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   2229859篇
  免费   156203篇
  国内免费   5381篇
耳鼻咽喉   30041篇
儿科学   72499篇
妇产科学   60308篇
基础医学   322413篇
口腔科学   61679篇
临床医学   208059篇
内科学   424497篇
皮肤病学   47245篇
神经病学   178627篇
特种医学   84389篇
外国民族医学   563篇
外科学   321948篇
综合类   47245篇
现状与发展   2篇
一般理论   697篇
预防医学   175780篇
眼科学   50287篇
药学   170766篇
  12篇
中国医学   5563篇
肿瘤学   128823篇
  2019年   17681篇
  2018年   25162篇
  2017年   19315篇
  2016年   21320篇
  2015年   24032篇
  2014年   33120篇
  2013年   50062篇
  2012年   68691篇
  2011年   72888篇
  2010年   42662篇
  2009年   39490篇
  2008年   67080篇
  2007年   71493篇
  2006年   71965篇
  2005年   69010篇
  2004年   65945篇
  2003年   63137篇
  2002年   61092篇
  2001年   108725篇
  2000年   111721篇
  1999年   93571篇
  1998年   25131篇
  1997年   22418篇
  1996年   22140篇
  1995年   20961篇
  1994年   19392篇
  1993年   18194篇
  1992年   72534篇
  1991年   70457篇
  1990年   68842篇
  1989年   65682篇
  1988年   60213篇
  1987年   58908篇
  1986年   55802篇
  1985年   52908篇
  1984年   39119篇
  1983年   33200篇
  1982年   19187篇
  1979年   35405篇
  1978年   24563篇
  1977年   20935篇
  1976年   19478篇
  1975年   20878篇
  1974年   25001篇
  1973年   24394篇
  1972年   22806篇
  1971年   21316篇
  1970年   19713篇
  1969年   18445篇
  1968年   17103篇
排序方式: 共有10000条查询结果,搜索用时 2 毫秒
1.
Detailed contemporary knowledge of the characteristics of the surgical population, national anaesthetic workload, anaesthetic techniques and behaviours are essential to monitor productivity, inform policy and direct research themes. Every 3–4 years, the Royal College of Anaesthetists, as part of its National Audit Projects (NAP), performs a snapshot activity survey in all UK hospitals delivering anaesthesia, collecting patient-level encounter data from all cases under the care of an anaesthetist. During November 2021, as part of NAP7, anaesthetists recorded details of all cases undertaken over 4 days at their site through an online survey capturing anonymous patient characteristics and anaesthetic details. Of 416 hospital sites invited to participate, 352 (85%) completed the activity survey. From these, 24,177 reports were returned, of which 24,172 (99%) were included in the final dataset. The work patterns by day of the week, time of day and surgical specialty were similar to previous NAP activity surveys. However, in non-obstetric patients, between NAP5 (2013) and NAP7 (2021) activity surveys, the estimated median age of patients increased by 2.3 years from median (IQR) of 50.5 (28.4–69.1) to 52.8 (32.1–69.2) years. The median (IQR) BMI increased from 24.9 (21.5–29.5) to 26.7 (22.3–31.7) kg.m–2. The proportion of patients who scored as ASA physical status 1 decreased from 37% in NAP5 to 24% in NAP7. The use of total intravenous anaesthesia increased from 8% of general anaesthesia cases to 26% between NAP5 and NAP7. Some changes may reflect the impact of the COVID-19 pandemic on the anaesthetic population, though patients with confirmed COVID-19 accounted for only 149 (1%) cases. These data show a rising burden of age, obesity and comorbidity in patients requiring anaesthesia care, likely to impact UK peri-operative services significantly.  相似文献   
2.

Aims

Concomitant chemoradiation is the standard of care in patients with inoperable non-small cell lung cancer. The purpose of this study was to analyse the survival outcome and toxicity data of using hypofractionated chemoradiation.

Materials and methods

One hundred patients were treated from June 2011 to November 2016. Treatment consisted of 55 Gy in 20 daily fractions concurrently with split-dose cisplatin vinorelbine chemotherapy over 4 weeks followed by two cycles of cisplatin vinorelbine only. Survival was estimated using Kaplan–Meier and Cox regression was carried out for known prognostic factors. A systematic search of literature was conducted using Medline, Embase and Cochrane databases and relevant references included.

