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81.
Severe and chronic stress may interfere with adolescent neuronal plasticity that turns the juvenile brain into an adult brain increasing the vulnerability to develop anxiety disorders. It is well-known from adult stress research that there is a large individual differentiation in stress vulnerability. The current study is aimed at the individual resilience and vulnerability to adolescent social stress. Two strains of rats that differ in social behavioral skills were subjected to social stress during adolescence. In three experiments we studied short and long term effects of adolescent social stress using a water conflict test in different contexts. Wistar rats which had been socially defeated on postnatal days 45 and 46 showed, following water deprivation, a strong decrease in the total amount of water consumed and time spent drinking when tested 2 days and 3 weeks later in the context where they received the defeat experience. Also a strong increase in drinking latency was noticed in the context of the previous defeat. No differences in these parameters were found between defeated and non-defeated wild-type rats. The results of the water conflict test in an environment where no association with the previous defeat experience was present showed that the adolescent social stress did not induce a generalized anxiety.In conclusion, the water conflict test is a useful tool to measure the influence of social defeat on the motivation to obtain resources under conditions with different stimulus properties. In addition, our data suggest the importance of the strain used in adolescent stress experiments. The fact that Wistar rats showed a strong association with the context at adulthood whereas no effect was observed in the wild-type rats shows that victim characteristics are important determining factors for the long term effects of adolescent social stress.  相似文献   
82.
Animals make behavioural and reproductive decisions that maximise their lifetime reproductive success, and thus their fitness, in light of periodic and stochastic variability of the environment. Modelling the variation of an individual's energy levels formalises this tradeoff and helps to quantify the population‐level consequences of stressors (e.g. disturbance from human activities and environmental change) that can affect behaviour or physiology. In this study, we develop a dynamic state variable model for the spatially explicit behaviour, physiology and reproduction of a female, long‐lived, migratory marine vertebrate. The model can be used to investigate the spatio‐temporal patterns of behaviour and reproduction that allow an individual to maximise its overall reproductive output. We parametrised the model for eastern North Pacific blue whales Balaenoptera musculus, and used it to predict the effects of changing environmental conditions and increasing human disturbance on the population's vital rates. In baseline conditions, the model output had high fidelity to observed energy dynamics, movement patterns and reproductive strategies. Simulated scenarios suggested that environmental changes could have severe consequences on the population's vital rates, but that individuals could tolerate high levels of anthropogenic disturbance. However, this ability depended on where, when and how often disturbance occurred. In scenarios with both environmental change and anthropogenic disturbance, synergistic interactions caused stronger effects than in isolation. In general, larger body size offered a buffer against stochasticity and disturbance, and, consequently, we predicted juveniles to be more susceptible to disturbance. We also predicted that females prioritise their own survival at the expense of the current reproductive attempt, presumably the result of their long lifespan. Our approach provides a general framework to make predictions of the cumulative and synergistic effects of human disturbance and climate change on migratory populations, which can inform effective management and conservation efforts.  相似文献   
83.
为分析综合护理干预对百草枯中毒患者临床治疗预后的效果,本研究选取2015年5月至2016年12月我院收治的百草枯中毒患者92例,根据护理方法不同分为对照组和观察组。对照组患者采用常规护理模式进行干预,观察组患者采用综合护理模式进行干预,分析两组患者护理后的效果。研究发现,观察组患者治愈率、7 d存活率和30 d存活率高于对照组,口腔黏膜愈合时间、住院时间短于对照组(p<0.05)。干预前,两组患者hs-CRP、IL-10、ASL、ALT水平比较无统计学差异(p>0.05)。干预后,观察组患者hs-CRP、IL-10、ASL、ALT水平低于对照组(p<0.05)。干预前,两组患者焦虑、抑郁评分比较无统计学差异(p>0.05)。干预后,观察组患者焦虑、抑郁评分低于对照组(p<0.05)。本研究的结果说明,百草枯中毒患者采用综合护理干预可加快患者口腔黏膜愈合时间,提高治愈率、存活率,改善患者心理状况,值得临床推广及进一步规范研究。  相似文献   
84.
目的:研究粪菌移植联合乳果糖对顽固性功能性便秘患者胃肠功能、生活质量及心理状态的影响。方法:选取2016年6月至2018年5月我院消化内科收治的顽固性功能性便秘患者100例为研究对象,按照随机数字表法将患者分为对照组(n=45)和研究组(n=55)。对照组给予乳果糖口服治疗,研究组则采用粪菌移植联合乳果糖治疗,两组均治疗6周。对比两组临床疗效、胃肠功能以及治疗前后生活质量和心理状态的变化,并观察两组治疗期间不良反应发生情况。结果:与对照组比较,研究组总有效率明显升高(P0.05)。研究组首次自主排便时间、肛门首次排气时间、肠鸣音恢复时间均短于对照组,胃肠减压引流量高于对照组(P0.05)。治疗6周后,两组患者生活质量自评量表(PAC-QOL)评分、Zung焦虑自评量表(SAS)评分和抑郁自评量(SDS)评分均较治疗前降低,且与对照组比较,研究组PAC-QOL评分、SAS评分、SDS评分均降低(P0.05)。两组不良反应发生率比较差异无统计学意义(P0.05)。结论:粪菌移植联合乳果糖对顽固性功能性便秘具有较好的疗效,可改善患者胃肠功能和心理状态,同时可提高患者生活质量,无严重不良反应发生。  相似文献   
85.
