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1.
The authors used a longitudinal, prospective design to investigate a moderation effect in the association between a genetic vulnerability factor, a variable nucleotide repeat polymorphism in the promoter region of 5HTT (5-HTTLPR), and increases in youths' substance use. The primary study hypothesis predicted that involved-supportive parenting would attenuate the link between the 5-HTTLPR polymorphism and longitudinal increases in substance use. African American youths residing in rural Georgia (N = 253, mean age = 11.5 years) provided 4 waves of data on their own substance use; the mothers of the youths provided data on their own parenting practices. Genetic data were obtained from youths via saliva samples. Latent growth curve modeling indicated that 5-HTTLPR status (presence of 1 or 2 copies of the s allele) was linked with increases in substance use over time; however, this association was greatly reduced when youths received high levels of involved-supportive parenting. This study demonstrates that parenting processes have the potential to ameliorate genetic risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The rising economic cost of floods in the United States cannot be explained solely by monetary inflation or growth in coastal populations. Damaging flood events are also influenced by the way society plans for and physically develops its communities, influencing where structures and impervious surfaces are concentrated and how hydrological systems are altered. We analyze 383 nonhurricane flood events in Florida counties between 1997 and 2001 to isolate how planning decisions and their effects on the built environment affect property damage caused by floods. Our results suggest that alteration of naturally occurring wetlands significantly increases the property damage caused by floods, all else equal. Also, nonstructural methods such as the Federal Emergency Management Agency's Community Rating System, while providing inexpensive means of reducing property damage directly, may also indirectly encourage more development in hazardous areas.  相似文献   
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The entailment model of attributions is examined for the first time using a dyadic approach and longitudinal data. In a sample of 229 married partners with children, causal attributions were distinguished empirically from responsibility attributions and, consistent with the entailment model, the effect of causal attributions on conflict was mediated through attributions of responsibility. Only 1 path was influenced by spouse gender. Examination of cross-spouse effects revealed significant effects and provided a better fit than a model with no cross-spouse effects. The importance of including cross-spouse effects in attributional models is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The effects of the pubertal transition on behavior problems and its interaction with family and neighborhood circumstances were examined with a sample of 867 African American children 10-12 years of age. Pubertal development status, pubertal timing, and primary caregivers' parenting behaviors were significantly related to affiliation with deviant peers and externalizing behaviors. Externalizing behavior among early-maturing children was associated positively with primary caregivers' use of harsh-inconsistent discipline and negatively with nurturant-involved parenting practices. Disadvantaged neighborhood conditions were significantly associated with deviant peer affiliation. The effect of pubertal transition varied according to family and neighborhood conditions: Early-maturing children living in disadvantaged neighborhoods were significantly more likely to affiliate with deviant peers. Early-maturing children with harsh and inconsistent parents were significantly more likely to have externalizing problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Theoretical Analysis of the CW Doppler Ultrasonic Flowmeter   总被引:5,自引:0,他引:5  
The widespread application of ultrasonic techniques for the measurement of pulsatile blood flow has been hampered by the lack of a detailed theoretical understanding of the Doppler ultrasonic flowmeter. A general model for the Doppler flowmeter based upon stochastic considerations of the scattering of ultrasound by blood is introduced in this paper. The model characterizes the back- scattered ultrasound as a Gaussian random process and the expression for the autocovariance function is derived. For the CW Doppler flowmeter, the power spectral density function is computed, and its significance is emphasized: measurement of blood flow velocity corresponds to estimation of the average frequency of the Doppler power spectrum.  相似文献   
8.
