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61.
PURPOSE: To assess the variability among clinicians in the delineation of mediastinal and hilar lymph node stations (LNS) according to the published recommendations in the treatment planning of elective nodal irradiation for lung cancer. METHODS: Nine observers delineated on axial CT scans of five cases the LNS according to the guidelines of the published Atlas. Next, the Volumes of Consensus (VC)--fitting strictly the guidelines--for each LNS and case were collectively defined. Volume of Intersection (VI) as the overlap of the Delineated Volume (DV) for each LNS, case and observer with respective VC was computed. The Concordance Index (CI) for respective LNS and observers was defined as "VI/VC x 100%". The Discordance Index (DI) for respective LNS and observers was defined as "(1-VI/VD) x 100%". RESULTS: Mean values of CI and DI for all observers were 69% and 36%, respectively. For five radiation oncologists who used to work as a team the ways of delineation were similar. The poorest reproducibility was shown for LNS 5, 7, 10R, and 10L. CONCLUSIONS: Although detailed guidelines are used there is still substantial room for improvement. More training in the use of the Atlas is recommended.  相似文献   
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Background  

Patients after successful repair of coarctation of aorta (CoAo) are at risk of hypertension at rest and associated end-organ damage. The aim of the study was to assess arterial stiffness and function in adults after coarctation repair in relation to descending aorta (AoD) residual coarctation and patient’s age at operation.  相似文献   
63.
Background: Immunomodulating enteral nutrition in the perioperative period may reduce postoperative complications in cancer patients. Little is known if this effect translates to the better survival. The aim of study was to assess the impact of postoperative immunomodulating enteral nutrition on postoperative complications and survival of gastric cancer patients. Methods: A group of 98 gastric cancer patients was randomly assigned for postoperative immunomodulating enteral nutrition n = 44 (Reconvan, Fresenius Kabi, Bad Homburg, Germany), or standard enteral nutrition n = 54 (Peptisorb, Nutricia, Schipol, The Netherlands). Postoperative complications, mortality, 6-mo and 1-yr survival were analyzed. Results: The overall postoperative morbidity did not differ between the groups. The rate of pulmonary complications (excluding pneumonia) was significantly lower in immunomodulation group (0% vs 9.3%, p = 0.044), as well as 60-day mortality (0% vs. 11.1%, p = 0.037). There was no difference in 6-mo and 1-yr survival between the groups. Conclusions: Postoperative immunomodulating enteral nutrition may reduce respiratory complications and postoperative mortality in comparison to standard enteral nutrition. Despite this effect, it did not improve 6-mo and 1-yr survival in immunomodulation group. Probably the beneficial effect of immunomodulating enteral nutrition is too weak to be significant in such a number of patients.  相似文献   
64.
The glycaemic index concept has more and more supporters all over the world. Many years will no doubt pass before the beneficial impact of a low glycaemic index diet in the prevention of heart diseases is fully confirmed, but we already know that the risk of heart diseases is lower when we use such a diet. Additionally, the diet is consistent with the other dietary changes necessary in the prevention of heart diseases. The data resulting from epidemiological and clinical investigations show that a low GI diet facilitates body mass reduction and an improved lipid profile. However, we still need further research to learn more about many processes which influence carbohydrate and lipid metabolism and the determination of the role of various genetic and environmental factors.  相似文献   
65.
Increased calcium intake has been associated with lower body weight, BMI and adiposity, mostly in children, youth and women. In men results are inconclusive. In this study the relation between calcium intake and body weight and body fat in obese men was investigated. 200 men, the mean age 45.1 +/- 9.4 y, the mean BMI 33.2 +/- 4.8 kg/m2, were divided into 4 groups on the basis of their calcium/protein index. No significant differences in body weight, BMI, fat mass, percentage of body fat were found across subgroups and no significant correlations between calcium intake and body variables were stated. This study did not confirm the association between calcium intake and body weight and adiposity in men.  相似文献   
66.
