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41.
Dynamic precautions in the early diagnosis and treatment of hospital acquired pneumonias are necessary because of their high mortality. In these patients, invasive diagnostic approaches may be needed since clinical and radiological findings and other non-invasive approaches frequently fail to establish the diagnosis. Thirty eight patients were prospectively included in the study. Average age of patients was 45.5 +/- 16.4 years; 31 were males (81.6%) and 7 (18.4%) were females. Pneumonia was detected in 9 (23.7%) cases during the first five days and in 29 (76.3%) cases after the fifth day of admission to the hospital. Bronchoscopic interventions diagnostic purpose were carried out in 25 (65.8%) patients. The culture results were negative in 7 (18.4%) cases. While more than one pathogen was determined on the cultures of 16 (42.1%) patients only one pathogen was isolated in the cultures of 15 (39.4%) cases. The frequently isolated pathogen on cultures was Staphylococci (45.4%). Other pathogens were Enterobacter spp., Pseudomonas spp., Escherichia coli, Serratia and Streptococcus pneumoniae according to their frequency on cultures. High resistance rates to the third generation cephalosporins were determined. Eleven of 17 deaths in 38 pneumonia cases were attributable to pneumonia. As a conclusion, isolation of pathogen and antibiotic resistance should be determined in the cases with hospital acquired pneumonia. Invasive diagnostic interventions were not avoided when necessary. Although pro-BAL and PSB methods were expensive, their use in selected cases may prevent unnecessary antibiotic use and contribute to a decrease in mortality rate.  相似文献   
42.
The purpose of the present study was to test endothelial function and to determine if plasma homocysteine levels are associated with endothelial injury in patients with Behcet's disease (BD). Flow-mediated dilation in patients with BD was smaller than that of control subjects (p = 0.001), and mean plasma homocysteine levels in patients with BD were significantly higher (p = 0.0001). On regression analysis, only mean plasma homocysteine concentration was independently related to flow-mediated dilation (F = 5.7, p = 0.001).  相似文献   
43.
Six patients with severe metabolic alkalosis were treated with intravenous hydrochloric acid (HCl) infusion. HCl was given through a central venous catheter, at a concentration of 0.1 mEq per ml. At least two of the following criteria were considered for initiation of the therapy: An arterial pH of greater than 7.45, a base excess (BE) of greater than +7 mmol/L, a PaCO2 of greater than 50 mmHg. The HCl amount was calculated using the BE formula, however, two thirds was infused for avoiding excessive acid loading. Patients were monitored by the blood gases, serum electrolytes, hemoglobin, hematocrti, bilirubin determinations and blood smear findings. While a significant decrease was noticed in pH and BE values, moderate changes were detected in PaCO2 due to different ventilatory status of the cases. All laboratory test results remained within normal limits and no complication was encountered. The adventage of the therapy is that less volume is needed for the correction of alkalosis, particularly in the cases requiring fluid restriction. HCl therapy, moreover, is a safe and time-saving method because of having rapid response to the treatment in the critically ill surgical patients.  相似文献   
44.
45.
Vertical thickness of cutaneous and subcutaneous lesions cannot be assessed accurately by simple examination. To achieve this ultrasonography was performed preoperatively and ruler assessment postoperatively. These measurements were then compared and evaluated using the Wilcoxon test. The results were not statistically significant (p=0.6592, z=0.4410). Cutaneous and subcutaneous ultrasonography is a simple, quick, accurate method of assessing lesion thickness. Received: 29 April 1997 / Accepted: 7 July 1997  相似文献   
46.
Vascular involvement in Beh?et's disease.   总被引:8,自引:0,他引:8  
Beh?et's disease (BD) is a multisystem disorder characterized by recurrent oral and genital ulcerations with uveitis. At onset it may present with manifestations of vascular involvement instead of the classical triad. We analyzed 137 patients with BD and 38 had vascular involvement with a prevalence of 27.7%. Male to female ratio was 4.4 and associations of positive pathergy test (76.3%) and eye lesions (57.8%) were higher compared to patients without vascular involvement. Patients with subcutaneous thrombophlebitis were more likely to develop major venous occlusions (22.2%) in the lower extremities and inferior vena cava. Arterial lesions were less frequent features constituting 12.0% of vascular complications in BD.  相似文献   
47.
The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.  相似文献   
48.
