水温对金鱼和神仙鱼呼吸频率的比较研究

在饲养水温为28℃、25℃、22℃、19℃、16℃时,水温对金鱼和神仙鱼的呼吸频率的影响均呈线性关系,其回归方程分别为Y=2.622X+43.911(R=0.853)和Y=5.178X-8.994(R=0.827),水温变化对神仙鱼呼吸频率的影响比金鱼明显。另外,28℃与25℃、25℃与22℃时金鱼和神仙鱼的呼吸频率差异不显著(P>0.05),而水温22℃与19℃、19℃与16℃的比较均差异显著(P<0.05)。     

Probiotics supplementation for athletes – Clinical and physiological effects

Abstract

Probiotic supplementation has traditionally focused on gut health. However, in recent years, the clinical applications of probiotics have broadened to allergic, metabolic, inflammatory, gastrointestinal and respiratory conditions. Gastrointestinal health is important for regulating adaptation to exercise and physical activity. Symptoms such as nausea, bloating, cramping, pain, diarrhoea and bleeding occur in some athletes, particularly during prolonged exhaustive events. Several studies conducted since 2006 examining probiotic supplementation in athletes or highly active individuals indicate modest clinical benefits in terms of reduced frequency, severity and/or duration of respiratory and gastrointestinal illness. The likely mechanisms of action for probiotics include direct interaction with the gut microbiota, interaction with the mucosal immune system and immune signalling to a variety of organs and systems. Practical issues to consider include medical and dietary screening of athletes, sourcing of recommended probiotics and formulations, dose–response requirements for different probiotic strains, storage, handling and transport of supplements and timing of supplementation in relation to travel and competition.     

鸡传染性喉气管炎的防治

鸡传染性喉气管炎（Infectious Laryngotracheitis,ILT）是由疱疹病毒属A亚群病毒感染而引发的一种急性呼吸道传染性疾病。该病具有传染性快、死亡率高、淘汰率高等特点,给家禽育种和养殖带来了非常严重的经济损失。迄今为止,对该病的防治尚无有效的方法。借鉴广大兽医工作者丰富的临床禽病治疗经验,结合自身的实践,笔者提出了一套ILT的综合防治方案。该方案在养殖实践中取得了较好的效果。     

Development and validation of an individualized nomogram for early prediction of the duration of SARS-CoV-2 shedding in COVID-19 patients with non-severe disease

With the number of cases of coronavirus disease-2019(COVID-19) increasing rapidly, the World Health Organization(WHO) has recommended that patients with mild or moderate symptoms could be released from quarantine without nucleic acid retesting, and self-isolate in the community. This may pose a potential virus transmission risk. We aimed to develop a nomogram to predict the duration of viral shedding for individual COVID-19 patients. This retrospective multicentric study enrolled 135 patients as a training cohort and 102 patients as a validation cohort. Significant factors associated with the duration of viral shedding were identified by multivariate Cox modeling in the training cohort and combined to develop a nomogram to predict the probability of viral shedding at 9, 13, 17, and 21 d after admission. The nomogram was validated in the validation cohort and evaluated by concordance index(C-index), area under the curve(AUC), and calibration curve. A higher absolute lymphocyte count(P=0.001) and lymphocyte-to-monocyte ratio(P=0.013) were correlated with a shorter duration of viral shedding, while a longer activated partial thromboplastin time(P=0.007) prolonged the viral shedding duration. The C-indices of the nomogram were 0.732(95% confidence interval(CI): 0.685-0.777) in the training cohort and 0.703(95% CI: 0.642-0.764) in the validation cohort. The AUC showed a good discriminative ability(training cohort: 0.879, 0.762, 0.738, and 0.715 for 9, 13, 17, and 21 d; validation cohort: 0.855, 0.758, 0.728, and 0.706 for 9, 13, 17, and 21 d), and calibration curves were consistent between outcomes and predictions in both cohorts. A predictive nomogram for viral shedding duration based on three easily accessible factors was developed to help estimate appropriate self-isolation time for patients with mild or moderate symptoms, and to control virus transmission.     

Comparison of COVID-19 and influenza characteristics

The emergence of coronavirus disease 2019(COVID-19) not only poses a serious threat to the health of people worldwide but also affects the global economy. The outbreak of COVID-19 began in December 2019, at the same time as the influenza season. However, as the treatments and prognoses of COVID-19 and influenza are different, it is important to accurately differentiate these two different respiratory tract infections on the basis of their respective early-stage characteristics. We reviewed official documents and news released by the National Health Commission of the People's Republic of China, the Chinese Center for Disease Control and Prevention(China CDC), the United States CDC, and the World Health Organization(WHO), and we also searched the PubMed, Web of Science, Excerpta Medica database(Embase), China National Knowledge Infrastructure(CNKI), Wanfang, preprinted bioRxiv and medRxiv databases for documents and guidelines from earliest available date up until October 3 rd, 2020. We obtained the latest information about COVID-19 and influenza and summarized and compared their biological characteristics, epidemiology, clinical manifestations, pathological mechanisms, treatments, and prognostic factors. We show that although COVID-19 and influenza are different in many ways, there are numerous similarities;thus, in addition to using nucleic acid-based polymerase chain reaction(PCR) and antibody-based approaches, clinicians and epidemiologists should distinguish between the two using their respective characteristics in early stages. We should utilize experiences from other epidemics to provide additional guidance for the treatment and prevention of COVID-19.     

