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41.
McCann Barbara S.; Bovbjerg Viktor E.; Curry Susan J.; Retzlaff Barbara M.; Walden Carolyn E.; Knopp Robert H. 《Canadian Metallurgical Quarterly》1996,15(1):61
Adult men and women (N?=?8,748) were given blood cholesterol tests and completed a measure of fat intake and a staging questionnaire that assessed readiness to adopt a cholesterol-lowering diet. Eligibility for the trial was based on plasma cholesterol levels and self-reported dietary intake. Of 772 eligible participants, 545 (70.6%) agreed to join. In multivariate analyses, joiners did not differ from nonjoiners by age, total cholesterol levels, or self-reported dietary fat intake. Women were more likely than men to join the study. Individuals in the preparation stage (defined on the basis of a staging algorithm derived from the transtheoretical model of change) were more likely to join the trial than were precontemplators. An understanding of the determinants of participation in a dietary intervention may be important in the enhancement of high-risk individuals' acceptance of recommendations to make dietary changes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
A comparison of self-reported drug use with a urine drug screen in a working population: Correction.
Bharucha-Reid Rodabe; McCann Daisy; Schork M. Anthony; Foxman Betsy; Bass Alan; Fraser Winifred; Cook Sandra; Kaufmann Rachel 《Canadian Metallurgical Quarterly》1996,4(2):150
Reports an error in the original article by R. Bharucha-Reid et al (Experimental and Clinical Psychopharmacology, 1995, Vol 3 [3], 280–286). Rachel Kaufmann was inadvertently misspelled. (The following abstract of this article originally appeared in record 1996-92908-001.) This study summarized information on 162 workers who completed urine screen and self-report concerning drug use. It is the first to compare self-report of drug use in the workplace with a urine screen in which individual participant (nonaggregate) data were used. The findings indicate that agreement between the 2 methods of drug detection, although statistically significant, is at best only moderate. The level of agreement was consistent for segments of the sample when divided by sociodemographic characteristics. Although urine screen may be the more reliable and accurate method of detecting prevalence of drug use, self-report must be considered to assess drug use histories and the role of other variables. These 2 methods should be considered as complementary assessment techniques; the appropriate method depends on the conditions and purposes of the drug use study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Two experiments with undergraduates examined the parameters of construct accessibility in depression. In Exp I, 30 depressed and nondepressed (the Beck Depression Inventory) Ss were required to name the colors of tachistiscopically presented depressed-content, neutral-content, and manic-content words. Because of the predicted accessibility and interference effects of the depressed-content words, depressed Ss were predicted to demonstrate longer response latencies to these words than to the non-depressed-content words. Results support the prediction: Nondepressed Ss did not demonstrate differential response latencies. In Exp II (30 Ss), a mood-induction paradigm was used to investigate whether the interference effects obtained in Exp I were due to temporary mood differences between depressed and nondepressed Ss or were a function of more stable depression-associated patterns of information processing. Although predicted group differences were obtained on a mood adjective checklist, no effects were found for task performance. Findings suggest that transient mood is not a sufficient explanation for the results obtained in Exp I. Implications for the understanding of both construct accessibility and depression are discussed. (68 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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45.
Wright P Garcia-Stewart CA Carey SJ Hindle FP Pegrum SH Colbourne SM Turner PJ Hurr WJ Litt TJ Murray SC Crossley SD Ozanyan KB McCann H 《Applied optics》2005,44(31):6578-6592
Design requirements for an 8000 frame/s dual-wavelength ratiometric chemical species tomography system, intended for hydrocarbon vapor imaging in one cylinder of a standard automobile engine, are examined. The design process is guided by spectroscopic measurements on iso-octane and by comprehensive results from laboratory phantoms and research engines, including results on temporal resolution performance. Novel image reconstruction techniques, necessary for this application, are presented. Recent progress toward implementation, including details of the optical access arrangement employed and signal-to-noise issues, is described. We present first cross-cylinder IR absorption measurements from a reduced channel-count (nontomographic) system and discuss the prospects for imaging. 相似文献
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47.
Accurate assessment is critical in planning appropriate therapeutic management of a patient with a vascular wound. However, several factors may inhibit wound assessment by trained professionals or subspecialists. Multiple co-morbidities and lack of transportation and finances contribute to problems with access to specialty clinics for both rural and urban patients with vascular disease. To assess the application of telemedicine in meeting the needs of rural patients with vascular disease, the vascular nurse clinician of a regional medical network was incorporated into a telemedicine research project that used a still-image transmission system known as the Picasso telephone, which allows a diagnostic quality image to be transmitted over a regular telephone line. Telephone consultation between sender and receiver occurs simultaneously at the time of image transmission. Because images can be collected and stored for future reference, this technology is commonly called "store and forward" technology. The application of advanced technology in a rural health care environment has the potential to reduce costs for both patient and managed care insurance plans, allow for expert consultation from distant centers, and promote collegiality and learning among professionals. 相似文献
48.
