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   127篇
  免费   12篇
  国内免费   3篇
耳鼻咽喉   1篇
儿科学   2篇
妇产科学   4篇
基础医学   14篇
口腔科学   54篇
临床医学   8篇
内科学   21篇
皮肤病学   2篇
特种医学   1篇
外科学   16篇
综合类   4篇
预防医学   6篇
药学   6篇
肿瘤学   3篇
  2023年   1篇
  2022年   6篇
  2021年   3篇
  2020年   6篇
  2019年   9篇
  2018年   5篇
  2017年   4篇
  2016年   7篇
  2015年   8篇
  2014年   6篇
  2013年   8篇
  2012年   12篇
  2011年   13篇
  2010年   3篇
  2009年   9篇
  2008年   15篇
  2007年   10篇
  2006年   5篇
  2005年   3篇
  2004年   1篇
  2003年   4篇
  2002年   2篇
  1999年   1篇
  1991年   1篇
排序方式: 共有142条查询结果,搜索用时 31 毫秒
1.
2.
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture.  相似文献   
3.
4.
5.
Background: Subjective radiographic classifications of alveolar bone have been proposed and correlated with implant insertion torque (IT). The present diagnostic study aims to identify quantitative bone features influencing IT and to use these findings to develop an objective radiographic classification for predicting IT. Methods: Demographics, panoramic radiographs (taken at the beginning of dental treatment), and cone‐beam computed tomographic scans (taken for implant surgical planning) of 25 patients receiving 31 implants were analyzed. Bone samples retrieved from implant sites were assessed with dual x‐ray absorptiometry, microcomputed tomography, and histology. Odds ratio, sensitivity, and specificity of all variables to predict high peak IT were assessed. Results: A ridge cortical thickness >0.75 mm and a normal appearance of the inferior mandibular cortex were the most sensitive variables for predicting high peak IT (87.5% and 75%, respectively). A classification based on the combination of both variables presented high sensitivity (90.9%) and specificity (100%) for predicting IT. Conclusions: Within the limitations of this study, the results suggest that it is possible to predict IT accurately based on radiographic findings of the patient. This could be useful in the treatment plan of immediate loading cases.  相似文献   
6.

Objectives

The aim of this study was to evaluate the strength of the bond between newly introduced self-adhesive resin cements and tooth structures (i.e., enamel and dentin).

Methods

Three self-adhesive cements (SmartCem2, RelyX Unicem, seT SDI) were tested. Cylindrical-shaped cement specimens (diameter, 3 mm; height, 3 mm) were bonded to enamel and dentin. Test specimens were incubated at 37 °C for 24 h. The shear bond strength (SBS) was tested in a Zwick Roll testing machine. Results were analyzed by one-way ANOVA and t-test. Statistically significant differences were defined at the α = 0.05 level. Bond failures were categorized as adhesive, cohesive, or mixed.

Results

The SBS values ranged from 3.76 to 6.81 MPa for cements bonded to enamel and from 4.48 to 5.94 MPa for cements bonded to dentin (p > 0.05 between surfaces). There were no statistically significant differences between the SBS values to enamel versus dentin for any given cement type. All cements exhibited adhesive failure at the resin/tooth interface.

Conclusions

Regardless of their clinical simplicity, the self-adhesive resin cements examined in this study exhibit limited bond performance to tooth structures; therefore, these cements must be used with caution.  相似文献   
7.
Age changes affect the oral mucosa (the protective lining of the oral cavity), but few of these have been studied objectively. The aim of this study was to quantitatively analyse a number of morphometric parameters of the ageing oral mucosa. The fractal dimension of the epithelial connective tissue interface (ECTI) was estimated in 42 samples of normal buccal mucosa to correlate any changes in their irregularity to the age of the individuals. Morphometric parameters extracted from theoretical cell areas computed programatically were also analysed. Results showed no significant change in ECTI complexity associated with age; however, there was indication that epithelial cells tended to become larger and flatter with age. Interestingly, while some parameters did not show significant differences case wise, cluster analysis showed that the data clustered the cases into three main age groups: one representing the first two decades of life, another group represents adult life (21–50 years) and the last group representing the ageing population (50–90 years).  相似文献   
8.
Purpose: The aim of this study was to assess the effect of local melatonin administration on bone osseointegration around implants in rabbit tibiae. Material and Methods: Ten female, 6‐month‐old New Zealand rabbits were randomly divided into two groups: the experimental group, where five rabbits were treated with local application of melatonin (3 mg) to implant sites when placed into the rabbit tibia, and the control group, those who where without additive materials. Four weeks later, animals were sacrificed; tibiae were dissected from soft tissues and fixed in buffered formaldehyde, and then included in methacrylate. Histological sections were performed to be studied under light microscopy and analyzed morphometrically to evaluate the amount of bone to implant contact (BIC), trabecular area density, and cortical area density. One‐way analysis of variance test was used for statistical evaluation. p < .05 was considered to be significant. Results: Histological evaluation showed more trabecular reaction in the melatonin group. Morphometrical analysis showed a statistically significant increase in trabecular BIC in the melatonin group when compared with the control group (24.61% ± 2.87 vs 13.62% ± 1.44; p < .01). Cortical BIC was decreased in the melatonin group, without statistical significance (71.08 ± 3.63 vs 76.28 ± 2.57; p = 0.31). Trabecular area density was increased significantly in the melatonin group (8.68 ± 1.61 vs 4.02 ± 0.36; p < .05). Cortical area density was decreased significantly in the melatonin group (91.31 ± 1.6 vs 95.7 ± 0.5; p < .05). Conclusion: Within the limitation of this animal study, local melatonin application at the time of implant placement might induce more trabecular bone at implant contact and higher trabecular area density.  相似文献   
9.

