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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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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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Summary. Bone mineralisation during and after limb lengthening procedures on the femur or tibia using unilateral fixators has been monitored quantitatively using dual energy X-ray absorptiometry (DEXA). We measured the bone mineral density (BMD) prospectively in the newly formed callus, in the bone adjacent to the callus and in the proximal femur. In twenty-one patients we showed a typical course with a peak value at 4 – 6 weeks after beginning distraction and a minimum value at maximum distraction. In the consolidation period the BMD in the distraction gap increased until the fixator was removed. The BMD in the regenerated bone increased faster in the regions of interest (ROI) opposite the fixator compared to those near it. Dynamisation caused more homogeneous regeneration equalising V BMD in the different ROIs. The BMD in the proximal femur of the leg which was operated on decreased to 67% and in the opposite leg to 87% of the preoperative value. DEXA provides a precise and quantitative assessment of callus and bone mineralisation during limb lengthening and helps in understanding what is happening during these procedures.
Résumé. Le processus de la minéralisation peut précisément être étudié d’une manière quantitative pendant et après la distraction du cal au moyen de l’absorptiométrie en énergie-binaire (DEXA) en créant une petite radioexposition. Des patients (n = 21) avec une distraction du cal, auxquels nous avons mesuré prospectivement la densité minérale de l’os (bone mineral density = BMD) dans et autour du cal nouvellement formé, étaient traités avec des fixateurs externes unilatéraux. La minéralisation a montré une courbe typique avec une première pointe de valeur [0,365 +/– 0,196 g/cm 2 (30,9% de la première valeur)] à 4 – 6 semaines après le début de la distraction. Une valeur minimale apparut à la distraction maximale. Dans la période de consolidation la BMD est montèe jusqu’au moment de l’enlèvement du fixateur à 1,020 +/– 0,234 g/cm2 (87%). La minéralisation du cal, mésurée grace à la technique des ?regions of interest (ROIs)?, augmenté plus vite aux ROIs éloignées qu’aux ROIs très proches du fixateur. De la dynamisation du fixateur résulte une vitesse de minéralisation plus homogène. Nous considérons la DEXA comme une méthode précise pour étudier les processus de la minéralisation et du développement du cal pendant la distraction avec un fixateur unilatéral. En tenant compte des limites de la technique, la DEXA – qui nous livre des valeurs quantitatives – nous aide à comprendre ce qui se passe pendant la distraction.


Accepted: 11 July 1996  相似文献   
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Laparoscopic Cholecystectomy for Acute Cholecystitis: Prospective Trial   总被引:23,自引:0,他引:23  
p < 0.00001) and for hydrops (28.5%) and empyema of the gallbladder (28.5%) ( p = 0.004). The difference in conversion between the group with acute necrotizing (gangrenous) cholecystitis and the two groups with hydrops and empyema of the gallbladder was not statistically significant ( p = 0.07). The complication rates of acute cholecystitis, hydrops, empyema of the gallbladder, and gangrenous cholecystitis were 9.0%, 9.5%, 14.0%, and 20.0%, respectively ( p = NS). Patients with an operative delay of 96 hours or less from the onset of acute cholecystitis had a conversion rate of 23%, whereas a delay of more than 96 hours was associated with a conversion rate of 47% ( p = 0.022). The complication rate was 8.5% in the laparoscopic group and 27% in the converted group ( p = 0.013). Patients over 65 years of age, with a history of biliary disease, a nonpalpable gallbladder, WBC count over 13,000/cc, and acute gangrenous cholecystitis were independently associated with a high LC conversion rate; male patients, finding large bile stones, serum bilirubin over 0.8 mg/dl, and WBC count over 13,000/cc were independently associated with a high complication rate following laparoscopic surgery with or without conversion. Generally, LC can be performed safely for acute cholecystitis, with acceptably low conversion and complication rates. Different forms of cholecystitis carry various conversion and complication rates in selected cases. LC for acute cholecystitis should be performed within 96 hours of the onset of disease. Predictors of conversion and complications may be helpful when planning the laparoscopic approach to acute cholecystitis.   相似文献   
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols.  相似文献   
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