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81.

Information

The 11th Meeting of the European Society for Paediatric Infectious Diseases (ESPID) 26–28 May 1993 Helsinki, Finland  相似文献   
82.
Summary We have studied the effects of clofibrate treatment on glucose tolerance and plasma insulin, plasma triglyceride, cholesterol and non-esterified fatty acid (NEFA) levels, and on various haematological variables (including plasma fibrinogen level, red cell flexibility, whole blood viscosity, and plasma -thromboglobulin level) in patients with mature-onset diabetes. Twenty-two patients (11 men and 11 women) were randomly allotted to treatment with clofibrate, 1 g twice daily, or a corn-oil placebo for 12 weeks, and then changed to the alternate medication for another 12 weeks. Half the patients took clofibrate in the first 12 weeks of the study, and half took the placebo. The patients stayed on their usual diet, and 13 also took tolbutamide before and during the trial. The trial was double-blind. At the beginning, middle and end of the trial fasting measurements were made, and plasma glucose, insulin, triglyceride, and NEFA concentrations were then measured repeatedly during the next 8 h (from 8.00 a. m. to 4 p. m.), to allow calculation of the mean 8-h concentration of these substances. In general, plasma concentrations of glucose, triglyceride, cholesterol, NEFA and fibrinogen were lower when the patients were taking clofibrate then when they were taking the corn-oil placebo, but higher when taking the placebo than at entry to the trial. We favour the explanation that clofibrate has lowered these concentrations, when compared with the placebo. The alternative interpretation, that 2 g per day of the placebo increases plasma concentrations of glucose, triglyceride, cholesterol, NEFA and fibrinogen, and that clofibrate has little effect, seems unlikely. The first interpretation, that clofibrate has a positive effect when compared with an inert placebo, has been adopted when interpreting the results. Clofibrate treatment led to a 15% lower fasting blood glucose level, and 11% lower mean 8-h glucose concentration than did placebo (p<0.01) but it did not significantly change plasma insulin concentration. The fasting and mean 8-hour concentrations of plasma triglyceride and fasting plasma cholesterol concentrations were reduced by clofibrate (by 44%, 33% and 10% respectively, p<0.05). Clofibrate decreased the fasting plasma NEFA level by 27% (p<0.01), and the mean 8-h plasma NEFA concentration by 23% (p<0.05). A weak relationship between the mean 8-h levels of plasma NEFA and plasma glucose (r=0.49, p<0.05) was consistent with the suggestion that the change in plasma glucose could, in part, be due to a change in NEFA concentration. The mean plasma fibrinogen concentration was decreased 23% by clofibrate (p<0.01). There was a positive correlation between the observed decrease during treatment and the baseline fibrinogen concentration (r=0.80, p<0.001), i. e. the greatest decrease occurred in those subjects with the highest plasma fibrinogen concentrations. Whole blood viscosity fell slightly, but erythrocyte flexibility was not significantly changed by clofibrate. The mean haemoglobin concentration and leucocyte count fell slightly during clofibrate treatment and the platelet count rose. -thromboglobulin was not affected. Clofibrate treatment was associated with rises in plasma albumin, urea, creatine kinase and aspartate aminotransferase, and falls in plasma bilirubin, -glutamyl-transpeptidase and alkaline phosphatase. Most of these changes occurred within the reference range.  相似文献   
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Determination of glomerular size-selectivity in the normal rat with Ficoll.   总被引:6,自引:0,他引:6  
Diffusion studies in vitro indicate that Ficoll behaves more like an ideal spherical molecule than does dextran, suggesting that Ficoll would be a better probe of glomerular pore size than the commonly used dextran. To examine the differences between these macromolecules in vivo, the fractional clearances of tritiated Ficoll and dextran were measured over a wide range of molecular sizes (Stokes-Einstein radius, rs, from 19 to 65 A) in normal euvolemic Munich-Wistar rats. Whole-kidney and single-nephron hemodynamic conditions were characterized through a combination of clearance and micropuncture measurements. The fractional clearance, or sieving coefficient (theta), for dextran significantly exceeded that of Ficoll at all molecular sizes examined, theta for dextran being approximately 10 times that for Ficoll for rs greater than 30 A. Thus, the results with Ficoll imply a more size-restrictive barrier than do the results with dextran. The values of theta for Ficoll approximated