depression, with and without comorbid anxiety, were included in the study. Fifty-five adolescents received either 6 weekly sessions of IPC or BPS and two follow-up sessions. Outcome measures included self- and clinician-rated measures of depression, global functioning, and psychological distress/well-being. To assess feasibility and acceptability of the treatments, adolescents’ and counselors’ treatment compliance and satisfaction with treatment were assessed. Both treatments were effective in reducing depressive disorders and improving adolescents’ overall functioning and well-being. At post-treatment, in both groups, over 50% of adolescents achieved recovery based on self-report and over 70% based on observer report. Effect sizes for change were medium or large in both groups at post-treatment and increased at 6-month follow-up. A trend indicating greater baseline symptom severity among adolescents treated in the IPC-providing schools was observed. Adolescents and counselors in both groups were satisfied with the treatment, and 89% of the adolescents completed the treatments and follow-ups. This trial suggests that both IPC and BPS are feasible, acceptable, and effective treatments for mild-to-moderate depression in the school setting. In addition, IPC seems effective even if comorbid anxiety exists. Our study shows that brief, structured interventions, such as IPC and BPS, are beneficial in treating mild-to-moderate depression in school settings and can be administered by professionals working at school.

Trial registrationhttp://www.clinicaltrials.gov. Unique identifier: NCT03001245.

  相似文献   
104.
ABSTRACT

Purpose

To investigate the effect of 1% tropicamide on anterior chamber aqueous flare (ACAF) measurements acquired with laser flare meter in patients with pseudoexfoliation.  相似文献   
105.
Abstract

Purpose: In the context of assistive technology, mobility takes the meaning of “moving safely, gracefully, and comfortably”.The aim of this article is to provide a system which will be a convenient means of navigation for the Visually Impaired people, in the public transport system.

Method: A blind regular commuter who travels by public transport facility finds difficulty in identifying the vehicle that is nearing the stop. Hence, a real-time system that dynamically identifies the nearing vehicle and informs the commuters is necessary. This paper proposes such a system namely the “Vehicle Board Recognition System” (VBRS). Computer Vision techniques such as segmentation, object recognition, text detection and optical character recognition are utilized to build the system, which will detect, analyze, derive and communicate the information to the passengers.

Results: Thanks to the rapid development in technology, there are several navigation systems both hand held and wearable, available to help visually impaired (VI) people move comfortably both indoor and outdoor. Many blind people are not comfortable in using these devices or they are not affordable for them. Thus the proposed system gives them the comfort of navigation.

Conclusion: This system can be installed in the bus stop to assist the Visually Impaired, from externally rather than their hand held or wearable assistive devices.
  • Implications for rehabilitation
  • This proposed system will help the visually impaired to

  • ensure secure navigation

  • be independent of the others

  • develop self confidence.

  • overcome the training, affordability of wearable/ handheld devices.

  相似文献   
106.
107.
108.
109.

Introduction

The nature of community pharmacy is changing, shifting from the preparation and distribution of medicines to the provision of cognitive pharmaceutical services (CPS); however, often the provision of traditional services leaves little time for innovative services. This study investigated the time community pharmacists spend on the tasks and activities of daily practice and to what extent they are able to implement CPS-related services in daily practice.

Methods

Self-reporting work sampling was used to register the activities of community pharmacists. A smartphone application, designed specifically for this purpose, alerted participants to register their current activity five times per working day for 6 weeks. Participants also completed an online survey about baseline characteristics.

Results

Ninety-one Dutch community pharmacists provided work-sampling data (7848 registered activities). Overall, 51.5% of their time was spent on professional activities, 35.4% on semi-professional activities, and 13.1% on non-professional activities. The proportion of time devoted to CPS decreased during the workweek, whereas the time spent on traditional task increased.

Discussion and conclusion

This study shows it is feasible to collect work-sampling data using smartphone technology. Community pharmacists spent almost half of their time on semi-professional and non-professional activities, activities that could be delegated to other staff members. In practice, the transition to CPS is hampered by competing traditional tasks, which prevents community pharmacists from profiling themselves as pharmaceutical experts in daily practice.  相似文献   
110.
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