OBJECTIVE: To evaluate patients without prior pulmonary disease after cardiac surgery and to determine whether resistive unloading by automatic tube compensation, pressure support ventilation, and continuous positive airway pressure has different effects on oxygen consumption, breathing pattern, gas exchange, and hemodynamics. DESIGN: Prospective, randomized, controlled study. SETTING: Tertiary care, postoperative intensive care unit. PATIENTS: Twenty-one patients scheduled for open heart coronary artery bypass graft surgery. INTERVENTIONS: Each patient was ventilated with all three modes in random order. MEASUREMENTS AND MAIN RESULTS: Patients were ventilated in three modes, each applied for 30 mins according to computer-generated randomization: pressure support ventilation with 5 cm H2O, continuous positive airway pressure, and automatic tube compensation. Oxygen consumption was calculated by means of indirect calorimetry. The hypnotic state of the patients was monitored by Bispectral Index. For hemodynamic measurements, a fiberoptic pulmonary artery catheter was inserted. The main finding of our study was that oxygen consumption and breathing pattern (tidal volume and respiratory rate) did not differ significantly during automatic tube compensation and pressure support ventilation compared with continuous positive airway pressure (oxygen consumption, 170 +/- 29 vs. 170 +/- 26 vs. 174 +/- 29 mL.min.m, respectively; tidal volume, 466 +/- 132 vs. 484 +/- 125 vs. 470 +/- 119 mL, respectively; respiratory rate, 16 +/- 4 vs. 15 +/- 4 vs. 16 +/- 4 breaths/min, respectively). Automatic tube compensation and pressure support ventilation had no clinical effects on gas exchange and hemodynamic variables compared with continuous positive airway pressure. None of the variables differed significantly during the three ventilatory settings. CONCLUSION: In postoperative tracheally intubated patients with normal ventilatory demand, automatic tube compensation and pressure support ventilation with 5 cm H2O lead to identical oxygen consumption, breathing patterns, gas exchange, and hemodynamics. We, therefore, suggest that this group of patients does not need any additional positive pressure support from the ventilator to overcome the additional work of breathing imposed by the endotracheal tube during the weaning phase from mechanical ventilation.  相似文献   
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Fibrosis is the process accompanying majority of chronic diseases of liver, independent of etiological factor and leading to cirrhosis and hepatic failure. Monitoring fibrosis process by liver's biopsy is limited, so many attempts are undertaken to assess concentrations of definite proteins in blood, which could be easily accessible marker of intrahepatic process. It seems, that among others, determinations of blood concentration of aminoterminal propeptide of procollagen III--index of collagen's III synthesis and TGF-beta 1--cytokine of antiproliferative action and inhibiting hepatocytes' growth, yet inducing fibroblasts' growth and stimulating fibrosis process brings out such a possibility. The aim of the study was simultaneous determination of TGF-beta 1 and PIIINP concentration in blood of patients with chronic hepatitis B and C before interferone's therapy in comparison to healthy controls, assessment of the parameters in dependence on stage of liver fibrosis and determination of correlation between TGF-beta 1 and PIIINP. Studies were performed in 40 patients with chronic hepatitis B (CAH B) and 35 patients with chronic hepatitis C (CAH C). Significantly increased serum concentrations of TGF-beta 1 as PIIINP in both groups of patients (CAH B and CAH C; grading 2-3, staging 1-2) in comparison with control group was noted. Significant positive correlation of TGF-beta 1 and PIIINP serum concentrations in both groups of patients was observed. There was not significant changes in PIIINP serum levels in patients with hepatitis B and C in dependence on stage of liver fibrosis (staging 1 vs staging 2) but TGF-beta 1 serum levels was significantly increased in CAH B and C patients with higher stage of liver fibrosis process. On the base of obtained results, it seems that changes in TGF-beta 1 concentrations in blood reflect "grading" and "staging" and can be a marker of intensification of intrahepatic fibrosis process whereas PIIINP levels in blood have rather the relation with "grading".  相似文献   
70.
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