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1.
Malays Orthop J ; 18(1): 51-59, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38638659

RESUMO

Introduction: Deformities of the spine and thorax in adolescent idiopathic scoliosis affect appearance. They are a cause of inferiority, affecting psychological well-being and the social life of the patients. To contribute to curve evaluation, planning in curve correction, and improving the post-operative aesthetics, many studies on the correlation between appearance and radiography in the assessment of shoulder and neck balance have been reported recently. In general, these studies did not clarify which indices are required to evaluate shoulder and neck balance. This study aimed to learn about indices to assess shoulder and neck balance in adolescent idiopathic scoliosis in correlation between clinical appearance and radiography. Materials and methods: This observational study recruited 50 patients with adolescent idiopathic scoliosis who were 12 to 18 years of age with Cobb angle >10°. Based on Pearson correlation coefficient, radiographic parameters such as coracoid height difference (CHD), clavicle rib intersection distance (CRID), clavicle angle (CA), clavicle chest cage angle difference (CCAD), and T1 tilt angle were evaluated in correlation with clinical shoulder and neck balance by difference of inner shoulder height (SHi), difference of outer shoulder height (SHo), and neck tilt angle. Results: SHi was moderately correlated with T1 tilt angle (r [hereafter] = 0.45), CA (0.47), and CHD (0.57), high-moderately correlated with CRID (0.64), very-highly correlated with CCAD (0.84). SHo was moderately correlated with T1 tilt angle (0.43), highly correlated with CHD (0.60), CA (0.63), and CRID (0.72), and very-highly correlated with CCAD (0.89). T1 tilt angle was high-moderately correlated with neck tilt angle (0.76). The correlation coefficients between clinical and radiographic shoulder and neck balance according to sex, BMI, type of main curve, severity of main curve did not change significantly. Conclusion: There was a very high correlation between SHo (shoulder tilt) and CCAD (0.89); the correlation between SHo and CRID was high-moderate (0.72), but CRID is easier than CCAD to evaluate on radiographs. On the other hand, T1 tilt angle, which is the easiest radiographic parameter to evaluate, had a high-moderate correlation with neck tilt angle (0.76) but a moderate correlation with SHo (0.43).

2.
Cancer Res ; 61(4): 1338-46, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11245431

RESUMO

Aromatase (estrogen synthetase) is expressed in breast cancer tissue, and in situ expression of the enzyme stimulates breast cancer growth. Promoter I.3 is one of the major promoters that control the expression of aromatase in breast cancer tissue. Using the yeast one-hybrid approach to screen a human breast tissue hybrid cDNA expression library, we found that the zinc-finger transcriptional factor Snail (SnaH) interacted with a regulatory region near promoter I.3 of the human aromatase gene. DNA mobility shift assays and mutation analyses using recombinant SnaH protein expressed in Escherichia coli have revealed that this protein interacts with a segment, 5'-CTGATGAAGT-3', which is between 66 and 76 bp upstream from the transcriptional start site of promoter I.3. Using mammalian cell transfection experiments, SnaH was found to act as a repressor of promoter I.3 activity. Site-directed mutagenesis experiments have revealed that the NH2-terminal SNAG domain is important for the repressor activity of SnaH. To demonstrate the inhibitory activity against aromatase expression, a stable SnaH-expressing MDA-MB-231 breast cancer cell line was generated, and the aromatase RNA messages in the SnaH-transfected cell line were found to be 30% of those in the vector-transfected cell line. Reverse transcription-PCR analysis on RNAs isolated from 12 cell lines has confirmed that SnaH is expressed at a higher level in normal breast epithelial cell and stromal fibroblast cell lines than in breast cancer cell lines. In addition, SnaH mRNA was detected in only 16 of 55 breast cancer specimens. On the other hand, aromatase mRNA was detected in 54 of the 55 specimens. Our results indicate that SnaH acts as a repressor that down-regulates the expression of aromatase in normal breast tissue by suppressing the function of promoter I.3. A reduction of the expression of SnaH in breast cancer tissue further suggests a cancer-protective role for this protein in normal breast tissue.


