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BACKGROUND: Preoperative dietary counseling (PDC) before bariatric surgery is mandated by a growing number of insurance payers. Their claim is that PDC improves outcomes and postoperative compliance. We compared outcomes of GBP patients undergoing a mandatory 13 weeks of PDC (n = 72) to a contemporaneous group of patients with no such requirement (no-PDC; n = 252) who underwent operation between January 2000 and December 2002. METHODS: The PDC and no-PDC groups were characterized by similar male:female ratios (1:4 vs 1:4.6), mean age (42 years), mean body weight (324 lb vs 309 lb), and mean body mass index (BMI) (52 kg/m2 vs 50 kg/m2). The PDC group had a higher incidence of obstructive sleep apnea compared with the no-PDC group (41% vs 28%; P < .04) but otherwise the two groups had similar incidences of obesity-related comorbidities. The presurgery dropout rate was 50% higher in the PDC group than in the no-PDC group (28% vs 19%; P < .05). RESULTS: At 1 year follow-up, the no-PDC patients had a statistically greater percentage excess weight loss (67% vs 60%; P < .0001), lower BMI (32 vs 35; P < .015), and lower body weight (197 vs 218; P < .01). Resolution of major comorbidities, complication rates, 30-day postoperative mortality, and postoperative compliance with follow-up were similar in the two groups. CONCLUSIONS: The data demonstrate that insurance-mandated PDC is an obstacle to patient access for surgical treatment of severe obesity and has no impact on weight loss outcome or postsurgical compliance. PDC should be abandoned by the insurance industry.  相似文献   
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BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
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Behavioral state-specific changes in human hippocampal theta activity   总被引:1,自引:0,他引:1  
Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms.  相似文献   
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Cognitive evoked potentials and disorders of recent memory   总被引:1,自引:0,他引:1  
P3 potentials evoked by spoken words were recorded from seven patients with disorders of recent memory and seven age-matched controls. Inclusion criteria included a clearly identifiable P3 to pure tone stimuli. Absence or marked decrement of P3 to word stimuli was seen in the patients even though they could perform the word task. The results are consistent with an encoding disorder and failure in elaboration of information processing.  相似文献   
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To investigate the effect of moderate obesity on ventilatory responses to graded exercise, we compared the ventilatory responses of ten moderately obese (35 +/- 5 percent body fat) and nine leaner women (22 +/- 2 percent body fat) during walking on a treadmill with incremental increases in percent grade. Speed remained constant at 3.0 mph. In the obese women, VO2 in l/min and ml/FFW/min, fb (b/min), VE (l/min), and HR were significantly greater (P less than 0.05) at all four absolute workloads. At 10.0 and 12.5 percent grade, VO2 (ml/kg/min) was smaller and VE/VO2 was greater in the obese women. The difference in VE/VO2 suggests a lower ventilatory threshold for the obese women. Percent VO2 max and R (VCO2/VO2) were significantly different at 12.5 percent grade only. When VO2 was divided by HR (oxygen pulse), the two groups were not significantly different at any of the four workloads tested. The groups were compared further at workloads representing approximately 55, 65, 75, and 85 percent of VO2 max. HR was not significantly different at any of the four relative exercise intensities. VE was significantly greater in the obese at 85 percent of maximum only (P less than 0.05) and fb was significantly greater at 55, 75, and 85 percent of maximum. Whereas cardiorespiratory responses of moderately obese women are increased at absolute workloads when compared to that of leaner women, HR is similar at comparable intensities of exercise. VE is also similar at comparable intensities of exercise below ventilatory threshold but fb is greater. The effect of the higher fb on exercise tolerance is unknown.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A randomized controlled trial of sedation in the critically ill   总被引:2,自引:0,他引:2  
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children.  相似文献   
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