共查询到20条相似文献,搜索用时 15 毫秒
1.
Hiro Takahashi Takeshi Nemoto Teruhiko Yoshida Hiroyuki Honda Tadashi Hasegawa 《BMC bioinformatics》2006,7(1):399
Background
Recent advances in genome technologies have provided an excellent opportunity to determine the complete biological characteristics of neoplastic tissues, resulting in improved diagnosis and selection of treatment. To accomplish this objective, it is important to establish a sophisticated algorithm that can deal with large quantities of data such as gene expression profiles obtained by DNA microarray analysis. 相似文献2.
Background
Anaemia is a frequent complication of infection with the human immunodeficiency virus (HIV) and may have multiple causes. The objective of this study was to find out if blood haemoglobin measurement could be used as an indicator for the progression of HIV/AIDS in resource-limited setting. 相似文献3.
Aims
Accurate computed tomography (CT)-based reconstruction of coronary morphometry (diameters, length, bifurcation angles) is important for construction of patient-specific models to aid diagnosis and therapy. The objective of this study is to validate the accuracy of patient coronary artery lumen area obtained from CT images based on intravascular ultrasound (IVUS).Methods and Results
Morphometric data of 5 patient CT scans with 11 arteries from IVUS were reconstructed including the lumen cross sectional area (CSA), diameter and length. The volumetric data from CT images were analyzed at sub-pixel accuracy to obtain accurate vessel center lines and CSA. A new center line extraction approach was used where an initial estimated skeleton in discrete value was obtained using a traditional thinning algorithm. The CSA was determined directly without any circular shape assumptions to provide accurate reconstruction of stenosis. The root-mean-square error (RMSE) for CSA and diameter were 16.2% and 9.5% respectively.Conclusions
The image segmentation and CSA extraction algorithm for reconstruction of coronary arteries proved to be accurate for determination of vessel lumen area. This approach provides fundamental morphometric data for patient-specific models to diagnose and treat coronary artery disease. 相似文献4.
Introduction
Previous studies have shown that traditional risk factors such as hypercholesterolemia and hypertension account for only a small proportion of the dramatically increased risk of atherosclerotic coronary artery disease (CAD) in systemic lupus erythematosus (SLE). However, in these studies, exposure to risk factors was measured only at baseline. In this study, our objective was to compare measures of cumulative exposure with remote and recent values for each of total cholesterol (TC), systolic (SBP), and diastolic (DBP) blood pressure in terms of ability to quantify risk of atherosclerotic CAD in patients with SLE. 相似文献5.
Mandana Nikpour Dafna D Gladman Dominique Ibanez Paula J Harvey Murray B Urowitz 《Arthritis research & therapy》2010,12(3):R125
Introduction
Total cholesterol (TC) and blood pressure (BP) are likely to take a dynamic course over time in patients with systemic lupus erythematosus (SLE). This would have important implications in terms of using single-point-in-time measurements of these variables to assess coronary artery disease (CAD) risk. The objective of this study was to describe and quantify variability over time of TC and BP among patients with SLE and to determine their correlates. 相似文献6.
I-TASSER server for protein 3D structure prediction 总被引:5,自引:0,他引:5
Yang Zhang 《BMC bioinformatics》2008,9(1):40
Background
Prediction of 3-dimensional protein structures from amino acid sequences represents one of the most important problems in computational structural biology. The community-wide Critical Assessment of Structure Prediction (CASP) experiments have been designed to obtain an objective assessment of the state-of-the-art of the field, where I-TASSER was ranked as the best method in the server section of the recent 7th CASP experiment. Our laboratory has since then received numerous requests about the public availability of the I-TASSER algorithm and the usage of the I-TASSER predictions. 相似文献7.
Alexander Mellmann Thomas Weniger Christoph Berssenbrügge Jörg Rothgänger Michael Sammeth Jens Stoye Dag Harmsen 《BMC microbiology》2007,7(1):98
Background
For typing of Staphylococcus aureus, DNA sequencing of the repeat region of the protein A (spa) gene is a well established discriminatory method for outbreak investigations. Recently, it was hypothesized that this region also reflects long-term epidemiology. However, no automated and objective algorithm existed to cluster different repeat regions. In this study, the Based Upon Repeat Pattern (BURP) implementation that is a heuristic variant of the newly described EDSI algorithm was investigated to infer the clonal relatedness of different spa types. 相似文献8.