Assuntos
Aromatase/genética , Mama/fisiologia , Proteínas de Ligação a DNA/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Mama/enzimologia , Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo/fisiologia , Regulação Enzimológica da Expressão Gênica , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Fatores de Transcrição da Família Snail , Fatores de Transcrição/biossíntese , Fatores de Transcrição/metabolismo , Dedos de Zinco/genética
3.
IEEE Trans Image Process ; 9(4): 529-35, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-18255426

RESUMO

In this paper, a fast encoding algorithm is developed for fractal image compression. At each search entry in the domain pool, the mean square error (MSE) calculations of the given range block and the eight dihedral symmetries of the domain block are obtained simultaneously in the frequency domain, in which the redundant computations are all eliminated in the new encoding algorithm. It is shown in software simulation that the encoding time is about six times faster than that of the baseline method with almost the same PSNR for the retrieved image. The fast algorithm is performed to deal with the eight dihedral symmetries at each search entry. Therefore, it can be applied to various enhanced algorithms which are equipped with quadtree, classification, and other mechanisms.

4.
IEEE Trans Image Process ; 9(11): 1988-95, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-18262936

RESUMO

A new cubic convolution spline interpolation (CCSI )for both one-dimensional (1-D) and two-dimensional (2-D) signals is developed in order to subsample signal and image compression data. The CCSI yields a very accurate algorithm for smoothing. It is also shown that this new and fast smoothing filter for CCSI can be used with the JPEG standard to design an improved JPEG encoder-decoder for a high compression ratio.

5.
Proc Inst Mech Eng H ; 215(3): 325-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11436276

RESUMO

Morse code is a simple, speedy and low cost means of communication composed of a series of dots, dashes and space intervals. Each tone element (either a dot, dash or space interval) is transmitted by sending a signal for a defined length of time. This poses a challenge as the automatic recognition of Morse code is dependent upon maintaining a stable typing rate. In this paper, a suitable adaptive automatic recognition method, combining the least-mean-square (LMS) algorithm with a neural network, was applied to this problem. The method presented in this paper is divided into five modules: space recognition, tone recognition, learning process, adaptive processing and character recognition. Statistical analyses demonstrated that the proposed method elicited a better recognition rate in comparison with other methods in the literature.


Assuntos
Comunicação , Pessoas com Deficiência/reabilitação , Redes Neurais de Computação , Algoritmos , Humanos
6.
IEEE Trans Comput ; C-34(5): 393-403, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-11539661

RESUMO

A pipeline structure of a transform decoder similar to a systolic array is developed to decode Reed-Solomon (RS) codes. An important ingredient of this design is a modified Euclidean algorithm for computing the error-locator polynomial. The computation of inverse field elements is completely avoided in this modification of Euclid's algorithm. The new coder is regular and simple, and naturally suitable for VLSI implementation. An example illustrating both the pipeline and systolic array aspects of this decoder structure is given for a RS code.


Assuntos
Algoritmos , Simulação por Computador , Sistemas Computacionais , Matemática
7.
IEEE Trans Comput ; C-34(8): 709-17, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11539660

RESUMO

Finite field arithmetic logic is central in the implementation of Reed-Solomon coders and in some cryptographic algorithms. There is a need for good multiplication and inversion algorithms that can be easily realized on VLSI chips. Massey and Omura recently developed a new multiplication algorithm for Galois fields based on a normal basis representation. In this paper, a pipeline structure is developed to realize the Massey-Omura multiplier in the finite field GF(2m). With the simple squaring property of the normal basis representation used together with this multiplier, a pipeline architecture is developed for computing inverse elements in GF(2m). The designs developed for the Massey-Omura multiplier and the computation of inverse elements are regular, simple, expandable, and therefore, naturally suitable for VLSI implementation.


Assuntos
Algoritmos , Simulação por Computador , Sistemas Computacionais , Matemática
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