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971.
972.
Using a brief household food inventory as an environmental indicator of individual dietary practices. 总被引:3,自引:1,他引:2
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R E Patterson A R Kristal J Shannon J R Hunt E White 《American journal of public health》1997,87(2):272-275
OBJECTIVES: This study examined whether foods in household pantries are an indicator of house-hold members' diet. METHODS: In a random-digit-dial survey, the presence in the house of 15 high-fat foods was assessed with whoever answered the phone. A randomly selected household member was surveyed about diet-related behaviors (n = 1002). RESULTS: Individuals in the precontemplation stage of dietary change had more high-fat foods in their pantry than those in maintenance (means of 7.4 and 5.8, respectively). Individuals with low-fat pantries had an intake of 32% energy from fat vs 37% for those with high-fat pantries. CONCLUSIONS: Household food inventories are a practical and valid approach to monitoring dietary behaviors in community-based studies. 相似文献
973.
E Mayer P F Cardoso J D Puskas K De Campos T Oka I Dardick G A Patterson 《The Journal of thoracic and cardiovascular surgery》1992,104(1):180-188
Donor airway ischemia is a significant problem after clinical lung transplantation despite the use of omentopexy for accelerated local bronchial revascularization. Several growth factors have been shown to induce angiogenesis in vitro and in vivo. In the present study the quantitative effects on tracheal revascularization and epithelial regeneration of omentopexy and continuous local administration of basic fibroblast growth factor were investigated in a heterotopic rat tracheal isograft model. Tracheas were harvested from donor rats and heterotopically implanted into the omentum of syngeneic recipient rats. Animals were randomly assigned to study groups differing only in treatment of the tracheal segments: omental wrap for 2, 7, or 14 days; omental wrap plus continuous local administration of basic fibroblast growth factor for 7 or 14 days; or omental wrap plus local application of saline for 7 or 14 days. Two, 7, or 14 days after the animals were put to death, the vascularity of the tracheal segments and attached omentum and the tracheal epithelial morphology were assessed in a blinded fashion with use of light microscopy and morphometric image analysis. Vascularity in tracheal segments treated with basic fibroblast growth factor was significantly (p less than 0.05) greater than in control tracheas after 7 and 14 days. Epithelial regeneration was also improved in the basic fibroblast growth factor-treated groups at days 7 and 14 (p less than 0.05). We conclude that continuous local administration of basic fibroblast growth factor enhances early revascularization of tracheal segments induced by omentopexy and accelerates epithelial regeneration in a heterotopic rat tracheal isograft model. 相似文献
974.
C M Hsieh G J Mishkel P F Cardoso H Rakowski S C Dunn J Butany R D Weisel G A Patterson J D Cooper 《The Annals of thoracic surgery》1992,54(1):104-110
Combined heart-lung transplantation has been used for end-stage primary pulmonary hypertension. Experience with single-lung transplantation for other conditions suggested that associated severe right ventricular dysfunction resulting from increased afterload would recover after placement of a satisfactory lung allograft. Early experience with the application of single-lung transplantation for pulmonary hypertension supports this contention. We devised a reversible canine model of chronic progressive pressure-overloaded right heart failure by pulmonary artery banding to study the echocardiographic, hemodynamic, and pathological reversibility of the failing right heart. Clinical right heart failure was defined as the development of ascites and pleural effusions. Right heart failure developed in 23 dogs 67 to 348 days after banding, and they were divided into two groups to determine its early and long-term effects. Group 1 dogs (n = 11) were either sacrificed immediately after the onset of right heart failure (n = 5) or unbanded (n = 6); group 2 dogs (n = 12) were maintained in right heart failure for 3 months and then either sacrificed (n = 6) or unbanded. Unbanded dogs in both groups were observed for 4 additional months before sacrifice. A control group of 6 normal dogs was sacrificed for pathological comparisons. After unbanding, the right ventricular systolic pressure fell from 97 +/- 17 mm Hg (group 1) and 88 +/- 31 mm Hg (group 2) to 44 +/- 11 mm Hg and 47 +/- 13 mm Hg, respectively. Despite this persistent gradient across the pulmonary artery, echocardiographic and hemodynamic measures of right ventricular function returned to normal, albeit more slowly in the group 2 dogs.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
975.
976.
