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BackgroundThree-dimensional (3D) motion measured at the lower back during walking can describe the regularity and symmetry of gait that may be related to osteoarthritis (OA) and functional status. However, gait speed and inherent sex differences, regardless of the presence of OA, may confound these measures. Therefore, there is a need to understand the effect of OA separately among males and females, without the confounding influence of gait speed.ObjectiveTo investigate the difference in 3D gait regularity and symmetry measures between gait speed-matched males and females with and without knee OA.MethodGait regularity and symmetry were computed as autocorrelations of pelvic accelerations during treadmill walking in four groups of older adults: healthy asymptomatic females (AsymF; n = 44), healthy asymptomatic males (AsymM; n = 45), females diagnosed with knee OA (OAF; n = 44), and males diagnosed with knee OA (OAM; n = 45). Data were obtained from a larger research database, allowing for the matching of gait speed between groups. The main effect of OA, sex, and interaction effect between them was examined for the 3D gait regularity and symmetry measures at an alpha level of 0.05.ResultsThere was no main effect of OA on any variable, but there was a significant main effect of sex on mediolateral and anteroposterior gait regularity measures. Specifically, females demonstrated significantly greater gait regularity, most notably in the mediolateral directions compared to males.ConclusionOlder adult females were found to display significantly greater mediolateral gait regularity as compared to males, regardless of the presence of OA. Further, this difference exists among matched gait speeds, suggesting it is not the result of gait speed. Overall, these results highlight the importance of sex-specific analyses and considering gait speed when examining gait acceleration patterns near the center of mass for both cross sectional and longitudinal gait assessments.  相似文献   
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Both coronavirus disease 2019 (COVID?19) and severe acute respiratory syndrome (SARS) are epidemic, contagious, sudden, and publicly harmful diseases. The whole?genome nucleotide identity of the pathogens causing the two diseases reached 79.5%. The mechanism and treatment of COVID?19 are still under investigation. Combining the experiences of SARS prevention and treatment in 2003, and the case data and literature of COVID?19, the similarities and differences between the two diseases in terms of causes, susceptible people, characteristics, dialectical mode, and treatment were analyzed. The two diseases are both plagues in terms of Chinese medicine. The cause of SARS was “heat poison,” and its pathogenesis was “heat poison, stasis, and qi and yin deficiency.” Therefore the treatment regimen was mainly to clear away heat, detoxicate, and expel evil. While the cause of COVID?19 was “wet poison,” and its pathogenesis was “wet, poison, heat, stasis, close, syncope, and yang collapse.” Hence the basic treatment strategy was to declare lung and remove dampness. Treatment of COVID?19 was clearing away evil qi as soon as possible, with the basic treatment regimen, which was declaring lung, removing dampness, and dispelling the evil. Combined with Traditional Chinese medicine’s (TCM’s) understanding and experience in SARS prevention and treatment, and Chinese clinical cured cases, we try to provide strategies for people all over the world to understand and respond to COVID?19, through the analysis and comparison. To improve COVID-19 prevention and treatment regimen and give full play to the advantages of TCM.  相似文献   
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It has been widely demonstrated that there are a broad range of individual responses to all weight management regimens, often masked by reports of the mean. Identifying features of responders and non-responders to weight loss regimens enables a more tailored approach to the provision of weight management advice. Low-carbohydrate diets are currently popular, and anecdote suggests that males are more successful at losing weight using this approach. This is feasible given the physiological and socio-psychological differences between the genders. We analysed the extent and variation in weight change for males and females separately through a systematic search for all low-carbohydrate diet trials published since 1985. Very few studies compared weight loss outcomes by gender and, of those that did, most lacked supporting data. The majority of studies reported no gender difference but when a gender difference was found, males were more frequently reported as losing more weight than females on a low-carbohydrate diet. The lack of gender stratification in weight loss trials is concerning, as there are a range of gender-based factors that affect weight loss outcomes. This study highlights the importance of examining weight change for males and females separately, since as failure to do so may mask any potential differences, which, if detected, could assist with better weight loss outcomes.  相似文献   
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Collagen type II-induced arthritis (CIA) in Dark Agouti rats, a model of rheumatoid arthritis (RA), reproduces sexual dimorphism in the incidence and severity of the human disease. Th17 cells are central in the induction/propagation of autoimmune inflammation in CIA and RA. To assess mechanisms underlying this dimorphism in CIA rats, in lymph nodes draining inflamed joints and adjacent tissues (dLNs) from CIA rats of both sexes Th17/CD25+Foxp3+CD4+ T-regulatory cell (Treg) ratio, Th17 cell redifferentiation in functionally distinct subsets and Treg transdifferentiation into IL-17-producing cells (exTregs) were examined. In female rats (developing more severe CIA than their male counterparts) the higher frequency of all Th17 cells (reflecting partly their greater proliferation), followed by the higher frequency of highly pathogenic IFN-γ/GM-CSF-co-producing cells, but lower frequency of less pathogenic/immunoregulatory IL-10-producing cells among them was found. Additionally, compared with male rats, in female rats the lower frequency of Tregs was observed. Moreover, Tregs from female rats exhibited diminished proliferative and suppressive capacity (judging by PD-1 expression) and enhanced conversion into IL-17-producing cells. Given that TGF-β concentration was comparable in collagen-type II-stimulated dLN cell cultures from female and male rats, the shift in Th17/Treg ratio followed by augmented Th17 cell redifferentiation into IFN-γ/GM-CSF-co-producing cells and Treg transdifferentiation into IL-17-producing cells in female rats was associated with increased concentration of IL-6 in female rat dLN cell cultures, and the higher frequency of IL-1β- and IL-23-producing cells among their dLN cells. The lower frequency of IL-10-producing B cells, presumably B regulatory cells (Bregs) could also contribute to the shift in Th17/Treg ratio in female rat compared with male rat dLNs. Consistently, the lower expression of IL-35 (the cytokine promoting Treg expansion directly and indirectly, by favoring Breg expansion and conversion into IL-10/IL-35-producing cells) in female rat dLN cells was detected. Thus, the study identified putative cellular and molecular substrates of the sexual dimorphism in the immunopathogenesis and clinical outcome of CIA and suggested mechanisms to be targeted in females to improve control of Th17 response, and consequently clinical outcome of CIA, and possibly RA.  相似文献   
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Introduction: Both the neuropsychological study of patients with category-specific semantic disorders (CSSD) and the experimental research on categorical processing in healthy subjects (HSs) have shown that men are mainly impaired with fruits and vegetables and women with animals and artifacts. Since this difference is more striking in patients with CSSD than in HSs, we hypothesized that the lack of power of some investigations conducted with HSs and the different methods used in studies conducted with HSs and patients with CSSD could explain some of these inconsistencies and that a study conducted with a very large number of HSs using visual naming tasks should strongly confirm the role of gender in categorical tasks.

Methods: Picture naming data gathered during the last ten years with our category-specificity paradigm from a large number (702) of HSs were reanalyzed.

Results: As predicted, men named significantly more animals and artifacts, while women named more plant life items.

Discussion: These data confirm that, if different domains of knowledge are studied in a very large sample of HSs using a picture naming task equivalent to the naming tasks used in most anatomo-clinical studies on CSSD, then the gender effects are highly significant.  相似文献   

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