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The COVID-19 pandemic has presented significant challenges and implications for the sports community. Thus, this study aimed to describe the prevalence of COVID-19 in Brazilian athletes and identify the epidemiological, clinical, athletic, life and health factors associated with the disease in these individuals. A cross-sectional study was performed involving 414 athletes from 22 different sports using an online questionnaire from August to November 2020. The association between the athletes’ characteristics and COVID-19 was evaluated using a logistic regression model. The prevalence of COVID-19 was 8.5%, although only 40% of athletes reported having been tested. Being under 27 years of age (3-fold), having children (~5-fold), having a teammate test positive for COVID-19 (2.5-fold), and smoking (14-fold) were associated with a possible higher risk of disease. Almost 20% of athletes self-reported musculoskeletal injuries during the period of the pandemic that was studied. Athletes with a university education (P = 0.02), a profession other than sports (P < 0.001), those from a low-income family (P = 0.01), and public health system users (P = 0.04) were significantly less frequently tested for COVID-19, whereas international competitors, athletes who received a wage, and athletes who had a teammate who tested positive for COVID-19 were 2-, 3-, and 15-fold more likely to be tested for COVID-19, respectively. Approximately 26% of the athletes who tested negative or were untested reported more than three characteristic COVID-19 symptoms, and 11% of athletes who tested positive for COVID-19 were asymptomatic. The identification of modifiable (have children, smoking, and teammates positively tested) and non-modifiable (age under 27 years) factors related to COVID-19 in athletes can contribute to implementing surveillance programmes to decrease the incidence of COVID-19 in athletes and its negative impacts in sports.  相似文献   
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1. Rapid expansion and intensification of anthropogenic activities in the 20th century has caused profound changes in freshwater assemblages. Unfortunately, knowledge of the extent and causes of species loss (SL) is limited due to the lack of reliable historical data. An unusual data set allows us to compare changes in the most sensitive of aquatic insect orders, the Plecoptera, at some 170 locations in the Czech Republic between two time periods, 1955–1960 and 2006–2010. Historical data (1890–1911) on assemblages of six lowland rivers allow us to infer even earlier changes. 2. Regional stonefly diversity decreased in the first half of the 20th century. Streams at lower altitudes lost a substantial number of species, which were never recovered. In the second half of the century, large‐scale anthropogenic pressure caused SL in all habitats, leading to a dissimilarity of contemporary and previous assemblages. The greatest changes were found at sites affected by organic pollution and a mixture of organic pollution and channelisation or impoundment. Colonisation of new habitats was observed in only three of the 80 species evaluated. 3. Species of moderate habitat specialisation and tolerance to organic pollution were most likely to be lost. Those with narrow specialisations in protected habitats were present in both historical and contemporary collections. 4. Contemporary assemblages are the consequence of more than a 100 years of anthropogenic impacts. In particular, streams at lower altitude and draining intensively exploited landscapes host a mere fragment of the original species complement. Most stonefly species are less frequently present than before, although their assemblages remain almost intact in near‐natural mountain streams. Our analyses demonstrate dramatic restriction of species ranges and, in some cases, apparent changes in altitudinal preference throughout the area.  相似文献   
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We examined the effect of fatigue of the quadriceps muscles on coactivation of the hamstring muscles and determined if the response is different between two isokinetic speeds in ten males and ten females with no history of knee pathology. Electromyographic data were recorded from the vastus lateralis and biceps femoris muscles during 50 maximal knee extensions at isokinetic speeds of 1.75 rad · s−1 (100° · s−1) and 4.36 rad · s−1 (250° · s−1). A greater degree of coactivation was apparent at the higher speed, but the increase in coactivation of the hamstring muscles was similar at both speeds. The results revealed that: (1) coactivation is greater at a higher isokinetic speed, and (2) coactivation increases during fatigue, but the rate of increase is independent of contraction velocity. Accepted: 15 June 1998  相似文献   
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Objectives: This study investigated the potential anti-inflammatory effect of hesperidin against carrageenan induced pleurisy in rat model.

Methods: Twenty-four adult female Wistar rats (350 - 450g) were grouped as follows: Group I: rats were administered saline solution only (Normal control group); Group II: rats were administered saline solution (NaCl 0.9%) orally and injected with carrageenan (Inflammation control group); Group III: rats were administered hesperidin only (Hesperidin group); Group IV: rats were administered hesperidin orally and intrapleurally injected with 2% carrageenan (Inflammation treated with hesperidin group). The exudate volume, total leukocyte count, reactive oxygen species (ROS), myeloperoxidase (MPO),δ–aminolevulinate dehydratase (δ-ALA-D), catalase (CAT), superoxide dismutase (SOD), activities as well as non-protein thiol group (NPSH) and thiobarbituric acid reactive substances (TBARS) levels were determined.

Results: Pretreatment with hesperidin at a dose of 80 mg/kg orally per day for 21 days, minimized the increase in pleural exudate volume and leucocyte count and modulated the activities of MPO, SOD and CAT, as well as the levels of ROS, NPSH and TBARS in carrageenan-induced rats.

