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71.
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BACKGROUND/AIMS: Catheterization of the femoral vein is a safe and recommended method of temporary access for haemodialysis. In some patients, however, because of the lack of other possibilities, it is necessary to maintain long-term femoral cannulation. The aim of the study was to evaluate the frequency of stenosis after prolonged femoral cannulation. METHODS: The 24 patients incorporated in the study were divided into two groups. Group 1 consisted of 10 end-stage kidney failure patients (four females and six males, aged 32-75 years, average 55.6+/-13.6 years) in whom femoral catheters were maintained for less than 2 weeks (5-14 days, average 9.3+/-3.6 days). Group 2 included 14 chronic haemodialysis patients (six females and eight males aged 23-65 years, average 49.5+/-13.27 years). The time of catheter maintenance ranged from 2 to 16 weeks (average 6.4+/-4.2 weeks). Femoral and iliac vein status was evaluated using magnetic resonance imaging. RESULTS: A feature of venous stenosis of both the femoral and iliac veins was disclosed in four patients in whom femoral cannulation lasted more than 4 weeks. There were no stenoses in group 1. CONCLUSION: Long-term femoral cannulation for more than 4 weeks may be associated with a significant risk of stenosis in the femoral and/or external iliac veins.  相似文献   
73.
Early results (12 weeks after surgery) of the lumbar spinal stenosis operative treatment were assessed in the group of 36 patients (aged 40-65 years). In 72% of patients posterior fusion was applied. In the results evaluation lumbar pain, low extremities pain, neurogenic claudicat ion, sensory disturbances and functional status were taken in account. A significant decrease in low extremities and lumbar pain was observed. Some sensory disturbances after operative treatment did not affect general high patients assessment of the performed surgical procedures (positive 80.5% cases).  相似文献   
74.
75.
Formation of intrachondral vessels (cartilage canals) in the proximal femoral epiphysis was studied in 13- to 22-week-old human fetuses using a corrosion casting technique and scanning electron microscopy. Several successive morphological stages of angiogenesis occurring inside the hyaline cartilage were distinguished. The process of cartilage vascularization starts with the formation of hairpin loops sent off from the perichondrial vascular network into the adjacent cartilage. A capillary glomerulus is then formed at the leading end, and the entire vascular unit grows in length, assuming a mushroom-like shape. Its further elongation is accompanied by a backward expansion of the capillary network which surrounds a pair of main vessels (arteriole and venule) like a manchette. The subsequent branching of such primary vascular units proceeds according to the same morphological patterns. The resulting tree-like vascular formations become interconnected via their lateral branches. This study clearly supports the invasion theory of cartilage canal formation.  相似文献   
76.
77.
The new technique, polymerase chain reaction, used for in vitro DNA fragments amplification is described. The conditions of the reaction and methods of data analysis are discussed as well as the usefulness of this technique in research and medical practice.  相似文献   
78.
This article contains the review and the critical discussion of studies of T and B lymphocytes in chronic B-cell lymphocytic leukaemia. It is not explicitly known now, which stage of differentiation of lympho-haemopoietic cells undergoes malignant transformation in CLL-B. Basing on VDJ recombination activity it is supposed that some cases derive from the stem cell, others--from B lineage cells.  相似文献   
79.
Gc subtypes were analyzed by isoelectric focusing on thin-layer polyacrylamide gel. In the sample of the Polish population including 278 persons, six Gc phenotypes were encountered: 1S, 1F-1S, 1F, 2-1S, 2-1F, 2 with the following frequencies: 0.342, 0.151, 0.014, 0.360, 0.072 and 0.061. Frequency of Gc1S was 0.597, Gc1F - 0.126 and Gc2 - 0.277. It was shown that a group system of the Gc protein in the Polish population was in good agreement with Hardy Weinberg equilibrium.  相似文献   
80.
We have studied the sensitivity of human pulmonary mast cells to some immunological and nonimmunological histamine releasers. The pulmonary mast cells were obtained by bronchoalveolar lavage (BAL) of nonasthmatic patients. Mast cells constituted about 1% of total cell population and were morphologically intact. These cells were highly sensitive to the challenge with anti-human IgE. They responded to calcium ionophore A23187, polymyxin B and concanavalin A, however the magnitude of histamine release was low. BAL mast cells were unresponsive to the compound 48/80.  相似文献   
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