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11.
Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated.  相似文献   
12.

Background  

Some studies have found that lower parity and higher or lower social class (depending on the study) are associated with increased risks of childhood acute lymphoblastic leukaemia (ALL). Such findings have led to suggestions that infection could play a role in the causation of this disease. An earlier New Zealand study found a protective effect of parental marriage on the risk of childhood ALL, and studies elsewhere have reported increased risks in relation to older parental ages. This study aimed to assess whether lower parity, lower social class, unmarried status and older parental ages increase the risk of childhood ALL (primarily). These variables were also assessed in relation to the risks of childhood acute non-lymphoblastic leukaemia, non-Hodgkin's lymphomas and Hodgkin's disease.  相似文献   
13.
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers.  相似文献   
14.
Surface-active phospholipid as the lubricating component of lubricin   总被引:5,自引:0,他引:5  
To resolve the apparent conflict between a lubricating glycoprotein, 'lubricin', as the active ingredient in synovial fluid (SF) and surface- active phospholipid (SAPL) present in SF (and adsorbed to articular cartilage) as the boundary lubricant reducing friction to such low physiological levels, lubricin was isolated from bovine SF following the original procedure of Swann et al. (Arthritis Rheum 1981;24:22-30). Analysis of the lipid extract by thin-layer chromatography and phosphorus determination demonstrated a phospholipid component of 11.1 +/- 1.7% (N = 5) which corresponds very closely to the 9.2-13.0% of lubricin which had hitherto remained unidentified and which has previously been shown to be transferable to the articular surface to impart lubrication. These results would appear to resolve any theoretical conflict in that lubricin is, indeed, an active ingredient within SF. Yet, as a large water-soluble molecule, it really functions as a carrier for the highly insoluble SAPL which it deposits on the articular surface as the oligolamellar layer visualized in previous studies. However, it is this deposited SAPL, rather than lubricin, which actually lubricates.   相似文献   
15.
目的分析影响大学生饮酒模式的因素,针对饮酒教育及酒精政策提出建议。方法采用整群抽样方法,选择来自北京和郑州的530名大学生完成有效问卷调查。采用 Epidata 录入数据,SAS 12.0和 R 2.7.2进行数据描述和分析。结果74.5%的大学生在过去1年内饮过酒,啤酒是饮酒者的主要选择(85.9%),餐馆和家里是饮酒比较频繁的场所,饮用酒多来自同学/朋友及家庭成员提供,25.3%饮酒者并无特别原因饮酒,各有约1/5的饮酒者是出于社交目的或喜欢饮酒的感觉。认为“饮酒有助于社交暠或“饮酒促进交流暠者、父母及同学/朋友饮酒者、来自农村地区或小城镇者及吸烟者更容易发生饮酒行为(均 P 〈0.05),男生大学生、规律饮酒者更容易遭遇强迫劝酒场面、更易发生醉酒(均 P 〈0.05)。超过一半饮酒者出现酒后脸红、肌肉软弱无力等生理反应,饮酒对被调查大学生产生的社会心理影响依次是记忆丧失(23.9%)、宿醉(14.6%)、做了后悔的事(低于10%)等。结论目前大学生仍保持着一种低风险饮酒模式。大学生饮酒教育应提供关于饮酒利弊的科学信息,使其对饮酒保持一种现实的期望。应制定针对性酒精政策和教育鼓励和支持低风险且满足社交功能的饮酒模式,控制高风险饮酒模式。  相似文献   
16.
The frequency of reversible and irreversible visual impairment was determined in children with severe and profound sensorineural deafness, as subnormal vision can adversely affect their educational and social development. Eighty three of 87 such children attending an audiology service were examined to assess the incidence and severity of visual impairment. Each child underwent a detailed ophthalmic assessment. The criteria for visual impairment were visual acuity < 6/9 Snellen or equivalent and/or abnormal binocular vision. Forty five had a normal ophthalmic examination (54.2%). Twenty nine had visual impairment (34.9%) and nine had ophthalmological abnormalities that did not interfere with vision (10.9%). A higher proportion of children with risk factors for visual pathology demonstrated visual impairment than those in whom there were no risk factors. None the less, 44% of visual impairment was among patients without risk factors. The results underline the need to examine all children with severe and profound sensorineural deafness soon after diagnosis and indicate that children with multiple handicaps have a greater likelihood of visual impairment (11 of 14 cases).  相似文献   
17.
18.
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.  相似文献   
19.
PURPOSE: Incidence data for severe aplastic anaemia (SAA) in children are scanty and vary. Few population based studies have been reported. A retrospective and prospective study was conducted to determine the incidence and course of SAA. PATIENTS AND METHODS: All children with a diagnosis of SAA in the Nordic countries from 1982 through 1993 were registered and have been followed up since 1987. RESULTS: A total of 101 children were diagnosed with SAA. The mean annual child population was 4.31 million. A constant incidence of 1.95/million children/year was found: 2.4 for boys and 1.5 for girls. A non-significant increase of cases occurred from November to March. Possible aetiological agents were noted in 29%. The actuarial survival was 79% after one year and 68% after five years without significant difference between boys and girls. CONCLUSION: The incidence of SAA in the Nordic countries remains stable with a preponderance among boys. SAA has still a high initial mortality and a risk of late deaths.  相似文献   
20.
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