Matti Nykter Tommi Aho Miika Ahdesmäki Pekka Ruusuvuori Antti Lehmussola Olli Yli-Harja 《BMC bioinformatics》2006,7(1):349-17
Background
Microarray technologies have become common tools in biological research. As a result, a need for effective computational methods for data analysis has emerged. Numerous different algorithms have been proposed for analyzing the data. However, an objective evaluation of the proposed algorithms is not possible due to the lack of biological ground truth information. To overcome this fundamental problem, the use of simulated microarray data for algorithm validation has been proposed. 相似文献9.
Anna Lúcia Mourad Henrique Luvison Gomes da Silva Júlio César Batista Nogueira 《The International Journal of Life Cycle Assessment》2012,17(2):176-183
Purpose
Chain efficiency is currently a key issue for evaluating the sustainability of products and processes. Thus, the objective of this study was to evaluate how the overall efficiency process improvement carried out in the upstream manufacturing chain of LPB (Liquid Packaging Board) has affected the environmental profile over the last 10 years. 相似文献10.
Background
Elevated transient ischemic ST segment episodes in the ambulatory electrocardiographic (AECG) records appear generally in patients with transmural ischemia (e. g. Prinzmetal's angina) while depressed ischemic episodes appear in patients with subendocardial ischemia (e. g. unstable or stable angina). Huge amount of AECG data necessitates automatic methods for analysis. We present an algorithm which determines type of transient ischemic episodes in the leads of records (elevations/depressions) and classifies AECG records according to type of ischemic heart disease (Prinzmetal's angina; coronary artery diseases excluding patients with Prinzmetal's angina; other heart diseases).Methods
The algorithm was developed using 24-hour AECG records of the Long Term ST Database (LTST DB). The algorithm robustly generates ST segment level function in each AECG lead of the records, and tracks time varying non-ischemic ST segment changes such as slow drifts and axis shifts to construct the ST segment reference function. The ST segment reference function is then subtracted from the ST segment level function to obtain the ST segment deviation function. Using the third statistical moment of the histogram of the ST segment deviation function, the algorithm determines deflections of leads according to type of ischemic episodes present (elevations, depressions), and then classifies records according to type of ischemic heart disease.Results
Using 74 records of the LTST DB (containing elevated or depressed ischemic episodes, mixed ischemic episodes, or no episodes), the algorithm correctly determined deflections of the majority of the leads of the records and correctly classified majority of the records with Prinzmetal's angina into the Prinzmetal's angina category (7 out of 8); majority of the records with other coronary artery diseases into the coronary artery diseases excluding patients with Prinzmetal's angina category (47 out of 55); and correctly classified one out of 11 records with other heart diseases into the other heart diseases category.Conclusions
The developed algorithm is suitable for processing long AECG data, efficient, and correctly classified the majority of records of the LTST DB according to type of transient ischemic heart disease. 相似文献11.
Dirk Repsilber Sabine Kern Anna Telaar Gerhard Walzl Gillian F Black Joachim Selbig Shreemanta K Parida Stefan HE Kaufmann Marc Jacobsen 《BMC bioinformatics》2010,11(1):27
Background
For heterogeneous tissues, such as blood, measurements of gene expression are confounded by relative proportions of cell types involved. Conclusions have to rely on estimation of gene expression signals for homogeneous cell populations, e.g. by applying micro-dissection, fluorescence activated cell sorting, or in-silico deconfounding. We studied feasibility and validity of a non-negative matrix decomposition algorithm using experimental gene expression data for blood and sorted cells from the same donor samples. Our objective was to optimize the algorithm regarding detection of differentially expressed genes and to enable its use for classification in the difficult scenario of reversely regulated genes. This would be of importance for the identification of candidate biomarkers in heterogeneous tissues. 相似文献12.
13.
Background
Laser bio-stimulation is a well-established procedure in Medical Acupuncture. Nevertheless there is still a confusion as to whether it works or the effect is just placebo. Although a plethora of scientific papers published, showing positive clinical results, there is still a lack of objective scientific proofs about the bio-stimulation effect of lasers used in Acupuncture. The objective of this work was to design and build a body surface electrode and an amplifier for biopotential recording from acupuncture points, considered here as small localized bio-sources (SLB). The design is aimed for studying SLB potentials provoked by laser stimulus, in search for objective proofs of the bio-stimulation effect of lasers used in Medical Acupuncture. 相似文献14.
