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51.
In this study, the authors examined the concentrations and mineralogical analyses of asbestos, and investigated mesothelioma risk in southeastern Anatolia, Turkey. They used a gravimetric dust sampler to collect samples from 2 villages and 2 asbestos mines (1 active). Samples were then evaluated by an X-ray diffractometer and an electron microscope. The authors found high concentrations of asbestos in an active mine (4.9 fibers[f]/cm3) and at a house that was plastered with asbestos (1.24 f/cm3) and had a very active population. They found a low concentration (0.0042 f/cm3) in indoor measurements taken in Armutova village, and an even lower concentration (0.000081 f/cm3) in the inactive mine environment. Outdoor measurements included a low concentration of 0.007 f/cm3 in the village environment, and a high concentration of 1.17 f/cm3 on the mine road during the passing of a sheep herd. The people in the region are continuously exposed to asbestos during normal activities. This cumulative exposure to asbestos carries sufficient risks for mesothelioma development.  相似文献   
52.
Control and streptozotocin-induced diabetic rats, as well as GK rats, received a single oral administration of either nateglinide (50 microg/g body wt.) or glibenclamide (1.0 microg/g body wt.). The plasma D-glucose and insulin concentrations, as well as the content of plasma, liver and pancreas in either nateglinide or glibenclamide were measured 60 min or 24 hours after the administration of these antidiabetic agents. At the 60th min, the plasma, hepatic and pancreatic content of nateglinide largely exceeded that of glibenclamide. At the 24th hour, however, the plasma concentration, as well as liver and pancreas content, of nateglinide became negligible, whilst that of glibenclamide exceeded the values recorded at the 60th min. A comparable pattern characterized the insulinotropic action and hypoglycemic effect of these two antidiabetic agents. This study thus emphasizes the vastly different pharmacodynamics of nateglinide and glibenclamide in both control and diabetic rats.  相似文献   
53.
Fifty-three consecutive children ages 6 to 14 with femur fractures treated with early percutaneous intramedullary fixation were evaluated retrospectively. The operation was performed within 24 hours in 50 patients and in the remainder after 48 hours. All patients were mobilized and allowed full weight-bearing in a functional brace in the early postoperative period. The average hospital stay was 4 days. The average follow-up was 24 months. There were no significant intra- or postoperative complications. An average overgrowth of 1.8 mm was measured using scanogram 24 months after surgery. In the authors' experience, this technique is highly effective for the treatment of children 6 to 14 years old with femur fractures. The main advantages of this method are early weight-bearing, immediate mobilization, short hospitalization, and fewer complications.  相似文献   
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CT fluoroscopy-guided percutaneous needle biopsies in thoracic mass lesions   总被引:5,自引:0,他引:5  
OBJECTIVE: We aimed to evaluate the usefulness of computed tomographic (CT) fluoroscopy guidance for transthoracic needle biopsies. METHODS AND MATERIAL: CT fluoroscopy-guided biopsies were performed in 81 patients with thoracic mass lesions. Interrupted CT fluoroscopy technique was used with 50-130 mA at 120 kV exposure parameters and slice thickness of 10 mm. We used aspirating needle in 41 patients, cutting needle in 28 patients, and both in 12 patients. We obtained adequate biopsy material in 69 patients at first attempt. Mean fluoroscopy time was 15.17 s and maximum procedure time was 18 min. RESULTS: Adequate samples for pathological diagnosis were obtained in all lesions. Pathological diagnoses were malignant in 41 patients, benign in 27 patients, and suspiciously malignant in 13 patients. There was no significant difference between diagnostic accuracy of the needles in malignant and benign lesions. Complications were observed in 11 patients (13.5%). DISCUSSION AND CONCLUSION: CT fluoroscopy-guided technique provides effective real-time needle biopsy in patients with small tumor size and with tumor located near blood vessels, and in non-compliant patients for diagnosing thoracic lesions.  相似文献   
56.
