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1.
Med J Malaysia ; 73(6): 365-370, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30647205

RESUMO

INTRODUCTION: Modulation-based noise reduction (MBNR) is one of the common noise reduction methods used in hearing aids. Gain reduction in high frequency bands may occur for some implementations of MBNR and fricatives might be susceptible to alteration, given the high frequency components in fricative noise. The main objective of this study is to quantify the acoustic effect of MBNR on /s, z/. METHODS: Speech-and-noise signals were presented to, and recorded from, six hearing aids mounted on a head and torso simulator. Test stimuli were nonsense words mixed with pink, cafeteria, or speech-modulated noise at 0 dB SNR. Fricatives /s, z/ were extracted from the recordings for analysis. RESULTS: Analysis of the noise confirmed that MBNR in all hearing aids was activated for the recordings. More than 1.0 dB of acoustic change occurred to /s, z/ when MBNR was turned on in four out of the six hearing aids in the pink and cafeteria noise conditions. The acoustics of /s, z/ by female talkers were affected more than male talkers. Significant relationships between amount of noise reduction and acoustic change of /s, z/ were found. Amount of noise reduction accounts for 42.8% and 16.8% of the variability in acoustic change for /s/ and /z/ respectively. CONCLUSION: Some clinically-available implementations of MBNR have measurable effects on the acoustics of fricatives. Possible implications for speech perception are discussed.


Assuntos
Auxiliares de Audição , Estimulação Acústica , Acústica , Humanos , Ruído , Fonética , Percepção da Fala
2.
Med J Malaysia ; 71(6): 348-350, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28087961

RESUMO

There are many options in the treatment of heavily pretreated metastatic breast cancer however none of the therapeutic agents have shown promising improvement of survival with good toxicity profile. Eribulin is a novel nontaxane microtubule dynamics inhibitor. Two recent clinical trial showed that Eribulin improves progression-free and overall survival in this subset of patients. We report our experience with using Eribulin in five patients with metastatic breast cancer either in second or third-line setting, in our centre.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Furanos/uso terapêutico , Cetonas/uso terapêutico , Feminino , Humanos , Malásia , Metástase Neoplásica , Resultado do Tratamento
3.
Med J Malaysia ; 70(2): 110-1, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26162391

RESUMO

We present a case of nasopharyngeal carcinoma complicated with hyperleucocytosis. After ruling our other causes we concluded that the hyperleucocytosis was due to paraneoplastic leukemoid reaction (PLR). The overall survival was 15 months which is rare among patients with PLR.

4.
Allergy ; 69(4): 545-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24697356

RESUMO

There are few published studies on prevalence of allergic rhinitis in preschool children. The aims of this study were to verify the prevalence, clinical characteristics, and treatment of allergic rhinitis (AR) symptoms in the first year of life adding supplementary questions to the EISL instrument. A cross-sectional study used Phase III EISL written questionnaire in addition to modified allergic rhinitis ISAAC questions. One thousand and three parents of infants answered the questionnaire: 484 (48.3%) had at least one sneezing, or a runny or blocked nose episodes without cold or flu in the first year of life. A quarter of infants had recurrent wheezing (≥3 episodes) and more frequent in the presence of AR symptoms. Physician diagnosis of AR and the use of intranasal steroids and both antihistamines and intranasal steroids were more common among those infants with AR symptoms. The prevalence of AR symptoms was high and starting early in life.


Assuntos
Rinite Alérgica Perene/epidemiologia , Idade de Início , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Prevalência , Rinite Alérgica , Rinite Alérgica Perene/diagnóstico
5.
ESMO Open ; 7(4): 100518, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35797737

RESUMO

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of prostate cancer was published in 2020. It was therefore decided, by both the ESMO and the Singapore Society of Oncology (SSO), to convene a special, virtual guidelines meeting in November 2021 to adapt the ESMO 2020 guidelines to take into account the differences associated with the treatment of prostate cancer in Asia. These guidelines represent the consensus opinions reached by experts in the treatment of patients with prostate cancer representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with prostate cancer across the different regions of Asia.


