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   589篇
  免费   59篇
  国内免费   11篇
儿科学   17篇
妇产科学   13篇
基础医学   68篇
口腔科学   6篇
临床医学   56篇
内科学   192篇
皮肤病学   2篇
神经病学   14篇
特种医学   65篇
外科学   65篇
综合类   12篇
预防医学   46篇
眼科学   2篇
药学   50篇
中国医学   1篇
肿瘤学   50篇
  2021年   4篇
  2020年   5篇
  2019年   11篇
  2018年   7篇
  2017年   7篇
  2016年   9篇
  2015年   17篇
  2014年   11篇
  2013年   14篇
  2012年   20篇
  2011年   17篇
  2010年   24篇
  2009年   16篇
  2008年   28篇
  2007年   29篇
  2006年   37篇
  2005年   22篇
  2004年   22篇
  2003年   11篇
  2002年   13篇
  2001年   13篇
  2000年   13篇
  1999年   11篇
  1998年   17篇
  1997年   12篇
  1996年   14篇
  1995年   22篇
  1994年   6篇
  1993年   9篇
  1992年   16篇
  1991年   14篇
  1990年   16篇
  1989年   29篇
  1988年   19篇
  1987年   10篇
  1986年   19篇
  1985年   18篇
  1984年   3篇
  1983年   5篇
  1982年   5篇
  1981年   4篇
  1980年   7篇
  1978年   4篇
  1977年   7篇
  1976年   8篇
  1975年   7篇
  1974年   3篇
  1973年   3篇
  1968年   4篇
  1967年   3篇
排序方式: 共有659条查询结果,搜索用时 15 毫秒
1.
Endoscopic retrograde cholangiopancreatography(ERCP) is the preferred procedure for biliary and pancreatic drainage.While ERCP is successful in about 95% of cases,a small subset of cases are unsuccessful due to altered anatomy,peri-ampullary pathology,or malignant obstruction.Endoscopic ultrasound-guided drainage is a promising technique for biliary,pancreatic and recently gallbladder decompression,which provides multiple advantages over percutaneous or surgical biliary drainage.Multiple retrospective and some prospective studies have shown endoscopic ultrasoundguided drainage to be safe and effective.Based on the currently reported literature,regardless of the approach,the cumulative success rate is 84%-93% with an overall complication rate of 16%-35%.endoscopic ultrasoundguided drainage seems a viable therapeutic modality for failed conventional drainage when performed by highly skilled advanced endoscopists at tertiary centers with expertise in both echo-endoscopy and therapeutic endoscopy  相似文献   
2.
Abstract: Aim: To compare plaque removal efficacy of Oral‐B CrossAction (CA) used for 1 min with an American Dental Association (ADA) manual toothbrush used for 2 or 5 min in an examiner‐blind, three‐treatment, six‐period crossover study. Materials and methods: After refraining from all oral hygiene procedures for 23–25 h, subjects were randomly assigned to one of nine possible six‐period (visit) treatment sequences. Plaque was assessed at baseline (Rustogi Modified Navy Plaque Index). Post‐brushing scores were recorded after brushing with a marketed dentifrice and the assigned toothbrush for the specified duration. The same procedure was followed at each of six subsequent visits. Clinical measurements were carried out by the same examiner. Results: Forty subjects completed the study. All three treatments effectively removed plaque from the whole mouth, along the gingival margin and from approximal surfaces. Whole mouth and gingival margin plaque removal scores with CA for 1 min did not differ significantly from scores with the ADA toothbrush used for 2 min. The ADA brush used for 5 min showed significantly greater whole mouth (P < 0.001) and gingival margin (P < 0.001) plaque reduction than the two other treatments. Approximal plaque removal scores did not differ between the three treatments. Conclusions: Efficient plaque removal can be achieved after 1 min of brushing with CA. The amount of plaque removed did not differ significantly from that achieved with the ADA brush after 2 min of brushing. Greater whole mouth and gingival margin plaque removal scores were seen with the ADA brush after 5 min.  相似文献   
3.
The Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial was designed to determine whether maintenance interferon therapy could slow disease progression in patients who had failed to eradicate hepatitis C virus (HCV) during prior interferon treatment (nonresponders). Ten clinical sites, a virological testing center, and a data coordinating center (DCC) were selected to collaborate in the design and implementation of the final protocol. Eligible patients had been treated previously with interferon for at least 12 weeks, with or without another antiviral, ribavirin, but still had persistent viremia. Because patients had received a variety of prior treatments, and as a perceived benefit of enrollment, we incorporated a Lead-in period of treatment with long-acting pegylated interferon alfa-2a plus ribavirin into the study design, a combination believed to be more effective but not approved by the Food and Drug Administration at the Trial's inception. If patients failed to achieve clearance of virus from the blood after 20 weeks of this Lead-in therapy, they were entered into the main trial at week 24 and randomized to receive either a lower dose of pegylated interferon weekly alone or no further therapy for an additional 3 1/2 years. The original protocol was amended later in three respects to improve enrollment and to adapt to Food and Drug Administration approval of the Lead-in therapy, including allowing patients to proceed directly to the randomized part of the study if treatment resembling the Lead-in had been completed. The protocol changes enhanced enrollment while upholding the original goals of the study and its integrity.  相似文献   
4.
5.
Respiratory insufficiency in neuronopathic and neuropathic disorders   总被引:1,自引:0,他引:1  
Twenty-nine patients with a neuronopathic or neuropathic disorder were referred for assessment of respiratory insufficiency between 1978 and 1994. Diagnoses included spinal muscular atrophy (6), chronic idiopathic demyelinating neuropathy (4), Vialetto-van Laere syndrome (3), hereditary motor and sensory neuropathy (3) and a miscellaneous group (5). We also describe seven patients with Guillain-Barre syndrome (GBS) who required long-term ventilatory support for over 6 months to 7 years after the initial illness. Respiratory insufficiency occurred as a consequence of respiratory muscle weakness, impaired bulbar function and restrictive lung defects. In some groups presentation was with progressive nocturnal hypoventilation culminating in acute respiratory failure. Five patients with GBS or chronic idiopathic demyelinating neuropathy were weaned from ventilatory support up to 18 months after the initial illness. The remaining 24 patients required continuous or nocturnal ventilatory support using intermittent positive-pressure ventilation (13), negative pressure ventilation (4), nasal-mask-delivered intermittent positive-pressure ventilation (4), nasal-mask-delivered continuous positive-pressure ventilation (3), mouthpiece-assisted ventilation by day (2) and rocking bed (1). None have been weaned from support after a period of ventilation ranging from one month to 10 years. Eight patients have subsequently died.   相似文献   
6.
Current regulatory review standards emphasize the hospital's role in providing continuum of care. Today, patient care staff must know more about the "continuum of care" concept so they can help patients more fully understand their treatment and take an active role in their own care. One of the challenges is finding creative and effective ways to get the message across to everyone on the staff. This article describes one approach to self-directed learning that takes into consideration individual learning styles and level of proficiency with a focus on the continuum of patient care.  相似文献   
7.
8.
Increased superoxide production by phagocytic NADPH oxidase has been associated with inflammatory conditions. Growing evidences suggest that dietary polyphenols may modulate the expression of NADPH oxidase subunits. Herein, we examined whether soluble mate tea (SMT) consumption – a polyphenol-rich beverage – affects the expression of the leukocyte NADPH oxidase protein p47phox and/or circulating biomarkers of inflammation and antioxidant biomarkers in humans. In a two-phase study, nine men were requested to drink water (control) for 8 d and then follow a second 8-d period drinking SMT. Blood samples were analysed for p47phox protein in CD16+/CD14? cells, interleukin (IL)-1β (IL-1β), tumour necrosis factor-alpha (TNF-α), IL-6, total phenols, and reduced and oxidised glutathione (GSH and GSSG, respectively) after each study phase. After SMT intake, CD16+/CD14? cells' p47phox protein and serum TNF-α and IL-6 levels were significantly attenuated (P?<?.05) while plasma phenolic compounds and blood GSH:GSSG ratio were significantly enhanced (P?<?.05). Consumption of SMT favourably affected leukocytes' p47phox expression and inflammatory cytokine and antioxidants levels in peripheral blood, which may help decrease oxidative stress and low-grade inflammation.  相似文献   
9.
10.

