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91.
Highly trained athletes show morphologic cardiac changes (ie, athlete's heart) that are the consequence of several determinants, including type of sport, gender, and, possibly, inherited genetic factors. The extent of physiologic cardiac remodeling may occasionally be substantial in highly trained athletes and may raise a differential diagnosis with structural cardiac disease, such as cardiomyopathies. In addition, athletes demonstrate a spectrum of alterations in the 12-lead electrocardiogram (ECG) pattern, including marked increase in precordial R-wave or S-wave voltages, ST segment or T-wave changes, and deep Q waves suggestive of left ventricular hypertrophy, that may raise the possibility of pathologic heart condition, but have also been viewed as a consequence of the cardiac morphologic remodeling induced by athletic conditioning. To evaluate the clinical significance of these abnormal ECGs, the authors compared ECG patterns to cardiac morphology and function (assessed by two-dimensional echocardiography in individual athlete) in a large population of 1005 elite athletes engaged in a variety of sporting disciplines. Forty percent of the athletes had abnormal ECGs, and a subgroup of about 15% showed distinctly abnormal and often bizarre patterns highly suggestive of cardiomyopathies, such as hypertrophic cardiomyopathy, in the absence of pathologic cardiac changes. Such alterations are likely the consequence of athletic conditioning itself and represent another potential component of athlete's heart syndrome. However, such false-positive ECGs represent a potential limitation to the efficacy of routine ECG testing in the preparticipation cardiovascular screening of large athletic populations.  相似文献   
92.
Trends in cancer mortality in Switzerland were analysed over the period 1980-2001, on the basis of the World Health Organization database. Appropriately developed correction factors were utilized for the period before 1995, to allow for spurious trends introduced by the change between the 8th and the 10th revisions of the ICD. Steady declines in cancer mortality were observed, particularly from the mid-1980s onwards. Over the last decade, the fall in overall age-standardized (world standard) cancer mortality was 11.1% in men (from 158.1 in 1990-1991 to 140.6/100,000 in 2000-2001) and 7.6% in women (from 91.6 to 84.7/100,000), and the decline was larger in truncated rates from 35 to 64 years (-18.0 and -9.7%). In men, all major tobacco and alcohol neoplasms have declined until the late 1990s but have levelled off over the last few years, reflecting recent trends in alcohol and tobacco consumption. The fall in male lung cancer mortality was 20% over the last decade (from 42.9 to 34.3/100,000). In contrast, lung cancer mortality in women has steadily increased by 38% between 1981 and 1991 and by 47% between 1991 and 2001, to reach 10.7/100,000 at all ages and 18.3 at age 35 to 64, due to increased prevalence of smoking in subsequent generations of Swiss women. Other sites showing substantial declines include stomach and colorectum in both sexes, (cervix) uteri and breast in women. Likewise, prostate cancer showed modest favourable trends after 1995. Steady declines were observed for leukaemias, Hodgkin's disease and testicular cancer, namely, the neoplasms most influenced by therapeutic improvements, while trends in lymphomas and myeloma showed no clear pattern.  相似文献   
93.
Betulinic acid is a triterpene with selective cytotoxicity against melanoma, neuroectodermal and malignant brain tumor cell lines. In this study the betulinic acid activity was evaluated, in comparison with doxorubicin, on different human neoplastic and non-neoplastic cell lines and on proliferating normal lymphocytes. Growth inhibition was evident in all the neoplastic cell lines independently on p53 status and histotype. Antiproliferative activity of betulinic acid was related to a cytotoxic effect on two p53 wild-type and on one p53 mutant cell lines and to a cytostatic effect on one p53 mutant melanoma clone. At the same concentrations, normal cells were unaffected indicating a selective effect of this agent. A cytotoxic activity of doxorubicin was evident on all the tested systems. In vivo experiments, performed on one of these cell lines, confirmed the antineoplastic activity of this drug. These data support further preclinical studies of betulinic acid not confined to melanoma and neuroectodermal tumors independently of p53 status.  相似文献   
94.
