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BACKGROUND: Borrelia burgdorferi, the causative agent of Lyme disease, has never been isolated from a patient thought to have acquired Lyme disease in any southeastern state. OBJECTIVE: To investigate 14 cases of an erythema migrans (EM)-like rash illness that occurred during 2 summers at an outdoor camp in central North Carolina in an effort to determine the etiologic, epidemiological, and clinical aspects of this illness. METHODS: Using active surveillance, we identified cases of clinically diagnosed EM in residents and staff of the camp. We collected clinical and demographic information; history of exposure to ticks; acute and convalescent serum antibodies to B. burgdorferi, Rickettsia rickettsii, and Ehrlichia chaffeensis; and cultures for spirochetes from biopsy specimens of skin lesions. Serum samples from a group of residents and staff who did not develop rashes were tested for the same antibodies. We speciated ticks removed from people and collected from vegetation. RESULTS: We identified 14 cases of EM-like rash illness during the 2 summers. Of the 14 case-patients, 10 had associated mild systemic symptoms and 1 had documented fever. All 14 case-patients had removed attached ticks, and 8 remembered having removed a tick from the site where the rash developed a median of 12 days earlier (range, 2-21 days). One tick removed from the site where a rash later developed was identified as Amblyomma americanum, the Lone Star tick; 97% of ticks collected from vegetation and 95% of ticks removed from people were A. americanum. No spirochetes were isolated from skin biopsy specimens. Paired serum samples from 13 case-patients did not show diagnostic antibody responses to B. burgdorferi or other tick-borne pathogens. CONCLUSIONS: This investigation suggests the existence of a new tick-associated rash illness. We suspect that the disease agent is carried by A. americanum ticks. In the southern United States, EM-like rash illness should no longer be considered definitive evidence of early Lyme disease.  相似文献   
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A multiple case study design was used to explore the practice of health education in acute care settings in Hong Kong. Two case studies, a medical ward and a surgical ward, were selected to reflect the real setting in which nurses carry out health education in acute care. Data collection methods involved the use of non-participant observation and semi-structured interviews. Seven nurses and eight patients were interviewed to explore their understanding of health education concepts, the use made in the wards of health education and the factors influencing such practice in the acute settings. Individual and cross-case analysis showed that respondents' understanding of the concept of health education was limited to patient information-giving. Although the importance of health education in acute patient care was acknowledged, the degree to which health education featured in nurses' practice was minimal. Many available opportunities for health education were missed and factors such as nurses' busy-ness and the associated lack of time and staff were identified as influencing health education practice in these acute care settings. Implications for practice and future studies were discussed in the light of these findings.  相似文献   
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To aid treatment choice in early stage of Hodgkin's disease, we analysed patients registered in the IDHD Database with clinical stages I or II Hodgkin's disease who were not staged with laparotomy and whose initial treatment was with radiotherapy alone. The factors analysed for outcome after first relapse included initial stage, age, sex, histology, number of involved areas, mediastinal involvement, E-lesions, B-symptoms, erythrocyte sedimentation rate, alkaline phosphatase, serum albumin and haemoglobin. As well as presentation variables, we analysed the disease-free interval after initial radiotherapy and the extent of disease at relapse. A total of 1364 patients with clinical stage I or II Hodgkin's disease were treated with initial radiotherapy, of whom 473 relapsed. The probability of survival 10 years after relapse was 63%. For cause-specific survival (CSS), both multivariate and univariate analysis identified the importance of age at presentation and histological subtypes. When all causes of death were considered, the multivariate analysis identified age as the only significant factor. The length of initial disease-free interval had no influence on prognosis after relapse, but the 169 patients with nodal relapse had a higher cause-specific survival than those with an extranodal component of relapse (74% versus 51% at 10 years, P < 0.005). Thus, the important factors for outcome after initial treatment with radiotherapy are those factors predicting the risk of relapse after initial treatment together with those predicting outcome after relapse, namely age, histologic subtype and extent of disease at relapse.  相似文献   
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1. The present study investigated the effects of peptide T on mean arterial blood pressure (MAP) in conscious normotensive Sprague-Dawley (SD) rats, spontaneously hypertensive rats (SHR) and two-kidney one-clip (2K1C) hypertensive rats. 2. Peptide T was infused via the left jugular vein at a rate of 1 mg/kg per h in SD, SHR and 2K1C rats and then at doses of 0.1, 0.25, 0.5, 1 and 5 mg/kg per h in SHR, with 0.9% saline as a sham control in SHR and 2K1C. Mean arterial pressure was measured directly before, during and after infusion. 3. Peptide T (1 mg/kg per h) decreased blood pressure in both SHR (P < 0.01) and 2K1C (P < 0.05). In normotensive SD rats the fall in MAP approached statistical significance (P = 0.06). The effect of peptide T was not significantly different in normotensive compared with hypertensive rats. Saline infusion had no effect. The blood pressure lowering effect of peptide T appeared to be dose-dependent in SHR.  相似文献   
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Intraepidermal neutrophilic IgA dermatosis, a rare skin disease entity manifested with blisters and pustules clinically and lower epidermal blister, acantholysis, and neutrophilic infiltration pathologically, was first reported in 1985. Although the disease is characterized by IgA autoantibodies targeting the epithelial cell surface component, the target antigen has not been determined. We investigated a patient with this disease by histopathology, direct and indirect immunofluorescence, immunoblotting, and immunoadsorption studies. The pustular lesion was characterized by blister at the lower epidermis, acantholysis, and neutrophilic infiltration. Nonsecretory IgA1 subclass autoantibodies targeting the lower epithelial cell surfaces were detected in the patient's skin and serum. The patient's IgA autoantibodies labeled a recombinant desmosomal protein desmoglein 3 on immunoblotting and the immunolabeling of epithelial cell surfaces was eliminated by preadsorption with desmoglein 3. Thus, desmoglein 3 is identified as a target antigen in intraepidermal neutrophilic IgA dermatosis. The ability of IgA1 autoantibodies to bind neutrophils may be responsible for the prominent neutrophilic infiltration observed histopathologically and for the pustular lesions observed clinically.  相似文献   
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AIDS-related malignancies (ARM) include AIDS-defining cancers such as Kaposi's sarcoma, non-Hodgkin's lymphoma and cervical carcinoma. In addition, certain other malignancies are also increased with human immunodeficiency virus (HIV) infection. New antiretroviral agents and better prophylaxis and treatment of HIV-related opportunistic infections are prolonging the lives of HIV-infected individuals. There will thus likely be a continued rise in the incidence and prevalence of ARM in the long term, even if effective antiretroviral and other AIDS-related therapies reduce their appearance in the short term. There are presently no curative regimens for the common ARM, with the possible exception of some lymphomas. Survival is shortened by most, and treatment is often toxic and poorly tolerated. Gene therapies may thus offer a useful adjunct to conventional treatment strategies for selected ARM. Although some gene therapy strategies may work well in the HIV setting, the chronic viral infection, immunodeficient status of the host, the tendency for HIV-infected individuals to have altered drug metabolism and an increased rate of adverse drug reactions will likely present special challenges. This review summarizes the state-of-the-art in the fledgling field of gene therapy for ARM, and explores areas for future research.  相似文献   
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