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101.
Epstein Leonard H.; Paluch Rocco A.; Gordy Constance C.; Saelens Brian E.; Ernst Michelle M. 《Canadian Metallurgical Quarterly》2000,68(4):717
This study randomized obese children from 67 families to groups that received a 6-month family-based behavioral weight-control program plus parent and child problem solving, child problem solving, or standard treatment with no additional problem solving. The standard group showed larger body mass index (BMI) decreases than the parent?+?child group through 2 years, with significant differences in the percentage of children who showed large BMI changes. Significant statistical and clinical improvements were observed over time in child behavior problems and parental distress. Parent problem solving increased in the parent?+?child condition relative to the other conditions, whereas child problem solving increased equally in all conditions. The bulk of evidence suggests that problem solving did not add to treatment effectiveness beyond the standard family-based treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Jeffery Constance J.; Koshland Daniel E. Jr 《Protein engineering, design & selection : PEDS》1999,12(10):863-872
The Escherichia coli aspartate receptor is a dimer with twotransmembrane sequences per monomer that connect a periplasmicligand binding domain to a cytoplasmic signaling domain. Themethod of 'hydrophobic-biased' random mutagenesis, that we describehere, was used to construct mutant aspartate receptors in whicheither the entire transmembrane sequence or seven residues nearthe center of the transmembrane sequence were replaced withhydrophobic and polar random residues. Some of these receptorsresponded to aspartate in an in vivo chemotaxis assay, whileothers did not. The acceptable substitutions included hydrophobicto polar residues, small to larger residues, and large to smallerresidues. However, one mutant receptor that had only a few hydrophobicsubstitutions did not respond to aspartate. These results addto our understanding of sequence specificity in the transmembraneregions of proteins with more than one transmembrane sequence.This work also demonstrates a method of constructing familiesof mutant proteins containing random residues with chosen characteristics. 相似文献
103.
Hildreth Ellen C.; Beusmans Jack M. H.; Boer Erwin R.; Royden Constance S. 《Canadian Metallurgical Quarterly》2000,26(3):1106
Experienced drivers performed simple steering maneuvers in the absence of continuous visual input. Experiments conducted in a driving simulator assessed drivers' performance of lane corrections during brief visual occlusion and examined the visual cues that guide steering. The dependence of steering behavior on heading, speed, and lateral position at the start of the maneuver was measured. Drivers adjusted steering amplitude with heading and performed the maneuver more rapidly at higher speeds. These dependencies were unaffected by a 1.5-s visual occlusion at the start of the maneuver. Longer occlusions resulted in severe performance degradation. Two steering control models were developed to account for these findings. In the 1st, steering actions were coupled to perceptual variables such as lateral position and heading. In the 2nd, drivers pursued a virtual target in the scene. Both models yielded behavior that closely matches that of human drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Day hospital and residential addiction treatment: Randomized and nonrandomized managed care clients.
Witbrodt Jane; Bond Jason; Kaskutas Lee Ann; Weisner Constance; Jaeger Gary; Pating David; Moore Charles 《Canadian Metallurgical Quarterly》2007,75(6):947
Male and female managed care clients randomized to day hospital (n=154) or community residential treatment (n=139) were compared on substance use outcomes at 6 and 12 months. To address possible bias in naturalistic studies, outcomes were also examined for clients who self-selected day hospital (n=321) and for clients excluded from randomization and directed to residential treatment because of high environmental risk (n=82). American Society of Addiction Medicine criteria defined study and randomization eligibility. More than 50% of followed clients reported past-30-day abstinence at follow-ups (unadjusted rates, not significant between groups). Despite differing baseline severities, randomized, self-selecting, and directed clients displayed similar abstinence outcomes in multivariate longitudinal models. Index treatment days and 12-step attendance were associated with abstinence (p 相似文献
105.
Constance Nozzolillo J. Thor Arnason Francisca Campos Natalie Donskov Marian Jurzysta 《Journal of chemical ecology》1997,23(4):995-1002
Dried alfalfa (Medicago sativa) leaf tissue incorporated in artificial diet to give a final concentration of 0.5 or 1.6 mg/g fresh weight of saponins significantly inhibited growth and development of larvae of the European corn borer (Ostrinia nubilalis). Saponin fractions isolated from root or shoot tissues of alfalfa also inhibited growth when incorporated at equivalent concentrations but had little effect on development. Root saponins were somewhat more harmful than shoot saponins. 相似文献
106.
