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991.
992.
Considerable differences on the frequencies of the mitochondrial 12S rRNA A1555G and tRNA(Ser(UCN)) A7445G mutations have been reported in different populations. Our screening of 168 patients coming from independent Turkish families with prelingual sensorineural non-syndromic deafness revealed three deaf children with A1555G (1.8%) but no examples of A7445G. One proband with the mitochondrial A1555G mutation has also evidence for right parietal infarct on a brain imaging study, for which common thrombotic mutations were found to be negative.CONCLUSION: This study shows that the mitochondrial A1555G mutation is among the significant causes of prelingual non-syndromic deafness in the Turkish population.  相似文献   
993.
Recent surgical experience in chronic constrictive pericarditis   总被引:7,自引:0,他引:7  
We reviewed the cases of 42 consecutive patients who underwent surgery for chronic constrictive pericarditis between January 1994 and January 2002, to determine causes, surgical techniques, mortality and morbidity rates, and improvement of functional capacity. Thirty-one of our patients were men (73.8%) and 11 were women (26.2%); their average age was 39.3 years. The pericarditis was tuberculous in 24 patients (57.1%), idiopathic in 10 (23.8%), rheumatic in 4 (9.5%), uremic in 2 (4.8%), and neoplastic in 2 (4.8%). In all cases, our approach was via median sternotomy. All anterior pericardium was resected from phrenic nerve to phrenic nerve. In 4 of 18 patients with calcific pericardial plaques, we could not develop a cleavage plane, so we left the plaques in place, reducing their size and relieving constriction by means of wedge incisions that reached the epicardium. No patient required cardiopulmonary bypass due to severe calcification or adhesion, but we did perform bypass with no difficulty in 5 patients who required additional cardiac surgery The early postoperative mortality rate was 11.9% (5 patients). In the 1st postoperative month, functional capacity improved dramatically: the number of patients in New York Heart Association functional class IV moved from 18 (preoperatively) to 1; in class III, from 20 to 6; in class II, from 4 to 13; and in class I, from 0 to 22. We recommend the median sternotomy approach for chronic constrictive pericarditis and consider cardiopulmonary bypass safe to use in indicated cases.  相似文献   
994.
BACKGROUND AND AIM: To evaluate the possible antifibrotic effects of two drugs, pentoxifylline (PTX) and interferon (IFN)-alpha as well as their combination, on a bile-duct-ligated rat hepatic fibrosis model. METHODS: Bile ducts of 34 female Wistar rats were ligated, and 24 bile ducts were sham operated. Bile-duct-ligated rats were divided into four groups, in which either sterile saline, IFN-alpha (100 000 IU/3 days a week), PTX (50 mg/kg/day) or IFN-alpha + PTX were administered. Sham-operated rats were treated at the same doses. On the 28th day, rats were decapitated to obtain blood for the measurements of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT) and bilirubins. Serum prolidase was assayed at the beginning and at the end of the study by the modified Chinard's colorimetric method. Liver prolidase was assayed after tissue homogenization. Liver collagen content was determined by the dye elution method described by Lopez de Leon. Morphometric-densitometric measurements of hepatic fibrosis were quantified by computerized image analysis. RESULTS: The AST, ALT, ALP, GGT and bilirubins, liver prolidase enzyme activity, collagen content and hepatic collagen surface density were found to be increased in bile-duct-ligated rats on day 28. There was no statistically significant recovery or even a change in collagen turnover rate in rats treated with alternate regimens applied in the study (P > 0.05). CONCLUSION: Pentoxifylline, IFN-alpha and their combination have no beneficial effect on experimental fibrosis induced by biliary obstruction.  相似文献   
995.
In the second article of this series we look at the planning stage of a project to produce patient information and the factors that should be considered. The paper also discusses guidelines for the production of patient information and legal aspects of information provision.  相似文献   
996.
Behavioral and molecular studies have established a link between drugs of abuse and the central melanocortin system, particularly the melanocortin 4 receptor (MC4-R). The present study expands this line of investigation to characterization of the neurochemical and behavioral interactions between MC4-R and the psychomotor stimulant, cocaine. The results demonstrate that repeated, but not acute, cocaine administration up-regulates MC4-R mRNA expression in the striatum and hippocampus, but not cerebral cortex. Pharmacological studies indicate that the up-regulation of MC4-R expression occurs via dopamine D1 and D2 receptor-dependent mechanisms. The D1/D2 antagonist haloperidol and the D2-selective antagonist eticlopride mimic the effect of cocaine on MC4-R expression. In addition, coadministration of a D1-selective antagonist, SCH 23390 [R-(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine], completely blocks the up-regulation of MC4 mRNA by cocaine, demonstrating that D1 receptor activation is necessary for this response. Moreover, the results demonstrate that cocaine treatment increases behavioral responses (grooming and locomotor activity) to infusions of a melanocortin agonist, indicating that up-regulation of MC4-R expression results in functional consequences. These data further support a role for the melanocortin-MC4-R neuropeptide system in the biochemical and behavioral effects of cocaine.  相似文献   
997.