Y Cottin JM Doise V Maupoil M Tannière-Zeller F Dalloz M Maynadié MK Walker P Louis PM Carli JE Wolf and L Rochette† 《Fundamental & clinical pharmacology》1998,12(2):236-241
Summary— Free radical species have been implicated as important agents involved in myocardial ischemic and reperfusion injuries. Superoxide is capable of mobilizing iron from ferritin and the released iron can cause hydroxyl formation from H2O2. The aim of this study was to evaluate the time-dependent increase in lipid peroxidation assessed by plasma thiobarbituric acid reactive substances (TBARS) and the relationship between lipid-peroxidation and the iron status. Peripheral venous blood samples were obtained from 17 men with acute myocardial infarction (AMI) before thrombolytic treatment (T0***) and 1, 2, 3, 4, 8, 12, 16, 20, 24 and 48 hours after commencing fibrinolytic treatment. The concentration of TBARS, the parameters of iron metabolism, serum myoglobin, creatine kinase, and creatine kinase-MB were measured. Early reperfusion was judged by regression of sinus tachycardia (ST) elevation and reduction of chest pain. Recanalization of coronary artery was evaluated by a late coronary angiography 24–96 hours after thrombolysis. After thrombolytic therapy, the TBARS level was raised from 2.98 ± 0.80 (T0***) to 4.57 ± 1.24 (peak), and decreased to 2.96 ± 0.40 nmol/mL plasma at T48 (T0 vs peak: P < 0.001, peak vs T48: P < 0.001, TO vs T48: NS). The mean time of the peak was observed at 9.7 ± 7.5 hours. The iron increased significantly from 0.67 ± 0.34 (T0) to 1.15 ± 0.52 mg/L (peak), and returned to the pre-reperfusion to levels: 0.53 ± 0.28 UI/L at T48 (T0 vs peak: P < 0.001, peak vs T48: P < 0.001, TO vs T48: NS). The mean time of the peak was observed at 9.4 ± 7.3 hours. In return, no correlation was found between the increase of plasma creatine-kinase activity, myoglobin and iron or between the biochemical markers and time of fibrinolytic therapy. The results confirmed the importance of the temporal relationship between lipid peroxidation and iron status after thrombolytic therapy. Our results are in agreement with the concept that antioxidant agents used in association with thrombolytic therapy might be useful. 相似文献
977.
978.
S H Keshavjee D I McRitchie T Vittorini O D Rotstein A S Slutsky G A Patterson 《The Journal of thoracic and cardiovascular surgery》1992,103(2):326-328
Improved lung preservation with a low-potassium dextran-containing solution has been previously demonstrated. In a subsequent study, it was shown that dextran 40 contributes significantly to this improved preservation. In the current in vitro study, human neutrophils suspended in lung preservation solutions (low potassium with dextran and low potassium without dextran) were stimulated to produce superoxide radicals. The presence of dextran in the solution did not significantly alter the amount of superoxide measured in the assay (low potassium with dextran, 4.149 +/- 0.144 nmol/10(6) cells/20 min; low potassium without dextran, 3.896 +/- 0.215; p greater than 0.2). This suggests that dextran 40 did not appreciably scavenge superoxide radicals, nor did it alter the production of superoxide radicals by stimulated neutrophils. Thus the significantly improved lung preservation seen with the use of dextran 40 is probably not mediated by a superoxide radical scavenging process. 相似文献
979.
According to the US Centers for Disease Control, the majority of new HIV infections are the direct result of unprotected sexual relations between serodiscordant individuals. Thus, the development of behavioral interventions to increase the safer sex practices of HIV-positive individuals has the potential to reduce the number of new infections. Currently, less than 1% of the total US population is infected with HIV. Targeting behavioral interventions to this smaller group of HIV-positive individuals has the potential for making cost-effective reductions in the number of new infections. Despite reports that some HIV-positive individuals continue to engage in high-risk behaviors, interventions designed to prevent secondary transmission of HIV are rare. In this era of highly active antiretroviral therapy (HAART), interventions for HIV-positive individuals are more critical than ever to address the unique challenges and issues they face regarding disclosure and partner notification, use of HAART and sexual risk behavior, and HIV-related stigma. Although a growing number of reports document the efficacy of sexual risk reduction interventions for HIV-positive individuals, to date none of these studies have focused on drug-using populations. This article focuses on sexual risk reduction interventions for HIV-positive men who have sex with men (MSM), the largest group of HIV-positive individuals in the United States. It reviews factors associated with high-risk behaviors and discusses some findings from research with HIV-positive methamphetamine users, including (1) data from a small qualitative study and its implications for the development of new interventions, and (2) baseline data from an ongoing large-scale study of the efficacy of a theory-based sexual risk reduction intervention for HIV-positive methamphetamine-using MSM. The article concludes with a discussion of future research issues, including, for example: Can sexual risks be reduced in the context of active drug use? Are different patterns of drug use, or specific drugs, associated with increased risk behavior? How do gender, race, and culture relate to the efficacy of specific interventions? 相似文献
980.
Vaginal swabs from 299 hospital and general practitioners' patients were examined for Gardnerella vaginalis by Gram film and by culture, G. vaginalis was isolated in 12% of cultures. Comparison between the 'clue' cell and culture methods suggested that the former is a rapid, acceptable routine screening method for the detection of G. vaginalis. The value of the traditional method of identifying G. vaginalis by sensitivity testing is questioned. All specimens were also examined by Gram film and culture, for the presence of Mobiluncus spp, which was detected in 8.4% of specimens by Gram film but only 0.7% by culture. From a questionnaire returned by 84% of clinicians, metronidazole was found to be the most commonly used antimicrobial agent for the treatment of G. vaginalis, and in all but one case appeared to be clinically effective. 相似文献