Mamdouh M. Abou-Zaid Blair V. Helson Constance Nozzolillo J. Thor Arnason 《Journal of chemical ecology》2001,27(12):2517-2527
An ethanolic extract of red maple (Acer rubrum L.) leaves (RME) applied to trembling aspen (Populus tremuloides Michx.) leaves reduced feeding in choice test assays with forest tent caterpillar larvae (Malacosoma disstria Hbn.) (FTC), whereas a trembling aspen foliage extract, similarly applied, stimulated feeding. Compounds isolated from the RME were gallic acid, methyl gallate, ethyl gallate, m-digallate, ethyl m-digallate, 1-O-galloyl--D-glucose, 1-O-galloyl--L-rhamnose, kaempferol 3-O--D-glucoside, kaempferol 3-O--D-galactoside, kaempferol 3-O--L-rhamnoside, kaempferol-3-O-rhamnoglucoside, quercetin 3-O--D-glucoside, quercetin 3-O--L-rhamnoside and quercetin 3-O-rhamnoglucoside, (–)-epicatechin, (+)-catechin and ellagic acid. All of the gallates, (–)-epicatechin, and kaempferol 3-O--L-rhamnoside deterred feeding on trembling aspen leaf disks when applied at 0.28 mg/cm2. The two digallates deterred feeding by 90% and were the most effective. HPLC analysis indicated that ethyl m-digallate is present in amounts 10–100 × higher in RME (2.5–250 mg/g) than any other compound. Thus, ethyl m-digallate appears to be the major compound protecting red maple from feeding by FTC, with a minor contribution from other gallates. 相似文献
107.
108.
Haley William E.; Roth David L.; Coleton Marci I.; Ford Greg R.; West Constance A. C.; Colllins Robert P.; Isobe Teresa L. 《Canadian Metallurgical Quarterly》1996,64(1):121
Family caregivers of patients with Alzheimer's disease (AD) commonly have high levels of psychological distress. Black caregivers often report less depression than White caregivers, but the process underlying this difference is poorly understood. With the use of a stress process model, 123 White and 74 Black family caregivers of patients with AD and other progressive dementias were studied. Black caregivers appraised patient problems as less stressful and reported higher self-efficacy in managing caregiving problems and less depression than did White caregivers. White and Black caregivers also differed significantly in coping responses but not in social supports. Structural equation analyses indicated that the correlational structure of the stress process was similar in White and Black caregivers. Caregiving stressors and race did not affect well-being through direct paths, but they were mediated by effects for appraisal, social support and activity, and coping. Possible cultural mechanisms explaining the better adjustment among Black caregivers are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Mark T. Johnson Elke Kreft David D. N''Da Eberhard W. Neuse Constance E. J. van Rensburg 《Journal of Inorganic and Organometallic Polymers》2003,13(4):255-267
Water-soluble and biocompatible polymers containing bioreversibly attached ferrocene units as side chain terminals have in recent years attracted interest in drug research. In preliminary screens, polymers of this type have shown high antiproliferative activity against selected human carcinoma cell lines, paired with low in vivo toxicity. They may thus lend themselves as efficacious prodrugs in cancer chemotherapy. Cancers of the intestinal system are known to resist chemotherapeutic treatment. This general lack of sensitivity of the colorectal malignancies prompted us to investigate the in vitro behavior of selected carrier-bound ferrocene prodrugs against the Colo 320 DM cell line, a representative human adenocarcinoma of the colon. The findings of this investigation are reported in the present communication. The carriers 1 to 10 used for conjugation with the metallocene are water-soluble aliphatic polyamides featuring primary or secondary amine functionality as side chain terminals or main chain constituents. By previously developed methodology these amino groups are coupled with the ferrocenylation agent, 4-ferrocenylbutanoic acid, generating the target conjugates 1-Fc to 10-Fc, in which the metallocene is bound through amide or hydrazone links. Cell culture tests are performed by established protocol against the Colo line and, for comparison, also against the HeLa cells. Significantly, while outstanding performance is observed for most of the conjugates against both cell lines, the results indicate activities in the Colo screens to be higher on average than determined in the sensitive HeLa tests. 相似文献
110.
The purpose of this research was to develop an objective, linear measure of mothers' confidence to care for children assisted with tracheostomy medical technology in their homes. Caregiver confidence is addressed in this research for three technologies, namely, a) trachesotomy, b) tracheostomy and ventilator, and c) BiPAP/CPAP although detailed measurement results are only reported for tracheostomy, and its co-calibration with tracheostomy and ventilator caregiving items. The sample consisted of 53 mothers responding to several caregiver questionnaires based on a caregiving task matrix after content and clinical validation. A major challenge was integrating this construct with overarching principles already established by Functional Caregiving, a multi-level humanistic caregiving model for children with intellectual disabilities. Empirical analyses included principal components analysis, and then linear transformation of Tracheostomy item ratings to an objective, equal-interval scale with a Rasch model. Results show caregiver separation on the Tracheostomy caregiving scale was 2.66 and reliability, .88. In general, co-calibration improved measurement properties without affecting mothers' caregiving confidence measures. Although sample size was small, measuring mothers' confidence to care for a child supported by complex medical technologies appears very promising. 相似文献