Background

As countries develop economically, an “epidemiological transition” occurs whereby a set of chronic diseases increasingly becomes a country’s health challenge. Against this background, this paper examines the most common conditions associated with the prevalence of diabetes in Qatar, with a specific focus on the diabetes-obesity-hypertension nexus.

Methods

We analyzed data from the World Health Organization’s World Health Survey conducted in the State of Qatar in 2006. The survey included demographic, anthropometric, and blood chemistry measurements. Using multivariate logistical regression analysis, we assessed the most common conditions associated with diabetes, using both objective and subjective measures of diabetes. The objective measures relied on random blood sugar tests, and the subjective measure included respondents who affirmatively answered the question on diabetes diagnosis. We repeated our analysis on respondents who had blood glucose levels high enough to be considered diabetic/glucose intolerant but did not answer affirmatively on the question of diabetes diagnosis.

Results

When using the objective measure of diabetes, the following conditions appeared significant: obesity (OR?=?1.5, 95% CI?=?1.2 – 1.9), higher income (OR?=?1.4, 95% CI?=?1.0 – 1.9), high cholesterol (OR?=?1.4, 95% CI?=?1.0 – 1.9), having Qatari origin (OR?=?1.3, 95% CI?=?1.0 – 1.7), and increasing systolic blood pressure (SBP) 120–139 mmHg (OR?=?1.5, 95% CI?=?1.2 – 2.0), SBP 140–159 mmHg (OR?=?2.2, 95% CI?=?1.6 – 3.1), SBP?>?160 mmHg (OR?=?3.2, 95% CI?=?2.0 – 5.3). Similar results were obtained using the subjective measure of diabetes as a dependent variable. When applied to the group of respondents that included pre-diabetics and those who did not know they were diabetic, obesity and hypertension appeared as the only statistically significant explanatory variables.

Conclusion

High prevalence of diabetes, hypertension, and especially obesity is documented among residents of Qatar. Further steps are required to tackle the most common conditions associated with the rising diabetes epidemic in the country, which might also pose significant fiscal challenges in the future.
  相似文献   
10.
Objective To compare the efficacy and safety of intravaginal misoprostol versus dinoprostone cervical gel for cervical ripening and labour induction. Methods We carried out an experimental clinical trial in which we enrolled 130 cervical consecutive patients with cervical ripening, randomly assigned to one of the following two treatment groups: (1) intravaginal misoprostol and (2) intracervical dinoprostone gel. A total of 50 μm of misoprostol was placed in the posterior vaginal fornix every 6 h for a maximum period of 24 h and 0.5 mg of dinoprostone was administrated in the uterine cervix every 6 h, for a maximum period of 24 h. The primary outcome measure was the number (rate) of women who went to vaginally deliver within 24 h of the protocol initiation. Results Among 130 patients evaluated, 65 were allocated to the misoprostol group and 65 to the dinoprostone group. The proportion of vaginal delivery within 24 h was significantly higher in the misoprostol group (75%) than in the dinoprostone group (53.8%) (RR = 1.40, 95% CI [1.07–1.45], P = 0.02). There was no significant difference between the mean time interval of delivery in the misoprostol group and the dinoprostone group (14.9 vs.15.8 h) (P = 0.51). The Bishop score was significantly higher in the misoprostol group, 6 h after the onset of the study (1.38; relative risk, 95% CI [1.02–1.85], P = 0.03). The Caesarean delivery rate for fetal distress was higher in the dinoprostone group (21 vs. 10.8%, P = 0.15). The tachysystole (Misoprostol 6.1% vs. dinoprostone 4.6%, relative risk 1.15, 95% CI [0.6–2.24]) and hyperstimulation syndrome rates (Misoprostol 7.6% vs. dinoprostone 4.6%, relative risk 1.26, 95% CI [0.72–2.24]) were slightly increased in the misoprostol group than in the dinoprostone group without reaching the level of statistical signification. Conclusion Misoprostol as used in this protocol is more effective than cervical dinoprostone gel application in the cervical ripening and labour induction. There is a tendency for an increase in the rate of tachysystole and hyperstimulation syndrome.  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