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21.
《The Knee》2021
BackgroundAs knee osteotomy surgery becomes increasingly accessible, more patients may turn to the Internet for information. This study examined the source, quality, content and readability of online information regarding osteotomy around the knee.MethodsThe first 70 websites returned by the top four search engines were identified using the key words: “knee osteotomy” and “high tibial osteotomy.” The websites were categorised by type and assessed using the DISCERN score, Journal of the American Medical Association (JAMA) benchmark criteria and a novel Knee Osteotomy-Specific Score (KOSS). The presence of the Health On the Net (HON) code accreditation seal was noted. Readability of each website was assessed using eight readability formulae. The mean reading grade level (RGL) was compared to the 6th and 8th grade reading levels. The mean RGL of each category was also compared.ResultsOf the 45 unique websites analysed, the majority were Physician (33%) and Journal websites (31%). The mean DISCERN score was 36.7 (±8.9) which is classified as ‘poor.’ The mean JAMA benchmark criteria score was 2.04 (±1.5) and Physician websites were most likely to be scored zero. The mean KOSS was 15.4 (±5.7). The highest scoring website was a Commercial site but, overall, Journal category sites provided the best quality information. Websites that bore the HONcode seal obtained higher DISCERN, JAMA benchmark criteria and Knee Osteotomy - Specific Scores.The cumulative mean RGL was 13.2 (±2.2) which exceeded the 6th grade level by an average of 7.2 grade levels and the 8th grade level by an average of 5.2 grade levels. No website (0%) was written at or below either the 6th or the 8th grade reading levels. The mean Flesch Reading Ease Score of all websites was 41.13 (±14.7) which is classified as ‘difficult.’ Journal websites had the highest RGL.ConclusionThe information available online regarding osteotomy around the knee varies tremendously in quality and completeness. Physician sites predominate, but these were among the lowest scoring of all websites. Even where high quality information is available, it is set at too high a level to be easily understood.Level of evidenceSurvey of materials – Internet. 相似文献
22.
Objective
With the non-stop increases in medical treatment fees, the economic survival of a hospital in Taiwan relies on the reimbursements received from the Bureau of National Health Insurance, which in turn depend on the accuracy and completeness of the content of the discharge summaries as well as the correctness of their International Classification of Diseases (ICD) codes. The purpose of this research is to enforce the entire disease classification framework by supporting disease classification specialists in the coding process.Methodology
This study developed an ICD code advisory system (ICD-AS) that performed knowledge discovery from discharge summaries and suggested ICD codes. Natural language processing and information retrieval techniques based on Zipf's Law were applied to process the content of discharge summaries, and fuzzy formal concept analysis was used to analyze and represent the relationships between the medical terms identified by MeSH. In addition, a certainty factor used as reference during the coding process was calculated to account for uncertainty and strengthen the credibility of the outcome.Results
Two sets of 360 and 2579 textual discharge summaries of patients suffering from cerebrovascular disease was processed to build up ICD-AS and to evaluate the prediction performance. A number of experiments were conducted to investigate the impact of system parameters on accuracy and compare the proposed model to traditional classification techniques including linear-kernel support vector machines. The comparison results showed that the proposed system achieves the better overall performance in terms of several measures. In addition, some useful implication rules were obtained, which improve comprehension of the field of cerebrovascular disease and give insights to the relationships between relevant medical terms.Conclusion
Our system contributes valuable guidance to disease classification specialists in the process of coding discharge summaries, which consequently brings benefits in aspects of patient, hospital, and healthcare system. 相似文献23.
The adoption of ITs by medical organisations makes possible the compilation of large amounts of healthcare data, which are quite often needed to be released to third parties for research or business purposes. Many of this data are of sensitive nature, because they may include patient-related documents such as electronic healthcare records. In order to protect the privacy of individuals, several legislations on healthcare data management, which state the kind of information that should be protected, have been defined. Traditionally, to meet with current legislations, a manual redaction process is applied to patient-related documents in order to remove or black-out sensitive terms. This process is costly and time-consuming and has the undesired side effect of severely reducing the utility of the released content. Automatic methods available in the literature usually propose ad-hoc solutions that are limited to protect specific types of structured information (e.g. e-mail addresses, social security numbers, etc.); as a result, they are hardly applicable to the sensitive entities stated in current regulations that do not present those structural regularities (e.g. diseases, symptoms, treatments, etc.). To tackle these limitations, in this paper we propose an automatic sanitisation method for textual medical documents (e.g. electronic healthcare records) that is able to protect, regardless of their structure, sensitive entities (e.g. diseases) and also those semantically related terms (e.g. symptoms) that may disclose the former ones. Contrary to redaction schemes based on term removal, our approach improves the utility of the protected output by replacing sensitive terms with appropriate generalisations retrieved from several medical and general-purpose knowledge bases. Experiments conducted on highly sensitive documents and in coherency with current regulations on healthcare data privacy show promising results in terms of the practical privacy and utility of the protected output. 相似文献
24.
