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1.
AJNR Am J Neuroradiol ; 37(7): 1318-23, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26892984

RESUMO

BACKGROUND AND PURPOSE: Inflow jet characteristics may be related to aneurysmal bleb formation and rupture. We investigated the visualization threshold on the basis of the flow velocity in the parent artery to classify the inflow jet patterns observed on 4D flow MR imaging. MATERIALS AND METHODS: Fifty-seven unruptured aneurysms (24 bifurcation and 33 sidewall aneurysms) were subjected to 4D flow MR imaging to visualize inflow streamline bundles whose velocity exceeded visualization thresholds corresponding to 60%, 75%, and 90% of the maximum flow velocity in the parent artery. The shape of the streamline bundle was determined visually, and the inflow jet patterns were classified as concentrated, diffuse, neck-limited, and unvisualized. RESULTS: At the 75% threshold, bifurcation aneurysms exhibited a concentrated inflow jet pattern at the highest rate. At this threshold, the inflow jets were concentrated in 13 aneurysms (group C, 22.8%), diffuse in 18 (group D, 31.6%), neck-limited in 11 (group N, 19.3%), and unvisualized in 15 (group U, 26.3%). In 16 (28.1%) of the 57 aneurysms, the inflow jet pattern was different at various thresholds. Most inflow parameters, including the maximum inflow velocity and rate, the inflow velocity ratio, and the inflow rate ratio, were significantly higher in groups C and D than in groups N and U. CONCLUSIONS: The inflow jet pattern may depend on the threshold applied to visualize the inflow streamlines on 4D flow MR imaging. For the classification of the inflow jet patterns on 4D flow MR imaging, the 75% threshold may be optimal among the 3 thresholds corresponding to 60%, 75%, and 90% of the maximum flow velocity in the parent artery.


Assuntos
Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Hemodinâmica , Humanos
2.
AJNR Am J Neuroradiol ; 36(2): 342-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25234030

RESUMO

BACKGROUND AND PURPOSE: Future aneurysmal behaviors or treatment outcomes of cerebral aneurysms may be related to the hemodynamics around the inflow zone. Here we investigated the influence of parent artery curvature on the inflow zone location of unruptured sidewall internal carotid artery aneurysms. MATERIALS AND METHODS: In 32 aneurysms, the inflow zone location was decided by 4D flow MR imaging, and the radius of the parent artery curvature was measured in 2D on an en face image of the section plane corresponding to the aneurysm orifice. RESULTS: The inflow zone was on the distal neck in 10 (group 1, 31.3%), on the lateral side in 19 (group 2, 59.4%), and on the proximal neck in 3 (group 3, 9.4%) aneurysms. The radius in group 1 was significantly larger than that in group 2 (8.3 mm [4.5 mm] versus 4.5 mm [1.9 mm]; median [interquartile range]; P < .0001). All 7 aneurysms with a radius of >8.0 mm were in group 1. All 18 aneurysms with a radius of <6.0 mm were in group 2 or 3. In two group 3 aneurysms, the inflow zone was located in a part of the neck extending beyond the central axis of the parent artery. CONCLUSIONS: The inflow zone locations of sidewall aneurysms can be influenced by the parent artery curvature evaluated in 2D on an en face image of the section plane corresponding to the aneurysm orifice.


Assuntos
Doenças das Artérias Carótidas/patologia , Artéria Carótida Interna/patologia , Hemodinâmica/fisiologia , Aneurisma Intracraniano/patologia , Doenças das Artérias Carótidas/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Humanos , Aneurisma Intracraniano/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos
3.
J Sports Sci ; 24(6): 589-96, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16608771