Conclusion: Our results suggest that hesperidin can elicit its anti-inflammatory action by blocking exudate and leukocyte influx into pleural cavity, inhibiting MPO activity and preventing oxidative damage.  相似文献   

36.
Urban pollution of riverine ecosystem is a serious concern in the Niger Delta region of Nigeria. No biomonitoring tool exists for the routine monitoring of effects of urban pollution on riverine systems within the region. Therefore, the aim of this study was to develop and apply a macroinvertebrate‐based multimetric index for assessing water quality condition of impacted urban river systems in the Niger Delta region of Nigeria. Macroinvertebrate and physicochemical samples were collected from 11 stations in eight river systems. Based on the physicochemical variables, the stations were categorized into three impact categories namely least impacted stations (LIS), moderately impacted stations (MIS) and heavily impacted stations (HIS). Seventy‐seven (77) candidate metrics were tested and only five: Hemiptera abundance, %Coleoptera + Hemiptera, %Chironomidae + Oligochaeta, Evenness index and Logarithm of relative abundance of very large body size (>40–80 mm) were retained and integrated into the final Niger Delta urban multimetric index (MINDU). The validation dataset showed a correspondence of 83.3% between the index result and the physicochemically‐based classification for the LIS and a 75% correspondence for the MIS. A performance of 22.2% was recorded for the HIS. The newly developed MINDU proved useful as a biomonitoring tool in the Niger Delta region of Nigeria and can thus be used by environmental managers and government officials for routine monitoring of rivers and streams subjected to urban pollution.  相似文献   
37.
Inhibitory interneurons mediate the gating of synaptic transmission and modulate the activities of neural circuits. Disruption of the function of inhibitory networks in the forebrain is linked to impairment of social and cognitive behaviors, but the involvement of inhibitory interneurons in the cerebellum has not been assessed. We found that Cadherin 13 (Cdh13), a gene implicated in autism spectrum disorder and attention‐deficit hyperactivity disorder, is specifically expressed in Golgi cells within the cerebellar cortex. To assess the function of Cdh13 and utilize the manipulation of Cdh13 expression in Golgi cells as an entry point to examine cerebellar‐mediated function, we generated mice carrying Cdh13‐floxed alleles and conditionally deleted Cdh13 with GlyT2::Cre mice. Loss of Cdh13 results in a decrease in the expression/localization of GAD67 and reduces spontaneous inhibitory postsynaptic current (IPSC) in cerebellar Golgi cells without disrupting spontaneous excitatory postsynaptic current (EPSC). At the behavioral level, loss of Cdh13 in the cerebellum, piriform cortex and endopiriform claustrum have no impact on gross motor coordination or general locomotor behaviors, but leads to deficits in cognitive and social abilities. Mice lacking Cdh13 exhibit reduced cognitive flexibility and loss of preference for contact region concomitant with increased reciprocal social interactions. Together, our findings show that Cdh13 is critical for inhibitory function of Golgi cells, and that GlyT2::Cre‐mediated deletion of Cdh13 in non‐executive centers of the brain, such as the cerebellum, may contribute to cognitive and social behavioral deficits linked to neurological disorders.  相似文献   
38.
IntroductionHealth financing reforms in low- and middle- income countries (LMICs) over the past decades have focused on achieving equity in financing of health care delivery through universal health coverage. Benefit and financing incidence analyses are two analytical methods for comprehensively evaluating how well health systems perform on these objectives. This systematic review assesses progress towards equity in health care financing in LMICs through the use of BIA and FIA.ConclusionStudies evaluated in this systematic review indicate that health care financing in LMICs benefits the rich more than the poor but the burden of financing also falls more on the rich. There is some evidence that primary health care is pro-poor suggesting a greater investment in such services and removal of barriers to care can enhance equity. The results overall suggest that there are impediments to making health care more accessible to the poor and this must be addressed if universal health coverage is to be a reality.  相似文献   
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We describe here a molecular genetic approach for imaging synaptic inhibition. The thy-1 promoter was used to express high levels of Clomeleon, a ratiometric fluorescent indicator for chloride ions, in discrete populations of neurons in the brains of transgenic mice. Clomeleon was functional after chronic expression and provided non-invasive readouts of intracellular chloride concentration ([Cl(-)](i)) in brain slices, allowing us to quantify age-dependent declines in resting [Cl(-)](i) during neuronal development. Activation of hippocampal interneurons caused [Cl(-)](i) to rise transiently in individual postsynaptic pyramidal neurons. [Cl(-)](i) increased in direct proportion to the amount of inhibitory transmission, with peak changes as large as 4 mM. Integrating responses over populations of pyramidal neurons allowed sensitive detection of synaptic inhibition. Thus, Clomeleon imaging permits non-invasive, spatiotemporally resolved recordings of [Cl(-)](i) in a large variety of neurons, opening up new opportunities for imaging synaptic inhibition and other forms of chloride signaling.  相似文献   
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