目的 探讨蒙特卡罗N粒子运输法(MCNP)模拟计算的可行性.方法 用百分深度剂量(PDD)分布及标准峰值散射因子(NPSP),比较水模体计算值和实际测量及报告值之间的差异.结果 在10 cm×10 cm射野时,测量值和计算值之间差异无统计学意义(t=-0.41,P>0.05),而在5 cm×5 cm及12 cm×12 cm时,测量值与计算值之间差异有统计学意义(t=7.2、-4.6,P<0.05).计算值和报告值之间符合良好,差异无统计学意义(t=-1.906,P>0.05).同一射野最大剂量点下百分深度剂量随深度增大而减少,同一深度处百分深度剂量随射野增大而增大;同一深度处射野中心轴上的剂量最高,向射野边缘剂量逐渐减少.结论 利用蒙特卡罗MCNP可以建立一组准确和全面的百分深度剂量及标准峰值散射因子参数,为放疗质量保证和质量控制提供依据.Abstract: Objective To discuss the feasibility of Monte Carlo N-particle transport code(MCNP)simulated calculation.Methods The calculation in water phantom was contrasted with the practical measurements and the reported values using the percent depth dose(PDD)curve and normal peak scatter factor.Results There Was no significant difference between calculated and measured results in the 10 cm×10 cm field(t=-0.41,P>0.05),however,there were significant differences in the 5 cm×5 cm field(t=7.2,P<0.05)and in the 12 cm×12 cm field(t=-4.6,P<0.05).There was no significant difierence between the calculated results and the reported values(t=-1.91,P>0.05).In the same radiation field,the PDD decreased as the depth increased,but increased as the size of the radiation field increased at the same depth.PDD and normal peak scatter factor were both important parameters for calculation of prescribed dose.Conclusions It is possible to establish a set of accurate and comprehensive percent depth doses and normal peak scatter factor parameters so as to provide the basis of clinical use, quality assurance and quality control for radiotherapy. 相似文献
25.
Distributed population codes are ubiquitous in the brain and pose a challenge to downstream neurons that must learn an appropriate readout. Here we explore the possibility that this learning problem is simplified through inductive biases implemented by stimulus-independent noise correlations that constrain learning to task-relevant dimensions. We test this idea in a set of neural networks that learn to perform a perceptual discrimination task. Correlations among similarly tuned units were manipulated independently of an overall population signal-to-noise ratio to test how the format of stored information affects learning. Higher noise correlations among similarly tuned units led to faster and more robust learning, favoring homogenous weights assigned to neurons within a functionally similar pool, and could emerge through Hebbian learning. When multiple discriminations were learned simultaneously, noise correlations across relevant feature dimensions sped learning, whereas those across irrelevant feature dimensions slowed it. Our results complement the existing theory on noise correlations by demonstrating that when such correlations are produced without significant degradation of the signal-to-noise ratio, they can improve the speed of readout learning by constraining it to appropriate dimensions.SIGNIFICANCE STATEMENT Positive noise correlations between similarly tuned neurons theoretically reduce the representational capacity of the brain, yet they are commonly observed, emerge dynamically in complex tasks, and persist even in well-trained animals. Here we show that such correlations, when embedded in a neural population with a fixed signal-to-noise ratio, can improve the speed and robustness with which an appropriate readout is learned. In a simple discrimination task such correlations can emerge naturally through Hebbian learning. In more complex tasks that require multiple discriminations, correlations between neurons that similarly encode the task-relevant feature improve learning by constraining it to the appropriate task dimension. 相似文献
26.
27.
