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Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.  相似文献   

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Previous research has shown that caffeine and a<15-min nap effectively and separately reduce sleepiness in drivers for I hr. In the present study, we examined in 12 sleepy individuals the treatments combined, taken during a 30-min break, prior to a longer (2 hr) continuous monotonous afternoon drive in a car simulator. Nonnap comparisons were 200 mg caffeine only and placebo. For placebo, driving incidents. Subjective and electroencephalographic measures of sleepiness all reflected a mid-afternoon peak'. This peak was significantly reduced by caffeine and eliminated by the combined treatment, which reduced incidents to 9% of placebo levels versus 34% of placebo levels for caffeine alone. Naps comprising “nonsleep dozing” were still effective.  相似文献   
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Reduced activity of the red-cell sodium-potassium pump in human obesity   总被引:10,自引:0,他引:10  
Looking for evidence of reduced energy use in the cells of obese persons, we measured the numbers of sodium-potassium-pump units in erythrocytes from a group of 21 obese human subjects and found them to be reduced by 22 per cent as compared with those of nonobese controls (P <0.001). The cation-transport activity of the pump, as measured by 86rubidium uptake by the cells, we also reduced in parallel with decrease in pump units. An increased concentration of sodium in the red cells of obese subjectes was also found (9.6 +/- 0.7 vs. 7.1 +/- 0.6 mmol per liter of cells; P<0.01). This finding demonstrates independently the physiologic importance of reduced numbers of sodium-pump units and reduced pump activity as measured by ouabain binding and rubidium transport, respectively. The magnitude of the reduction in the number of pump units was found to be negatively correlated with the percentage of ideal body weight (r = 0.56, P<0.001); this observation suggests a possible role of abnormalities of the sodium pump in the pathophysiology of obesity.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Die Deutsche Rentenversicherung (DRV) hat entsprechend dem Sozialgesetzbuch&nbsp;VI den Auftrag, die Erwerbsfähigkeit...  相似文献   
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BACKGROUND: Although acute cholecystitis is one of the most common indications for abdominal surgery in patients with acquired immunodeficiency syndrome (AIDS), previous studies have reported disappointingly high morbidity and mortality among those patients who have undergone cholecystectomy. The aims of this study were to analyze the indications for and the outcome of cholecystectomy performed for acute cholecystitis in patients with AIDS. METHODS: We retrospectively reviewed the hospital charts of 53 patients with AIDS who underwent open or laparoscopic cholecystectomy from 1992 to 1997. Statistical analysis using the chi-square, Student's t, and Fisher exact tests was conducted to determine whether cause of cholecystitis, type of surgical approach, and CD4+ T-lymphocyte count influenced outcome. RESULTS: The clinical findings and imaging by ultrasonography were always reliable in establishing diagnosis and guiding treatment of acute cholecystitis. Open cholecystectomy was performed in 24 patients (45%). The procedure was begun laparoscopically in 29 patients (55%) and converted to open in 4 (14%). The pathologic findings showed acalculous cholecystitis in 19 patients (36%) and cholelithiasis in 32 (60%). Morbidity was 34% and mortality was 2%. Type of operative approach, cause of cholecystitis, and CD4+ T-lymphocyte count (greater or less than 50 cells/mm3) did not significantly affect morbidity and mortality. The length of hospital stay was significantly influenced by the CD4+ T-lymphocyte count. CONCLUSIONS: These findings suggest that in most patients with AIDS, laparoscopic or open cholecystectomy may be performed with significant but acceptable morbidity and low mortality.  相似文献   
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Journal of Autism and Developmental Disorders - Autism spectrum disorders (ASD) are associated with high services use, but European data on costs are scarce. Utilisation and annual costs of 385...  相似文献   
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