Assuntos
Oncologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Ásia , Consenso , Europa (Continente) , Seguimentos , Humanos , Masculino
6.
ESMO Open ; 6(6): 100304, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34864348

RESUMO

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of renal cell carcinoma was published in 2019 with an update planned for 2021. It was therefore decided by both the ESMO and the Singapore Society of Oncology (SSO) to convene a special, virtual guidelines meeting in May 2021 to adapt the ESMO 2019 guidelines to take into account the ethnic differences associated with the treatment of renal cell carcinomas in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with renal cell carcinoma representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Ásia , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/terapia , Seguimentos , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/terapia , Oncologia
7.
Cardiovasc Drugs Ther ; 24(2): 107-20, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20379769

RESUMO

PURPOSE: We assessed the effects of TAK-491 (a newly designed potent and selective ARB) alone and in combination with pioglitazone (PIO) on myocardial infarct size (IS). METHODS: Rats received TAK-491 (0.3, 1, 3, or 10 mgkg(-1)d(-1)), PIO (1.0 or 2.5 mgkg(-1)d(-1)), or PIO 2.5 mgkg(-1)d(-1) with TAK-491 (1 or 3 mgkg(-1)d(-1)) for 4 days. On day 5 rats underwent 30-minute coronary artery occlusion and 4-hour reperfusion. Area at risk (AR) was assessed by blue dye and IS by TTC. Left ventricular (LV) dimensions and function was assessed by echocardiography 35 days after infarction. RESULTS: TAK (1.0-10 mgkg(-1)d(-1)), PIO (1.0 to 2.5 mgkg(-1)d(-1)), PIO2.5+TAK1.0, and PIO2.5+TAK3.0 significantly reduced IS. IS was the smallest in the TAK 10.0, followed by PIO+TAK 3.0. The protective effects of TAK and PIO were additive, as IS was smaller in the PIO2.5+TAK1.0 than in PIO 2.5 alone (p = 0.008) or TAK1.0 alone (p = 0.002); and in PIO2.5+TAK3.0 than in PIO alone (p < 0.001) or TAK3.0 alone (p < 0.001). TAK, PIO and their combination tended to attenuate LV remodeling and improved LV function 35 days after infarction; however, the differences among individual groups were not statistically significant. Both TAK-491 and PIO increased calcium-dependent nitric oxide synthase activity, whereas only PIO increased COX2 expression and activity. Both PIO and TAK-491 increased Akt, ERK 1/2 and eNOS phosphorylation and inhibited BAX activation. CONCLUSIONS: TAK-491 and PIO independently limited myocardial IS in a dose-dependent fashion; and the effects were additive. The mechanism of protection and the role of TAK-491 in this clinical setting should be further investigated.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Tiazolidinedionas/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Quimioterapia Combinada , Frequência Cardíaca/fisiologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Masculino , Proteínas de Membrana/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Pioglitazona , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Tiazolidinedionas/farmacologia , Função Ventricular Esquerda/fisiologia , Proteína X Associada a bcl-2/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Malays J Pathol ; 31(1): 35-43, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19694312

RESUMO

Cyclosporine A (CsA), a calcineurin inhibitor produced by the fungi Trichoderma polysporum and Cylindrocarpon lucidum, is an immunosuppressant prescribed in organ transplants to prevent rejection. Its adverse effect on renal dysfunction has limited its use in a clinical setting. Apigenin (4',5',7'-Trihydroxyflavone), a herbal extract, with anti-inflammatory and anti-tumour properties, has been investigated for properties to reverse this adverse effect. This research was conducted to establish a standard protocol for immunohistochemical estimation of Transforming Growth Factor beta (TGF-beta) expression, as an indicator of Cyclosporine A induced damage, and to observe whether apoptotic index and TGF-beta expression can be used to assess effects of Apigenin on CsA induced renal dysfunction. Six groups of 5 male Sprague-Dawley albino rats each were dosed once daily for 21 days, as follows: (1) negative control--oral corn oil, (2) positive control--Cyclosporine A (25 mg/kg), (3) Group 3--Apigenin (20 mg/kg), (4) Group 4--Cyclosporine A (25 mg/kg) +Apigenin (10 mg/kg), (5) Group 5--Cyclosporine A (25 mg/kg) +Apigenin (15 mg/kg) and (6) Group 6--Cyclosporine A (25 mg/kg) +Apigenin (20 mg/kg). Cyclosporine A was administered intra-peritoneally while Apigenin was given orally. The rat kidneys were harvested and examined microscopically to assess the apoptotic index, and stained by immunohistochemistry for multifunctioning polypeptide TGF-beta expression. A high apoptotic index and TGF-beta intensity was observed in the Cyclosporine A group. Apigenin significantly reduced the both apoptotic index and TGF-beta intensity. The apoptotic index correlated with TGF-beta intensity, especially in glomeruli. This study indicates that Cyclosporine A can enhance the TGF-beta expression in rat kidney, signifying accelerated apoptosis. TGF-beta and apoptotic index may be used to assess Apigenin and its effect on Cyclosporine A induced renal damage.


