Objective To systematically review the effectiveness and safety of power chain vs. nickel titanium coil springs in closing dental extraction space. Methods Databases including PubMed, EMbase, The Cochrane Library, Chinese Biomedicine Literature Database, Chinese Scientific Journals Full-text Database, and Chinese Journal Full-text Database were searched to collect the randomized controlled trials (RCTs) on comparing power chain with nickel titanium coil springs published before February 2012. Two reviewers independently screened literature, extracted data and assessed the quality of the included studies. Then meta-analysis was conducted using RevMan 5.0 software. Results A total of 4 RCTs involving 122 patients were included. The results of meta-analyses showed that there was a significant difference in the rate of space closure between the two groups (MD=0.30 mm per month, 95%CI 0.17 to 0.44, Plt;0.000 1); The results of subgroup analyses indicated that, both high-quality trials (MD=0.20, 95%CI 0.07 to 0.34, P=0.003) and low quality trials (MD=0.40, 95%CI 0.30 to 0.50, Plt;0.000 01) showed no significant difference in the rate of space closure. Conclusion Current clinical evidence indicates nickel titanium coil spring is superior to power chain in the rate of space closure, but its long-term effect still needs to be proved by more large-scale RCTs.
ObjectiveTo study the effect of chemical extraction of allogeneic tendon and allogeneic chondrocytes for reconstruction of anterior labrum of shoulder joint in rabbits.MethodsThe body weight of 45 adult New Zealand white rabbits ranged from 2.5 to 3.0 kg. The Achilles tendons of 15 rabbits were taken and the allogeneic tendons were prepared by chemical extraction with antigen inactivation. The extracted tendons were compared with untreated tendons by HE and Masson stainings. Chondrocytes were isolated and cultured by trypsin method and identified by immunohistochemical staining of collagen type Ⅱ. The remaining 30 rabbits were used to prepare the model of anterior labrum defect of shoulder joint. After the allogeneic tendon was transplanted to the damaged labrum, the rabbits was randomly divided into two groups (15 in each group). In group A, the allogeneic chondrocytes were injected into the joint immediately after transplantation, while in group B, no treatment was made. At 4, 6, and 8 weeks after operation, 5 transplanted tendons of each group were taken. After general observation, HE staining was used to observe the number of nuclei, Masson staining was used to observe the expression of collagen fibers in muscle fiber tissues, and AB staining was used to detect the glycosaminoglycan level after transplantation, to evaluate the cell growth in the tissues of the two groups of allogeneic tendon.ResultsBy HE and Masson stainings, the allogeneic tendon antigen prepared by chemical extraction method was inactivated and the fibrous tissue structure was intact; collagen type Ⅱ immunohisto-chemistry staining showed that the cultured cells were chondrocytes. After tendon transplantation, the content of glycosaminoglycan in group A was significantly higher than that in group B (P<0.05). At 6 weeks after operation, HE staining showed that the nuclear in tendon tissue of group A was significantly more than that of group B (t=20.043, P=0.000). Masson staining showed that the number of nuclei in tendon tissue of group A was significantly increased, the muscle fibers and collagen fibers were interlaced, the tissue structure was more compact, and the tendon tissue was mainly blue stained; while the number of nuclei in group B was less, mainly collagen fibers of the original graft.ConclusionThe allogeneic tendon inactivated by chemical extraction can be used to reconstruct the defect of anterior labrum of shoulder joint in rabbits, and the combination of allogeneic chondrocytes can promote the healing of tendon transplantation.
Objective To investigate the effects of phacoemulsification on macula in diabetics． Methods Thirty eyes of cataract in diabetics were chosen randomly for measurement of the thickness of fovea of retina using OCT before phacoemulsification and 1 month after surgery ． The other eyes in these patients and 30 eyes of cataract in nondiabetic pati ents with phacoemulsification were as control． Results In 30 eyes of diabetics with phacoemulsification, the mean fovea thickness were (148．5plusmn;27．7) mu;m preoperatively and (219．4plusmn;68．23) mu;m postoperatively, and the difference was significant (Plt;0．05)． In 30 eyes of diabetics without surgery, the mean foveal thickness were (147.4plusmn;27.5) mu;m preoperatively and (148.2plusmn;27.3) mu;m postoperatively and the difference was not significant (Pgt;0．05)． In 30 eyes of cataract in nondiabetic patients, the mean fovea thickness were (142．37plusmn;12．7) mu;m preoperatively and (151．9plusmn;23．7) mu;m postoperatively and the difference was not significant (Pgt;0．05)． In 30 eyes of diabetic s with phacoemulsification, 11 eyes had new macula edema after surgery and 3 eye s had significant retinal thickening． In 6 eyes with macular edema before surgery, the macular edema were aggravated in 3 eyes after surgery． The macular stru ctural changes were not found in two control groups． Conclusion The thickness of retina is inreased after phacoemulsification in deabetics,and morbidity and its severity of postopevative macular edema are increas ed as well． (Chin J Ocul Fundus Dis, 2001,17:175-177)
Feature extraction is a very crucial step in P300-based brain-computer interface (BCI) and independent component analysis (ICA) is a suitable P300 feature extraction method. But at present the convergence performance of the general ICA iteration methods are not very satisfactory. In this paper, a method based on quantum particle swarm optimizer (QPSO) algorithm and ICA technique is put forward for P300 extraction. In this method, quantum computing is used to impel ICA iteration to globally converge faster. It achieved the purpose of extracting P300 rapidly and efficiently. The method was tested on two public datasets of BCI Competition Ⅱ and Ⅲ, and a simple linear classifier was employed to classify the extracted P300 features. The recognition accuracy reached 94.4% with 15 times averaged. The results showed that the proposed method could extract P300 rapidly and the extraction effect did not reduce. It provides an experimental basis for further study of real-time BCI system.
