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651.
The neural substrate of gesture recognition   总被引:1,自引:0,他引:1  
Previous studies have linked action recognition with a particular pool of neurons located in the ventral premotor cortex, the posterior parietal cortex and the superior temporal sulcus (the mirror neuron system). However, it is still unclear if transitive and intransitive gestures share the same neural substrates during action-recognition processes. In the present study, we used event-related functional magnetic resonance imaging (fMRI) to assess the cortical areas active during recognition of pantomimed transitive actions, intransitive gestures, and meaningless control actions. Perception of all types of gestures engaged the right pre-supplementary motor area (pre-SMA), and bilaterally in the posterior superior temporal cortex, the posterior parietal cortex, occipitotemporal regions and visual cortices. Activation of the posterior superior temporal sulcus/superior temporal gyrus region was found in both hemispheres during recognition of transitive and intransitive gestures, and in the right hemisphere during the control condition; the middle temporal gyrus showed activation in the left hemisphere when subjects recognized transitive and intransitive gestures; activation of the left inferior parietal lobe and intraparietal sulcus (IPS) was mainly observed in the left hemisphere during recognition of the three conditions. The most striking finding was the greater activation of the left inferior frontal gyrus (IFG) during recognition of intransitive actions. Results show that a similar neural substrate, albeit, with a distinct engagement underlies the cognitive processing of transitive and intransitive gestures recognition. These findings suggest that selective disruptions in these circuits may lead to distinct clinical deficits.  相似文献   
652.
The relative contribution of each sex steroid (i.e. estrogen and androgen) on bone in men and the relationships among sex steroids and changes in BMD and bone strength are still unknown. A defective BMD of bone tissue is constantly present in men with aromatase deficiency. This study evaluates the effects of different regimens of treatment with sex steroids over 7.3 years follow-up on BMD in an adult man affected by aromatase deficiency and by a concomitant mild hypogonadism, as previously described. The aim of the study is to provide additional data on the relative roles of androgens and estrogens in male bone metabolism. The effects of testosterone (T) treatment alone and estrogen (tE2) treatment alone as well as the effects of the combined treatment with testosterone and estradiol (T plus tE2) on areal BMD (aBMD) at dual-energy X-ray absorptiometry (DXA) and the effects of T plus tE2 on volumetric BMD (vBMD), particular at cortical site, measured by peripheral quantitative computed tomography (pQCT), are investigated. Hormones and markers of bone turnover were monitored during all phases of the study. Treatment with tE2 normalized serum estradiol, but only the combined treatment with T plus tE2 normalized both serum estradiol and testosterone. Markers of bone turnover reached a pattern close to normality during T plus tE2. The aBMD was little modified by T, but increased more during tE2. T plus tE2 resulted in a further increase in both aBMD at DXA and vBMD at pQCT. Cortical thickness increased during T plus tE2 both in radius and tibia. Only the combined treatment led to optimal parameters of aBMD suggesting that testosterone needs estrogens as a permissive factor for a direct androgen anabolic action on bone in men.  相似文献   
653.
In a prospective, open-label study, 25 patients with mild-to-moderate type 1 Gaucher's disease (GD1) were treated with miglustat (Zavesca), an oral glucosylceramide synthase inhibitor, over 12 months. Of the 25 patients, 10 were therapy-na?ve and 15 had previously received enzyme replacement therapy (ERT). Clinical status, blood parameters, biomarkers, and organomegaly were assessed at baseline at 6 months and at 12 months. At 6 months the previously untreated patients showed a mean increase in hemoglobin of 0.77 g/dL, platelet counts improved or remaining stable, chitotriosidase and CCL18 decreased. These results were similar to those observed in 40 Spanish GD1 patients on ERT. Bone marrow infiltration cleared at 12 months. In the previously treated group, clinical and hematologic parameters and biomarkers were maintained/ improved at 12 months. Miglustat was well tolerated. The efficacy of miglustat treatment after 6 months was comparable to that of ERT.  相似文献   
654.