Assuntos
Apigenina/farmacologia , Apoptose/efeitos dos fármacos , Ciclosporina/toxicidade , Imunossupressores/toxicidade , Nefropatias/prevenção & controle , Fator de Crescimento Transformador beta/metabolismo , Administração Oral , Animais , Contagem de Células , Antagonismo de Drogas , Imuno-Histoquímica , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
9.
Meat Sci ; 154: 86-95, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31022586

RESUMO

This study was commissioned to assess if there are regional differences in the acceptability of beef between consumers from Northern Ireland (NI), Republic of Ireland (ROI) and Great Britain (GB). Palatability traits were affected by socioeconomic and behavioural factors such as preferred cooking endpoint, animal welfare, value, health aspects of beef product, ease of preparation as well as consumption frequency for specific cuts. "Willingness to pay" (WTP) was influenced by income, preferred cooking endpoint, value of beef product, ease of preparation and consumption frequency for frying steak. Results showed that GB consumers scored higher for the same striploin steak compared to NI and ROI consumers. This may be due to differences in the motivation for beef choice and/or consumption habits. GB consumers were less concerned about the healthiness of beef product and beef origin. In addition, a higher consumption frequency for rump was reported in GB, which may explain the higher sensory scores observed among GB consumers for striploins.


Assuntos
Comportamento de Escolha , Comportamento do Consumidor , Carne Vermelha/economia , Carne Vermelha/normas , Animais , Bovinos , Culinária/métodos , Feminino , Humanos , Masculino , Irlanda do Norte , Fatores Socioeconômicos , Paladar , Reino Unido
10.
J Am Coll Cardiol ; 21(4): 901-9, 1993 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8450158

RESUMO

OBJECTIVES: The purpose of this study was to determine the safety and efficacy of radiofrequency ablation as definitive therapy for primary atrial tachycardias. BACKGROUND: Primary atrial tachycardias are often difficult to control with antiarrhythmic medications and frequently require nonpharmacologic interventions for definitive therapy. Despite isolated reports of successful treatment of primary atrial tachycardias with radiofrequency ablation, the safety and efficacy of this technique have not been established in a larger series with long-term follow-up. METHODS: The immediate procedural success rate, associated complications and follow-up data of radiofrequency ablation were evaluated in 15 consecutive patients (11 adults and 4 children) with primary atrial arrhythmias that were refractory to medical management. RESULTS: The clinical arrhythmia was ectopic atrial tachycardia in 11 patients and sinus node reentry in 4. The site of origin of the tachycardia was in the right atrium in 14 patients and in the left atrium in 1 patient (with two distinct foci) where the local atrial electrogram preceded the onset of the P wave by 10 to 30 ms. Radiofrequency energy successfully terminated the primary atrial tachycardia in each of the patients, and all were discharged from the electrophysiology laboratory in sinus rhythm without inducible atrial tachycardia. A mean of 10.8 +/- 9.9 radiofrequency applications were delivered using 30 W of power for 30 s. The local intracardiac activation time (relative to the P wave in the surface electrocardiogram) was a mean of -21 +/- 5 ms at the successful ablation site and -15 +/- 6 ms at unsuccessful sites (p < 0.001). No complications were observed, although one patient with incessant ectopic atrial tachycardia had sinus pauses after ablation. During a mean follow-up period of 277 +/- 133 days, the clinical arrhythmia recurred in three patients (20%, 95% confidence intervals 3% to 37%) including two patients with ectopic atrial tachycardia and one patient with sinus node reentry. One of these patients was successfully treated in a second ablation session. CONCLUSIONS: Thus, radiofrequency catheter ablation appears to be a safe and effective technique for the treatment of primary atrial arrhythmias that are refractory to antiarrhythmic medications.


