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1.
Diagn Interv Imaging ; 101(9): 599-610, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32033913

RESUMO

PURPOSE: The purpose of this study was to develop predictive models to classify osteoporosis, osteopenia and normal patients using radiomics and machine learning approaches. MATERIALS AND METHODS: A total of 147 patients were included in this retrospective single-center study. There were 12 men and 135 women with a mean age of 56.88±10.6 (SD) years (range: 28-87 years). For each patient, seven regions including four lumbar and three femoral including trochanteric, intertrochanteric and neck were segmented on bone mineral densitometry images and 54 texture features were extracted from the regions. The performance of four feature selection methods, including classifier attribute evaluation (CLAE), one rule attribute evaluation (ORAE), gain ratio attribute evaluation (GRAE) and principal components analysis (PRCA) along with four classification methods, including random forest (RF), random committee (RC), K-nearest neighbor (KN) and logit-boost (LB) were evaluated. Four classification categories, including osteopenia vs. normal, osteoporosis vs. normal, osteopenia vs. osteoporosis and osteoporosis+osteopenia vs. osteoporosis were examined for the defined seven regions. The classification model performances were evaluated using the area under the receiver operator characteristic curve (AUC). RESULTS: The AUC values ranged from 0.50 to 0.78. The combination of methods RF+CLAE, RF+ORAE and RC+ORAE yielded highest performance (AUC=0.78) in discriminating between osteoporosis and normal state in the trochanteric region. The combinations of RF+PRCA and LB+PRCA had the highest performance (AUC=0.76) in discriminating between osteoporosis and normal state in the neck region. CONCLUSION: The machine learning radiomic approach can be considered as a new method for bone mineral deficiency disease classification using bone mineral densitometry image features.


Assuntos
Doenças Ósseas Metabólicas , Aprendizado de Máquina , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minerais , Estudos Retrospectivos
2.
Iran J Ped Hematol Oncol ; 5(2): 93-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131348

RESUMO

BACKGROUND: Multiple transfusions in thalassemia patients may lead to antibody production against blood group antigens and hemolytic transfusion reaction might occur. In this study, antibody screening test was performed by tube and gel methods to determine the prevalence and specificity of alloantibodies in thalassemia patients. MATERIALS AND METHODS: In this cross-sectional study, overall of 100 thalassemia patients from Yazd thalassemia clinic were recruited from July to September 2013. Two blood samples with volume of 6 ml were collected from each patient for standard tube and gel method antibody screening tests and a questionnaire consisting of demographic, health and blood transfusion status was completed. RESULTS: Out of 100 cases, 54 were female (54%) and 46 male (46%). The patients' age mean was 14.97±7.91 years with 2 to 33 years age range. Only 4% (n=4) had developed alloantibodies. (One patient developed dual alloantibody (Anti-C and Anti-D) and three patients developed single alloantibody (Anti-K)).Gel method detected 4 patients with alloantibody but in two patients not detected by the standard tube method. CONCLUSION: The prevalence of RBC alloantibody production in this study was less than most previous studies. Anti-K was the most prevalent alloantibody in thalassemia patients in Yazd. It seems Rh and Kell blood group phenotyping in a newly diagnosed thalassemia patient and selection of matched blood for transfusion is very important.

3.
Iran J Ped Hematol Oncol ; 3(3): 119-24, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24575283

RESUMO

BACKGROUND: Increasing blood supply safety is one of the most important goals of blood services in the world. In this study, we reviewed the prevalence rate and the trends of three main infections in whole blood donations and strategies for improving blood safety in Yazd blood transfusion center, Iran. MATERIALS AND METHODS: In this cross sectional study, data on hepatitis B, C and HIV infection were extracted from Iranian Donor Database of blood donation from 2004 to 2010 in Yazd province. All donors with positive confirmatory test were included. The data was analyzed by SPSS software due to demographic factors. RESULTS: The prevalence rate of hepatitis B, C and HIV infection decreased during these years (From 0.37%, 0.14% and 0 percent in 2004 to 0.14%, 0.05% and 0 in 2010, respectively). Both hepatitis B and C infections were significantly more in first-time blood donors with BSc or BA educational level. The prevalence rate of hepatitis B was significantly higher in donors with less than 20 year-old and female donors. The prevalence rate of hepatitis C was higherin30-39 age group (P-value= 0.014). CONCLUSION: The results showed that the strategies used for improving blood safety were efficient. Increasing public knowledge on blood-borne infections and their routes of transmission, importance of donating blood only by healthy donors are necessary to have a safe blood supply in future.