目的:探讨精神心理干预对慢性肛周湿疹患者治疗效果、心理健康及生活质量的影响,为临床治疗提供新的切入点。方法:选取122例慢性肛周湿疹患者为研究对象,采用随机数字表法分为干预组和对照组各61例。对照组接受常规治疗,干预组在对照组的基础上接受精神心理干预,两组患者均治疗8周。对比两组患者的临床疗效,观察并比较两组患者治疗前后的心理状态以及生活质量的变化情况。结果:干预组的总有效率为85.25%,明显高于对照组的62.30%(P0.05)。治疗8周后,两组患者焦虑自评量表(SAS)评分、抑郁自评量表(SDS)评分、皮肤病生活质量指数(DLQI)评分和匹兹堡睡眠质量指数(PSQI)评分均降低,且干预组患者治疗后的SAS评分、SDS评分、DLQI评分和PSQI评分均明显低于对照组(P0.05)。两组患者治疗后的心理弹性量表(CD-RISC)评分升高,且与对照组相比,干预组患者治疗后的CD-RISC评分显著升高(P0.05)。结论:精神心理干预联合常规治疗对慢性肛周湿疹具有较好的疗效。对患者实施精神心理干预可有效减轻患者焦虑、抑郁等负性情绪,提高患者心理韧性水平,促进患者生活质量的提升。  相似文献   
86.
国家自然科学基金委重大项目"禾本科植物的适应性辐射及其进化机制"利用比较形态学、分子系统学、进化发育生物学、古生物学等多方面证据,通过多学科交叉的方法探讨了禾本科植物中出现的适应性辐射现象及其机制,在禾本科的系统发育关系以及适应性辐射的基本式样、生物和非生物环境因素在物种适应和分化以及物种快速形成中的作用、基因组大小及其结构变异以及突变、重复和调控模式变化对适应性辐射过程中关键性状(功能)的影响等方面取得了重要进展,在人才培养、国际合作和实验体系建立等方面极具特点。该项目的顺利完成为更好地阐明植物多样性形成的原因与机理奠定了良好的基础。  相似文献   
87.
The purpose of the present study was to investigate the relation between adipose tissue polyunsaturated fatty acids, an index of long-term or habitual fatty acid dietary intake and depression. The sample consisted of 150 elderly males from the island of Crete. The subjects were survivors of the Greek Seven Countries Study group. The mean age was 84 years. The number of subjects with complete data on all variables studied was 63. Subjects were examined by the Preventive Medicine and Nutrition Clinic of the University of Crete. Depression was assessed through the use of the short form of the Geriatric Depression Scale (GDS-15). Depression correlated negatively with adipose tissue alpha-linolenic acid (C18:3n-3). Depressed subjects had significantly reduced (-10.5%) adipose tissue C18:3n-3 levels than non-depressed subjects. The observed negative relation between adipose tissue C18:3n-3 and depression, in the present study, appears to indicate increasing long-term dietary C18:3n-3 intakes with decreasing depression. This agrees with findings of other studies indicating an inverse relation between depression and consumption of fish and n-3 polyunsaturated fatty acids. This is the first literature report of a relation between adipose tissue C18:3n-3 and depression. Furthermore, this is the first report of a relation between adipose PUFA and depression in an elderly sample. Depression has been reported to be associated with elevated cytokines, such as, IL-1, IL-2, IL-6, INF-gamma and INF-alpha. Fish oil and omega-3 fatty acids, on the other hand, have been reported to inhibit cytokine production. The observed negative relation between adipose C18:3n-3 and depression, therefore, may stem from the inhibiting effect of C18:3n-3 or its long-chain metabolites on cytokine synthesis.  相似文献   
88.
Natural hybridization is widespread among coral reef fishes. However, the ecological promoters and evolutionary consequences of reef fish hybridization have not been thoroughly evaluated. Butterflyfishes form a high number of hybrids and represent an appropriate group to investigate hybridization in reef fishes. This study provides a rare test of terrestrially derived hybridization theory in the marine environment by examining hybridization between Chaetodon trifasciatus and C. lunulatus at Christmas Island. Overlapping spatial and dietary ecologies enable heterospecific encounters. Nonassortative mating and local rarity of both parent species appear to permit heterospecific breeding pair formation. Microsatellite loci and mtDNA confirmed the status of hybrids, which displayed the lowest genetic diversity in the sample and used a reduced suite of resources, suggesting decreased adaptability. Maternal contribution to hybridization was unidirectional, and no introgression was detected, suggesting limited, localized evolutionary consequences of hybridization.Comparisons to other reef fish hybridization studies revealed that different evolutionary consequences emerge, despite being promoted by similar factors, possibly due to the magnitude of genetic distance between hybridizing species. This study highlights the need for further enquiry aimed at evaluating the importance and long-term consequences of reef fish hybridization.  相似文献   
89.
In biomedical research, one key stage of translating basic science knowledge to clinical practice is the reconciliation of phenotypes employed for laboratory animal studies with those important for the clinical condition. Alcohol dependence (AD) is a prototypic complex genetic trait. There is a long history of behaviour-genetic studies of AD in both human subjects and various genetic animal models. This review assesses the state of the art in our understanding of the genetic contributions to AD. In particular, it primarily focuses on the phenotypes studied in mouse genetic animal models, comparing them to the aspects of the human condition they are intended to target. It identifies several features of AD where genetic animal models have been particularly useful, and tries to identify understudied areas where there is good promise for further genetic animal model work.  相似文献   
90.
根据自然灾害医学救援要求及组织体制,结合灾害救援过程中的心理压力来源及心理需求,提出心理卫生支援分队建设指导:人员需具备专业技能,兼顾全面技术;采取的工作方式主要为团体合作、小组协作和单人干预等;日常训练重点在于做好实战训练、预案、心理和物资方面的准备,力求使心理卫生支援分队满足新时期非战争军事任务的需要。  相似文献   
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