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101.
102.
Longitudinal relations between child vagal tone and parenting behavior: 2 to 4 years 总被引:3,自引:0,他引:3
The longitudinal relations between physiological markers of child emotion regulation and maternal parenting practices were examined from 2 to 4 years of age. At Time 1, cardiac vagal tone was assessed for one hundred four 2-year-olds (54 females); their mothers completed an assessment of parenting styles. Two years later, at Time 2, 84 of the original participants were reassessed on measures of cardiac vagal tone and parenting style. Results indicated both baseline cardiac vagal tone and maternal parenting practices to be stable from 2 to 4 years of age. Children's cardiac vagal tone predicted specific parenting practices from the toddler to preschool years. Further, child cardiac vagal tone moderated maternal restrictive-parenting practices from 2 to 4 years of age; mothers of children who were highly or moderately physiologically dysregulated were more likely to report restrictive parenting practices at both 2 and 4 years of age. 相似文献
103.
Hastings RH 《Respiratory physiology & neurobiology》2004,142(2-3):95-113
Parathyroid hormone-related protein (PTHrP) is expressed in normal and malignant lung and has roles in development, homeostasis, and pathophysiology of injury and cancer. Its effects in developing lung include regulation of branching morphogenesis and type II cell maturation. In adult lung, PTHrP stimulates disaturated phosphatidylcholine secretion, inhibits type II cell growth, and sensitizes them to apoptosis. In lung cancer, PTHrP may play a role in carcinoma progression, or metastasis. The protein could be a useful marker for assessing lung maturity or type II cell function, predicting risk of injury, and detecting lung cancer. PTHrP-based therapies could also prove useful in lung injury and lung cancer. 相似文献
104.
105.
Existing research on support staff has been focused on variables associated with stress. However, there has been little attention to the possibility that staff may also experience a number of positive outcomes or perceptions. In the present study, 101 support staff working with adults who had mental retardation completed measures of burnout and mental health and a new measure: the Staff Positive Contributions Questionnaire (SPCQ). A range of positive perceptions of their work was endorsed by participants, demonstrating that such perceptions do exist and require theoretical explanation. The SPCQ had promising internal consistency, test-retest reliability, and construct validity. Thus, further research with this instrument is warranted. 相似文献
106.
Previous studies have demonstrated methamphetamine (METH)-induced toxicity to dopaminergic and serotonergic axons in rat striatum. Although several studies have identified the nature of reactive astrogliosis in this lesion model, the response of microglia has not been examined in detail. In this investigation, we characterized the temporal relationship of reactive microgliosis to neuropathological alterations of dopaminergic axons in striatum following exposure to methamphetamine. Adult male Sprague-Dawley rats were administered a neurotoxic regimen of methamphetamine and survived 12 h, or 1, 2, 4, and 6 days after treatment. Immunohistochemical methods were used to evaluate reactive changes in microglia throughout the brain of methamphetamine-treated rats, with a particular focus upon striatum. Pronounced morphological changes, indicative of reactive microgliosis, were evident in the brains of all methamphetamine-treated animals and were absent in saline-treated control animals. These included hyperplastic changes in cell morphology that substantially increased the size and staining intensity of reactive microglia. Quantitative analysis of reactive microglial changes in striatum demonstrated that these changes were most robust within the ventrolateral region and were maximal 2 days after methamphetamine administration. Analysis of tissue also revealed that microglial activation preceded the appearance of pathological changes in striatal dopamine fibers. Reactive microgliosis was also observed in extra-striatal regions (somatosensory and piriform cortices, and periaqueductal gray). These data demonstrate a consistent, robust, and selective activation of microglia in response to methamphetamine administration that, at least in striatum, precedes the appearance of morphological indicators of axon pathology. These observations raise the possibility that activated microglia may contribute to methamphetamine-induced neurotoxicity. 相似文献
107.
