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   155篇
  免费   8篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   1篇
妇产科学   14篇
基础医学   13篇
口腔科学   10篇
临床医学   21篇
内科学   29篇
神经病学   18篇
特种医学   3篇
外科学   9篇
综合类   2篇
预防医学   13篇
眼科学   2篇
药学   22篇
中国医学   2篇
肿瘤学   3篇
  2024年   1篇
  2023年   5篇
  2022年   10篇
  2021年   18篇
  2020年   11篇
  2019年   11篇
  2018年   8篇
  2017年   7篇
  2016年   11篇
  2015年   11篇
  2014年   8篇
  2013年   14篇
  2012年   8篇
  2011年   13篇
  2010年   9篇
  2009年   1篇
  2008年   3篇
  2007年   2篇
  2006年   1篇
  2005年   2篇
  2004年   1篇
  2003年   6篇
  2002年   3篇
  1998年   1篇
排序方式: 共有165条查询结果,搜索用时 0 毫秒
21.
Objectives

The study aims to evaluate the effects of non-thermal atmospheric plasma (NTAP) treatments on dentin wetting and surface free energy (SFE) and compare the effects of NTAP treatment, etch-and-rinse, and self-etch protocols for application of universal adhesives.

Materials and methods

Mid-coronal dentin of intact third molars was used to measure contact angles of distilled water, ethylene-glycol, and diiodomethane and calculate SFE following different NTAP preset treatments (feeding gas consisting of pure He, He + 1% O2, He + 1.5% O2), power input (1 or 3 W), and tip-to-surface distance (2, 4, or 8 mm). Contact angles of reference liquids and SFE of dentin following He + 1.5% O2 at 3-W and 4-mm treatment was compared to phosphoric acid etching. Contact angles of Single Bond Universal (SBU; 3M ESPE) and Clearfil Universal Bond (CUB; Kuraray Noritake) were measured following NTAP, etch-and-rinse, and self-etch protocols.

Results

NTAP significantly reduced contact angles of reference liquids and increased dentin SFE compared to untreated dentin (p < 0.05). O2 intensified the effect of He NTAP (p < 0.05). NTAP and phosphoric acid increased dentin polarity and Lewis base surface characteristics. Phosphoric acid increased contact angles of adhesives compared to the self-etch protocol (p < 0.05). NTAP resulted in lower adhesive contact angles than phosphoric acid, the difference being statistically significant for CUB (p < 0.05). Compared to the self-etch protocol, NTAP slightly reduced CUB contact angle but not that of SBU (p > 0.05).

Conclusions

He NTAP with and without O2 increased dentin wetting and SFE, surpassing the effect of phosphoric acid and lowering adhesive contact angles. NTAP produced no apparent micro-morphological changes on dentin surface comparable to acid etching.

Clinical significance

NTAP treatment of dentin prior to adhesive application increases dentin wetting and surface free energy facilitating better adhesive distribution on dentin surface compared to phosphoric acid etching and similar to the “self-etch” application protocol.

  相似文献   
22.
Clinical and Experimental Nephrology - Acute kidney injury (AKI) is a severe complication of coronavirus disease-2019 (COVID-19). This study aims to evaluate incidence, risk factors and...  相似文献   
23.
Objectives

Comparative economic assessments of renal replacement therapies (RRT) are common and often used to inform national policy in the management of end-stage renal disease (ESRD). This study aimed to assess existing cost-effectiveness analyses of dialysis modalities and consider whether the methods applied and results obtained reflect the complexities of the real-world treatment pathway experienced by ESRD patients.

Methods

A systematic literature review (SLR) was conducted to identify cost-effectiveness studies of dialysis modalities from 2005 onward by searching Embase, MEDLINE, EBM reviews, and EconLit. Economic evaluations were included if they compared distinct dialysis modalities (e.g. in-centre haemodialysis [ICHD], home haemodialysis [HHD] and peritoneal dialysis [PD]).

Results

In total, 19 cost-effectiveness studies were identified. There was considerable heterogeneity in perspectives, time horizon, discounting, utility values, sources of clinical and economic data, and extent of clinical and economic elements included. The vast majority of studies included an incident dialysis patient population. All studies concluded that home dialysis treatment options were cost-effective interventions.

Conclusions

Despite similar findings across studies, there are a number of uncertainties about which dialysis modalities represent the most cost-effective options for patients at different points in the care pathway. Most studies included an incident patient cohort; however, in clinical practice, patients may switch between different treatment modalities over time according to their clinical need and personal circumstances.

Promoting health policies through financial incentives in renal care should reflect the cost-effectiveness of a comprehensive approach that considers different RRTs along the patient pathway; however, no such evidence is currently available.

