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   106篇
  免费   15篇
  国内免费   1篇
儿科学   3篇
基础医学   14篇
口腔科学   4篇
临床医学   8篇
内科学   36篇
皮肤病学   1篇
神经病学   8篇
特种医学   2篇
外科学   12篇
综合类   2篇
预防医学   8篇
眼科学   1篇
药学   9篇
肿瘤学   14篇
  2024年   1篇
  2023年   3篇
  2022年   6篇
  2021年   15篇
  2020年   10篇
  2019年   11篇
  2018年   11篇
  2017年   8篇
  2016年   6篇
  2015年   8篇
  2014年   10篇
  2013年   4篇
  2012年   6篇
  2011年   9篇
  2010年   2篇
  2009年   2篇
  2008年   4篇
  2007年   3篇
  2006年   1篇
  2005年   1篇
  2002年   1篇
排序方式: 共有122条查询结果,搜索用时 46 毫秒
1.
PurposeTo identify influence of different values of age and abnormal bowel length in HD patients selected for single stage TERPT which affects the technique of surgery.MethodsThis observational study was carried out for over 2.5 years. All children younger than 14 years old with clinical suspicion for HD, typical transitional zone (TZ) on contrast enema (CE) distal to splenic flexure, preoperative diagnosis approved by full thickness biopsy, no previous surgical history and no urgency were included. The distance between the anus and TZ was considered as aganglionic length on CE. Biopsy was taken from distal to proximal of resected bowel to reach circumferentially normal innervated bowel. Paired sample Student's t-test, Pearson correlation test, receiver operating characteristic (ROC) analysis were performed.ResultsForty-eight patients were enrolled in this study. Measured mean for aganglionic bowel length on CE and pathology were 33.5 ± 17.1 cm and 56.8 ± 33.5 cm, respectively (p < 0.01). Correlation coefficient (R) and coefficient of determination (R2) were 0.632 and 40%, respectively (p < 0.01). The difference between radiologic and pathologic measurements in females was higher than males (mean: 29.3 vs 21.9 cm) but was not statistically significant (p = 0.75). There was statistically significant difference between CE and pathologic results in the infants younger than 10 months (p = .004). Abnormal bowel length equal to 52 cm predicted requirement of laparoscopy assistance/laparotomy with 75% sensitivity and 85% specificity.ConclusionOur investigation showed it is safe to attempt for single stage TERPT when aganglionic length on CE is less than 52 cm and the child with HD is older than 10 months. Chance of requiring additional laparotomy or laparoscopy assistance is low in these patients.Type of studyStudy of diagnostic test.Level of evidenceLevel II.  相似文献   
2.
ObjectiveMicro-nano scale surface modification of Ti-6Al-4V was investigated through the fascinated modern fiber engraving laser method. The process was performed at a high laser speed of 2000 mm/s, under different laser frequencies (20–160 kHz) and groove distances (0.5–50 μm).MethodsTopographic evaluations such as Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FE-SEM) were used to identify the quality and regularity of patterns. The proliferation of human osteoblast-like osteosarcoma cells (MG63) was analyzed by MTT assay for up to 72 h. Also, the plate counting method was used to quantify the viability potential of the modified surface against Escherichia coli bacteria.ResultsThe cellular viability of the sample modified at the laser frequency of 20 kHz and grooving distance of 50 μm increased up to 35 and 10% compared to the non-treated and control samples, respectively. In the case of the surface modification at lower grooving distances range between 0.5–50 μm, the maximum laser frequency (160 kHz) applied leads to lower pulse’s energies and less bacterial adhesion. Otherwise, at groove distances more than 50 μm, the minimum laser frequency (20 kHz) applied reduces the laser pulse overlaps, increases the cell adhesion and antibacterial properties.SignificanceSurface modification by the fiber engraving laser process significantly enhances the cell adhesion on the surface. As a result of such roughness and cell adhesion enhancement, the surface toxicity feature diminished, and its antibacterial properties improved.  相似文献   
3.
4.
This study compared the push‐out bond strength of mineral trioxide aggregate (MTA) and a new endodontic cement (NEC) as root‐end filling materials in root‐end cavities prepared by ultrasonic technique (US) or Er,Cr:YSGG laser (L). Eighty single‐rooted extracted human teeth were endodontically treated, apicectomised and randomly divided into four following groups (n = 20): US/MTA, US/NEC, L/MTA and L/NEC. In US/MTA and US/NEC groups, root‐end cavities were prepared with ultrasonic retrotip and filled with MTA and NEC, respectively. In L/MTA and L/NEC groups, root‐end cavities were prepared using Er,Cr:YSGG laser and filled with MTA and NEC, respectively. Each root was cut apically to create a 2 mm‐thick root slice for measurement of bond strength using a universal testing machine. Then, all slices were examined to determine the mode of bond failure. Data were analysed using two‐way anova . Root‐end filling materials showed significantly higher bond strength in root‐end cavities prepared using ultrasonic technique (US/MTA and US/NEC) (P < 0.001). The bond strengths of MTA and NEC did not differ significantly. The failure modes were mainly adhesive for MTA, but cohesive for NEC. In conclusion, bond strengths of MTA and NEC to root‐end cavities were comparable and higher in ultrasonically prepared cavities.  相似文献   
5.
6.
7.
We studied 19 patients with pericardial disease using two‐dimensional and three‐dimensional transthorathic echocardiography (2DTTE and 3DTTE, respectively) in order to determine whether 3DTTE provides incremental value on top of 2DTTE in the evaluation of these patients. With 3DTTE a more comprehensive assessment of pericardial effusion can be made and both the parietal and visceral layers of the pericardium can be visualized en face and examined for pathologies and fibrin deposits. In our series of patients, 3DTTE was superior to 2DTTE in uncovering mass lesions involving the pericardium such as tuberculous granulomas and metastatic disease. Furthermore, it provided a better assessment of the nature of pericardial lesions, such as pericardial and mediastinal hematomas, pericardial cysts, and metastatic disease to the pericardium by sequential cropping of the 3D data sets and visualizing the interior of the lesions in a manner not possible with 2DTTE. It was also valuable in determining the extent of pericardial calcification in pericardial constriction and in measuring the size of pericardial masses. These preliminary results suggest the superiority of 3DTTE over 2DTTE in the evaluation of pericardial diseases and that it provides incremental knowledge to the echocardiographer. (ECHOCARDIOGRAPHY, Volume 26, November 2009)  相似文献   
8.
9.