In order to solve the saturation distortion phenomenon of R component in fingertip video image, this paper proposes an iterative threshold segmentation algorithm, which adaptively generates the region to be detected for the R component, and extracts the human pulse signal by calculating the gray mean value of the region to be detected. The original pulse signal has baseline drift and high frequency noise. Combining with the characteristics of pulse signal, a zero phase digital filter is designed to filter out noise interference. Fingertip video images are collected on different smartphones, and the region to be detected is extracted by the algorithm proposed in this paper. Considering that the fingertip’s pressure will be different during each measurement, this paper makes a comparative analysis of pulse signals extracted under different pressures. In order to verify the accuracy of the algorithm proposed in this paper in heart rate detection, a comparative experiment of heart rate detection was conducted. The results show that the algorithm proposed in this paper can accurately extract human heart rate information and has certain portability, which provides certain theoretical help for further development of physiological monitoring application on smartphone platform.
The data collection form is a bridge in-between the original studies and the final systematic reviews. It’s the basis for data analyses, directly related to the results and conclusions of systematic reviews, and plays an important role in systematic reviews. There are strict requirements of data collection forms in making Cochrane systematic reviews. In this article, the authors introduce their experiences regarding to the design of data collection form.
Systematic reviews can provide important evidence support for clinical practice and health decision-making. In this process, literature screening and data extraction are extensively time-consuming procedures. Natural language processing (NLP), as one of the research directions of computer science and artificial intelligence, can accelerate the process of literature screening and data extraction in systematic reviews. This paper introduced the requirements of systematic reviews for rapid literature screening and data extraction, the development of NLP and types of machine learning; and systematically collated the NLP tools for the title and abstract screening, full-text screening and data extraction in systematic reviews; and discussed the problems in the application of NLP tools in the field of systematic reviews and proposed a prospect for its future development.
Objective To systematically review the effect of discontinuous warfarin on the risk of postoperative bleeding complications after tooth extractions. Methods PubMed, EMbase, The Cochrane Library (Issue 9, 2016), CNKI, VIP, WanFang Data, China Food and Drug Administration and the ADR supervision system of FDA were electronically searched to collect randomized controlled trials (RCTs) and cohort studies about the effect of discontinuous warfarin on risk of postoperative bleeding complications after tooth extractions in patients until September 30th, 2016. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed using RevMan 5.3 software. Results A total of 8 studies were included, involving 3 RCTs and 5 cohort studies. The results of meta-analysis showed that: there was no significant difference between the discontinuous or reduced warfarin group and the continuous warfarin group (RCTs: RR=0.86, 95%CI 0.49 to 1.51,P=0.60; cohort studies: RR=0.67, 95%CI 0.45 to 1.01,P=0.06). Conclusions Current evidence indicates that there is no statistically significant correlation between whether discontinuous warfarin and the risk of postoperative bleeding complications after tooth extractions. Due to the limited quantity and quality of included studies, the above conclusions are needed to be further verified by more high quality studies.
Image feature extraction is an important part of image processing and it is an important field of research and application of image processing technology. Uygur medicine is one of Chinese traditional medicine and researchers pay more attention to it. But large amounts of Uygur medicine data have not been fully utilized. In this study, we extracted the image color histogram feature of herbal and zooid medicine of Xinjiang Uygur. First, we did preprocessing, including image color enhancement, size normalizition and color space transformation. Then we extracted color histogram feature and analyzed them with statistical method. And finally, we evaluated the classification ability of features by Bayes discriminant analysis. Experimental results showed that high accuracy for Uygur medicine image classification was obtained by using color histogram feature. This study would have a certain help for the content-based medical image retrieval for Xinjiang Uygur medicine.
Femtosecond laser small incision lenticule extraction (SMILE) with different residual stromal thicknesses (RST) is set to investigate its effect on corneal biomechanical properties of rabbits in vivo. In this study, 24 healthy adult Japanese rabbits were randomly divided into group A and B. The RST of group A was set 30% of the corneal central thickness (CCT), and the RST of group B was 50% of the CCT. The thickness of the corneal cap in both groups was set one third of CCT. Corneal visualization Scheimpflug technology (Corvis ST) and Pentacam three-dimensional anterior segment analyzer were used to determine corneal biomechanical and morphological parameters before surgery, and 1 week, 1 month and 3 months after surgery. Pearson correlation analysis was used to analyze factors affecting corneal biomechanical parameters after SMILE. The results showed that the corneal stiffness of group A was significantly higher than that of group B at 1 week and 1 month after surgery, and most biomechanical parameters returned to preoperative levels at 3 months postoperatively. The results of correlation analysis showed that postoperative CCT and RST were the main factors affecting corneal biomechanical parameters after SMILE. There was no significant difference in corneal posterior surface height (PE) between 3 months after surgery and before surgery in both two groups. It indicates that although the ability to resist deformation of cornea decreases in SMILE with thicker corneal cap and less RST, there is no tendency to keratoconus, which may be related to the preservation of more anterior stromal layer.