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91.
During mental rotation tasks using hand pictures, right-handers make left–right judgements by mentally rotating their own hand to an orientation of the presented hand image. Although strategy difference for the tasks between left- and right-handers has been suggested, the strategy of left-handers has been incompletely understood. In the present study we compared differences in reaction times between 15 left-handed and 16 right-handed normal individuals during a mental rotation task using simple hand pictures. Participants were required to identify pictures of a hand presented in four orientations (upright, counterclockwise rotated, clockwise rotated, and inverted) as either a right or a left hand. Right-handers recognised a right hand faster than a left hand, whereas no significant difference was seen for left-handers. Both left- and right-handers recognised a right hand faster than a left hand in counterclockwise-rotated images, and recognised a left hand faster than a right hand in clockwise-rotated images. The findings suggest that the differences in the reaction times between left- and right-handers depend on a laterality balance of hand motor skills. During mental rotation task using simple hand pictures, left-handers may mentally simulate their own hand to match the stimulus image as similar to right-handers. 相似文献
92.
Carlos Alberto de Carvalho Fraga Lucas Rodrigues Alves Luciano Marques-Silva Adriana Alkmim de Sousa Antonio Sérgio Barcala Jorge Sabrina Ferreira de Jesus Daniel Nogueira Vilela Ugo Borges Pinheiro Kimberly Marie Jones Alfredo Maurício Batista de Paula André Luiz Sena Guimarães 《Clinical oral investigations》2013,17(9):2011-2015
Objective
The aim of this study is to assess whether C1772T and G1790A hypoxia-inducible factor-1 (HIF-1)α polymorphisms are associated with risk of oral lichen planus (OLP).Material and methods
Restriction fragment length polymorphism analysis was used to investigate HIF-1α C1779T and G1790A polymorphisms in 32 OLP and 88 individuals without OLP.Results
The frequency of the CC, TT, GA, and AA genotypes was higher in patients with OLP. Notably, individuals carrying the C and A, and T and A haplotypes showed a significant association OLP risk.Conclusions
Our study demonstrated that the C1772T and G1790A polymorphisms of HIF-1α gene increased the risk of OLP. C1772T and G1790A polymorphisms of HIF-1α gene had differing patterns of allelic imbalance in the normal samples and subsequent chronic lesions. Further studies are necessary to elucidate the HIF-1α pathway in OLP, which would facilitate the development of novel therapeutic strategies for the prevention and treatment of OLP.Clinical relevance
These results, in conjunction with previous studies, suggest that HIF-1α may play important roles in the chronicity of oral mucosa lesions of OLP patients. Taken together, we suggest that HIF-1α polymorphisms enhance its target genes, thereby altering the microenvironment and supporting sequential release of inflammatory mediators or cellular events in OLP. It appears unlikely that inhibition of a single proinflammatory mediator will prove useful in clinical practice, but several ways to reprogram mediators engaged in a wide array of roles simultaneously are encouraging. 相似文献93.
Camila Santos PEREIRA Marcos Vinícius Macedo de OLIVEIRA Lucas Oliveira BARROS Gabriela Alencar BANDEIRA Sérgio Henrique Sousa SANTOS John R. BASILE André Luiz Sena GUIMAR?ES Alfredo Maurício Batista DE PAULA 《Journal of applied oral science : revista FOB》2013,21(5):416-421
Objective
This study aimed to investigate the expression of the MSH2 DNA repair protein in head and neck squamous cell carcinoma (HNSCC) in order to analyze its association with clinicopathologic factors and overall survival of patients.Material and Methods
Clinical data and primary lesions of HNSSC were collected from 55 patients who underwent surgical resection with postoperative radiotherapy in Montes Claros, state of Minas Gerais, Brazil, between 2000 and 2008. Immunohistochemical reactions were performed to analyze MSH2 protein expression.Results
Bivariate analysis showed no significant correlation or association between MSH2 expression and clinicopathologic parameters by Mann-Whitney and Kruskal-Wallis tests. Patients with locoregional metastatic disease (OR=4.949, p<0.001) and lower MSH2 immunohistochemical expressions (OR=2.943, p=0.032) presented poorer survival for HNSCC by Cox regression models.Conclusions
Our data demonstrated that lower MSH2 expression might contribute to a higher clinic aggressiveness of HNSCC by promoting an unfavorable outcome. 相似文献94.