OBJECTIVES: Obesity is an important clinical problem, and the use of dexfenfluramine hydrochloride for weight reduction has been widely publicized since its approval by the Food and Drug Administration. However, animal and human studies have demonstrated toxic effects of fenfluramines that clinicians should be aware of when considering prescribing the drugs. Our purpose was to systematically review data on brain serotonin neurotoxicity in animals treated with fenfluramines and the evidence linking fenfluramines to primary pulmonary hypertension (PPH). DATA SOURCES: Archival articles and reviews identified through a computerized search of MEDLINE from 1966 to April 1997 using "fenfluramine(s)," "serotonin," "neurotoxicity," "behavior," "anorexigens," "weight loss," and "primary pulmonary hypertension" as index terms. STUDY SELECTION: Reports dealing with long-term effects of fenfluramines on brain serotonin neurons, body weight, and pulmonary function in animals and humans. DATA EXTRACTION: Reports were reviewed by individuals with expertise in serotonin neurobiology, neurotoxicity, neuropsychiatry, and pulmonary medicine and evaluated for appropriateness for inclusion in this review. DATA SYNTHESIS: Fenfluramines cause dose-related, long-lasting reductions in serotonin axonal markers in all the animal species tested and with all the routes of drug administration used. Doses of fenfluramines that produce signs of brain serotonin neurotoxicity in animals are on the same order as those used to treat humans for weight loss when one takes into account known relations between body mass and drug clearance. However, no human studies have been conducted, and the pathological and clinical potential for neurotoxicity in humans is unknown. Appetite suppressants-most commonly fenfluramines-increase the risk of developing PPH (odds ratio, 6.3), particularly when used for more than 3 months (odds ratio, >20). CONCLUSIONS: Fenfluramine and dexfenfluramine have been demonstrated to damage brain serotonin neurons in animal studies. It is not known if such damage occurs in humans or if there are clinical consequences. Use of fenfluramines is associated with an increased risk of PPH. Future studies should address the long-term consequences of prolonged use of fenfluramines. 相似文献
49.
UD McCann Z Szabo U Scheffel RF Dannals GA Ricaurte 《Canadian Metallurgical Quarterly》1998,352(9138):1433-1437
BACKGROUND: (+/-)3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy") is a popular recreational drug that selectively damages brain serotonin (5-HT) neurons in animals at doses that closely approach those used by humans. We investigated the status of brain 5-HT neurons in MDMA users. METHODS: We enrolled 14 previous users of MDMA who were currently abstaining from use and 15 controls who had never used MDMA. We used positron emission tomography (PET) with the radioligand carbon-11-labelled McN-5652, which selectively labels the 5-HT transporter. We analysed whether there were differences in 5-HT transporter binding between abstinent MDMA users and participants in the control group. Blood and urine samples were taken and tested to check for abstinence. FINDINGS: MDMA users showed decreased global and regional brain 5-HT transporter binding compared with controls. Decreases in 5-HT transporter binding positively correlated with the extent of previous MDMA use. INTERPRETATION: Quantitative PET studies with a ligand selective for 5-HT transporters can be used to assess the status of 5-HT neurons in the living human brain. We show direct evidence of a decrease in a structural component of brain 5-HT neurons in human MDMA users. 相似文献
50.
Kamat PC Roller CB Namjou K Jeffers JD Faramarzalian A Salas R McCann PJ 《Applied optics》2007,46(19):3969-3975
A high-resolution liquid-nitrogen-free mid-infrared tunable diode laser absorption spectroscopy (TDLAS) system was used to perform real-time measurement of acetaldehyde concentrations in human exhaled breath following ingestion of an alcoholic beverage. Acetaldehyde absorption features were measured near 5.79 mum (1727 cm(-1)) using a IV-VI semiconductor laser, a 100 m long path optical gas cell, and second- harmonic detection coupled with wavelength modulation. Acetaldehyde levels were measured with a minimum detection limit of 80 ppb for 5 s integration time. The variations in exhaled acetaldehyde levels over time were analyzed prior to and following ingestion of two different amounts of white wine. A method to calibrate acetaldehyde measurements internally using water vapor absorption lines was investigated to eliminate the need for system calibration with gas standards. The potential of a TDLAS system to be used as a noninvasive clinical tool for measurements of large volatile compounds with possible applications in cancer detection is demonstrated. 相似文献