previously reported values for uncharged globular proteins. Although theta for Ficoll at rs = 35 A was much smaller than the corresponding value for dextran, it was still approximately 30 times greater than typical values of the filtrate-to-plasma concentration ratio reported for serum albumin (a polyanion) in the rat, in agreement with the concept that glomerular charge-selectivity normally plays an important role in the prevention of albuminuria. Three membrane-pore models were compared in their ability to represent the dextran and Ficoll sieving data. A lognormal pore-size distribution in parallel with a nonselective "shunt" pathway was found to be more effective than either an isoporous membrane with a shunt or a purely lognormal distribution. On the basis of these laboratory results and computations, Ficoll may be preferred over dextran in future studies of glomerular size-selectivity.  相似文献   
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STUDY DESIGN: A retrospective review of 244 adult spine instrumentation and fusion surgery cases (1994-1995) from one institution. OBJECTIVES: To ascertain the predictors of blood transfusions for adult patients undergoing different types of multilevel spine surgery. SUMMARY OF BACKGROUND DATA: Blood loss and transfusion requirements during and after multilevel spine surgeries have always been perceived as great. Identifying the predictors of blood transfusion with this type of surgery may aid in reducing the amount of blood loss and the transfusion requirements. METHODS: The charts of 244 adult patients who underwent multilevel spine surgery from January 1994 to July 1995 were retrospectively reviewed. RESULTS: A large percentage of patients required blood transfusion. The significant determinants for increased amounts of allogeneic red blood cell units transfused on the day of surgery using linear multiple regression modeling were low preoperative hemoglobin concentration, tumor surgery, increased number of posterior levels surgically fused, history of pulmonary disease, decreased amount of autologous blood available, and no use of the Jackson table (R2 = 0. 63). The significant determinants for an increased amount of autologous red blood cell units transfused on the day of surgery using linear multiple regression modeling were increased autologous red blood cells available, low preoperative hemoglobin concentration, and increased number of posterior levels surgically fused (R2 = 0. 60). CONCLUSION: The need for transfusion is associated with multiple factors, suggesting that a multifaceted, integrated approach may be necessary to reduce this risk.  相似文献   
88.
Risk factors for postoperative complications of benign goiter surgery have not been investigated systematically. To this end, a prospective multicenter study (January 1 through December 31, 1998) was conducted involving 7266 patients with surgery for benign goiter from 45 East German hospitals. High-volume providers (>150 operations per year) performed 69% (5042/7266), intermediate-volume providers 27% (50–150), and low-volume providers 4% (258/7266) of operations. Among the hospital groups, the pattern of thyroid disease did not vary significantly, but there was a trend that small-volume providers tended to perform more operations for uninodular goiter and high-volume providers treated more patients with Graves' disease and recurrent goiter. Extent of resection (p < 0.0001) and remnant size (multinodular goiter and recurrent goiter, p < 0.001), differed significantly, with total thyroidectomy being performed more often in hospitals with more than 150 operations compared to hospitals with an operative volume of less than 150 procedures per year. Despite the larger extent of resection and smaller remnant size, rates of recurrent laryngeal nerve (RLN) palsy or hypoparathyroidism were not increased. When the logistic regression analyses were fitted to evaluate the impact of risk factors on transient and permanent RLN palsy and hypoparathyroidism, larger extent of resection [relative risk (RR) 1.5–2.1] and recurrent goiter (RR 1.8–3.4) consistently evolved as independent risk factors. With hypoparathyroidism, additional significant factors included patient gender (RR 2.1–2.4), hospital operative volume (RR 0.8–1.5), and Graves' disease (RR 2.8). Unlike parathyroid gland identification during hypoparathyroidism, RLN identification (RR 1.6) significantly (p= 0.01) reduced permanent RLN palsy rates. The multivariate analyses clearly confirmed the pivotal role of routine RLN identification, independent of the extent of the thyroid resection. These findings might help hospitals with lower operative volumes to identify patients at increased risk whom they might consider for specialist care.  相似文献   
89.