Salivary testosterone diurnal variation and psychopathology in adolescent males and females: individual differences and developmental effects 总被引:4,自引:0,他引:4
Granger DA Shirtcliff EA Zahn-Waxler C Usher B Klimes-Dougan B Hastings P 《Development and psychopathology》2003,15(2):431-449
Individual differences in salivary testosterone were examined in 213 adolescents (106 boys, 107 girls; mean age = 13.66 years) in relation to externalizing and internalizing psychopathology. Self- and parent-report measures of behavior problems and psychiatric symptoms were obtained. Latent anxiety-depression, disruptive behavior, and attention problem constructs were developed using multitrait, multimethod procedures. Saliva samples were collected in the morning, midday, and late afternoon on multiple days and were later assayed for testosterone. Latent constructs were derived for testosterone level and diurnal variation across the six sampling occasions. Structural equations modeled relationships between problem behavior and intra- and interindividual differences in testosterone separately by gender. For boys, lower levels of testosterone and testosterone levels that decreased more slowly across the day were related to higher levels of anxiety-depression and attention problems. These associations were not moderated by pubertal development. For girls, steep declines in testosterone production across the day related to higher levels of disruptive behavior problems, but this association was only evident after including pubertal development as a moderator in the model. These findings raise novel questions regarding the nature and magnitude of links between testosterone and problem behavior in youth. 相似文献
108.
Ten years ago research showed that pro-smoking images were prevalent in British youth magazines, whereas there was little coverage of smoking and health. Since then there has been a great expansion in the number of youth magazines, and particularly those aimed at young men. Titles such as FHM and Loaded, which did not exist at the time of the previous research, are now market leaders. New qualitative and quantitative research has therefore been conducted to examine the prevalence and impact of smoking images in this revitalised youth style magazines market. This paper presents the findings of the qualitative element of this research, which examined British first year students' perceptions of the pro-smoking imagery found in the magazines and explored the relationship between this and their own smoking images and identities. The research found that: (a) this imagery was perceived to be, on the whole, attractive, sociable and reassuring; (b) that it supported young people's perceptions of smoking and reinforced their smoker identities; and (c) that it has the potential to be more powerful than advertising imagery. 相似文献
109.
Klimes-Dougan B Hastings PD Granger DA Usher BA Zahn-Waxler C 《Development and psychopathology》2001,13(3):695-719
The purpose of this study was to examine adrenocortical activity (basal, diurnal variation, and responses to social stressors) in adolescents at risk for psychopathology. Salivary cortisol levels were examined in normally developing and at-risk youth with internalizing and externalizing symptoms ranging from subclinical to clinical levels. Adolescents showed expected patterns of diurnal variation, with high early morning cortisol levels and a pattern of decline throughout the day. Females showed higher midday and late afternoon levels than males, and these patterns interacted with risk status. Internalizing problems sometimes were associated with gradual rather than steep declines in basal cortisol production. Both immediate and delayed cortisol reactivity to a social performance stressor were associated with internalizing symptoms. There was no evidence of relations between externalizing problems and underarousal of the hypothalamic-pituitary-adrenal (HPA) system. These and other results suggest that gender is an important moderating factor linking psychopathology. development, and context with HPA axis functioning in adolescence. 相似文献
110.
mRNA 5'-leader trans-splicing in the chordates 总被引:2,自引:0,他引:2
We report the discovery of mRNA 5'-leader trans-splicing (SL trans-splicing) in the chordates. In the ascidian protochordate Ciona intestinalis, the mRNAs of at least seven genes undergo trans-splicing of a 16-nucleotide 5'-leader apparently derived from a 46-nucleotide RNA that shares features with previously characterized splice donor SL RNAs. SL trans-splicing was known previously to occur in several protist and metazoan phyla, however, this is the first report of SL trans-splicing within the deuterostome division of the metazoa. SL trans-splicing is not known to occur in the vertebrates. However, because ascidians are primitive chordates related to vertebrate ancestors, our findings raise the possibility of ancestral SL trans-splicing in the vertebrate lineage. 相似文献