4.
Acta Anaesthesiol Belg ; 62(1): 11-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21612140

RESUMO

The aim of this clinical case-control trial was to compare postoperative early jaundice and transient liver damage in patients receiving autologous or homologous blood transfusion in coronary artery bypass grafting (CABG) surgery. In this randomized clinical trial 40 patients scheduled for CABG were randomly allocated to ANH (Acute Normovolemic Hemodilution) group or control group. Both groups were compared in relation to bilirubin (total and direct), alanine transferase (ALT), aspartate transferase (AST) and alkaline phosphatase (ALP) in the first 24 hours. There was a significant difference in bilirubin (total and direct) change between groups (both p<0.00001). However, there were no changes in ALT, AST and ALP compared with baseline values, and there were no differences in the values between the two study groups. Our randomized, double blinded case control study suggested that patients receiving autologous blood (ANH group) following CABG had significantly lower bilirubin levels compared to patients who received homologous transfusion. However larger studies with more patients are needed to confirm the results.


Assuntos
Bilirrubina/sangue , Transfusão de Sangue , Ponte de Artéria Coronária , Hemodiluição , Fígado/enzimologia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Prospectivos
5.
Int J Immunogenet ; 35(6): 453-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19046304

RESUMO

One of the most fascinating areas of research within the field of histocompatibility at present time concerns an observation that a major human histocompatibility system, human leucocyte antigen (HLA), is deeply involved in the development of a great number of diseases. Major histocompatibility complex is the most polymorphic system in the genome of different species. Recognition of HLA alleles could be useful in transplantation and disease studies. Genetic construct of HLA DRB1 was studied in Iranian normal populations and patients with aplastic anaemia and Fanconi's disease. DNA was extracted from the whole blood of 466 normal, 35 aplastic anaemia and 10 Fanconi's individuals. Then DRB1 gene polymorphism was studied by polymerase chain reaction-sequence-specific primer method. The HLA DRB1 gene analysis showed increase of DRB1*07 in aplastic anaemia patients compared to normal population (P = 0.02). According to this study, the frequency of DRB1*07 in normal individuals was 8.3, and in aplastic anaemia patients, 15.7%. Additionally, the frequency of DRB1*04 in normal, aplastic anaemia and Fanconi's individuals was 10, 5.7 and 20%, respectively. Our results of investigation showed correlation between some HLA alleles with the studied diseases. We reported the frequency of various DR types in aplastic and Fanconi's patients. This study could imply the possible role of HLA-DRB1*07 in the incidence of aplastic anaemia. Moreover, the frequency of DRB1*04, DRB1*03 and DRB1*15 alleles showed intermediate correlation with Fanconi's anaemia.


Assuntos
Anemia Aplástica/genética , Síndrome de Fanconi/genética , Predisposição Genética para Doença , Antígenos HLA-DR/genética , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , Feminino , Frequência do Gene , Genótipo , Cadeias HLA-DRB1 , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Pak J Biol Sci ; 11(18): 2254-8, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19137836

RESUMO

The HPLC system separated completely isofavonoids such as daidzein (15.2 min) and genistein (17.3 min). Initially, the concentrations of major isoflavone Genistein and Daidzein in the tested soy milk were determined. Commercial soy milk samples were analyzed for isoflavones and two major isoflavones detected: genistein 25.86 (mg L(-1)) +/- 0.66 SD and daidzein 8.25 (mg L(-1)) +/- 1.13 SD. Concentrations of genistein in soy milk were higher than daidzein. The results obtained in this study can serve as a basis for estimating amount of soy milk can be consumed by people as related to its main isoflavone content.


