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A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection.  相似文献   
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地点:2002-2003年,在华盛顿King县,结核病(TB)在多个收容所的人群中大规模爆发。 目的:控制结核病在多个地点的传播。设计:2002年,对收容所病人的接触者进行筛查,作结核菌素皮试(TSTs)和症状回顾。根据这些筛查的结果,确定和优选传播的地点。2003年,对暴露于这些点的队列作彻底的筛查(例如,症状回顾,TST,胸部X线检查[CXR],痰检和痰培养)。利用PCR为基础的方法对从病人那里分离出来的结核分枝杆菌作基因分型,以快速确认爆发相关病人。 结果:2002-2003年,King县313例确诊的病人中有48例(15%)与爆发相关;通过基因分型,47例培阳病人分离出和爆发相匹配的菌株。3个收容所由于在2002年接纳的病人超过12人,所以人群中TST阳性率(约30%)高于收容所中的一般水平(7%)。用一个痰培养筛查接触者和CXR发现结核病人的敏感度相似(分别为77%和62%)。 结论:一个广泛的资源密集的途径可能有助于控制疾病的传播。这次爆发突显出无家可归者的脆弱性和在城市维持强有力的结核病规划的必要性。  相似文献   
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Trends in the incidence of histologically diagnosed dysplastic lesions of the intra-oral mucosa have been investigated for the period 1975-89 in a well defined population of 1.5 million. These have been contrasted and compared with trends in the incidence of intra-oral carcinoma. Cases were ascertained from the records of all the histopathology laboratories that serve the Northern Ireland population. Over the 15-year period, there were 135 cases of histologically diagnosed epithelial dysplasia. In contrast to the significant increase in the incidence of intra-oral carcinoma, there was no significant change in the annual age standardised incidence of dysplastic lesions over the period. The ratio of malignant to dysplastic diagnoses rose from 2.5:1 to 5.4:1. Only 24 of the dysplastic lesions were known to have subsequently progressed to malignant carcinoma, representing 4.5% of all invasive tumours diagnosed during 1975-89. The results highlight a number of unresolved issues regarding the natural history of intra-oral carcinoma.  相似文献   
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Site-directed antisera generated by peptide immunization have been used to study the antigenicity of bovine growth hormone (bGH). Prediction of sequential antigenic sites has been performed using secondary structure information derived from the 'Protean' prediction routine. The structures predicted by this programme agree closely with the corresponding structure of GH recently derived from crystallographic studies. We have previously shown that the binding of monoclonal antibodies of particular epitope specificity to human or bovine GH results in significant enhancement of hormonal activity in vivo; however, the sites recognized by these antibodies were not known. Here we identify a sequence region, corresponding to a loop structure joining helices 3 and 4, which, is associated with the growth enhancement phenomenon. Antisera raised to either of two overlapping peptides (residues 120-140 and 134-154) significantly increase the biological activity of GH in vivo. Antisera directed to other regions on the GH molecule failed to demonstrate this property. Coincidentally, the sites recognized by the growth-enhancing anti-peptide antisera overlap with the site on GH which is highly susceptible to proteolytic cleavage; such cleavage has been shown in some cases to result in hormone enhancement.  相似文献   
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OBJECTIVES: To investigate the activities which may exacerbate symptoms in patients with varicose veins. METHODS: Questionnaires sent to patients before clinics and at least six months later. RESULTS: Both questionnaires were returned by 149 of 203 patients (74%) but only 124 contained adequate data for comparison--55 from patients who had surgical treatment and 69 who had no surgery. At initial presentation, worsening of discomfort attributed to varicose veins was common during (58%) or after (48%) standing and in hot weather (44%), but less when sitting with the feet down (31%), and after (31%) or when walking (19%). Surgery significantly reduced the total number of symptoms reported by patients at follow-up (p<0.02). However, none of the symptoms reported during specific activities was significantly lessened by surgery compared with no treatment--possibly because the attrition of patients during the study resulted in small numbers for analysis. CONCLUSIONS: Symptoms are a common indication for treating varicose veins and it is therefore important to be sure that they are due to the veins, rather than other causes. This report highlights traditional and logical questions which may help to identify symptoms caused by varicose veins but illustrates the difficulty of validating them.  相似文献   
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G Hulks  M D Cowan    J W Kerr 《Thorax》1990,45(8):635-636
Right sided intrathoracic kidney associated with ipsilateral pulmonary hypoplasia and Bochdalek hernia in a 13 year old girl was diagnosed by computed tomography.  相似文献   
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Features of 111 mammary carcinomas derived from breast cancer screening were compared with those of 69 carcinomas presenting 'clinically'. Screen detected cancers were smaller, had less likelihood of nodal metastases, included a higher proportion of in situ tumours and if invasive, tended to be of lower grade. Using immunohistochemical methods, the expression of c-erbB-2 oncoprotein, epidermal growth factor receptor (EGFR) and cathepsin D were compared in the two groups. A similar proportion of screened and unscreened tumours expressed c-erbB-2 oncoprotein and EGFR but expression of the oestrogen regulated protein cathepsin D was significantly more frequent in the screened group (P less than 0.05). Although a relatively small series, the results suggest a biological difference between 'screened' and 'clinical' tumours.  相似文献   
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