Assuntos
Ablação por Cateter , Taquicardia por Reentrada no Nó Sinoatrial/cirurgia , Taquicardia/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Eletrocardiografia , Feminino , Seguimentos , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Taquicardia/fisiopatologia , Taquicardia por Reentrada no Nó Sinoatrial/fisiopatologia , Resultado do Tratamento
11.
Med Biol Eng Comput ; 43(5): 638-47, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16411637

RESUMO

An adaptive signal enhancer based on third-order statistics with a genetic-type, variable step-size prefilter is introduced to recover evoked potentials (EPs). EPs are usually embedded in the ongoing electroencephalogram with a very low signal-to-noise ratio (SNR). As a higher-order statistics technique has a natural tolerance to Gaussian noise, it is applicable for filtering EPs. An adaptive signal enhancer based on third-order statistics was used as the major filter in this study. However, the efficiency of the adaptive signal enhancer was reduced when the total power of uncorrelated noises was large. To improve the performance for EPs under poor SNR, a low-noise signal is required. Therefore a prefilter with a genetic-type, variable step-size algorithm was employed to enhance the SNR of the signal in this study. The fundamental idea of a genetic-type, variable step-size algorithm is that its step-sizes are regularly readjusted to optimum. Therefore this algorithm can be used as a prefilter with different noise levels. Experimental results showed that, for filtering EPs, the proposed scheme is superior to the adaptive signal enhancer with a normalised least mean square algorithm.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados , Processamento de Sinais Assistido por Computador , Algoritmos , Humanos
12.
Chest ; 102(4): 1110-2, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1395753

RESUMO

Malignant mesothelioma of the pleura is a disease that requires a biopsy procedure for a definitive diagnosis. In the past, closed pleural needle biopsy (CPNB) has given poor yields due to the small amount of tissue obtained, and the patient has subsequently been subjected to a diagnostic thoracotomy. In recent years, the availability of more accurate histopathologic tests have enabled the pathologist to make a diagnosis more easily on samples obtained at CPNB. In this retrospective study of 20 consecutive cases of malignant mesothelioma of the pleura diagnosed between 1980 and 1990, we found that a blind CPNB was diagnostic in five of seven procedures and CT-guided CPNB was diagnostic in five of six procedures. An open pleural biopsy (OPB) was diagnostic in ten of ten procedures performed. There were no complications associated with any of the CPNB procedures. We conclude that CPNB is a safe and effective manner of diagnosing malignant mesothelioma of the pleura, and should be attempted prior to OPB.


Assuntos
Biópsia por Agulha , Mesotelioma/diagnóstico , Pleura/patologia , Neoplasias Pleurais/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Surgery ; 97(5): 613-7, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-3992484

RESUMO

Presented is a patient with a tumor containing elements from two germ layers. It was associated within the patient's thyroid gland (located in a benign adenoma), but since the elements were widely separated from each other the tumor could not be classified as a teratoma or hamartoma. To our knowledge no similar tumor has been described. The interesting characteristics of this patient are described. The characteristics of this benign tumor are compared with those of cases in the literature of adult thyroid teratomas.


Assuntos
Teratoma/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Teratoma/cirurgia , Neoplasias da Glândula Tireoide/cirurgia
14.
Pancreas ; 5(3): 330-3, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-1693000

RESUMO

To confirm the accuracy of guided percutaneous aspiration (GPA) in distinguishing sterile from infected pancreatic necrosis, we have performed Brown-Brenn tissue Gram stains on pancreatic and peripancreatic necrotic tissue removed operatively in 15 patients. In eight patients judged to have sterile necrosis on the basis of negative cultures of pancreatic exudate obtained first preoperatively (by GPA) and then intraoperatively, necrotic tissue debrided at surgery was also free of bacteria. In seven patients judged to have infected necrosis on the basis of positive cultures of pancreatic exudate obtained first preoperatively (by GPA) and then intraoperatively, necrotic tissue debrided at surgery harbored a considerable number of bacteria. We conclude that GPA targeted to areas of necrosis accurately distinguishes infected necrosis from sterile necrosis, and in infected necrosis, the solid necrotic tissue as well as the fluid component contains bacteria. We therefore believe that infected necrosis is not likely to be eradicated by catheter drainage and should be treated by surgical debridement.