Simone Corrêa Rosa Jefferson Lessa Soares de Macedo Lucas Ribeiro Canedo Luiz Augusto Casulari 《Surgery for obesity and related diseases》2019,15(3):447-455
BackgroundObesity is a major health risk factor associated with medical complications, such as cardiovascular disease, that may compromise outcomes. Furthermore, obesity may lead to difficulties in daily life, altering the quality of life and generating psychological disorders such as devalued self-image and depression.ObjectivesThis study evaluated the quality of life and predictive factors of postoperative complications in patients who underwent abdominoplasty after Roux-en-Y gastric bypass.SettingBariatric and postbariatric center, North Wing Regional Hospital, Brasília, Brazil.MethodsData were analyzed from a prospective registry of postbariatric patients who underwent abdominoplasty from January 2011 to December 2016. Variables examined included age, sex, body mass index (BMI), complications, and comorbidities. Multivariate analyses were performed to assess outcome measures. The quality-of-life assessment was measured with the Moorehead-Ardelt quality-of-life questionnaire.ResultsOne hundred and seven postbariatric patients were included. The mean age of the patients was 41 years. BMI at the time of abdominoplasty (current BMI) was 27.6 ± 3.7 kg/m2, and the average weight loss before abdominoplasty was 47.7 ± 17.3 kg. Pre-weight loss BMI (max BMI) was 45.5 ± 7.6 kg/m2, and ?BMI was 18.6 ± 9.3 kg/m2. The overall rate of complications was 23.4%. Among the studied factors in the multivariate analysis, amount of removed tissue in the abdomen >2000 g, ?BMI >20 kg/m2, and age >40 years significantly increased the rates of postoperative complications. In our study, abdominoplasty improved the quality of life of patients (mean quality-of-life scores, 2.1 ± 0.9).ConclusionThe amount of removed tissue in the abdomen, ?BMI >20 kg/m2, and age >40 years led to significantly more complications in patients undergoing abdominoplasty after gastroplasty. In addition, this study demonstrated that abdominoplasty should be proposed to patients with massive weight loss to improve quality of life. 相似文献
28.
E.C. Ataide S.R. Perales M.G. Silva F.C. Filho A.C. Sparapani P.F. Latuf Filho R.S.B. Stucchi J. Vassallo C.A.F. Escanhoela I.F.S.F. Boin 《Transplantation proceedings》2017,49(4):858-862
Background
Hepatocellular carcinoma (HCC) is the 6th leading cause of cancer worldwide. Its recurrence ranges from 6% to 26%. In the literature, many factors are associated with higher risk of recurrence, without a clear definition of the best method that could predict this highly lethal event.Objective
The aim of this study was to evaluate the immunoexpression of immunohistochemical markers: HSP70, glypican 3, glutamine synthetase, and beta-catenin, as well as studying their association with tumor characteristics and prognosis of patients undergoing liver transplantation for HCC.Methods
We studied 90 patients who underwent liver transplantation from 1998 to 2012. Afterwards we evaluated factors related to survival, tumor recurrence, and the correlation of expression of the immunohistochemical markers.Results
Immunohistochemical marker glutamine synthetase showed a positive trend toward better survival. HSP70-positive patients had a higher prevalence of histologic grade III. Patients with positive glypican 3 showed larger lesions and a higher number with AFP >200 ng/mL. Patients with positive beta-catenin showed larger nodules and more with histologic grade III. The association between beta-catenin and glypican 3 showed positive association with larger nodules.Conclusions
Most of the markers studied had a correlation with at least one of the variables studied, confirming our hypothesis that these markers can indeed assist in assessing the prognosis of patients undergoing liver transplantation for HCC. 相似文献29.
Developed for radionuclide standardization using liquid scintillation, the Triple to Double Coincidence Ratio (TDCR) method is applied using coincidence counting obtained with a specific three-photomultiplier system. For activity determination, a statistical model of light emission is classically used to establish a relation between the detection efficiency and the experimental TDCR value. At LNE-LNHB, a stochastic approach of the TDCR modeling was developed using the Monte Carlo code Geant4. The interest of this TDCR-Geant4 model is the possibility to simulate the propagation of optical photons from their creation in the scintillation vial to the production of photoelectrons in photomultipliers.As an alternative to the use of radionuclide sources, first TDCR measurements are presented using a miniature x-ray tube closely coupled to the scintillation vial. The objective of this new set-up was to enable low-energy depositions (lower than 20 keV) in liquid scintillator in order to study the influence of both time and geometrical dependence between PMTs already observed with radioactive sources. As for the statistical TDCR model, the non-linearity of light emission is implemented in the TDCR-Geant4 model using the Birks formula which depends on the kB factor and the scintillation yield. Measurements performed with the x-ray tube are extended to the assessment of these parameters and they are tested afterwards in the TDCR-Geant4 model for activity measurements of 3H. 相似文献
30.
Victoria A. Chang Dawn M. Meyer Brett C. Meyer 《Journal of stroke and cerebrovascular diseases》2019,28(1):163-166