Oral Diseases (2010) 16 , 185–187 Aim: The aim of this study was to establish the impact of the redefinition and reclassification of odontogenic keratocyst (OKC) as a tumour on the prevalence of odontogenic tumours (OT). Methods: We revised 15 435 files of a teaching head and neck histopathology service in the time period from January 1981 to December 2008 and 478 cases of OT were selected. The 342 cases from 1981 to 2004 were classified according 1992 to the World Health Organization (WHO)‐classification (excluding keratocystic OT) while the 136 cases from 2005 onwards were classified according to the 2005 WHO‐classification (including keratocystic OT). Age and gender were obtained from medical records. The frequency distribution and prevalence of OT from each periods of time were compared. A chi‐square test was performed (P < 0.05 95% confidence interval). Results: The prevalence of OT increases 92% in the 2005–2008 period; from 2.6% (1981–2004 period) to 5% (2005–2008 period) (P 0.000).The most frequent OT in the 1981–2004 period was odontoma (45% of all OT) while in the 2005–2008 period was Keratocystic Odontogenicv Tumour (38.9%). Conclusions. The redefinition of OKC as a tumour produced an increase in the frequency and prevalence of OT.  相似文献   
655.
Cox  N. J.  Lim  S. ER  Howson  F.  Moyses  H.  Ibrahim  K.  Sayer  A. A.  Roberts  H. C.  Robinson  S. M. 《The journal of nutrition, health & aging》2020,24(10):1107-1110
The journal of nutrition, health & aging - Appetite loss is common in hospitalised older individuals but not routinely assessed. Poor appetite in hospital has previously been identified as...  相似文献   
656.
Background/aim This study was conducted to elucidate the effects of lutein/zeaxanthin isomers (L/Zi) on lipid metabolism, oxidative stress, NF-κB/Nrf2 pathways, and synaptic plasticity proteins in trained rats.Materials and methods Wistar rats were distributed into four groups: 1) control, 2) L/Zi: rats received L/Zi at the dose of 100 mg/kg by oral gavage, 3) exercise, 4) exercise+L/Zi: rats exercised and received L/Zi (100 mg/kg) by oral gavage. The duration of the study was eight weeks. Results Exercise combined with L/Zi reduced lipid peroxidation and improved antioxidant enzyme activities of muscle and cerebral cortex in rats (p < 0.001). In the Exercise + L/Zi group, muscle and cerebral cortex Nrf2 and HO-1 levels increased, while NF-κB levels decreased (p <0.001). Also, L/Zi improved BDNF, synapsin I, SYP, and GAP-43 levels of the cerebral cortex of trained rats (p < 0.001). The highest levels of BDNF, synapsin SYP, and GAP-43 in the cerebral cortex were determined in the Exercise+L/Zi group.Conclusion These results suggested that exercise combined with L/Zi supplementation might be effective to reduce neurodegeneration via improving neurotrophic factors and synaptic proteins, and oxidative capacity in the cerebral cortex.  相似文献   
657.
Background/aimTo investigate the changes in the spleen size, parenchymal heterogeneity, and computed tomography (CT) texture analysis features of patients diagnosed with Coronavirus disease 2019 (COVID-19)Materials and methodsThe size and parenchymal structure of the spleen in 91 patients who underwent thoracic CT examination due to COVID-19 were evaluated. For the evaluation of parenchymal heterogeneity, CT texture analysis was performed using dedicated software (Olea Medical, France). The texture analysis of each case consisted of 15 first-order intensity-based features, 17 gray level co-occurrence matrix-based features, and 9 gray level run length matrix-based features.ResultsA total of 91 patients (45 males, 46 females) with a mean age of 54.31 ± 16.33 years (range: 18–81) were included in the study. A statistically significant decrease in spleen size was seen in the follow-up CT examinations (p < 0.001) whereas no statistically significant difference was found between the Hounsfield unit (HU) values. The radiomics consisted of first-order intensity-based features such as 90th percentile, maximum, interquartile range, range, mean absolute deviation, standard deviation, and variance, all of which showed statistically significant differences (p - values: < 0.001, < 0.001, 0.001, 0.003, 0.001, 0.001, and 0.004, respectively). “Correlation” as a gray level co-occurrence matrix-based feature and “gray level nonuniformity” as a gray level run length matrix-based feature showed statistically differences (p-values: 0.033 and < 0.001, respectively).ConclusionsAlthough COVID-19 manifests with lung involvement in the early stage, it can also cause systemic involvement, and the spleen may be one of its target organs. A decrease in the spleen size and parenchymal microstructure changes can be observed in the short follow-up time. It is hoped that the changes in the parenchymal microstructure will be demonstrated by a noninvasive method: texture analysis.  相似文献   
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