PURPOSE: To improve the 63% event-free survival (EFS) achieved before 1986 in Murphy's stage III to IV Burkitt's lymphoma (BL), both chemotherapy and supportive care were intensified. PATIENTS AND METHODS: From May 1987 to February 2001, 60 children, median age 9 years (range, 2.1 to 17 years), with advanced BL were enrolled onto two sequential institutional studies. From 1987 to 1992, 30 patients were stratified according to the absence (regimen IA, n = 19) or presence (regimen IB, n = 11) of bone marrow (BM) or CNS involvement. After 5-week cytoreductive chemotherapy consisting of vincristine, cyclophosphamide, doxorubicin, high-dose (HD) methotrexate (MTX), and intrathecal MTX or cytarabine, HD cytarabine and cisplatin were provided as a 4-day continuous infusion. Regimen IB was intensified by adding etoposide and HD ifosfamide and escalating MTX doses. Since 1992, regardless of BM or CNS status, 30 patients have been placed on regimen II, which is identical to IB but without ifosfamide. The scheduled duration of regimen II was 45 days. RESULTS: EFS and disease-free survival at 5 years are 81% +/- 5% and 87% +/- 5%, respectively, for 59 assessable patients (73% +/- 8% and 85% +/- 7% for regimen IA + IB, 89% +/- 6%, EFS and disease-free survival, for regimen II; median follow-up, 6.7 years; range, 0.6 to 13.5 years). Six patients, two of whom were receiving regimen II, died as a result of initial treatment failure or relapse, and five patients, none receiving regimen II, died as a result of treatment-related complications. CONCLUSION: This 45-day intensive chemotherapy program is the shortest schedule for disseminated BL and overcomes previously recognized risk factors such as BM and CNS infiltration.  相似文献   
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One hundred and twenty-one consecutive patients with monostotic Ewing's sarcoma (ES) were treated according to three consecutive combined modality programs from 1974 to 1986. Their 3-year progression free survival (PFS) rate from diagnosis of 59% was identical to the event free survival (EFS) rate, since all the 50 events occurring within 3 years from diagnosis were tumor recurrences. Primary tumor was treated with radiotherapy in 75 cases, surgical resection plus radiotherapy in 38, and radical surgery in 8. Chemotherapy was given to all patients and each program included adriamycin, vincristine, and cyclophosphamide ± dactinomycin. Median follow-up was 12 years, ranging from 6 to 19 years. The PFS rate decreased to 49% at 6 years and plateaued at 46% after the 7th year from diagnosis, even though some relapses were observed as late as 14 years from diagnosis. Second malignancies developed in 7 patients free from progressive ES and were represented by osteogenic sarcoma in previously irradiated bone in 4 cases and by breast carcinoma in 3. No other event but tumor relapse or second malignancy occurred in this series. EFS rate was 47% at 6 years and 39% at 12 years, further decreasing in the following years because of a number of late events. A continuous PFS longer than 7 years may be consistent with cure in the majority of patients with monostotic ES. However, these patients should be followed indefinitely because of risk of second malignancies. © 1994 Wiley-Liss, Inc.  相似文献   
98.
99.
Favourable outcome in 33 triplet pregnancies managed between 1985-1990.   总被引:1,自引:0,他引:1  
In this paper, we describe the outcome of 33 triplet pregnancies referred to us between 1985 and 1990. They were managed as follows: management at home as soon as the diagnosis was made, then hospitalization at 28 weeks' gestation. Progesterone and beta-mimetics were administered daily, a cesarean section was always performed. One late abortion occurred at 21 weeks. The rate of prematurity was 90.6%, mean gestational age at delivery was 34.1 +/- 3 weeks, and 62.5% of deliveries occurred between 34 and 37 weeks. Ninety-four fetuses were delivered alive. Mean birth weight was 1880 +/- 410 g. Fetal growth retardation rate was 61.8%, including 28 infants under the third centile and 31 under the 10th centile. Perinatal death rate was 4.16% including 2 in utero deaths and 2 neonate deaths. All infants are healthy except for one child with severe mental retardation. These results show that triplet pregnancies can be safely managed, and that selective first-trimester reduction in triplet pregnancies does not appear to be necessary.  相似文献   
100.
Summary Platelet antibody determination by the PF3 test was carried out in 96 thrombocytopenic patients with various disorders, 31 repeatedly transfused patients with or without thrombocytopenia and 24 patients with autoimmune disease (SLE andmyasthenia gravis) without thrombocytopenia. The frequency of a positive test was greatest in the patients with ITP (61%), SLE (50%) or a history of numerous blood transfusions (60%). The patients withmyasthenia gravis also showed a considerable frequency (20%) of platelet antibodies detectable by the PF3 test. The PF3 test is less sensitive than the serotonin release test in detecting autoantibodies, but it is more sensitive than aggregometry in detecting isoantibodies and drug-related antibodies.  相似文献   
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