  相似文献   
24.
25.
The present study was aimed to investigate the feasibility of loading microcrystalline cellulose derived from the agricultural waste with poorly water-soluble drug by using supercritical carbon dioxide as impregnation medium. Operating parameters of supercritical impregnation process (pressure, temperature and time) were varied to in order to maximize loading of ibuprofen used as a model drug into microcrystalline cellulose. The efficiency of ibuprofen loading using supercritical impregnation and release kinetics studies of microcrystalline cellulose in two pharmaceutical forms, powder and tablets, were investigated.The highest amount of ibuprofen was impregnated in microcrystalline cellulose powder by using supercritical impregnation at 25 MPa and 40 °C for 24 h (9.43%). Increasing pressure in the range of 10 MPa–25 MPa and time from 2 h to 24 h favours loading of ibuprofen into microcrystalline cellulose. A higher loading efficiency at the same impregnation conditions was observed for powdered microcrystalline cellulose. Temperature change in range of 40–60 °C had negligible influence on loading efficiency. FT-IR spectroscopy analysis showed no evidence of chemical modification of microcrystalline cellulose after processing. In vitro drug release study showed that impregnated powder formulations released the total amount of ibuprofen immediately, while the impregnation of microcrystalline cellulose powder in the form of tablets led to the achievement of the sustained release profile.  相似文献   
26.
We performed a basic behavioral characterization of methanol extracts of four Balkan endemic Stachys taxa: S. anisochila (SA), S. beckeana (SB), S. plumosa (SP) and S. alpina subsp. dinarica (SAD). The behavioral activity of extracts dosed intraperitoneally in the range 100–400 mg/kg was examined in adult male Wistar rats, in the elevated plus maze, spontaneous locomotor activity, and grip strength tests, mainly predictive of anxiolytic, sedative and myorelaxant actions, respectively. All investigated Stachys extracts lacked anxiolytic or myorelaxant activities, while SB at 400 mg/kg exerted an anxiogenic‐like effect. The study with the selective antagonist β‐CCt showed that the sedative effect of SAD was only partially mediated by GABAA receptors containing the α1‐subunit. While discernible, the behavioral effects of SA and SP were not distinct. In all extracts, chlorogenic acid and verbascoside were identified. In SA, SB, and SAD the flavonoid fraction was constituted of isoscutellarein and hypolaetine glycosides, while in SP chrysoeriol and apigenin glycosides were present. The results reveal the psychotropic potential of four endemic Stachys taxa, of which SAD appeared most promising as a natural sedative. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
27.
28.
The effects of aging on structural complexity in hematopoietic tissue are unknown. In this work, in a mouse experimental model, we report the age-related reduction of spleen hematopoietic tissue (SHT) complexity. Spleen tissue was obtained from the total of 64 male Swiss albino mice divided into 8 age groups: newborns (0 days old), 10 days, 20 days, 30 days, 120 days, 210 days, 300 and 390 days old. SHT was stained using conventional hematoxylin/eosin, and DNA-binding toluidine blue dyes. Fractal dimension as an indicator of cellular complexity, and lacunarity as indicator of tissue heterogeneity were determined based on the binarized SHT micrographs. Results indicate that fractal dimension of mice spleen hematopoietic tissue decreases with age, while lacunarity increases. These changes/trends have been detected in SHT stained both with toluidine blue and conventional hematoxylin/eosin. Fractal dimension was negatively correlated with lacunarity. The detected reduction in complexity suggests that age-related structural changes are present in mouse SHT both in general tissue architecture and progenitor cell DNA.  相似文献   
29.
30.
The goal of the present study was to determine the prevalence of hyperuricemia in patients with coronary artery disease (CAD), within three months after coronary events. Also, we aimed to determine whether the presence of hyperuricemia holds correlation with severe CAD, overall heart functioning and risk factors for CAD. The study included 505 consecutive CAD patients, 385 males and 120 females, aged 60.9?±?9.6 years, with a mean body mass index (BMI) 28.0?±?3.7?kg/m2. All patients were admitted to specialized cardiovascular rehabilitation within three months post-acute myocardial infarction (AMI) without revascularization (32.6%), percutaneous coronary intervention (PCI) with myocardial infarction (32.1%) and with coronary bypass graft (35.3%). The mean value of serum acidum uricum (SUA) was 345.5?±?100.3 µmol/L, where 115 (22.8%) patients had asymptomatic hyperuricemia. Patients with asymptomatic hyperuricemia had significantly higher average number of risk factors, lower HDL cholesterol and higher creatinine and triglycerides levels, lower ejection fraction (EF). Multivariate stepwise analysis revealed that five parameters were capable to predict SUA levels. We can conclude that in patients with CAD, SUA levels are independently associated with BMI, triglyceride and creatinine levels and negatively with EF. Thus, one can say that asymptomatic hyperuricemia is not significantly associated with the severity of CAD.  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