RESUMO

This study examined a method of predicting body density based on hydrostatic weighing without head submersion (HWwithoutHS). Donnelly and Sintek (1984) developed a method to predict body density based on hydrostatic weight without head submersion. This method predicts the difference (D) between HWwithoutHS and hydrostatic weight with head submersion (HWwithHS) from anthropometric variables (head length and head width), and then calculates body density using D as a correction factor. We developed several prediction equations to estimate D based on head anthropometry and differences between the sexes, and compared their prediction accuracy with Donnelly and Sintek's equation. Thirty-two males and 32 females aged 17-26 years participated in the study. Multiple linear regression analysis was performed to obtain the prediction equations, and the systematic errors of their predictions were assessed by Bland-Altman plots. The best prediction equations obtained were: Males: D(g) = -164.12X1 - 125.81X2 - 111.03X3 + 100.66X4 + 6488.63, where X1 = head length (cm), X2 = head circumference (cm), X3 = head breadth (cm), X4 = head thickness (cm) (R = 0.858, R2 = 0.737, adjusted R2 = 0.687, standard error of the estimate = 224.1); Females: D(g) = -156.03X1 - 14.03X2 - 38.45X3 - 8.87X4 + 7852.45, where X1 = head circumference (cm), X2 = body mass (g), X3 = head length (cm), X4 = height (cm) (R = 0.913, R2 = 0.833, adjusted R2 = 0.808, standard error of the estimate = 137.7). The effective predictors in these prediction equations differed from those of Donnelly and Sintek's equation, and head circumference and head length were included in both equations. The prediction accuracy was improved by statistically selecting effective predictors. Since we did not assess cross-validity, the equations cannot be used to generalize to other populations, and further investigation is required.


Assuntos
Adiposidade/fisiologia , Antropometria/métodos , Composição Corporal/fisiologia , Cabeça/fisiologia , Imersão , Dobras Cutâneas , Adolescente , Adulto , Fatores Etários , Povo Asiático , Impedância Elétrica , Feminino , Humanos , Japão , Masculino
4.
J Sports Med Phys Fitness ; 46(1): 62-70, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16596101

RESUMO

AIM: There are few studies on muscle power during local muscle contractions with a small range of motion such as in gripping. The purposes of this study were to clarify the properties of the developmental phase based on time series of muscle power output, the reliability of the parameters, their relationships and the load intensity derived peak power by gender differences, and to examine the possibility of evaluating muscle power using gripping. METHODS: Fifteen young males and 15 females participated in this study. Based on a crossover experimental design, each subject carried out 2 explosive grips at 20%, 30%, 40% and 50% loads of maximal using a voluntary grip contraction (MVC). The grip contraction velocities, sampled at 100 Hz, were measured accurately using a power instrument with an accelerometer. Muscle power curves were drawn from the product of the velocity and the set-up load. RESULTS: The cross-correlation coefficients between the trials for the average curve of the time-series moving distance, the velocity, and the power in any load were very high (over 0.95) in both genders. The reliability of each parameter was mostly good in both genders (intraclass correlation coefficient, ICC>0.75). The peak power curve differed between genders, and the curve around the peak value in females was irregular. CONCLUSIONS: A gender difference was found in the maximal power and the properties of the power curve. The maximal muscle power appeared at 30-50% MVC in males, and at 20-40% MVC in females. The peak power during the whole contraction, and the time to peak may reflect the conditions throughout the whole of the contraction. The new device used in this study to evaluate local regional muscle power (grip) is a very reliable and useful tool.


Assuntos
Força da Mão/fisiologia , Contração Muscular/fisiologia , Adulto , Feminino , Humanos , Masculino , Movimento (Física) , Fatores Sexuais
5.
J Sports Med Phys Fitness ; 45(2): 229-37, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16355086

RESUMO

AIM: This study aimed to examine the sway characteristics of center of foot pressure (CFP) movement during a static upright posture under the influence of alcohol by using quantitative and fractal analysis. METHODS: Eleven healthy young people participated. They drank in a range of 0.54-1.83 ml/kg of alcohol, standardized by body mass, within 10 min. Blood pressure, heart rate, 2 types of nervous function tests and the CFP movement were measured before and after the alcohol intake. Thirty-six parameters of the CFP movement were used for quantitative analysis. Diffusion coefficient, scaling exponent and critical point coordinates were used in fractal analysis. RESULTS: Quantitative analysis confirmed that the CFP parameters such as distance, velocity and area were significantly changed, although the parameters evaluating cyclical characteristics and center average were not. Fractal analysis confirmed that critical point coordinates existed at time-lag=1.0 before and after the alcohol intake, and the short-term region (ST) and long-term region (LT) could be separated. A diffusion coefficient in the ST was larger than that in the LT, and the scaling exponent was over 0.5 in the ST and under 0.5 in the LT. CONCLUSIONS: Influences of alcohol intake were found in amount of body-sway, but not in the displacement or periodicity of the CFP parameters. Fractal analysis confirmed that CFP movement was dependent on time-series, and its characteristics changed before and after the time-series critical point and was unsteady.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Etanol/farmacologia , Fractais , Equilíbrio Postural/efeitos dos fármacos , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/sangue , Pressão Sanguínea , Etanol/sangue , Feminino , Pé/fisiologia , Frequência Cardíaca , Humanos , Masculino , Postura , Pressão , Tempo de Reação/efeitos dos fármacos
6.
J Sports Med Phys Fitness ; 45(1): 68-76, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16208293