Assuntos
Pancreatite/microbiologia , Técnicas Bacteriológicas , Humanos , Período Intraoperatório , Necrose/microbiologia , Pancreatite/patologia , Cuidados Pré-Operatórios , Coloração e Rotulagem
15.
Neurosurgery ; 12(4): 463-8, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6856074

RESUMO

We report two patients who underwent orbital exploration yielding the diagnosis of sclerosing orbital pseudotumor. The presenting symptoms were exophthalmos, visual loss, abnormal ocular mobility, and ocular pain. Computed tomographic (CT) scans showed masses in the orbital apex. Steroids were ineffective. Orbital pseudotumor is a heterogeneous diagnostic category of lymphoid infiltrations of the orbit with a wide spectrum of pathological conditions and intraorbital locations. The clinical presentation typically includes the sudden onset of pain, diplopia, lid edema, and exophthalmos. Visual loss is uncommon. Most cases resolve spontaneously or respond to steroid treatment. Although fibrosis may be a prominent histological finding, the literature contains little information concerning its significance. We discuss the evidence for considering the sclerosing pseudotumors to be a significant variant with unique clinical behavior. Although features suggestive of pseudotumor were present in our case, the presence of visual loss and an apical mass shown on the CT scan led to the presumptive diagnosis of tumor and exploratory operation. Neurosurgeons should be aware of this entity as a cause of visual loss and orbital mass. Proper suspicion may in some cases permit transorbital biopsy and avoid craniotomy, inasmuch as operation is of no therapeutic benefit in this disease.


Assuntos
Fibroma/cirurgia , Neoplasias Orbitárias/cirurgia , Adulto , Diagnóstico Diferencial , Feminino , Fibroma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Órbita/patologia , Neoplasias Orbitárias/patologia , Esclerose , Tomografia Computadorizada por Raios X
16.
J Pharm Biomed Anal ; 31(6): 1237-43, 2003 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-12667940

RESUMO

A sensitive enantioselective liquid chromatography-mass spectrometry (LC-MS) assay using a manual solid-phase extraction (SPE) procedure, a non-deuterated internal standard and an ion trap LC-MS was developed to measure (R)- and (S)-albuterol in plasma. Sample extraction from plasma was achieved by a manual SPE extraction procedure with methoxyphenamine added as the internal standard. Chiral separation was achieved using a teicoplanin-based stationary phase and a mobile phase consisting of methanol, acetic acid and 28% (w/v) ammonia (1000:5:1, v/v/v). Samples were analyzed by selected reaction monitoring of product ions from the protonated molecular ions. The detection limit of the assay was 0.1 ng/ml with a conservative lower limit of quantification of 0.25 ng/ml for each enantiomer. Recovery of albuterol enantiomers from plasma spiked at 10 ng/ml of racemate was determined to be 89+/-5.8% (mean+/-S.D.). Reproducibility at 10 ng/ml of racemate assessed by the coefficient of variation was found to be 6.5% (n=5). Instrument precision (measured as coefficient of variation) was 1.4% (n=5). The correlation coefficient r(2) determined from the calibration curve over the range 0.5-50.0 ng/ml racemate in plasma was 0.998. This assay allows adequate sensitivity, recovery and reproducibility for the application to studies of inhaled albuterol.


