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51.
Arvanitis DA Papadakis E Zafiropoulos A Spandidos DA 《Lung cancer (Amsterdam, Netherlands)》2003,40(1):55-66
Using PCR-based microsatellite DNA analysis with 48 markers we examined sputum and bronchial washing for genetic alterations compared with lymphocyte extracted DNA from 124 lung cancer patients and 36 healthy donors as normal control. Microsatellite alterations (MA) in at least one locus were detected in all cancer patient-derived specimens but only in 22.2% of the healthy donors. Loss of heterozygosity (LOH) was detected in bronchial washings from 101 non-small cell lung cancer (NSCLC) predominantly on 17p13.1-p13.3 (69.7%), 9p13.3-p24.1 (63.3%), 1p34.2-p36.22 (48.5%), 13q12.1-q13.1 (47.7%) and 3p22.3-p23 (42.7%). In bronchial washings from 23 small cell lung cancer (SCLC) LOH was detected mostly on 3p22.3-p23 (88.6%), 17p13.1-p13.2 (82.3%), 5q32-q33.1 (66.6%), 13q12.2-q13.1 (65.6%) and 9q22.33-q31.3 (52.9%). The different LOH patterns indicate that different genetic background may be responsible for the different physiology of NSCLC and SCLC. The fractional allele loss (FAL) mean value of all cancer specimens was 0.243+/-0.021 compared with 0.007+/-0.008 of healthy donors with a confidence interval (CI) 99.5%. Only seven out of 124 lung cancer specimens (5.2%) exhibited FAL value less than 0.083, the highest was observed in the healthy donors group. FAL appears to be a likely indicator for lung cancer detection. Microsatellite instability (MIN) was detected in 8.7% of SCLC and 4.0% of NSCLC bronchial washings in at least three loci tested. LOH and MIN detection in sputum and bronchial washing from the same patient was 77.6%. Calculation of these indexes per marker exhibits significant variations that could be attributed to diffuse lung disorders or non-cancer specific genetic alterations. 相似文献
52.
Vrentzos GE Papadakis JA Vardakis KE Maliaraki N Stilianou K Arvanitis A Sratigis S Alivanis P Margioris AN Ganotakis ES 《Journal of nephrology》2003,16(4):535-539
BACKGROUND: High serum levels of total homocysteine (tHcy) are common in dialysis patients with end-stage renal disease (ESRD). We assumed that these patients may have decreased response to conventional folic acid (FOL) and vitamin B12 (B12) administered orally. This study aimed to evaluate the efficacy of an intravenous (i.v.) B12 regimen in ESRD patients and compare it with the conventional regimen. METHODS: We designed an open label, crossover, non-randomized study of 72 ESRD patients. Our patients were hemodialyzed in two hospitals (HOSP1 and HOSP2). In HOSP1, patients were on 1 mg of FOL and 600 micog of B12 orally for 3 months, and then switching to 1 mg of B12 i.v. for 3 additional months, while the FOL dosage was constant. In HOSP2, patients received the same treatment in reverse. RESULTS: Patients in HOSP1 (n = 37) after i.v. B12 treatment, had significantly lower tHcy (p < 0.001) and FOL (p < 0.05) serum levels, compared with those at the end of oral B12 treatment. On the contrary in HOSP2 patients, serum tHcy levels increased significantly (n = 35, p < 0.0001) when i.v. was switched to oral treatment. There was a significant inverse correlation between tHcy and B12 (p < 0.0001) at the end of the i.v. treatment period; while treatment there was no correlation between tHcy and FOL serum levels. At the end of the oral treatment period, there was no significant correlation between tHcy and B12 serum levels, while tHcy and FOL serum levels had a significant inverse correlation (p = 0.002). CONCLUSIONS: Our results suggest that ESRD patients on dialysis have 'B12 resistance', and that they should have, in addition to their FOL therapeutic regimen, i.v. B12 treatment to reduce their elevated tHcy levels. 相似文献
53.
Issidorides MR Havaki S Chrysanthou-Piterou M Arvanitis DL 《Ultrastructural pathology》2000,24(6):399-405
A temporal lobe ganglioglioma, surgically removed from an 8-year-old body, and a human brainstem at the level of locus coeruleus (LC) were processed for light microscopy (LM), with formalin fixation and paraffin embedding, and for electron microscopy (EM) with glutaraldehyde fixation, potassium permanganate postfixation, phosphotungstic acid-hematoxylin block-staining, and epoxy-resin embedding. The paraffin sections were stained with toluidine blue O/rhodamine B and observed under epi-fluorescence. The thin sections for EM were viewed directly without further staining. The neuronal neoplastic cells of ganglioglioma and the neurons of LC are known to produce catecholamines. Both also contain spherical protein bodies (pb), cellular markers that identify catecholamine neurons in humans. The ultrastructural characteristics of the pb in LC were compared with those of the pb in neoplastic ganglion cells. These bodies had an identical ultrastructure, in both tissues, consisting of electron-lucent core surrounded by an electron-dense thin rim. The rhodamine B-stained sections also emphasized the identical morphology of the pb in ganglioglioma and LC. Based on the EM comparison, these brightly fluorescing spherical bodies are ideal markers for identifying in LM, the clusters of large neoplastic cells, representing neurons, which are the most important clue to the correct diagnosis of gangliogliomas. 相似文献
54.
At birth, premature infants of 25-29 weeks gestation, at high risk for development of neonatal respiratory distress syndrome (RDS), were given a single dose (90 mg) of calf lung surfactant extract (CLSE) by intratracheal instillation. The frequency and severity of RDS were assessed with use of a simple radiographic scoring system in which pulmonary parenchymal densities and the prominence of the air-bronchogram effect were used as indicators of widespread atelectasis. Radiographs were obtained in surfactant-treated and control infants within the first 90 minutes of life as part of an initial evaluation of their pulmonary status. Subsequent examinations were performed at less than 24 hours and less than 48 hours of age. Radiographic assessment of lung disease compared consistently with coordinated data on oxygen and mean airway pressure requirements of the infants. Both indicated a significantly decreased frequency and severity of RDS in the infants treated with surfactant. The results provide supporting evidence of the effectiveness of exogenous lung surfactant replacement in mitigating RDS in very premature infants. 相似文献
55.
Reject analysis: a pilot programme for image quality management. 总被引:1,自引:0,他引:1
T N Arvanitis P M Parizel H R Degryse A M De Schepper 《European journal of radiology》1991,12(3):171-176
The radiographic film wastage and the different parameters affecting this wastage were analysed for a 9-week period at a 600-bed University Hospital. An overall reject rate of 7.6% was found. The different reasons for rejection were evaluated, while retake rate, relation between working experience of the personnel, amount of rejected films and total film wastage in surface (m2), were registered and analysed. 相似文献
56.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
57.
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60.
JE Barberie DG Connell PL Munk DL Janzen 《Journal of Medical Imaging and Radiation Oncology》1999,43(3):355-357
Muscle and nerve injuries in the hand may be difficult to detect and diagnose clinically. Two cases are reported in which magnetic resonance imaging showed ulnar nerve injury and intrinsic hand muscle denervation. The clinical, anatomical and radiological features of injury to the deep motor branch of the ulnar nerve and associated muscle denervation are discussed and illustrated. 相似文献