Estradiol-17beta (E2) acts through the estrogen receptor (ER) to regulate uterine growth and functional differentiation. To determine whether E2 elicits epithelial mitogenesis through epithelial ER versus indirectly via ER-positive stromal cells, uteri from adult ER-deficient ER knockout (ko) mice and neonatal ER-positive wild-type (wt) BALB/c mice were used to produce the following tissue recombinants containing ER in epithelium (E) and/or stroma (S), or lacking ER altogether: wt-S + wt-E, wt-S + ko-E, ko-S + ko-E, and ko-S + wt-E. Tissue recombinants were grown for 4 weeks as subrenal capsule grafts in intact female nude mice, then the hosts were treated with either E2 or oil a week after ovariectomy. Epithelial labeling index and ER expression were determined by [3H]thymidine autoradiography and immunohistochemistry, respectively. In tissue recombinants containing wt-S (wt-S + wt-E, wt-S + ko-E), E2 induced a similar large increase in epithelial labeling index compared with oil-treated controls in both types of tissue recombinants despite the absence of epithelial ER in wt-S + ko-E tissue recombinants. This proliferative effect was blocked by an ER antagonist, indicating it was mediated through ER. In contrast, in tissue recombinants prepared with ko-S (ko-S + ko-E and ko-S + wt-E), epithelial labeling index was low and not stimulated by E2 despite epithelial ER expression in ko-S + wt-E grafts. In conclusion, these data demonstrate that epithelial ER is neither necessary nor sufficient for E2-induced uterine epithelial proliferation. Instead, E2 induction of epithelial proliferation appears to be a paracrine event mediated by ER-positive stroma. These data in the uterus and similar studies in the prostate suggest that epithelial mitogenesis in both estrogen and androgen target organs are stromally mediated events.  相似文献   
9.
The psychiatric comorbidity, health, and functioning of primary care patients with alcohol abuse and dependence (AAD) was investigated in a sample of 1,000 patients. Psychiatric symptomatology was assessed with the Primary Care Evaluation of Mental Disorders (PRIME-MD) diagnostic system. Health and functional status was assessed with the Medical Outcomes Study Short Form General Health Survey (SF-20). Results indicated that use of the PRIME-MD system brought about a 71% increase in physician recognition of AAD. AAD patients were diagnosed with substantial psychiatric comorbidity, and they reported poorer health and functioning than did patients without any psychiatric disorders. However, they reported less impairment and psychiatric comorbidity than did patients with other psychiatric disorders. Results also indicated that AAD patients' health and functioning were associated with the presence or absence of psychiatric comorbidity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Recombinant human adenovirus (Ad) vectors are leading candidates for human gene therapy for cystic fibrosis (CF) based on demonstration of efficient transfer of exogenous genes to rodent respiratory epithelium in vivo and human respiratory cells in vitro. The safety of Ad-mediated gene transfer to the respiratory epithelium and acute (up to 21 days) clinical responses to airway delivery of a replication-deficient recombinant, E1-, E3- Ad type 5-based vector containing the human cystic fibrosis transmembrane conductance regulator cDNA (AdCFTR) were evaluated in rhesus monkeys. Airway delivery of an Ad vector with the lacZ marker gene demonstrated beta-galactosidase expression in epithelial cells. Animals administered intratracheal AdCFTR demonstrated human CFTR cDNA expression in airway epithelial cells. Animals administered AdCFTR intranasal, and 24 hr later, intrabronchial [2 x 10(7) to 5 x 10(10) plaque-forming units (pfu), n = 12], in a fashion similar to a proposed human protocol, or only intrabronchial (10(11) pfu, n = 3), had no significant changes in clinical parameters compared to vehicle controls (n = 6). Microscopic analysis of the lung by necropsy or bronchoalveolar lavage demonstrated a dose-dependent increase in inflammatory cells, primarily lymphocytes, in the area where AdCFTR was delivered, which persisted for at least 2 months in some animals. Serum anti-Ad type 5 neutralizing antibody titers did not rise and shed Ad was not detected. The presence of AdCFTR DNA, analyzed by the polymerase chain reaction (PCR), was not detected in organs outside the lung. These data demonstrate that AdCFTR is well tolerated in non-human primates, although there is dose-dependent inflammation in the lung not clinically apparent.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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