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111.
Knowledge of child rearing and child development is relevant to parenting and the well-being of children. Using a sociodemographically heterogeneous sample of 268 European American mothers of 2-year-olds, we assessed the state of mothers' parenting knowledge; compared parenting knowledge in groups of mothers who varied in terms of parenthood and social status; and identified principal sources of mothers' parenting knowledge in terms of social factors, parenting supports, and formal classes. On the whole, European American mothers demonstrated fair but less than complete basic parenting knowledge; age, education, and rated helpfulness of written materials each uniquely contributed to mothers' knowledge. Adult mothers scored higher than adolescent mothers, and mothers improved in their knowledge of parenting from their first to their second child (and were stable across time). No differences were found between mothers of girls and boys, mothers who varied in employment status, or birth and adoptive mothers. The implications of variation in parenting knowledge and its sources for parenting education and clinical interactions with parents are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
112.
113.
PURPOSE: This multicenter phase II study was designed to assess the efficacy of the alternating schedule of irinotecan (CPT-11) with bolus 5-fluorouracil (5-FU) and leucovorin (LV) in first-line chemotherapy for metastatic colorectal cancer (CRC). PATIENTS AND METHODS: Patients with histologically proven metastatic colorectal cancer, and at least one bidimensionally measurable lesion, aged 18-70, with performance status < or = 2, normal baseline biological values and no prior chemotherapy (or only adjuvant chemotherapy completed > or = 6 months before study entry) were selected. Treatment was irinotecan 350 mg/m2, i.v., day 1, alternating with leucovorin 20 mg/m2 i.v. and 5-FU 425 mg/m2, i.v. daily for five consecutive days, day 22-26 (Mayo Clinic regimen). One alternating cycle was to be performed every six weeks. Patients were evaluated for efficacy every alternating cycle. Treatment was administered until five alternating cycles, disease progression, unacceptable toxicity or patient refusal. RESULTS: Thirty-three patients (28 chemotherapy-na?ve and five with prior adjuvant treatment completed > 1 year prior to accrual) were enrolled. The objective response rate (RR) was 30% (95% CI: 16-49; 10 patients/33; nine partial response and one complete response). All responses were reviewed by an independent external review committee. An additional 49% of patients had stable disease. The median survival was 16 months, the one year survival amounted to 58% and the median progression free survival was 7.2 months. Relative dose intensity was nearly 90% for both drugs. Grade 3-4 diarrhea and neutropenia were the most frequent severe toxic events, seen in 24% and 64% of patients, respectively. CONCLUSIONS: The alternating schedule of CPT-11 350 mg/m2 with five days bolus of 5-FU and low dose LV is an active and feasible regimen as front-line therapy for metastatic CRC. It is well tolerated, without evidence of overlapping toxicity. The response rate appears promising with regard to that expected with either single agent. This regimen warrants further assessment in randomized trials.  相似文献   
114.
Changes in the intrinsic structure of paint surfaces resulting from extended UV exposure can significantly alter the appearance of paint due to a breakdown in the resin that binds the pigments and flattening agents. In this study, the coating structure of a solvent-based poly-urethane was analyzed to establish correlations between the intrinsic spatial scaling properties of the coating and UV exposure time. Atomic force microscopy and laser scanning confocal microscopy were employed to map surface structures over a range of scales from 80 nm to 80 εm. The roughness of the polyurethane surface was characterized in terms of scaling exponents using detrended fluctuation analysis to identify long-range, power law relations, and to correct for inhomogeneities in the surface structure. The time-dependence of the roughening process was also determined and correlated with changes in gloss. AMSTA-AR-CCB-TA, Watervliet, NY 12189-4050. Email: majohn@pica.army.mil and pcote@pica.army.mil  相似文献   
115.
The crystal structure of the mouse major histocompatibility complex (MHC) class I molecule H-2Dd with an immunodominant peptide, designated P18-I10 (RGPGRAFVTI), from human immunodeficiency virus envelope glycoprotein 120 was determined at 3.2 A resolution. A novel orientation of the alpha3 domain of Dd relative to the alpha1/alpha2 domains results in significantly fewer contacts between alpha3 and beta2-microglobulin compared with other MHC class I proteins. Four out of ten peptide residues (P2 Gly, P3 Pro, P5 Arg and P10 Ile) are nearly completely buried in the Dd binding groove. This is consistent with previous findings that Dd exploits a four-residue binding motif comprising a glycine at P2, a proline at P3, a positively charged residue at P5, and a C-terminal hydrophobic residue at P9 or P10. The side-chain of P5 Arg is directed toward the floor of the predominantly hydrophobic binding groove where it forms two salt bridges and one hydrogen bond with Dd residue Asp77. The selection of glycine at P2 appears to be due to a narrowing of the B pocket, relative to that of other class I molecules, caused by Arg66 whose side-chain folds down into the binding cleft. Residue P3 Pro of P18-I10 occupies part of pocket D, which in Dd is partially split by a prominent hydrophobic ridge in the floor of the binding groove formed by Trp97 and Trp114. Residues P6 through P9 form a solvent-exposed bulge, with P7 Phe protruding the most from the binding groove and thereby probably constituting a major site of interaction with T cell receptors. A comparison of H-2Dd/P18-I10 with other MHC class I/peptide complexes of known structure provides insights into the possible basis for the specificity of the natural killer cell receptor Ly-49A for several related class I molecules.  相似文献   
116.
