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   81102篇
  免费   5460篇
  国内免费   269篇
耳鼻咽喉   1197篇
儿科学   2232篇
妇产科学   1556篇
基础医学   9113篇
口腔科学   1616篇
临床医学   8437篇
内科学   16386篇
皮肤病学   1248篇
神经病学   7761篇
特种医学   2954篇
外国民族医学   5篇
外科学   14037篇
综合类   1110篇
一般理论   113篇
预防医学   7121篇
眼科学   1533篇
药学   5362篇
  1篇
中国医学   120篇
肿瘤学   4929篇
  2023年   410篇
  2022年   313篇
  2021年   1665篇
  2020年   1044篇
  2019年   1706篇
  2018年   2009篇
  2017年   1460篇
  2016年   1496篇
  2015年   1657篇
  2014年   2519篇
  2013年   3561篇
  2012年   5389篇
  2011年   5629篇
  2010年   3104篇
  2009年   2772篇
  2008年   4956篇
  2007年   5225篇
  2006年   5051篇
  2005年   5079篇
  2004年   4808篇
  2003年   4371篇
  2002年   4049篇
  2001年   953篇
  2000年   864篇
  1999年   990篇
  1998年   786篇
  1997年   639篇
  1996年   580篇
  1995年   616篇
  1994年   591篇
  1993年   499篇
  1992年   665篇
  1991年   638篇
  1990年   532篇
  1989年   532篇
  1988年   504篇
  1987年   460篇
  1986年   458篇
  1985年   541篇
  1984年   551篇
  1983年   502篇
  1982年   590篇
  1981年   553篇
  1980年   499篇
  1979年   326篇
  1978年   333篇
  1977年   337篇
  1975年   281篇
  1974年   266篇
  1973年   265篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.

Objective

To examine the experience of interracial anxiety among health professionals and how it may affect the quality of their interactions with patients from racially marginalized populations. We explored the influence of prior interracial exposure—specifically through childhood neighborhoods, college student bodies, and friend groups—on interracial anxiety among medical students and residents. We also examined whether levels of interracial anxiety change from medical school through residency.

Data Source

Web-based longitudinal survey data from the Medical Student Cognitive Habits and Growth Evaluation Study.

Study Design

We used a retrospective longitudinal design with four observations for each trainee. The study population consisted of non-Black US medical trainees surveyed in their 1st and 4th years of medical school and 2nd and 3rd years of residency. Mixed effects longitudinal models were used to assess predictors of interracial anxiety and assess changes in interracial anxiety scores over time.

Principal Findings

In total, 3155 non-Black medical trainees were followed for 7 years. Seventy-eight percent grew up in predominantly White neighborhoods. Living in predominantly White neighborhoods and having less racially diverse friends were associated with higher levels of interracial anxiety among medical trainees. Trainees' interracial anxiety scores did not substantially change over time; interracial anxiety was highest in the 1st year of medical school, lowest in the 4th year, and increased slightly during residency.

Conclusions

Neighborhood and friend group composition had independent effects on interracial anxiety, indicating that premedical racial socialization may affect medical trainees' preparedness to interact effectively with diverse patient populations. Additionally, the lack of substantial change in interracial anxiety throughout medical training suggests the importance of providing curricular tools and structure (e.g., instituting interracial cooperative learning activities) to foster the development of healthy interracial relationships.  相似文献   
2.
Knox  Joseph A.  Kumar  Vishal  Conrad  Miles B.  Nanavati  Sujal  Moore  Teri  Wilson  Mark 《Emergency radiology》2022,29(3):605-609
Emergency Radiology - Access to multi-detector computed tomography (MDCT) scanning for interventional procedures can prove to be logistically challenging as resources are often in different areas...  相似文献   
3.
4.
5.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz -  相似文献   
6.
7.
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   
8.

Background

Patients undergoing cardiac surgery are at significant risk of developing postoperative acute kidney injury (AKI). Neutrophil–lymphocyte ratio (NLR) is a widely available inflammatory biomarker which may be of prognostic value in this setting.

Methods

We conducted a systematic review and meta-analysis of studies reporting associations between perioperative NLR with postoperative AKI. We searched Medline, Embase and the Cochrane Library, without language restriction, from inception to May 2022 for relevant studies. We meta-analysed the reported odds ratios (ORs) with 95% confidence intervals (CIs) for both elevated preoperative and postoperative NLR with risk of postoperative AKI and need for renal replacement therapy (RRT). We conducted a meta-regression to explore inter-study statistical heterogeneity.

Results

Twelve studies involving 10,724 participants undergoing cardiac surgery were included, with eight studies being deemed at high risk of bias using PROBAST modelling. We found statistically significant associations between elevated preoperative NLR and postoperative AKI (OR 1.45, 95% CI 1.18–1.77), as well as postoperative need for RRT (OR 2.37, 95% CI 1.50–3.72). Postoperative NLR measurements were not of prognostic significance.

Conclusions

Elevated preoperative NLR is a reliable inflammatory biomarker for predicting AKI following cardiac surgery.  相似文献   
9.
The impact of vaccination and new SARS-CoV-2 variants on peri-operative outcomes is unclear. We aimed to update previously published consensus recommendations on timing of elective surgery after SARS-CoV-2 infection to assist policymakers, administrative staff, clinicians and patients. The guidance remains that patients should avoid elective surgery within 7 weeks of infection, unless the benefits of doing so exceed the risk of waiting. We recommend individualised multidisciplinary risk assessment for patients requiring elective surgery within 7 weeks of SARS-CoV-2 infection. This should include baseline mortality risk calculation and assessment of risk modifiers (patient factors; SARS-CoV-2 infection; surgical factors). Asymptomatic SARS-CoV-2 infection with previous variants increased peri-operative mortality risk three-fold throughout the 6 weeks after infection, and assumptions that asymptomatic or mildly symptomatic omicron SARS-CoV-2 infection does not add risk are currently unfounded. Patients with persistent symptoms and those with moderate-to-severe COVID-19 may require a longer delay than 7 weeks. Elective surgery should not take place within 10 days of diagnosis of SARS-CoV-2 infection, predominantly because the patient may be infectious, which is a risk to surgical pathways, staff and other patients. We now emphasise that timing of surgery should include the assessment of baseline and increased risk, optimising vaccination and functional status, and shared decision-making. While these recommendations focus on the omicron variant and current evidence, the principles may also be of relevance to future variants. As further data emerge, these recommendations may be revised.  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