Context

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease, with 5-10% of liver having extra fat. Increase in its prevalence in all age groups is linked with obesity and Type II diabetes. The treatment of NAFLD remains controversial. A growing body of evidence suggests a relation between overgrowth of gut microbiota with NAFLD and non-alcoholic steatohepatitis (NASH). The objective of this review is to provide an overview on experimental and clinical studies assessing all positive and negative effects of probiotics.

Evidence Acquisition

We made a critical appraisal on various types of documents published from 1999 to March 2012 in journals, electronic books, seminars, and symposium contexts including Medline, PubMed, and Cochrane Central Register of Controlled Trials databases. We used the key words: “non-alcoholic fatty liver disease, probiotics, non-alcoholic steatohepatitis, liver disease, and fatty liver”.

Results

Probiotics, as biological factors, control the gut microbiota and result in its progression. It is in this sense that they are suggestive of a new and a natural way of promoting liver function. Correspondingly, limited evidence suggests that probiotics could be considered as a new way of treatment for NAFLD.

Conclusions

Various experimental studies and clinical trials revealed promising effects of probiotics in improving NAFLD; however given the limited experience in this field, generalization of probiotics as treatment of NAFLD needs substantiation through more trials with a larger sample sizes and with longer-term follow up.  相似文献   
10.
Background Tracking medical student clinical encounters is now an accreditation requirement of medical schools. The use of handheld computers for electronic logging is emerging as a strategy to achieve this.
Objectives To evaluate the technical feasibility and student satisfaction of a novel electronic logging and feedback program using handheld computers in the emergency department.
Methods This was a survey study of fourth-year medical student satisfaction with the use of their handheld computers for electronic logging of patient encounters and procedures. The authors also included an analysis of this technology.
Results Forty-six students participated in this pilot project, logging a total of 2,930 encounters. Students used the logs an average of 7.6 shifts per rotation, logging an average of 8.3 patients per shift. Twenty-nine students (63%) responded to the survey. Students generally found it easy to complete each encounter (69%) and easy to synchronize their handheld computer with the central server (83%). However, half the students (49%) never viewed the feedback Web site and most (79%) never reviewed their logs with their preceptors. Overall, only 17% found the logging program beneficial as a learning tool.
Conclusions Electronic logging by medical students during their emergency medicine clerkship has many potential benefits as a method to document clinical encounters and procedures performed. However, this study demonstrated poor compliance and dissatisfaction with the process. In order for electronic logging using handheld computers to be a beneficial educational tool for both learners and educators, obstacles to effective implementation need to be addressed.  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