Ryuta Shigefuku Hideaki Takahashi Minoru Kobayashi Hiroki Ikeda Kotaro Matsunaga Chiaki Okuse Nobuyuki Matsumoto Shiro Maeyama Shigeru Sase Michihiro Suzuki Fumio Itoh 《Journal of gastroenterology》2012,47(11):1238-1247
Introduction
Effective noninvasive tests that can distinguish early-stage nonalcoholic steatohepatitis (NASH) from simple steatosis (SS) have long been sought. Our aim was to determine the possibility of noninvasively distinguishing early-stage NASH from SS.Materials and methods
We used Fick’s principle and the Kety–Schmidt equation to determine the hepatic tissue blood flow (TBF) in 65 NASH patients who underwent xenon computed tomography (Xe-CT). We calculated the lambda value (LV), i.e., Xe gas solubility coefficient, in liver and blood. We assessed the histological severity of fatty changes and fibrosis on the basis of Brunt’s classification. Liver biopsy revealed SS in 9 patients and NASH in 56 patients. NASH stages 1 and 2 were classified as early-stage NASH (Ea-NASH; 38 patients) and stages 3 and 4 as advanced-stage NASH (Ad-NASH; 18 patients). We evaluated the differences in LV and TBF among the 3 groups.Results
LV was significantly lower in the Ad-NASH group than in the SS and Ea-NASH groups. Portal venous TBF (PVTBF) was significantly lower in the Ea-NASH group than in the SS group, and PVTBF was lower in the Ad-NASH group than in the Ea-NASH group. Total hepatic TBF (THTBF) was significantly different between the SS and Ea-NASH groups and between the SS and Ad-NASH groups.Conclusions
In conclusion, measurements of TBF and LV are useful for evaluating the pathophysiological progression of NASH. In addition, these measurements can facilitate the differential diagnosis of SS and Ea-NASH, which may not be distinguishable by other means. 相似文献95.
96.
97.
98.
Chiaki Okuse Hiroshi Yotsuyanagi Norie Yamada Hiroki Ikeda Minoru Kobayashi Yasunobu Fukuda Hideaki Takahashi Kotaro Matsunaga Nobuyuki Matsumoto Masaru Okamoto Toshiya Ishii Akira Sato Kazuhiko Koike Michihiro Suzuki Fumio Itoh 《Hepatology research》2012,42(12):1236-1240
Aim: Recently, patients positive for the low-titer hepatitis B surface antigen (HBsAg) have been found occasionally owing to the increase in the accuracy of detection methods. The aim of this study is to clarify the clinical status of acute hepatitis B virus (HBV) infection in patients positive for low-titer HBsAg. Method: Eight patients, who were positive for HBsAg at low titers and diagnosed as having acute HBV infection, were enrolled in this study. Assays of HBsAg, hepatitis B core antibody (anti-HBc), hepatitis B e-antigen (HBeAg), hepatitis B e-antibody (anti-HBe), hepatitis B surface antibody (anti-HBs) and HBV DNA, and biochemical tests were basically conducted every 4 weeks for at least 24 weeks. Result: The average cut-off index of HBsAg was 8.7 ± 9.6 (range, 1.0–25.7). All the patients were negative for anti-HBc, HBeAg, anti-HBe and HBV DNA on their initial visit. The genotype of HBV could be determined in four patients: two were infected with genotype B/HBV, one was infected with genotype A/HBV, and the remaining patient was infected with genotype C/HBV. Although HBsAg clearance was observed within 4 months in all the patients, none of the other HBV markers seroconverted during the observation period. Conclusion: HBV infection terminating with seronegativity for HBV markers may occur in transient HBV infection. 相似文献
99.
The effects of aging on the central nervous system steroid profiles and myelin basic protein in rats
Ciftci G Yarim GF Yarim M Karayigit MO Cenesiz S Nisbet C Gultiken ME 《Aging clinical and experimental research》2012,24(2):117-124
The aim of this study was to investigate the effects of aging on the central nervous system steroid and myelin basic protein (MBP) profiles. Forty-seven male Sprague-Dawley rats (newborn, 1, 6, 12 and 24-monthsold) were studied. Tissues were obtained from the cerebellum and parietal, frontal, temporal cortex of the central nervous system of the rats for steroid extraction. The estradiol, progesteron, testosterone and dehydroepiandrosterone (DHEA) levels were measured by Enzyme Linked Immunosorbent Assay (ELISA). The average levels of estradiol (pg/g), progesteron (ng/g), DHEA (ng/g) and testosterone (ng/g) in the brain tissues were respectively 24.29, 4.59, 0.27, 0.92 in the newborn-rats; 4.18 ± 1.10, 1.54 ± 0.30, 0.28 ± 0.01, 0.57 ± 0.10 in the 1 month-old-rats; 11.02 ± 1.10, 2.96 ± 0.30, 0.27 ± 0.01, 0.61 ± 0.10 in the 6 month-old-rats; 15.80 ± 1.10, 4.80 ± 0.30, 0.28 ± 0.10, 0.67 ± 0.10 in the 12 monthold- rats; 20.07 ± 1.10, 4.12 ± 0.30, 0.28 ± 0.01, 0.55±0.10 in the 24 month-old-rats. The myelin basic protein levels were determined by immunohistochemical staining and an elevation was observed in conjunction with the aging process. The results of the study indicate that the alterations in MBP, DHEA, progesterone, testosterone and estrodiol concentrations in the central nervous system of the rats during aging can be considered fundamental for future animal and human studies. 相似文献
100.
Kotaro Satake Tokumi Kanemura Akiyuki Matsumoto Hidetoshi Yamaguchi Yoshimoto Ishikawa 《European spine journal》2013,22(8):1854-1858