Results

In total, 97% of patients completed radiotherapy and 73% of patients completed all four cycles of chemotherapy. One patient died of a cardiac event during consolidative chemotherapy. There were two cases of grade 4 toxicities (one sepsis, one renal impairment). Grade 3 toxicities included nausea/vomiting (17%), oesophagitis (15%), infection with neutropenia (12%) and pneumonitis (4%). Clinical benefit was seen in 86%. Two-year progression-free survival and overall survival rates were 49% and 58%, respectively. The median progression-free survival and overall survival were 23.4 and 43.4 months, respectively. The only significant prognostic factor was the number of chemotherapy cycles received (P = 0.02). The systematic review identified 13 relevant studies; a variety of regimens were assessed with variable reporting of outcomes and toxicity but with overall an improvement in survival over time.

Conclusion

Our experience compared with the original phase II trial showed improved treatment completion rates and survival with acceptable morbidity. With appropriate patient selection this regimen is an effective treatment option for locally advanced non-small cell lung cancer. This study helps to benchmark efficacy and toxicity rates while considering the addition of new agents to hypofractionated concurrent chemoradiotherapy. The agreement of a standard regimen for assessment in future trials would be beneficial.  相似文献   
3.
4.
Abstract

Introduction: ASPIRE Excellence Awards in Student Assessment are offered to medical schools with innovative and comprehensive assessment programmes adjudged by international experts, using evidence-based criteria.

The journeys of three ASPIRE-winning medical schools toward “assessment excellence” are presented. These schools include Aga Khan University Medical College (AKU-MC), Pakistan, Southern Illinois University School of Medicine (SIUSOM), USA, and University of Leeds School of Medicine, UK.

Methods: The unfolding journeys highlighting achievements, innovations, and essential components of each assessment programme were compared to identify differences and commonalities.

Results: Cultural contextual differences included developed-versus-developing country, east-west, type of regulatory bodies, and institutional-versus-national certifying/licensing examinations, which influence curricula and assessments.

In all, 12 essential commonalities were found: alignment with institutional vision; sustained assessment leadership; stakeholder engagement; communication between curriculum and assessment; assessment-for-learning and feedback; longitudinal student profiling of outcome achievement; assessment rigor and robustness; 360° feedback from-and-to assessment; continuous enrichment through rigorous quality assurance; societal sensitivity; influencing others; and a “wow factor.”

Conclusions: Although the journeys of the three medical schools were undertaken in different cultural contexts, similar core components highlight strong foundations in student assessment. The journeys continue as assessment programmes remain dynamic and measurement science expands. This article may be helpful to other institutions pursuing excellence in assessment.  相似文献   
5.
Background: In an interprofessional training ward (ITW), students from different health professions collaboratively perform patient care with the goal of improving patient care. In the past two decades, ITWs have been established world-wide and studies have investigated their benefits. We aimed to compare ITWs with respect to their logistics, interprofessional learning outcomes and patient outcomes.

Methods: We explored PubMed, CINAHL, Web of Science and EMBASE (1990–June 2017) and included articles focusing on interprofessional, in-patient training wards with student teams of medical and other health professions students. Two independent reviewers screened studies for eligibility and extracted data.

Results: Thirty-seven articles from twelve different institutions with ITWs were included. ITWs world-wide are organized similarly with groups of 2–12 students (i.e. medical, nursing, physiotherapy, occupational therapy, and pharmacy) being involved in patient care, usually for a period of two weeks. However, the type of clinical ward and the way supervisors are trained differ.

Conclusions: ITWs show promising results in short-term student learning outcomes and patient satisfaction rates. Future ITW studies should measure students’ long-term interprofessional competencies using standardized tools. Furthermore, a research focus on the impact of ITWs on patient satisfaction and relevant patient care outcomes is important.  相似文献   

6.
Background: The use of improvizational theater (“improv”) in health professional education (“medical improv”) is an emerging field. However, optimal curricular design features and learning outcomes have not yet been systematically described.

Objective: To synthesize evidence on learning outcomes and curricular design elements of improvizational theater training in health professions education.