Left ventricular hypertrophy (LVH) is a common finding in hypertensive autosomal dominant polycystic kidney disease (ADPKD) patients. There are few studies on the influence of blood pressure (BP) and nonhemodynamic factors on LVH in these patients. The aim of this study was to evaluate the relationship between BP, humoral and neurohormonal factors and left ventricular mass (LVM) in hypertensive ADPKD patients. In 20 hypertensive ADPKD patients, ambulatory BP was monitored for 24 h, left ventricular dimensions were estimated by echocardiography, and plasma renin activity (PRA), plasma noradrenaline (NA), angiotensin II (Ang II), aldosterone, atrial natriuretic peptide (ANP) and insulin-like growth factor I (IGF-I) were also determined. Twenty age- and sex-matched essential hypertensive subjects served as controls. Ambulatory BP and LVM index were similar in the two groups, although male ADPKD patients had higher LVM indices than their matched controls. Eight ADPKD patients (40%) and 6 essential hypertensives (30%) showed LVH. PRA, Ang II, aldosterone, ANP and IGF-I levels were similar in the two groups, but plasma NA levels were higher in ADPKD patients than in controls (281 +/- 158 vs. 160 +/- 62 pg/ml, p = 0.004). ADPKD patients with LVH did not differ from those without LVH with regard to humoral and neurohormonal parameters, but had higher ambulatory BP levels. In ADPKD patients, correlation analysis revealed a significant association between LVM index and 24-hour systolic and diastolic BP, but not with any of the hormonal factors evaluated. On multiple regression analysis, 24-hour diastolic BP was the only independent variable linked to LVM index. In conclusion, ambulatory BP is one of the most important determinants of LVM in hypertensive ADPKD patients. Further studies are warranted to elucidate the role of nonhemodynamic factors in the pathogenesis of LVH in this population.  相似文献   
90.
PURPOSE: To investigate the safety and tolerability and to explore the pharmacokinetic and pharmacodynamic profile of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with solid tumors that express epidermal growth factor receptor (EGFR). PATIENTS AND METHODS: This was a phase I dose-escalation trial of EMD72000 in patients with advanced, EGFR-positive, solid malignancies that were not amenable to any established chemotherapy or radiotherapy treatment. EMD72000 was administered weekly without routine premedication until disease progression or unacceptable toxicity. RESULTS: Twenty-two patients were treated with EMD72000 at five different dose levels (400 to 2,000 mg/wk). National Cancer Institute common toxicity criteria grade 3 headache and fever occurring after the first infusion were dose limiting at 2,000 mg/wk; thus, the maximum-tolerated dose was 1,600 mg/wk. No other severe side effects, especially no allergic reactions or diarrhea, were observed. Acneiform skin reaction was the most common toxicity, but it was mild, with grade 1 in 11 patients (50%) and grade 2 in three patients (14%). Pharmacokinetic analyses demonstrated a predictable pharmacokinetic profile for EMD72000. Pharmacodynamic studies on serial skin biopsies revealed that EMD72000 effectively abrogated EGFR-mediated cell signaling (eg, reduced phosphorylation of EGFR and mitogen-activated protein kinase), with no alteration in total EGFR protein. Objective responses (23%; 95% CI, 8% to 45%) and disease stabilization (27%; 95% CI, 11% to 50%) were achieved at all dose levels, and responding patients received treatment for up to 18 months without cumulative toxicity. CONCLUSION: Treatment with EMD72000 was well tolerated and showed evidence of activity in heavily pretreated patients with EGFR-expressing tumors. EMD72000 at the investigated doses significantly inhibited downstream EGFR-dependent processes.  相似文献   
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