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Human T lymphocyte subsets, identified by means of OKT3, 4 and 8 monoclonal antibodies, were isolated by a fluorescence activated cell sorter (FACS IV) and analyzed for distribution of alpha-naphthyl acetate esterase (ANAE) activity. As compared to OKT8+ lymphocytes a higher proportion of OKT4+ lymphocytes was ANAE-positive exibiting a spot or dot-like pattern in the cytoplasm. OKT8 and 4 positive subsets showed a similar ANAE distribution in diffuse granular form. Although OKT4 and OKT8 populations presented a different ANAE dot-like reactivity, this marker did not allow as clear a distinction between them as that reported for TG and TM lymphocytes.  相似文献   
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A recently discovered variant in the prothrombin gene (20210A) has been found in approximately 5–10% of patients with venous thromboembolism. It has been shown that patients with this variant present with high levels of prothrombin in plasma and this is maintained to be the most likely mechanism by which the risk of thrombosis is increased. We have evaluated prothrombin antigen levels in 50 carriers of the 20210A allele and compared with non-carriers. 327 subjects were subdivided according to deficiency status and previous thrombosis. 30 symptomatic and 20 asymptomatic carriers had increased mean prothrombin levels as compared to symptomatic ( n  = 178) or asymptomatic ( n  = 99) non-carriers. The percentage of subjects with prothrombin levels above cut-off values of 1.15 u/ml or 1.30 u/ml was significantly higher in carriers of the prothrombin variant as compared to non-carriers, regardless of a previous thrombosis. However, among non-carriers the percentage of those with prothrombin levels above cut-off values was significantly higher in the group of symptomatic as compared to asymptomatic individuals. In conclusion, increased prothrombin antigen levels, as detected by a specific ELISA, were found among 50 symptomatic and asymptomatic carriers of the 20210A prothrombin variant as well as among a large group of symptomatic non-carriers. The data are in agreement with those found by using functional tests for the determination of prothrombin levels in these patients.  相似文献   
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Patients who have undergone surgical repair of congenital heart diseases are usually not allowed to participate in competitive sports. In the present study we report our long-term experience with 9 male athletes aged 17 to 23 years who participate in competitive sports after undergoing surgical repair of ostium secundum atrial septal defect at a median age of 9 years; six of them play football and three of them volleyball. Competitive sport activities began 1 to 5 years after surgical repair. The mean duration of follow-up is 88 +/- 26 months. Sport fitness was granted on the basis of the following criteria: 1) a normal physical examination; 2) a normal working capacity on exercise test; 3) no arrhythmias on exercise test and Holter monitoring, recorded also during sport activities; 4) a normal M-mode and two-dimensional echocardiography, including the normalization of right ventricular size; the persistence of an abnormal ventricular septal motion did not exclude sport fitness. Recently we also performed Doppler and color Doppler echocardiography and gated equilibrium radionuclide angiography at rest and during exercise. We studied left ventricular diastolic filling through the pulsed wave Doppler evaluation of transmitral flow and measured cardiac output by continuous wave Doppler echocardiography during exercise test in the supine position. We also performed exercise test and M-mode, two-dimensional, Doppler and color Doppler echocardiography in a control group made up of 15 athletes (10 football players and 5 volleyball players). The exercise duration at graded treadmill exercise test (according to the Carù protocol), the maximal heart rate and the maximal systolic blood pressure were, respectively, 12.9 +/- 0.8 min, 192 +/- 10 beats/min and 198 +/- 12 mmHg. Left ventricular end-diastolic dimension, mass and ejection fraction (single-plane area-length method) were 50.3 +/- 2.8 mm, 210 +/- 38 g and 65 +/- 6%. M-mode right ventricular diastolic dimension was 23.4 +/- 1.6 mm; the right ventricular maximal diastolic diameter and area obtained on two-dimensional echocardiography from the apical four chamber view were 44.1 +/- 3.6 mm and 25 +/- 3.8 cm2 respectively. The evaluation of transmitral flow showed the following data: E velocity 77 +/- 12 cm/sec, A velocity 45 +/- 6 cm/sec, E/A ratio 1.7 +/- 0.3, the isovolumic-relaxation period 72 +/- 8 m/sec and the deceleration half-time of the early rapid filling 71 +/- 10 m/sec. A trivial tricuspid regurgitation was detected in 6 subjects; the peak velocity of the regurgitant jet was less than 2.1 m/sec.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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