Assuntos
Genisteína/análise , Isoflavonas/análise , Leite de Soja/química , Cromatografia Líquida de Alta Pressão/métodos , Irã (Geográfico) , Fitoestrógenos/análise
7.
Phys Rev Lett ; 97(7): 075501, 2006 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-17026242

RESUMO

We report that kink motion is a universal plastic deformation mode in all carbon nanotubes when being tensile loaded at high temperatures. The kink motion, observed inside a high-resolution transmission electron microscope, is reminiscent of dislocation motion in crystalline materials: namely, it dissociates and multiplies. The kinks are nucleated from vacancy creation and aggregation, and propagate in either a longitudinal or a spiral path along the nanotube walls. The kink motion is related to dislocation glide and climb influenced by external stress and high temperatures in carbon nanotubes.

8.
Iran J Allergy Asthma Immunol ; 2(1): 45-51, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17301356

RESUMO

Chronic granulomatous disease represents a group of inherited disorders of phagocytic system wherein recurrent infections are seen at different sites especially in the respiratory system. To determine the clinical spectrum of respiratory manifestations in chronic granulomatous disease patients, in this retrospective study, we used data from Iranian Primary Immunodeticiency Registry. The diagnosis was based upon WHO criteria for chronic granulomatous disease. We reviewed the records of 38 patients (26 males, 12 females), related to 33 families, 73% of whom were consanguineous. The median age at the time of the study was 12yrs (3 months-22 years). The median onset age of symptoms was 4 months (l month-12 years), and that of diagnostic age was 5 years (l month-20 years), with a diagnostic delay of 4.15 years, on an average. Sixty three percent of our patients had respiratory involvement in the course of their illness, including pneumonia (18 pts, 75%), tuberculosis (llpts, 46%), aspergillosis (3 pts, 12.5%), pulmonary abscess (3 pts, 12.5%), and bronchiectasis (1 pt, 4%). Only 4 of our patients presented with respiratory problems as their first manitestation. Lymph nodes were the first common site and the lungs were the second sites of involvement in chronic granulomatous disease patients; however, it is noteworthy that only in a few of our patients, it was the first manifestation of the disease. Thus special attention should be paid to the pulmonary complications while managing this disease.

9.
Appl Opt ; 36(15): 3439-43, 1997 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18253361

RESUMO

We present a new technique for measuring the intermodal beat length of a two-mode optical fiber. We formed a Fabry-Perot fiber cavity by depositing reflective mirrors on the fiber tips. As the fiber is stretched, two series of resonance peaks are observed. One series is due to the resonance of LP(01 q) modes and the other is due to the LP(11 q) modes. From the separation of resonance peaks as a function of cavity length, we deduce the intermodal beat length of the fiber. The measurement principle and the experimental confirmation are discussed.

10.
Opt Lett ; 21(16): 1211-3, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19876302

RESUMO

We experimentally demonstrate the operation of a low-birefringence (low-bi) nonlinear-optical loop mirror (NOLM) that has the advantages of low switching energy, tolerance to timing jitter, and cascadability. Because cascading two all-optical logic gates is an important step toward high-speed optical signal processing and header processing in time-division-multiplexed networks, we also demonstrate the cascaded operation of two low-bi NOLM's. Using a passively mode-locked fiber laser that produces 450-fs pulses at a wavelength of 1.55 microm, we achieve a 10.7:1 switching contrast ratio and a 2.7-pulse-widths-wide timing window after the cascaded gates. The results agree well with theoretical predictions and confirm the advantages of the long interaction length associated with orthogonally polarized pulses in low-bi (Deltan ~ 3.0 x 10(-6)) polarization-maintaining fiber.

12.
Appl Opt ; 32(31): 6399-406, 1993 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20856478

RESUMO

Optical-fiber strain gauges with asymmetric etched structures have been analyzed, fabricated, and tested. These sensors are very sensitive with a gauge factor as high as 170 and a flat frequency response to at least 2.7 kHz. The gauge factor depends on the asymmetry of the etched structures and the number of etched sections. To understand the physical principles involved, researchers have used structural analysis programs based on a finite-element method to analyze fibers with asymmetric etched structures under tensile stress. The results show that lateral bends are induced on the etched fibers when they are stretched axially. To relate the lateral bending to the optical attenuation, we have also employed a ray-tracing technique to investigate the dependence of the attenuation on the structural deformation. Based on the structural analysis and the ray-tracing study parameters affecting the sensitivity have been studied. These results agree with the results of experimental investigations.

14.
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