Introduction Although a variety of nutritional indices have been found to be valuable in predicting patient outcome when used alone, there is no consensus on the best method for assessing the nutritional status of hospitalized patients. Therefore, the aim of this study was to assess the nutritional status of a cohort of patients who underwent major elective surgery using the Nutritional Risk Index (NRI), Maastricht Index (MI), Subjective Global Assessment (SGA), and Mini Nutritional Assessment (MNA) to determine the best possible nutrition screening system in surgical practice. Methods The study population consisted of 460 patients who underwent major elective surgery between December 1999 and March 2002. Each patient had a complete set of the three nutritional assessment techniques (NRI, MI, SGA); in addition, the MNA was performed in patients older than 59 years of age. One of the coauthors who was unaware of the nutritional assessments assessed the patients for postoperative morbidity and mortality. Complications were classified as major or minor and as infectious or noninfectious. To assess the predictive value of the assessment techniques, likelihood ratios were calculated for the various strata of each method. The odds ratio and receiver operating characteristic (ROC) curves were also calculated to describe and compare the diagnostic value of each of the four nutrition indices. Results Twenty patients died during the study period. No complications occurred in 329 of the 460 patients; 42 patients suffered from two or more complications. The frequency of malnutrition was found to be 58.3%, 63.5%, and 67.4% as assessed by the SGA, NRI, and MI, respectively. Morbidity rates, especially severe infectious and noninfectious complications, were significantly higher in malnourished patients in all nutritional indices. The likelihood ratio was well correlated with the risk categories of every nutritional index. The area under the ROC curves revealed that each scoring system proved to be significantly powerful in predicting the morbidity (infectious and noninfectious severe morbidity) and mortality. However, no differences were detected among the nutritional indices in 460 patients. The odds ratio for morbidity between the well nourished and malnourished patients was 3.09 [95% confidence interval (CI), 1.96–4.88], 3.47 (95% CI, 2.12–5.68), 2.30 (95% CI, 1.43–3.71), and 2.81 (95% CI, 0.79–9.95) for the SGA, NRI, MI, and MNA, respectively. All indices except the MNA were significantly predictive for morbidity. The odds ratios were not statistically different among the indices. Conclusions Our findings revealed that all nutritional assessment techniques can be safely applied to the clinical setting with no significant difference in predictive value. We therefore strongly recommend the use of any of these techniques to improve the outcome of surgical care. Meanwhile, further investigations are needed, and much effort must be given to find the best method for assessing nutritional status. This work was presented at a conference of the European Society for Clinical Nutrition and Metabolism (ESPEN), August 31 to September 4, 2002, Glasgow, UK.  相似文献   
49.
L-carnitine is a quaternary amine that is essential for the normal oxidation of long-chain fatty acids by mitochondria. It is known that L-carnitine and its derivatives prevent the formation of reactive oxygen species, scavenge free radicals and protect cells from peroxidative stress. Oxygen-derived free radicals and lipid peroxidation products play a critical role in the pathogenesis of ethanol-induced gastric mucosal injury. The aim of the present study was to determine the effect of L-carnitine on lipid peroxidation induced by ethanol in the rat stomach. In our study, gastric mucosal injury was induced by the intragastric administration of 1 ml of absolute ethanol. Test compounds were given to rats by gavage 30 min before the ethanol administration. The animals were killed 60 min after the administration of ethanol. The stomach of each animal was removed. Mucosal damage was evaluated by macroscopic examination, histological analysis and by measurement of lipid peroxidation and glutathione activity. The intragastric administration of ethanol induced hyperemia and hemorrhagic erosions in the rat stomachs. L-carnitine significantly prevented gastric ulcerogenesis induced by ethanol and decreased the ulcer index. Plasma and gastric lipid peroxidation that was increased significantly by ethanol was decreased after treatment with L-carnitine. Ethanol treatment decreased significantly the gastric glutathione levels, and pretreatment with L-carnitine increased them significantly. Based on these data, the beneficial effects of L-carnitine on ethanol-induced gastric mucosal injury may be attributed to its antiperoxidative effects.  相似文献   
50.
We have studied the effects of three antioxidants and amrinone, an inotropic agent, against vancomycin-induced nephrotoxicity in rats by investigating renal function and morphology. Thirty adult female Sprague Dawley rats (168-234 g) were divided into six groups. A saline-treated group served as control. The other five groups were treated for 7 days with vancomycin alone or in combination with alpha-lipoic acid, Ginkgo biloba extract 761, melatonin or amrinone. On day 8, all the rats were sacrificed by decapitation, kidney tissues were excised immediately and blood and kidney samples were collected. Blood urea and creatinine, kidney tissue malondialdehyde levels, and kidney superoxide dismutase and glutathione (GSH) peroxidase activities were measured. The kidneys were also examined for histological changes. Vancomycin administration led to increased urea, creatinine and malondialdehyde levels and decreased superoxide dismutase and GSH peroxidase activities. Co-administration of alpha-lipoic acid, Ginkgo biloba extract, melatonin or amrinone with vancomycin prevented the increases in the urea, creatinine and melondialdehyde levels and also resulted in higher superoxide dismutase and GSH peroxidase activities. The antioxidants and AMR improved the renal pathology compared to rats treated with vancomycin alone (P<0.05). These results indicate that the three antioxidants and amrinone have potential protective effects against vancomycin-induced nephrotoxicity, which might in part be due to inhibition of free oxygen radical production. Amrinone was the most effective drug as judged on the basis of the pathological findings.  相似文献   
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