RESUMO
Objective To compare the differences between the schizophrenics with negative and positive symptoms on prefrontal lobe and thalamus by proton magnetic resonance spectroscopy ( 1 H-MRS). Methods 58 negative subtype and 51 positive subtype schizophrenics were examined at prefrontal lobe and thalamus by multivoxel 1H-MRS before antipsychotic treatment The N-acetylaspartate (NAA), choline-containing compounds ( Cho), and creatine compounds (Cr) were measured and the ratios of NAA/Cr, Cho/Cr were determined. Results On right thalamus,the NAA/Cr ratio in negative subtype patients ( 1.40 ± 0.29 ) demonstrated lower than that in positive subtype ( 1.62 ± 0.33 ), the same phenomenon were appeared on male, female, non-first-episode, with-medicine and without-medicine patients (P < 0.05 or 0.01 ). The Cho/Cr ratio on right thalamus in negative subtype of female,non-first-episode,without-medicine schizophrenics were lower than those in positive subtype (P < 0.05 ).On left prefrontal lobe,left thalamus and right thalamus, the NAA/Cr ratios both in negative subtype and positive subtype schizophrenics were significantly negatively related with age of onset(P<0. 05 or 0.01 ). In negative subtype schizophrenics,the Cho/Cr ratio on right thalamus was positively related with age of onset ( r = 0. 25, P <0.05 ). In negative subtype schizophrenics of non-first-episode, without-medicine, the correlation was negative between the NAA/Cr ratio and the course of disease( r= -0.48, -0.46, P<0.05 ) ,and was positive between Cho/Cr ratio and the course of disease on right thalamus( r= 0.58,0.56, P< 0.01 ). Conlusion Compared with positive subtype schizophrenics,negative subtype schizophrenics have greater impairments on 1 H-MRS on right thalamus. The course of disease has greater effects on 1 H-MRS in negative subtype schizophrenics.
RESUMO
Biometric recognition methods for human identification have received researchers' attention. Seeing that the prominent characteristics of skull biometrics are not affected by facial expression and illumination, we present a new approach compounded of several features. Firstly, comparing the crania included angle; secondly, sampling the edge as the skull feature and analyzing the skull feature in multi-resolution; lastly, calculating the crania cavity area and regularizing the recognition rules. This method supports human identification in cases not only ante mortem but also postmortem.
Assuntos
Humanos , Algoritmos , Cefalometria , Métodos , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Métodos , Radiografia , Crânio , Diagnóstico por ImagemRESUMO
Skull recognition is a new method of biometrics recognition. A skull recognition algorithm is presented in this paper by Quadratic rational Bezier curve fitting which accurately describes the feature of skull edge; the experiment results based on skull x-ray image show the correctness of this method.