Plazak W Gryga K Dziedzic H Tomkiewicz-Pajak L Konieczynska M Podolec P Musial J 《Arthritis research & therapy》2011,13(4):R117
Introduction
Mortality in systemic lupus erythematosus (SLE) patients is influenced by an increased occurrence of severe cardiovascular complications. Statins have been proven to protect a wide spectrum of SLE patients from these complications. This study was conducted to determine the possible efficacy of atorvastatin in SLE patients as assessed by multi-detector computed tomography (MDCT)-based coronary calcium scoring and single photon emission computed tomography (SPECT) of the myocardium. 相似文献15.
Core Hunter: an algorithm for sampling genetic resources based on multiple genetic measures 总被引:1,自引:0,他引:1
Chris Thachuk José Crossa Jorge Franco Susanne Dreisigacker Marilyn Warburton Guy F Davenport 《BMC bioinformatics》2009,10(1):243
Background
Existing algorithms and methods for forming diverse core subsets currently address either allele representativeness (breeder's preference) or allele richness (taxonomist's preference). The main objective of this paper is to propose a powerful yet flexible algorithm capable of selecting core subsets that have high average genetic distance between accessions, or rich genetic diversity overall, or a combination of both. 相似文献16.
Laurence M O'Connor-Read Jerome A Davidson Benjamin M Davies Michael G Matthews Paul Smirthwaite 《Biomedical engineering online》2008,7(1):3
Background
The dynamic compression screw is a plate and screws implant used to treat fractures of the distal femur. The Biomet Matthews Nail is a new retrograde intramedullary nail designed as an alternative surgical option to treat these fractures. The objective of this study was to assess the comparative endurance of both devices. 相似文献17.
Patel SM McLeod CJ Friedman PA Liu X Asirvatham SJ 《Indian pacing and electrophysiology journal》2011,11(2):43-49
Background and objectives
While radiofrequency ablation catheter ablation of accessory pathways is generally safe and effective, anatomic variants can cause considerable challenges in effecting cure. Our objective was to use an unusual case where coronary sinus was absent and arterial venous fistula was present and a left-sided pathway required mapping and ablation to develop a framework to approach difficult cases.Method
A detailed literature search and review of contemporary cardiac embryology was undertaken to attempt and to explain a common developmental anomaly. Adjunctive approaches during the ablation procedure, including intracardiac ultrasound, were used to guide mapping and ablation despite the lack of coronary sinus access.Results
The accessory pathway was successfully ablated using a transseptal approach and intracardiac ultrasound guided mapping of the mitral annulus. A potential common mechanism to explain the apparently disparate anatomic variants in this patient was formulated.Conclusions
Cardiac conduction development is complex and accessory pathway conduction may occur in the setting of arteriovenous anomalies thus providing insights as to the cause of WPW syndrome. Successful mapping and targeted ablation of left-sided pathways may be accomplished even when coronary sinus access is not possible. 相似文献18.
Thomas Frauenfelder Evangelos Boutsianis Thomas Schertler Lars Husmann Sebastian Leschka Dimos Poulikakos Borut Marincek Hatem Alkadhi 《Biomedical engineering online》2007,6(1):35
Purpose
Coronary artery bypass graft (CABG) surgery represents the standard treatment of advanced coronary artery disease. Two major types of anastomosis exist to connect the graft to the coronary artery, i.e., by using an end-to-side or a side-to-side anastomosis. There is still controversy because of the differences in the patency rates of the two types of anastomosis. The purpose of this paper is to non-invasively quantify hemodynamic parameters, such as mass flow and wall shear stress (WSS), in end-to-side and side-to-side anastomoses of patients with CABG using computational fluid dynamics (CFD). 相似文献19.
Manathip Osiri Jeerapat Wongchinsri Sitthichai Ukritchon Punchong Hanvivadhanakul Nuntana Kasitanon Boonjing Siripaitoon 《Arthritis research & therapy》2009,11(4):R129-8
Introduction
The Health Assessment Questionnaire Disability Index (HAQ-DI) is a commonly used instrument to assess functional status of patients with rheumatoid arthritis (RA). Translations and adaptations of the HAQ-DI have been carried out for use with RA patients in several countries. The objective of this study was to evaluate the psychometric properties of the Thai version of the HAQ-DI (Thai HAQ) in Thai patients with RA. 相似文献20.
Ji-Rui Wang Yu-Ming Wei Xiang-Yu Long Ze-Hong Yan Eviatar Nevo Bernard R Baum You-Liang Zheng 《BMC evolutionary biology》2008,8(1):91