Objective

To assess whether, 5 years into the HITECH programs, national data reflect a consistent relationship between EHR adoption and hospital outcomes across three important dimensions of hospital performance.

Data Sources/Study Setting

Secondary data from the American Hospital Association and CMS (Hospital Compare and EHR Incentive Programs) for nonfederal, acute‐care hospitals (2009–2012).

Study Design

We examined the relationship between EHR adoption and three hospital outcomes (process adherence, patient satisfaction, efficiency) using ordinary least squares models with hospital fixed effects. Time‐related effects were assessed through comparing the impact of EHR adoption pre (2008/2009) versus post (2010/2011) meaningful use and by meaningful use attestation cohort (2011, 2012, 2013, Never). We used a continuous measure of hospital EHR adoption based on the proportion of electronic functions implemented.

Data Collection/Extraction Methods

We created a panel dataset with hospital‐year observations.

Principal Findings

Higher levels of EHR adoption were associated with better performance on process adherence (0.147; p < .001) and patient satisfaction (0.118; p < .001), but not efficiency (0.01; p = .78). For all three outcomes, there was a stronger, positive relationship between EHR adoption and performance in 2010/2011 compared to 2008/2009. We found mixed results based on meaningful use attestation cohort.

Conclusions

Performance gains associated with EHR adoption are apparent in more recent years. The large national investment in EHRs appears to be delivering more consistent benefits than indicated by earlier national studies.  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