Chronic pulmonary disease in rural women exposed to biomass fumes   总被引:10,自引:0,他引:10  
INTRODUCTION: Biomass (organic) fuels cause indoor air pollution when used inside dwellings. We evaluated the frequencies of chronic obstructive pulmonary disease (COPD) and chronic bronchitis (CB) among rural women using biomass fuels for heating and cooking and compared them to women living in urban areas where such fuels are not used. METHODS: From electoral lists we randomly selected 242 women living in rural areas near Kayseri, Turkey and 102 women living in apartments in the city having central heating and cooking with fuels other than biomass ones. Using a translated version of the American Thoracic Society questionnaire, with additional questions from the British Medical Research Council questionnaire, trained interviewers conducted personal interviews. They also collected information on fuels used for cooking and heating. All study subjects underwent a physical examination and measurement of pulmonary function. RESULTS: We found that rural women were younger than urban women (mean age [and standard deviation], 40.5 [14.1] yr v. 43.6 [11.9] yr). More urban than rural women were current (14.7% v. 4.5%, p < 0.001) or past (11.8% v. 1.2%, p < 0.001) smokers. CB was more prevalent among rural women than urban women (20.7% v. 10.8%, p < 0.03). Similarly, COPD was more prevalent in rural women (12.4% v. 3.9%, p < 0.05). Although the pulmonary function tests were within normal limits, FEV, values in rural women were found to be relatively low compared with those of urban women (p < 0.05). INTERPRETATION: Rural women exposed to biomass fumes are more likely to suffer from CB and COPD than urban women even though the prevalence of smoking is higher among the latter group.  相似文献   
998.
We reported five cases of Dyke-Davidoff-Masson syndrome (DDMS) with different clinical and radiological findings. The evaluated parameters were the location of the lesions, midline structural shift effect, pathological and morphological changes on the ipsilateral calvarium, paranasal sinuses and mesencephalon, presence of compensatory contralateral hypertrophy. With the help of both magnetic resonance (MR) and computerized tomography (CT) images, changing degrees of all the evaluated parameters were observed in all five of our patients. In conclusion, no relationship was found between parenchymal and calvarial changes and between the time after onset of the disease and amount of the morphologic and pathological changes.  相似文献   
999.
It has been suggested that determination of differential renal function (DRF)using technetium-99m dimercaptosuccinic acid (DMSA) may lead to overestimation of the function of an obstructed kidney in patients with excretion abnormalities owing to pelvic retention of DMSA. Recently published guidelines have recommended use of furosemide injection when calculating DRF in these particular patients. The aim of this study was to evaluate the effect of diuretic administration on the determination of DRF using DMSA scintigraphy. For this purpose, 19 patients, aged from 1 month to 69 years (19.4+/-24.8 years, 15 males, 4 females), in whom pelvic retention had been documented by diuresis scintigraphy were included in the study. DMSA scintigraphy was performed in all patients 2-4 h after injection and six planar images were obtained. Immediately after the standard study, furosemide was injected in all patients, and 30 min later the same number of images was obtained. DRF was calculated for each patient and from each DMSA study by using the arithmetic mean method. The difference between two studies (DMSA scintigraphy with or without furosemide administration and diuresis scintigraphy) was expressed as a percentage of the mean value of the two studies (the DRF value of the affected kidney was thus taken into account). The mean of the differences represented the systemic bias and the SD of the mean of the differences represented the precision of the technique. In seven patients, diuresis renography revealed an obstructive curve pattern. We did not observe any significant difference between the DRF values obtained before and after diuretic administration ( P>0.5). When we compared DRF values obtained from standard and from diuretic DMSA studies, the mean of the differences was only 0.3% and the SD was only 1.2%. There was also no significant difference in DRF between patients with the obstructive curve pattern and those with a dilated renogram curve pattern (with washout of activity during the second phase of the study) ( P>0.1). In conclusion, we did not observe interference from pelvicalyceal activity in patients with documented pelvic retention and infer that diuretic administration may be a useless intervention for improving the accuracy of determination of DRF.  相似文献   
1000.
Oblique osteotomy of the tibial tubercle is a preferred technique in patellofemoral disorders, resulting in a satisfactory clinical outcome. However, postoperative fractures of the proximal metaphysis of the tibia may often develop. An incomplete fracture of the lateral tibial plateau occurred in a 23-year-old female patient following an oblique osteotomy of the tibial tubercle. There was no history of trauma. The patient had undergone two operations in the same knee due to patellar instability. She also had bilateral high congenital hip dislocation. The correct diagnosis could only be made by computed tomography. Complete union was obtained following six weeks of plaster cast fixation. Due to inherent biomechanical limitations, complications may arise following oblique osteotomy of the tibial tubercle even adequate care is given to the surgical technique.  相似文献   
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