我国国家游泳集训队队员身体形态、呼吸机能及发育水平分析

为准确了解现阶段我国优秀游泳运动员的身体形态特点,特对2006年我国国家游泳集训队125名队员的身体长度、宽度、围度、皮褶厚度等28个形态指标和肺活量、一维重心、骨骼年龄3个指标进行了测试。测试发现：2006年集训队队员的体型更趋于游泳项目所要求的水中减阻的流线型体征;但队员躯干围度指标的发展趋势不利于降低形态阻力,提醒应通过有针对性的训练加以改善。男队员身体长度及其复合指标整体上均好于2004年队员;2006年队员的上臂肌力与呼吸机能有所下降;一维重心与未成年队员骨龄的测量,能为早期重点培养运动员提供科学依据。     

气体代谢指标监测健身快走能量消耗的实验研究

目的：通过测量健身快走运动中能量消耗特征揭示其变化情况,为大学生健身效果评价提供依据。方法：8名普通男大学生以6.5km/h匀速进行60min快走运动,采用气体代谢法测定并推算机体能量消耗状况。结果：1）25min时糖和脂肪二者供能百分比分别为50.7%、49.3%。2）脂肪供能量45min后快速增加,60min时值最高,糖供能量逐渐下降,结束为（1.47±0.57）Kcal/min·kg。3）糖氧化量前10min缓慢增长后减少,结束值为（0.29±0.12）g/min·kg,脂肪氧化量30min后快速提高,结束值为（0.87±0.06）g/min·kg,40min-45min出现均衡,为0.79g/min·kg。结论：1）25min时糖脂肪供能百分比形成交叉。2）供能百分比、供能量、氧化量随时间延长脂肪均大于糖。3）从能量代谢和底物代谢角度看,6.5km/h速度进行60min快走属中等强度,从长时间健身走供能关系来说对大学生健身有积极作用。     

Factors associated with a SARS-CoV-2 recurrence after hospital discharge among patients with COVID-19: systematic review and meta-analysis

Background: The proportion of recurrences after discharge among patients with coronavirus disease 2019 (COVID-19) was reported to be between 9.1% and 31.0%. Little is known about this issue, however, so we performed a meta-analysis to summarize the demographical, clinical, and laboratorial characteristics of non-recurrence and recurrence groups. Methods: Comprehensive searches were conducted using eight electronic databases. Data regarding the demographic, clinical, and laboratorial characteristics of both recurrence and non-recurrence groups were extracted, and quantitative and qualitative analyses were conducted. Results: Ten studies involving 2071 COVID-19 cases were included in this analysis. The proportion of recurrence cases involving patients with COVID-19 was 17.65% (between 12.38% and 25.16%) while older patients were more likely to experience recurrence (weighted mean difference (WMD)=1.67, range between 0.08 and 3.26). The time from discharge to recurrence was 13.38 d (between 12.08 and 14.69 d). Patients were categorized as having moderate severity (odds ratio (OR)=2.69, range between 1.30 and 5.58), while those with clinical symptoms including cough (OR=5.52, range between 3.18 and 9.60), sputum production (OR=5.10, range between 2.60 and 9.97), headache (OR=3.57, range between 1.36 and 9.35), and dizziness (OR=3.17, range between 1.12 and 8.96) were more likely to be associated with recurrence. Patients presenting with bilateral pulmonary infiltration and decreased leucocyte, platelet, and CD4⁺ T counts were at risk of COVID-19 recurrence (OR=1.71, range between 1.07 and 2.75; WMD=−1.06, range between −1.55 and −0.57, WMD=−40.39, range between −80.20 and −0.48, and WMD=−55.26, range between −105.92 and −4.60, respectively). Conclusions: The main factors associated with the recurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after hospital discharge were older age, moderate severity, bilateral pulmonary infiltration, laboratory findings including decreased leucocytes, platelets, and CD4⁺ T counts, and clinical symptoms including cough, sputum production, headache, and dizziness. These factors can be considered warning indicators for the recurrence of SARS-CoV-2 and might help the development of specific management strategies.     

运动与病毒性感染疾病的关系

一次力竭性运动或持续超大强度训练均可增加机体上呼吸道感染和其他病毒性感染的易感性,但不影响机体对细菌性感染的抵抗力。大强度训练对T细胞-白细胞介素-NK细胞系统具有抑制效应,且效应可持续1周以上。相反,适度训练则能增强免疫功能。鉴于急性病毒感染对运动能力和精神面貌的负性影响,加之伴随病毒性心肌炎而偶发的急性死亡事件,所以应尽量降低运动员病毒性感染的发生率。坚持预防注射程序、减少感染暴露、避免超大强度训练、保证合理饮食、减轻心理和环境压力等,都是可采用的措施。     

《国家学生体质健康标准》中大学生心血管机能评价指标有效性的实验研究

为了分析<国家学生体质健康标准>中心台阶试验作为有氧耐力素质指标的有效性,对358名普通大学生进行体质健康测试和最大吸氧量测试.研究结果表明:大学生最大吸氧量与台阶试验测试值和台阶试验得分无显著线性相关(r=0.015,P>0.05),<国家学生体质健康标准>中台阶试验不能作为评价大学生心血管功能和机体有氧工作能力的有效指标;男、女大学生台阶指数分别为46.53和47.30,男女生的台阶指数之间存在显著差异(P<0.05);男女大学生平均最大吸氧量分别为50.85 ml/kg.min和35.03 ml/kg.min,男女大学生最大吸氧量差异显著(P<0.01);大学生最大吸氧量与其肺活量指数之间呈一定的相关关系.