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Taft Casey T.; Watkins Laura E.; Stafford Jane; Street Amy E.; Monson Candice M. 《Canadian Metallurgical Quarterly》2011,79(1):22
Objective: The authors conducted a meta-analysis of empirical studies investigating associations between indices of posttraumatic stress disorder (PTSD) and intimate relationship problems to empirically synthesize this literature. Method: A literature search using PsycINFO, Medline, Published International Literature on Traumatic Stress (PILOTS), and Dissertation Abstracts was performed. The authors identified 31 studies meeting inclusion criteria. Results: True score correlations (ρ) revealed medium-sized associations between PTSD and intimate relationship discord (ρ = .38, N = 7,973, K = 21), intimate relationship physical aggression perpetration (ρ = .42, N = 4,630, K = 19), and intimate relationship psychological aggression perpetration (ρ = .36, N = 1,501, K = 10). The strength of the association between PTSD and relationship discord was higher in military (vs. civilian) samples, and when the study was conducted in the United States (vs. other country), and the study represented a doctoral dissertation (vs. published article). The strength of the association between PTSD and physical aggression was higher in military (vs. civilian) samples, males (vs. females), community (vs. clinical) samples, studies examining PTSD symptom severity (vs. diagnosis), when the physical aggression measure focused exclusively on severe violence (vs. a more inclusive measure), and the study was published (vs. dissertation). For the PTSD–psychological aggression association, 98% of the variance was accounted for by methodological artifacts such as sampling and measurement error; consequently, no moderators were examined in this relationship. Conclusions: Findings highlight a need for the examination of models explaining the relationship difficulties associated with PTSD symptomatology and interventions designed to treat problems in both areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Many applied thermodynamic models are based on the local composition concept, that is, that the composition of neighboring molecules around a central molecule is different from the bulk fluid composition. In this paper we consider the rigorous calculation of local compositions for a model mixture of squarewell molecules via statistical mechanics using Monte Carlo simulations and integral equation theory. The results show that the currently available models do not correctly describe the density and composition dependence of the local structure.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A. 相似文献
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FC Schr?der JJ Farmer AB Attygalle SR Smedley T Eisner J Meinwald 《Canadian Metallurgical Quarterly》1998,281(5375):428-431
The pupal defensive secretion of the coccinellid beetle Epilachna borealis is composed principally of a combinatorial library of macrocyclic polyamines. These compounds constitute a previously unrecognized family of natural products, characterized by extremely large-ring lactonic structures derived from a small set of (2-hydroxyethylamino)alkanoic acids. The combinatorial assembly of these simple building blocks generates a high degree of structural diversity, which is further increased by slow, spontaneous intramolecular rearrangement of the macrocycles. 相似文献
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BACKGROUND: Subvalvular preservation is necessary to maintain left ventricular function, but accidental retention of infected tissue could cause postoperative endocarditis. METHODS: We examined 71 consecutive patients who underwent operation for mitral endocarditis. Endocarditis was uncontrolled and active in 24 patients, partially treated (unfinished antibiotic course) in 17, and healed in 30. RESULTS: Valves were repaired in 17% versus 59% versus 63% and replaced with subvalvular preservation in 25% versus 6% versus 3% of the uncontrolled active, partially treated, and healed groups, respectively. Thirty-day mortality was 29% versus 0% versus 3.3% (p=0.003), total mortality was 46% versus 18% versus 17% (p=0.035), and complications-related mortality was 38% versus 11% versus 13% (p=0.054), respectively. There was a trend toward lower complications-related mortality with subvalvular preservation than without. Postoperative endocarditis occurred in 3 of 30 patients without and 1 of 41 patients with subvalvular preservation. CONCLUSIONS: Postoperative mortality in uncontrolled active mitral endocarditis remains high, but results are good with partially treated or healed endocarditis. Subvalvular preservation improves outcome, does not increase postoperative endocarditis rates, and should be performed whenever feasible. 相似文献
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Radiolabeling permits the detection of trace amounts of zwitterionic detergent remaining in extracted hydrophobic or membrane proteins. To develop a sensitive and specific assay for its presence, the commonly used zwitterionic membrane protein detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (Chaps) was synthesized in a tritiated form. Synthesis via 7-ketodeoxycholic acid gave [7-3H]Chaps in 53% yield with a specific activity of 0.85 mCi/mmol. A novel solvent extraction system for cholic acid obviated the need for chromatographic isolation of this intermediate. The protocol can be readily modified to yield [7-3H]Chaps of higher specific activity. [7-3H]Chaps was used to monitor the efficiency of various strategies for detergent removal from concentrated bacterial culture supernatants containing 0.2% (w/v) Chaps. Dialysis removed 95% of Chaps and the addition of detergent-affinity beads to the dialysis buffer resulted in 97% removal of Chaps. Gel-filtration chromatography removed 99.9% of Chaps, while a detergent-affinity bead chromatography column removed 99.99%. Overall, gel-filtration chromatography was the most convenient and economical method for the one-step removal of the zwittergent from complex biological mixtures. 相似文献