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   293639篇
  免费   22524篇
  国内免费   1170篇
耳鼻咽喉   3397篇
儿科学   7665篇
妇产科学   5822篇
基础医学   39422篇
口腔科学   5556篇
临床医学   30968篇
内科学   61235篇
皮肤病学   3947篇
神经病学   27601篇
特种医学   9764篇
外国民族医学   12篇
外科学   43999篇
综合类   4336篇
一般理论   341篇
预防医学   25813篇
眼科学   7203篇
药学   20317篇
  6篇
中国医学   418篇
肿瘤学   19511篇
  2023年   1489篇
  2022年   2664篇
  2021年   5961篇
  2020年   3622篇
  2019年   5915篇
  2018年   6659篇
  2017年   4975篇
  2016年   5593篇
  2015年   6474篇
  2014年   9508篇
  2013年   13220篇
  2012年   19816篇
  2011年   20779篇
  2010年   11626篇
  2009年   10386篇
  2008年   18269篇
  2007年   19160篇
  2006年   18981篇
  2005年   18937篇
  2004年   17763篇
  2003年   16610篇
  2002年   15685篇
  2001年   3639篇
  2000年   3172篇
  1999年   3667篇
  1998年   3633篇
  1997年   3040篇
  1996年   2595篇
  1995年   2531篇
  1994年   2162篇
  1993年   1957篇
  1992年   2364篇
  1991年   2196篇
  1990年   2020篇
  1989年   1908篇
  1988年   1831篇
  1987年   1834篇
  1986年   1805篇
  1985年   1840篇
  1984年   1909篇
  1983年   1716篇
  1982年   1777篇
  1981年   1649篇
  1980年   1500篇
  1979年   1276篇
  1978年   1180篇
  1977年   990篇
  1976年   947篇
  1975年   748篇
  1974年   847篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments.  相似文献   
4.
5.
6.

Background

Obesity is a risk factor for acetabular component malposition when total hip arthroplasty is performed with manual techniques. The utility of imageless navigation in obese patients remains unknown. This study compared the accuracy and precision of imageless navigation for component orientation between obese and nonobese patients.

Methods

A total of 459 total hip arthroplasties performed for osteoarthritis using imageless navigation were reviewed from a single surgeon’s institutional review board–approved database. Einzel-Bild-Roentgen Analyse determined component orientation on 6-week postoperative anteroposterior radiographs. Mean orientation error (accuracy) and precision were compared between obese (body mass index ≥ 30 kg/m2) and nonobese patients. Regression analysis evaluated the influence of obesity on component position.

Results

The difference in mean inclination and anteversion between obese and nonobese groups was 1.1° (43.0° ± 3.5°; range, 35.8°-57.8° vs 41.9° ± 4.4°; range, 33.0°-57.1° and 24.9° ± 6.3°; range, 14.2°-44.3° vs 23.8° ± 6.6°; range, 7.0°-38.6°, respectively). Inclination precision was better for nonobese patients. No difference in inclination accuracy or anteversion accuracy or precision was detected between groups. And 83% of components were placed within the target range. There was no relationship between obesity (dichotomized) and component placement outside the target ranges for inclination, anteversion, or both. As a continuous variable, increased body mass index correlated with higher odds of inclination outside the target zone (odds ratio, 1.06; P = .001).

Conclusion

Using imageless navigation, inclination orientation was less precise for obese patients, but the observed difference is likely not clinically relevant. Accurate superficial registration of landmarks in obese patients is achievable, and the use of imageless navigation similarly improves acetabular component positioning in obese and nonobese patients.

Level of Evidence

Therapeutic Level IV.  相似文献   
7.
8.
9.

Background

Nursing Home Compare (NHC) ratings, created and maintained by Medicare, are used by both hospitals and consumers to aid in the skilled nursing facility (SNF) selection process. To date, no studies have linked NHC ratings to actual episode-based outcomes. The purpose of this study was to evaluate whether NHC ratings are valid predictors of 90-day complications, readmission, and bundle costs for patients discharged to an SNF after primary total joint arthroplasty (TJA).

Methods

All SNF-discharged primary TJA cases in 2017 at a multihospital academic health system were queried. Demographic, psychosocial, and clinical variables were manually extracted from the health record. Medicare NHC ratings were then collected for each SNF. For patients in the Medicare bundle, postacute and total bundle cost was extracted from claims.

Results

Four hundred eighty-eight patients were discharged to a total of 105 unique SNFs. In multivariate analysis, overall NHC rating was not predictive of 90-day readmission/major complications, >75th percentile postacute cost, or 90-day bundle cost exceeding the target price. SNF health inspection and quality measure ratings were also not predictive of 90-day readmission/major complications or bundle performance. A higher SNF staffing rating was independently associated with a decreased odds for >75th percentile 90-day postacute spend (odds ratio, 0.58; P = .01) and a 90-day bundle cost exceeding the target price (odds ratio = 0.69; P = .02) but was similarly not predictive of 90-day readmission/complications.

Conclusion

Results of our study suggest that Medicare's NHC tool is not a useful predictor of 90-day costs, complications, or readmissions for SNFs within our health system.  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