不同训练负荷太极拳运动对早中期帕金森病患者康复疗效

目的 通过对比对照组和太极拳运动组，评价太极拳运动在早中期帕金森病患者康复作用。方法 45例帕金森病患者随机分为：对照组（n=15），不接受干预；太极拳1组（n=15）采用24式简化太极拳练习，40 min/次，3次/周；太极拳2组（n=15）采用24式简化太极拳练习，60 min/次，3次/周。在基线、12周、24周运动后采用患者跌倒功效量表（FES）、起立-行走计时测试（TUGT）、Berg平衡量表评分（BBS）、统一帕金森病评定量表（UPDRS） Ⅲ评分、汉密尔顿焦虑抑郁量表评分（HAMD、HAMA）、匹兹堡睡眠质量指数评分（PSQI）进行评估。结果 太极拳1组，24周对比基线在TUGT、BBS评分的改善上有统计学意义（P<0.05）。太极拳2组，24周对比基线在TUGT、 BBS评分的改善上有统计学意义（P<0.05）,24周对比12周在TUGT的改善上有统计学意义（P<0.05）。结论 太极拳运动可以改善早中期帕金森病患者的平衡障碍，可降低跌倒风险。     

Salmon‐derived nutrients drive diatom beta‐diversity patterns

1. Pacific salmon are a textbook example of migratory animals that transfer nutrients between ecosystems, but little is known about how salmon‐derived nutrients (SDN) affect the biodiversity of recipient freshwater ecosystems. We examined paleolimnological records from six Alaskan lakes to define how changes in SDN from sockeye salmon (Oncorhynchus nerka) influenced sedimentary diatom community structure and beta‐diversity among lakes and through time. 2. Using an isotopic mixing model, we showed that SDN loading could account for >80% of the lake total nitrogen budgets and strongly regulated diatom community composition. Spatial dissimilarity in diatom communities was positively related to differences in SDN among lakes (r² = 0.69, P < 0.01, n = 10). Likewise, temporal dissimilarity in diatom communities was positively related to differences in SDN in a sediment core with substantial variation in salmon spawner dynamics between 1700 and 1950 AD (r² = 0.34, P < 0.01, n = 19). Finally, beta‐diversity metrics quantifying temporal turnover within each lake’s sediment record were also positively related to the variance in SDN loading among lakes (r² = 0.88, P < 0.05, n = 5). Mean SDN was only negatively correlated to temporal diatom beta‐diversity. 3. Spatially subsidised systems often receive temporally variable resource inputs, and thus, it is not surprising that, unlike previous studies, we found that resource variability was the key driver of community composition and beta‐diversity. In habitats that receive strongly fluctuating external nutrient loads, environment heterogeneity may overweigh stochastic community processes. In addition, freshwater diatoms are characterised by great dispersal capabilities and short life cycles and therefore may be a more sensitive indicator for evaluating the role of resource variability than previously used model organisms. These results suggest that productivity–diversity relationship vary with the nature of nutrient loading and the life history of the community studied. 4. Overall, our study highlights that the transport of nutrients by sockeye salmon across ecosystem boundaries is a significant driver of algal community and biodiversity in nursery lakes, mainly through changing the magnitude of nutrient variation. As such, freshwater species diversity in regions like the U.S. Pacific Northwest may become impoverished where there have been long‐term declines in salmon populations and decreases in nutrient variability among lakes.