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961.
Prior research indicates that physical health and social support have substantial influences on subjective well-being among older adults. However, little research has examined the influences of coping style and cognitive functioning on subjective well-being among older adults. This study investigated cognitive and psychosocial predictors of subjective well-being among 129 adults, ages 65-89 years. Canonical correlation indicated that subjective well-being was characterized by two dimensions: life satisfaction and affective balance (happiness). The use of emotion-focused coping strategies and poor perceived health were associated with diminished perceptions of life satisfaction, whereas task-oriented and avoidance-oriented coping were positively related to happiness. Cognitive functioning was positively related to life satisfaction and pleasant emotions independent of education and income.  相似文献   
962.

Background

Surges in heart rate (HR) and blood pressure (BP) at apnea termination contribute to the hypertension seen in obstructive sleep apnea (OSA). Because childhood OSA prevalence peaks in the preschool years, we aimed to characterize the cardiovascular response to obstructive events in preschool-aged children.

Methods

Clinically referred children aged 3–5 years were grouped by obstructive apnea–hypopnea index (OAHI) into the following: primary snoring (PS) (OAHI ? 1 event/h [n = 21]), mild OSA (OAHI > 1– ? 5 [n = 32]), and moderate to severe (MS) OSA (OAHI > 5 [n = 28]). Beat-to-beat pulse transit time (PTT), an inverse continuous indicator of BP changes, and HR were averaged during the two halves (early and late) and during the peak after (post) each obstructive event and were expressed as percentage change from late- to post-event.

Results

We analyzed 422 events consisting of 55 apneas and 367 hypopneas. A significant post-event increase in HR and fall in PTT occurred in all severity groups (P < .05 for all). A greater response was associated with OSA, nonrapid eye movement sleep (NREM), cortical arousal, hypopneas, and oxygen desaturation (P < .05 for all).

Conclusions

Obstructive events elicit acute cardiovascular changes in preschool children. Such circulatory perturbations have been implicated in the development of hypertension, and our findings complement previous studies to suggest a cumulative impact of snoring on the cardiovascular system from childhood into adulthood.  相似文献   
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Depressive mood in adolescents with bipolar disorder (BDd) is associated with significant morbidity and mortality, but we have limited information about neural correlates of depression and treatment response in BDd. Ten adolescents with BDd (8 females, mean age = 15.6?±?0.9) completed two (fearful and happy) face gender labeling fMRI experiments at baseline and after 6-weeks of open treatment. Whole-brain analysis was used at baseline to compare their neural activity with those of 10 age and sex-matched healthy controls (HC). For comparisons of the neural activity at baseline and after treatment of youth with BDd, region of interest analysis for dorsal/ventral prefrontal, anterior cingulate, and amygdala activity, and significant regions identified by wholebrain analysis between BDd and HC were analyzed. There was significant improvement in depression scores (mean percentage change on the Child Depression Rating Scale-Revised 57 %?±?28). Neural activity after treatment was decreased in left occipital cortex in the intense fearful experiment, but increased in left insula, left cerebellum, and right ventrolateral prefrontal cortex in the intense happy experiment. Greater improvement in depression was associated with baseline higher activity in ventral ACC to mild happy faces. Study sample size was relatively small for subgroup analysis and consisted of mainly female adolescents that were predominantly on psychotropic medications during scanning. Our results of reduced negative emotion processing versus increased positive emotion processing after treatment of depression (improvement of cognitive bias to negative and away from positive) are consistent with the improvement of depression according to Beck’s cognitive theory.  相似文献   
967.
微核(micronuclei,MN),也叫卫星核,是真核生物细胞中的一种异常结构,是基因组不稳定在细胞中的一种表现形式,根据其内容物成分来源分为“染色体型微核”和染色体外元件形成的微核,即“双微体型微核”,这两种形式微核在同一细胞中是独立产生和存在的.双微体是在肿瘤细胞中常见的染色体外元件,因此,了解双微体型微核产生的分子机制将有助于更清楚这些染色体外结构是如何保留在细胞内或者排出细胞外的.该文就双微体型微核产生的分子机制及微核的生物学活性作一综述.  相似文献   
968.
Female sex workers (FSWs) continue to represent a high-risk population in need of targeted HIV prevention interventions. Targeting environmental risk factors should result in more sustainable behavior change than individual-level interventions alone. There are many types of FSWs who operate in and through a variety of micro- (eg, brothels) and macro-level (eg, being sex-trafficked) contexts. Efforts to characterize FSWs and inform HIV prevention programs have often relied on sex work typologies or categorizations of FSWs by venue or type. We conducted a systematic search and qualitatively reviewed 37 published studies on venue-based FSWs to examine the appropriateness of sex work typologies, and the extent to which this research has systematically examined characteristics of different risk environments. We extracted information on study characteristics like venue comparisons, HIV/STI prevalence, and sampling strategies. We found mixed results with regards to the reliability of typologies in predicting HIV/STI infection; relying solely on categorization of FSWs by venue or type did not predict seroprevalence in a consistent manner. Only 65 % of the studies that allowed for venue comparisons on HIV/STI prevalence provided data on venue characteristics. The factors that were assessed were largely individual-level FSW factors (eg, demographics, number of clients per day), rather than social and structural characteristics of the risk environment. We outline a strategy for future research on venue-based FSWs that ultimately aims to inform structural-level HIV interventions for FSWs.  相似文献   
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Antimicrobials administered postexposure can reduce the incidence or progression of anthrax disease, but they do not protect against the disease resulting from the germination of spores that may remain in the body after cessation of the antimicrobial regimen. Such additional protection may be achieved by postexposure vaccination; however, no anthrax vaccine is licensed for postexposure prophylaxis (PEP). In a rabbit PEP study, animals were subjected to lethal challenge with aerosolized Bacillus anthracis spores and then were treated with levofloxacin with or without concomitant intramuscular (i.m.) vaccination with anthrax vaccine adsorbed (AVA) (BioThrax; Emergent BioDefense Operations Lansing LLC, Lansing, MI), administered twice, 1 week apart. A significant increase in survival rates was observed among vaccinated animals compared to those treated with antibiotic alone. In preexposure prophylaxis studies in rabbits and nonhuman primates (NHPs), animals received two i.m. vaccinations 1 month apart and were challenged with aerosolized anthrax spores at day 70. Prechallenge toxin-neutralizing antibody (TNA) titers correlated with animal survival postchallenge and provided the means for deriving an antibody titer associated with a specific probability of survival in animals. In a clinical immunogenicity study, 82% of the subjects met or exceeded the prechallenge TNA value that was associated with a 70% probability of survival in rabbits and 88% probability of survival in NHPs, which was estimated based on the results of animal preexposure prophylaxis studies. The animal data provide initial information on protective antibody levels for anthrax, as well as support previous findings regarding the ability of AVA to provide added protection to B. anthracis-infected animals compared to antimicrobial treatment alone.  相似文献   
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