RESUMO

AIM: This study aimed to compare the accuracy of percent total body fat (%TBF) and percent segmental fat (%SF) measurements of new automatic single-frequency bioelectrical impedance analysis with 8 electrodes (SF-BIA8), referenced to the dual-energy X-ray absorptiometry (DXA), between different fatness level female groups. METHODS: Subjects were 34 overweight females (OWG) and 24 normal females (NG). This study used the BIA analyzer of Tanita BC-118 which is a commercially available single frequency bioelectrical impedance analysis system with 8 tactile electrodes. RESULTS: Test-retest reliability in each method was high (intra-class correlations > or =0.96). The SF-BIA8 tends to overestimate %TBF and %SF in the lower extremities and trunk compared with DXA, and consistency with DXA was especially low in %SFs in the lower extremities (left leg: r=0.475, SEE=4.673, right leg: r=0.494, SEE=4.772). Systematic errors regarding to the difference in fatness were found in %TBF and %SFs in lower extremities in OWG, and were found in %SF in upper extremities in NG. Furthermore, systematic errors regarding to the difference in body fat distribution were found in %SFs in lower extremities in OWG, and found in %SFs in upper extremities and trunk in NG. CONCLUSIONS: SF-BIA can provide highly reproducible measurements of %TBF and %SF, but systematic errors based on the differences in fatness and body fat distribution were found. An improved prediction equation considering a variety in fat and body fat distribution will be needed in further investigations.


Assuntos
Adiposidade/fisiologia , Impedância Elétrica , Absorciometria de Fóton , Adulto , Eletrodos , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
7.
Exp Gerontol ; 32(1-2): 161-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9088913

RESUMO

In a series of inbred Senescence-Accelerated mice (SAM) strains, accelerated-senescence prone SAMP substrains show early onset and rapid advancement of senescence. SAMP8 and SAMP10, in particular, exhibit a significant age-related deterioration in memory and learning for passive and active avoidance tasks with, respectively, a low and high incidence of systemic senile amyloidosis. In the brains of both SAMP8 and SAMP10 strains, we have found numerous morphological alterations. Here we review the changes seen in both neuronal or glial components in SAMP8/P10 brains. They may serve as markers of the neuronal degeneration leading to the deficits in learning and memory.


Assuntos
Envelhecimento/patologia , Deficiências da Aprendizagem/patologia , Transtornos da Memória/patologia , Envelhecimento/genética , Envelhecimento/psicologia , Animais , Deficiências da Aprendizagem/genética , Transtornos da Memória/genética , Camundongos , Camundongos Endogâmicos , Distrofias Neuroaxonais/patologia , Neurônios/patologia , Fenótipo , Fatores de Tempo
9.
Cancer ; 72(12): 3723-6, 1993 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8252489

RESUMO

BACKGROUND: Epipodophyllotoxins, etoposide and teniposide, have been shown to be implicated in the development, of acute myelogenous leukemia in patients treated for solid tumors or acute lymphoblastic leukemia. Etoposide has been shown to be an effective agent against Langerhans cell histiocytosis (LCH) and has gained wider use recently for first-line and salvage chemotherapy in cases of systemic LCH. METHODS: The authors report two patients with secondary acute promyelocytic leukemia (APL) with a t(15;17) abnormality after chemotherapy that included etoposide for the treatment of LCH. RESULTS: Patient 1, a 6-year-old girl, had APL develop 11 months after cessation of therapy that included vinblastine, prednisolone, and etoposide (9600 mg/m2 in total dose) for LCH. Patient 2, a 3-year-old girl, had APL develop 9 months after cessation of therapy that included vincristine, methotrexate, prednisolone, cyclophosphamide (10,800 mg/m2), and etoposide (4800 mg/m2) for LCH. CONCLUSIONS: The authors have experience with four patients treated with etoposide for LCH and suggest that there is a predisposition to secondary APL with t(15;17) for patients with LCH treated with etoposide. The authors warn against the imprudent use of etoposide as a first-line therapy for LCH.


