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BACKGROUND: Twenty percent of the long saphenous vein (LSV) grafts that are employed as coronary bypass conduits occlude during the first year after the operation. The aim of this study was to evaluate the morphological parameters of the LSV grafts before implantation as predictors for the early occlusion of the grafts. METHODS: Forty-two samples of LSV grafts were examined via light, transmission electron, and scanning electron microscopy and evaluated clinically and by angiography at 6 months and 2 years after the operation. Morphological parameters were statistically analyzed and examined for their significance on the viability of the vein grafts. RESULTS: Six (14.28%) of the examined grafts occluded within the first 6 months after the operation, and 11 grafts (26.19%) occluded within the first 2 years. The grafts that occluded at 6 months were characterized by thick intima (mean value, 206+/-32.29 vs. 67.44+/-10.17 in the group functioning normally and 98.42+/-34 in the group occluded within 2 years), low endothelial coverage (22.7+/-4.04 vs. 64.61+/-2.89 and 26.06+/-1.78 in the corresponding groups), and narrow lumen (46.73+/-9.69 vs. 527.18+/-45.78 and 204.26+/-16.5 in the corresponding groups). The presence of foam cells, edema, calcification, neovascularization, and thrombus in the lumen of the veins is frequently observed in the wall of the occluded vein grafts, whereas fibrosis does not seem to be related. CONCLUSIONS: LSV grafts with low endothelial cell coverage, stenosis of the lumen, and thick walls are at an increased risk of developing intrawall lesions that lead to early graft failure.  相似文献   
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An Opton cytophotometer was used for a comparative morphometric study on mesothelial and tumour cells obtained from pleural effusions. Tumour cells coming from malignant neoplasms with epithelial or mesenchymal origin were measured. Slides stained after Ambs X Gr?nemeyer and Smetana methods revealing RNP structures have been used. Both methods were valuable for nucleolar morphometry but the technical simplicity of the second one made it preferable. Nuclear and nucleolar surfaces as well as diameters and perimeters of nucleoli have been studied. Nucleolar/nuclear index, i.e. average number of the nucleoli per nuclear profile as well as nuclear/nucleolar surfaces ratio have been counted too. A clear difference of the average nucleolar size in tumour cells compared to that of mesothelial ones was established. The count of nuclear/nucleolar surfaces ratio-reveals that nucleolar enlargement in tumour cells is higher than nuclear one. In constant changes in the nucleolar/nuclear index was revealed in tumour cells.  相似文献   
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Background: The aim was to establish the predictors of early functional and structural vascular alterations (using intima-media thickness (IMT)) and flow-mediated vasodilation (%FMD) as well as to investigate the interrelationship between IMT and %FMD in asymptomatic, never-treated, severe hypercholesterolemia (HH). Methods: One hundred and twenty patients with asymptomatic, severe, untreated HH and 100 controls were included. ELISA was used for asymmetric dimethylarginine (ADMA) and cellular adhesion molecules, and fluid chromatography for total homocysteine (tHcy). Hewlett Packard SONOS 5500 with a 7.5 MHz transducer and MedicaSoft IMT software were used for evaluation of %FMD and IMT of common carotid artery (CCA). Results: Patients and controls differ with respect to all tested biomarkers (P < 0.05), except for P-selectin and E-selectin (P < 0.05). %FMD was lower in patients (P < 0.001). The IMT of the CCA was higher in patients (P < 0.001). Inverse correlations were found between %FMD and IMT mean and age, ADMA, Apo-B, Apo-B/Apo-A1, and tHcy. ADMA was established as the most important factor related to %FMD. Age and Apo-B were established as the most important factors related to IMT mean. An inverse correlation was established between %FMD and IMT mean (rxy= 0.546; P < 0.001)). If cases with IMT mean ≥1 were excluded, the correlation weakened. In patients with IMT mean ≥1 mm, the correlation did not change. Conclusion: In conclusion, asymptomatic, untreated patients with severe hypercholesterolemia are at high risk of having increased IMT of the CCA, especially if there is endothelial dysfunction, verified by %FMD of the brachial artery.  相似文献   
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The effect and side reactions of bromocriptin of the firm "Richter" were evaluated in this study. Fifteen women with interrupted pregnancy between 14 and 28 gestational week were explored. To prevent the onset of lactation treatment was started within a few hours after abortion in dosage 2.5 mg (one tablet) twice daily, for 14 days. The prolactin-lowering action began to take effect 2 hours after ingestion of the first tablet, peak after 5 hours, and maintained for 8-12 hours. In course of treatment 14 days in dosage two times daily, the lactation was inhibited in 100% of the cases, in 65% of them she was stopped at the first three days of therapy, in 15% of the cases she was stopped between 3rd and 7th day, and in 20%--after the 7th day of the treatment. The adverse reactions nausea, dizziness, vomiting, diarrhoea, constipation, headache and orthostatic hypotension were transitory. They were observed rarely, and during the first 3-5 days of treatment disappeared.  相似文献   
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