Methods: A literature search with keywords “Improv” and “Improvisational Theatre” was undertaken in January 2016 in Ovid MEDLINE, CINHAL, EMBASE, SCOPUS, Web of Science, and ERIC, with an accompanying gray literature search. Four authors coded and achieved consensus on themes relating to curricular design elements and learning outcomes, which were mapped onto the CanMEDS framework.

Results: Seven articles met inclusion criteria. Key curricular design features included (i) facilitators with dual clinical and theater expertise; (ii) creating a low-stakes environment; and (iii) engaging in debrief to highlight clinical relevance. Improv curricula were found to impact most CanMEDS roles, including: Medical Expert (comfort with uncertainty); Leader (team management); Scholar (feedback, self-reflection); Communicator (empathy, active listening, non-verbal communication); Collaborator (culture of trust); and Professional (resiliency and confidence). Mechanisms by which improv may promote acquisition of these professional competencies, and the utility of improv in areas such as interprofessional team development, leadership, and wellness and resiliency are discussed.  相似文献   

7.

Aims

The 2014 British Thyroid Association thyroid cancer guidelines recommend lifelong follow-up of thyroid cancer patients. This is probably unnecessary, can cause patient anxiety, is time consuming and places significant demand on National Health Service resources. It has been suggested that low-risk differentiated thyroid cancer (DTC) patients could be discharged to primary care once they are 5 years from diagnosis and treatment. The aim of this study was to investigate the potential safety of this practice.

Materials and methods

In total, 756 patients with dynamically risk-stratified (DRS) low-risk/excellent response to treatment DTC treated over 2001–2013 in the Leeds region were followed after diagnostic surgery and the recurrence rate calculated.

Results

The median follow-up time was nearly 10 years (5–17 years). Radiological recurrence occurred in 13/756 (1.7%) patients and was always preceded by raised thyroglobulin/ thyroglobulin antibody levels. In all 13 patients elevation of thyroglobulin occurred within 5 years of diagnosis. Two additional patients were found to have rising thyroglobulin at almost 9 and 10.5 years from diagnosis, although to date radiological recurrence has not been detected. Assuming these two patients developed recurrence with longer duration of follow-up, then 0.26% (2/756) of patients would not have their recurrence discovered within 5 years of diagnosis. To detect 100% of patients with a putative recurrence in our cohort would require 10.5 years of follow-up. Four patients had transiently raised thyroglobulin, which became undetectable within 2 years (in three patients), without any treatment and radiological recurrence was not discovered.

Conclusion

Discharge of DRS low-risk DTC patients to primary care after 5 years of secondary care follow-up is reasonable, accepting that late recurrence may occur in a very small minority of individuals (0.26%, ~1:400). A more cautious approach would be to continue monitoring for 10 years, although the frequency of assessments could be reduced with increasing duration of follow-up.  相似文献   
8.
Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS.  相似文献   
9.

Background

The Parkland Grading Scale for Cholecystitis (PGS) was developed as an intraoperative grading scale to stratify gallbladder (GB) disease severity during laparoscopic cholecystectomy (LC). We aimed to prospectively validate this scale as a measure of LC outcomes.

Methods

Eleven surgeons took pictures of and prospectively graded the initial view of 317?GBs using PGS while performing LC (LIVE) between 9/2016 and 3/2017. Three independent surgeon raters retrospectively graded these saved GB images (STORED). The Intraclass Correlation Coefficient (ICC) statistic assessed rater reliability. Fisher's Exact, Jonckheere-Terpstra, or ANOVA tested association between peri-operative data and gallbladder grade.

Results

ICC between LIVE and STORED PGS grades demonstrated excellent reliability (ICC?=?0.8210). Diagnosis of acute cholecystitis, difficulty of surgery, incidence of partial and open cholecystectomy rates, pre-op WBC, length of operation, and bile leak rates all significantly increased with increasing grade.

Conclusions

PGS is a highly reliable, simple, operative based scale that can accurately predict outcomes after LC.

Table of contents summary

The Parkland Grading Scale for Cholecystitis was found to be a reliable and accurate predictor of laparoscopic cholecystectomy outcomes. Diagnosis of acute cholecystitis, surgical difficulty, incidence of partial and open cholecystectomy rates, pre-op WBC, operation length, and bile leak rates all significantly increased with increasing grade.  相似文献   
10.
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