Assuntos
Cromossomos Humanos Par 15 , Cromossomos Humanos Par 17 , Etoposídeo/efeitos adversos , Histiocitose de Células de Langerhans/tratamento farmacológico , Leucemia Promielocítica Aguda/induzido quimicamente , Translocação Genética , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia Promielocítica Aguda/genética
10.
Rinsho Shinkeigaku ; 32(1): 52-6, 1992 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-1628436

RESUMO

A Japanese woman, aged 42, was admitted because of paroxysmal attacks consisting of paresthesia of the left face, tremor in the right hand, epigastric pain and urinary incontinence. A year prior to the admission, she noticed some difficulty in writing, dysarthria and unsteadiness of walking. These symptoms had been persistent since then. At the end of March, 1991, these symptoms rapidly worsened, and she fell down frequently. She also experienced pain behind both eyes, numbness in her left fingers and toe, urinary frequency and the above-mentioned attacks. Neurological examination disclosed bilateral internuclear ophthalmoplegia and upbeating nystagmus on upward gaze, titubation in the head, scanning speech, dysmetria in all limbs, exaggerated reflexes in jaw and both legs, bilateral extensor plantar reflexes and ankle clonus. SEP showed delayed cortical response with stimulation of the median nerves bilaterally and of the right posterior tibial nerve. P40 was absent with the left posterior tibial nerve stimulation. VEP was normal. T2-weighted image of MRI showed multiple high intensity areas located around the third ventricle, crus cerebri and the right upper part of the pons. The diagnosis of multiple sclerosis was made. Each paroxysmal attack started with numbness in the left face and burning sensation in the neck. Almost simultaneously tremor in the right hand began. The surface EMG showed the rhythmic contractions in the dorsal hand muscles and wrist extensors at a frequency of 6-7 Hz, and sometimes it revealed synchronized contractions of finger flexors and the dorsal hand muscles. A few seconds later she felt painful sensation in the epigastric region, and the tremor gradually increased in its intensity.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Esclerose Múltipla/complicações , Dor Abdominal/etiologia , Adulto , Nervo Facial , Feminino , Lateralidade Funcional , Mãos , Humanos , Parestesia/etiologia , Tremor/etiologia , Incontinência Urinária/etiologia
12.
Gan To Kagaku Ryoho ; 15(2): 277-84, 1988 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-3422551

RESUMO

The effect of prostaglandin E1 (PGE1) on liver dysfunction due to high-dose methotrexate (HD-MTX) was investigated in children with malignant diseases. Eight children received 45 doses of HD-MTX. Group 1 (33 cases) received no PGE1. Group 2 (4 cases) received PGE1 intravenously 8 times every 12 hours for 3 consecutive days. Group 3 (8 cases) received infusion of PGE1 continuously for 4 days (1 day before and 3 consecutive days after MTX infusion). No significant difference was observed among the serum levels of transaminase in these 3 groups as well as the corresponding levels in the same patients who were treated with or without PGE1. There are reports suggesting that in spite of the lack of any difference in serum transaminase levels in rats with drug-induced hepatic injury given PGE1 infusion, data on DNA synthesis and survival ratio indicate the existence of 'hepatocytoprotection'. Further investigation will be necessary in order to decide whether PGE1 infusion is indeed effective.


Assuntos
Alprostadil/uso terapêutico , Leucemia Linfoide/tratamento farmacológico , Hepatopatias/prevenção & controle , Linfoma não Hodgkin/tratamento farmacológico , Metotrexato/efeitos adversos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/enzimologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia Linfoide/enzimologia , Linfoma não Hodgkin/enzimologia , Masculino , Metotrexato/administração & dosagem , Osteossarcoma/tratamento farmacológico , Osteossarcoma/enzimologia
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