Assuntos
Albuterol/sangue , Albuterol/normas , Albuterol/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Estereoisomerismo
17.
Med Biol Eng Comput ; 39(6): 627-32, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11804167

RESUMO

The peripheral arterial vessel often appears as an elliptic shape under the constraints of the surrounding tissues. In this study, the gradient-based Hough transform was used to detect the central location of the ellipse and the lumen area of the arterial vessel non-invasively using power Doppler imaging. Sequential ultrasound images were used to construct arterial distension waveforms in both the major- and minor-axis directions for a few cardiac cycles. The common carotid arteries (CCAs) for nine healthy male volunteers (mean age 24 years), in the sitting position, were investigated in vivo. The CCAs (n = 9) had a mean diameter of 5.83mm, and the pulsatile diameter distension was 13.7+/-1.9%. The brachial artery and dorsalis pedis artery for five healthy male volunteers (mean age 26 years), in the supine position, had mean diameters of 4.03mm and 2.83mm and distensions of 16.7+/-4.6% and 15.5+/-5.4%, respectively. The movement of the arterial centre location during the cardiac cycle reflected the asymmetry of the reaction forces produced by the surrounding soft tissues. The present method can obtain the response of vessel distension to pulse pressure, as well as the constrained conditions of the arteries.


Assuntos
Artérias/diagnóstico por imagem , Fluxo Pulsátil , Ultrassonografia Doppler/métodos , Adulto , Artérias/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino
18.
Med Eng Phys ; 17(1): 64-70, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7704346

RESUMO

A scheme for localizing the epileptic focus is proposed. The scheme is on the basis of a model with an electric dipole inside a four-layer inhomogeneous spherical model of head and utilizes a nonlinear programming algorithm applying the gradient projection method. Various initial estimates are used to prove the stability of the implemented dipole model. Fourteen single spike data and the averaged spike data are used to localize the epileptic focus. The results of the usage of the averaged spike data show that the dipole position is compatible with visual inspection of experienced clinical physicians. The results of the usage of the single spike show that 11 of the 14 single spikes have dipole locations near the result of the averaged spike but the estimated dipole moments differ markedly from one another. The localization results of the other three single spikes show that the dipole position is strongly affected by the background EEG. This kind of interference generally causes the eccentricity of the dipole to deviate from its anatomically meaningful value. According to our results, the electric dipole model is concluded to be valuable for the clinical application of localizing epileptic foci.


Assuntos
Eletroencefalografia , Epilepsia/diagnóstico , Processamento de Sinais Assistido por Computador , Algoritmos , Simulação por Computador , Condutividade Elétrica , Epilepsia/fisiopatologia , Potenciais Evocados/fisiologia , Humanos , Modelos Anatômicos , Modelos Neurológicos , Dinâmica não Linear
19.
Med Eng Phys ; 17(1): 71-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7704347

RESUMO

In this paper, a well designed database, considering statistical characteristics and including all types of Electroencephalogram (EEG) is built. 900 EEG segments, each with a short interval (1.024 sec) in this database are clustered into eight classes. Three tests of white noise for evaluating the efficiency of autoregressive (AR) and autoregressive-moving average (ARMA) models are proposed. The Akaike information criterion (AIC) is used for determining orders of AR and ARMA models. The AR model requires a higher model order (8.67 on the average) than the ARMA model (6.17 on the average). However, it is found that about 96% of the 900 segments can be efficiently represented by the AR model, and only about 78% of them can be efficiently represented by ARMA model. We therefore conclude that the AR model is preferred for estimating EEG signals.


Assuntos
Eletroencefalografia , Modelos Biológicos , Processamento de Sinais Assistido por Computador , Algoritmos , Bases de Dados Factuais , Estudos de Avaliação como Assunto , Humanos , Análise de Regressão
20.
Med J Malaysia ; 59(2): 226-32, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15559174

RESUMO

Breast cancer is one of the commonest cancers among women in Malaysia. The relation between lifestyle practices and the risk of breast cancer in Chinese women aged 21-55 years were assessed using data collected from June to October 2001, via a face-to face interview in a case control study in the Breast Clinics of Kuala Lumpur Hospital and University Malaya Medical Centre. A total of 89 cases with breast cancer were compared with 85 controls without the disease. Our study showed that breastfeeding had an odds ratio of 4.43 after adjustment for confounders. The results add to the evidence of a protective association between breast feeding practices and breast cancer particularly among Chinese women receiving treatment at two government hospitals in the Klang Valley.


Assuntos
Aleitamento Materno , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Estilo de Vida , Adulto , Neoplasias da Mama/etnologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , China/etnologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Malásia/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , População Rural
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