OBJECTIVE: Weight gain frequently occurs during treatment with clozapine. However, the pathophysiology of clozapine-induced weight gain remains unclear. The aim of this study was to investigate the influence of clozapine on hormones leptin and insulin in relation to body weight and composition measures to determine their contribution to clozapine-induced weight gain. METHOD: Data are reported on 19 patients with schizophrenia (11 women and 8 men) who completed 10 weeks of treatment with clozapine. Insulin levels, weight measurements, body mass index (BMI), and body composition measurements were evaluated at baseline and at the end of treatment. Leptin levels were assessed at baseline and after 4 and 10 weeks of treatment. Analysis of variance with repeated measures was used to evaluate changes in weight, body composition measures, leptin, and insulin. The Pearson correlations were used to assess the relationships between changes in hormone levels and weight along with body composition measurements. The correlations of change in Positive and Negative Syndrome Scale (PANSS) score with changes in hormone levels, weight gain and body composition measures were evaluated with Pearson correlations. RESULTS: Leptin and insulin levels did not show any significant alterations across time. The use of clozapine was associated with significant increases in BMI (F=19.8, P<.001), lean muscle mass (F=8.2, P=.01), and fat mass (F=15.4, P=.001), while total body fluid percentage (F=4.1, P=.05) significantly decreased. Improvement in PANSS scores was not correlated to change in leptin, insulin, weight, BMI, or body composition measurements. The change in leptin levels was correlated to change in body fat mass. CONCLUSION: The role of leptin in weight gain induced by clozapine might be a regulatory mechanism rather than being etiologic.  相似文献   
57.
Severe anemia, growth retardation, diabetes mellitus, cardiac disorders, and, infrequently, stroke are well-known complications of thalassemia major. We report a girl, age 7 years, 2 months, with beta-thalassemia major associated with chronic renal failure, diabetes mellitus, and cardiomyopathy in whom a silent stroke was noted during follow-up. She was diagnosed with thalassemia major at age 6 months, chronic renal failure at age 3 years, 3 months, and diabetes mellitus and cardiomyopathy at age 7 years. Although cranial computed tomography was found to be normal at the age of 3 years, 3 months, magnetic resonance imaging showed cerebral infarct in the right frontal region at 7 years, 2 months. A thrombophilic panel revealed increased factor VIII and decreased protein C concentrations. She died from disseminated intravascular coagulation at age 7 years, 9 months. We did not record any clinical findings of stroke during her follow-up. We think that diabetes mellitus, dilated cardiomyopathy, and increased factor VIII and decreased protein C concentrations led to the occurrence of cerebral infarct. In conclusion, we emphasize that children with thalassemia major should be monitored closely for stroke. We also suggest that stroke can show a silent progression in severely affected children, as in our case.  相似文献   
58.
BACKGROUND: Previous studies have reported a circadian variation of ventricular tachyarrhythmias. However, there is no detailed information of the daily distribution of ventricular tachycardia (VT) and ventricular fibrillation (VF) episodes. The purpose of this study was to evaluate the daily distribution of episodes of ventricular tachyarrhythmia in patients with implantable cardioverter defibrillators. MATERIAL/METHODS: We used data stored by last-generation implantable cardioverter-defibrillators (ICD) to retrospectively evaluate the circadian distribution of VT and VF in 70 patients with ICD. The distribution of tachyarrhythmias was categorized into four time zones: zone 1 (06:00-11:59), zone 2 (12:00-17:59), zone 3 (18:00-23:59), and zone 4 (00:00-05:59). RESULTS: During a follow-up of a mean of 3.1+/-1.3 years, a total of 791 ventricular arrhythmias were recorded from which 631 events were VT and 160 VF. A circadian variation of episodes of ventricular tachyarrhythmia was evident. The incidence of ventricular arrhythmia sharply increased in zone 1 (8.82+/-2.13, p<0.0001). Episodes of VT had peaks in zones 1 and 2 (7.44+/-2.03 and 2.70+/-0.65, p<0.001) and episodes of VF had peaks in zones 1 and 4 (1.38+/-0.39 and 1.30+/-0.51, p<0.011). No difference was observed between patients who used betablocker and those who did not. CONCLUSIONS: Malignant ventricular tachyarrhythmias have a circadian distribution. VT peaks occur in the morning and noon hours and VF peaks occurs at the night and morning hours. Betablocker and/or amiodarone usage do not alter this distribution.  相似文献   
59.
Odontology - In the last decade, demand for metal-free esthetic restorations has grown considerably due to the development of materials to fulfill the need for an esthetic prosthesis. We examined...  相似文献   
60.
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