LPS and selected cytokines upregulate xanthine dehydrogenase/xanthine oxidase (XDH/XO) in cellular systems. However, the effect of these factors on in vivo XDH/XO expression, and their contribution to lung injury, are poorly understood. Rats were exposed to normoxia or hypoxia for 24 h after treatment with LPS (1 mg/kg) and IL-1beta (100 microg/kg) or sterile saline. Lungs were then harvested for measurement of XDH/XO enzymatic activity and gene expression, and pulmonary edema was assessed by measurement of the wet/dry lung weight ratio (W/D). Although treatment with LPS + IL-1beta or hypoxia independently produced a 2-fold elevation (p < 0. 05 versus exposure to normoxia and treatment with saline) in lung XDH/XO activity and mRNA, the combination of LPS + IL-1beta and hypoxia caused a 4- and 3.5-fold increase in these values, respectively. XDH/XO protein expression was increased 2-fold by hypoxia alone and 1.3-fold by treatment with LPS + IL-1beta alone or combination treatment. Compared with normoxic lungs, W/D was significantly increased by exposure to hypoxia, LPS + IL-1beta, or combination treatment. This increase was prevented by treatment of the animals with tungsten, which abrogated lung XDH/XO activity. In conclusion, LPS, IL-1beta, and hypoxia significantly upregulate lung XDH/XO expression in vivo. The present data support a role for this enzyme in the pathogenesis of acute lung injury.  相似文献   
117.
Objective: To examine the relation of illness intrusiveness and illness uncertainty to psychological distress in patients with multiple sclerosis (MS). Study Design: Participants were recruited from regional support groups and local neurologists. Participants completed self-report measures of illness intrusiveness, illness uncertainty, and psychological distress. Disease status was assessed by administration of a mental status exam and an index of ambulation. Participants: The sample included 78 (55 women, 23 men) individuals diagnosed with MS. Main Outcome Measure: The Symptom Checklist—90—Revised Global Severity Index. Results: Hierarchical regression analyses indicated that illness intrusiveness and illness uncertainty independently predicted adjustment problems above and beyond demographic and illness variables. No mediator or moderator relationships were found for illness intrusiveness. Conclusions: Psychological appraisals of illness are salient predictors of adjustment even after statistically controlling for the influence of age, education, and objective indices of physical and cognitive impairment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
118.
We present a semi-fixed-length motion vector coding method for H.263-based low bit rate video compression. The method exploits structural constraints within the motion field. The motion vectors are encoded using semi-fixed-length codes, yielding essentially the same levels of rate-distortion performance and subjective quality achieved by H.263's Huffman-based variable length codes in a noiseless environment. However, such codes provide substantially higher error resilience in a noisy environment.  相似文献   
119.
Basé sur des concepts de transferts simultanés de masse et d'énergie, un modèle différentiel est posé pour le séchage en continu des couches minces par rayonnement infrarouge. Des essais conduits sur le séchage d'une nappe de coton non-mercerisé dans un séchoir semi-industriel d'une capacité maximale de 20 kW ont servi à la calibration du modèle. Les simulations, par intégration numérique des bilans de masse et d'énergie, fournissent les conditions à la sortie du séchoir: température de l'air, température du tissu et degré d'humidité résiduelle dans la nappe. Une étude de sensibilité indique que la température des émetteurs infrarouges est le paramètre qui influence le plus significativement le séchage. Les résultats montrent également que l'air alimenté sert presqu'uniquement à évacuer la vapeur produite, le transfert de chaleur par convection étant faible par rapport au rayonnement.  相似文献   
120.
The number of sleep spindles remains relatively stable within individuals from night to night. However, there is little explanation for the large interindividual differences in spindles. The authors investigated the relationship between spindles and intelligence quotient (IQ) in 3 separate studies. The number of spindles and sigma power were positively correlated with performance IQ (PIQ), but not verbal IQ (VIQ). The perceptual/analytical skills measured by the PIQ Picture Completion subscale accounted for most of the interindividual differences in spindles. Furthermore, there was a relationship between the rapid eye movements (REMs) of REM sleep and VIQ in individuals with higher IQ scores. A similar pattern was observed between spindles and PIQ. It was hypothesized that high-IQ individuals have more spindles that can support more complex cortical networks underlying perceptual/analytical abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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