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31.
In this study, the psychological symptom patterns of individuals with chronic pain on the Brief Symptom Inventory (BSI) were cluster analyzed. Cluster analysis was initially performed on a sample of 1,489 people with chronic pain and then cross-validated on a smaller sample of 244 people. A 2-cluster solution was deemed most appropriate. The clusters reflected low- and high-profile elevations on all BSI subscales. As part of their clinical evaluation, participants also completed the Pain Disability Index, the adjective list from the McGill Pain Questionnaire, and a modified version of the Posttraumatic Chronic Pain Test. Among persons in the smaller sample, high-profile participants were more likely to be involved in litigation, report a higher frequency of posttraumatic stress symptoms, and display poorer psychosocial functioning. The results suggest that the BSI subgroups are associated with psychosocial characteristics that may be important in terms of treatment planning and outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
A recent letter issued by HQ USAF/CV established a Double-R/Half-M policy for developing reliability and maintainability (R&M) requirements for the next generation of systems. This paper reviews the second portion of that policy, Half-M, and assesses the feasibility and implications of achieving the goal, as well as the programmatic elements considered most likely to assist in achievement of the goal. The paper discusses measures of maintainability, trends and concepts influencing maintainability, and the maintainability of current systems. The results of a survey of maintainability practitioners are presented as part of the assessment of the Half-M goal.  相似文献   
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The role of corticotropin-releasing factor (CRF), an endogenous neuropeptide, in modulating species-typical responses was examined in an unfamiliar open field containing a small chamber. Rats placed in this small chamber spent most of their time withdrawn in it. However, rats given an icv injection (20 μg) of α-helical CRF(9–41), a CRF receptor antagonist, emerged from the chamber and explored the unfamiliar open field. Results of additional studies with vehicle-treated rats suggest that reexposure reduces the threatening impact of an unfamiliar open field. CRF (300 ng) injected centrally, but not peripherally, before reexposure to the test environment significantly reduced exploration in the open field and increased a pattern of defensive-withdrawal into the chamber. Data suggest that whether defensive-withdrawal or exploratory behavior is exhibited may depend on CRF actions in brain systems that mediate the perception of threat in the environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
In Exp 1, infant rhesus monkeys were separated and then reunited with mothers, united with a male, or placed into an empty cage. Infants girned more when with mothers or the male than when alone. Girns declined over time when infants were united with the male. Coo rates were high when the infant was alone or with the male. Shrieks, barks, and fear-related behavior were higher with the male. In Exp 2, the vocalizations of infants were examined during separation when alone or when mothers or a male were in the same room. Infants cooed more when mothers or a male were present. Cooing increased over time, with a greater increase in the mothers' presence. Girns were given to both mothers and males, but more were given to mothers. Coos and girns are both affiliative vocalizations but are differentially modulated as infants cease cooing when they receive contact comfort. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
We studied the effect of premedication (1 microgram/kg fentanyl and 0.04 mg/kg midazolam 5 min before induction of anesthesia) on airway reactivity and hemodynamic stability during inhaled induction using desflurane in 10 ambulatory surgical patients. Eight patients who were anesthetized without premedication served as the controls. Induction and emergence were rapid and unaffected by premedication. End-tidal and inspired concentrations of desflurane at loss of consciousness were significantly reduced by premedication (10.1% end-tidal/14.1% inspired, no premedication, vs. 5.3% end-tidal/8.9% inspired, premedication). Airway irritability was markedly attenuated by premedication (100% no premedication versus 30% premedicated), as was apnea (37.5% no premedication versus 0% premedicated). We observed an increase in mean arterial blood pressure and heart rate after loss of consciousness (mean arterial pressure 103 vs 121 mm Hg, heart rate 73 vs 100 bpm) in the unpremedicated patients, whereas both groups demonstrated a decrease in mean arterial blood pressure with no change in heart rate when baseline values were compared to those at incision (103 vs 74 mm Hg, no premedication, 99 vs 81 mm Hg premedicated). Patient acceptability was satisfactory and unchanged by premedication. We recommend the use of such premedication when desflurane is used during the induction of anesthesia.  相似文献   
36.
Two unsymmetric polyunsaturated lecithins were allowed to air oxidize and the primary products of autoxidation were isolated and characterized. 1-Palmitic-2-linoleic-phosphatidylcholine undergoes significant oxidation after 16 hr at room temperature under air. A new phospholipid product may be isolated by reverse phase high pressure liquid chromatography (HPLC) and this HPLC fraction is shown to be made up of lipid hydroperoxides formed by free radical oxidation of the homoconjugated diene of the linoleate component of the lecithin. 1-Stearic-2-arachidonic-phosphatidylcholine undergoes a similar oxidation with the arachidonate polyunsaturated functionality being oxidized. The structure of the oxidation products was established by reduction of hydroperoxide with triphenylphosphine, snake venom hydrolysis of the C-2 ester, and HPLC analysis of the resulting hydroxy fatty acids or their methyl esters.  相似文献   
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Mitogaligin is a mitochondrion‐targeting protein involved in cell death. The sequence of the protein is unrelated to that of any known pro‐ or antiapoptotic protein. Mitochondrial targeting is controlled by an internal sequence from residues 31 to 53, and although this sequence is essential and sufficient to provoke cell death, the precise mechanism of action at the mitochondrial membrane remains to be elucidated. Here, by focusing on the [31–53] fragment, we first assessed and confirmed its cell cytotoxicity by microinjection. Subsequently, with the aid of membrane models, we evaluated the impact of the membrane environment on the 3D structure of the peptide and on how the peptide is embedded and oriented within membranes. The fragment is well organized, even though it does not contain a canonical secondary structure, and adopts an interfacial location. Structural comparison with other membrane‐interacting Trp‐rich peptides demonstrated similarities with the antimicrobial peptide tritrpcidin.  相似文献   
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