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The cellular infiltrate present in human diseased gingiva was analyzed in biopsies from 12 patients with gingivitis or periodontitis. The samples studied had been obtained in the course of surgery at inflammatory sites remaining after institution of periodontal treatment. Histological and immunological techniques were used to identify macrophages, B-cells, plasma-cells, T-cells and T cell subsets, as well as cells expressing class II HLA membrane antigens. T-cells appeared as the predominant population, but plasma-cells were also visualized in nearly all samples. Both OKT4+ and OKT8+ cells were seen in all cases, the latter being more numerous in periodontitis patients. Interdigitating-like cells were observed, positively labelled for class II antigens, as well as macrophages which were more numerous in periodontitis patients. These results suggest the participation of all components of the immune response in gingival disease, in a way resembling chronic recurrent inflammatory diseases.  相似文献   
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There is evidence that leukocyte contaminating red blood cells and platelet concentrates are responsible for refractoriness to platelet transfusions. The efficacy of a cotton-wool filter to remove leukocytes from red blood cells has been documented previously. The present study was designed to evaluate whether the cotton-wool filters can effectively remove leukocytes from platelet concentrates. Sixty pools of random-donor platelets and single-donor plateletpheresis products were filtered through a cotton-wool filter. The efficacy of filtration was determined by measuring the absolute numbers of leukocytes and platelets and subpopulations of mononuclear cells. The average platelet loss was 8% per pool of random platelets and 10% per plateletpheresis product. The average leukocyte removal was 99% from a pool of random platelets and plateletpheresis concentrates collected by CS-3000 and 90% from plateletpheresis concentrates harvested by single-stage COBE/IBM-2997. The filtration removed 100% of granulocytes, 95% of monocytes, 90% of B-lymphocytes, and 85% of T-lymphocytes. We conclude that filtration through a cotton-wool filter is an efficient and cost-effective method for preparation of leukocyte-poor platelets.  相似文献   
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The consequences of alcoholism on the mental health of spouses of lifetime at-risk drinkers are only known from studies on alcoholics already in treatment. A retrospective analysis was conducted using data from a Quebec community health survey. The purpose of this study was twofold. First, our goal was to ascertain the mental health of female spouses living with a male lifetime at-risk drinker. Secondly, we wanted to examine the relationship between male lifetime at-risk drinkers (aged 30-54 years) and the psychological distress of their nondrinking female spouses. Lifetime at-risk drinking, for the purposes of this study, was defined as having at least two positive answers to the CAGE questionnaire. Couples wherein both spouses were deemed not at-risk for problem drinking by the CAGE instrument (0 or 1 positive answer) formed the control group. Psychological distress was measured using the Indice de Détresse Psychologique de l'Enquête Santé Québec (Préville, M., Boyer, R., Potvin, L., Perreault, C., & Légaré, G. (1992). La détresse psychologique: détermination de la fiabilité et de la validité de la mesure utilisée dans l'enquête Santé Québec. Cahier de recherches #7, Montréal, Santé Québec.). It measures symptoms of anxiety, depression, aggressivity, and cognitive impairments. Scores of >or=22 (out of 100) were indicative of a high level of psychological distress. This study confirmed higher levels of psychological distress in female spouses of male lifetime at-risk drinkers in the general population. An exploratory study examined the association between the psychological distress of female spouses and each of the following nine independent variables: male partner lifetime at-risk drinker, stressful life events, job situation, socioeconomic status, perceived health status, presence of children less than 15 years, length of the marital relationship, presence of a confidant, and availability of social support. Lifetime at-risk drinking is a risk factor for the spouse's psychological distress. An examination of the demographic characteristics related to alcohol intake in male lifetime at-risk drinkers is also described in this study.  相似文献   
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PURPOSE: To analyze the effectiveness of surgery and chemotherapy with or without radiotherapy in the management of limited small cell lung cancer (LSCLC) in stages I and II. PATIENTS AND METHODS: 39 patients (median age 62 years) with LSCLC in stages pT1 or pT2 and pN0 or pN1 (stages IA-IIB) who had a tumor resection and systematic lymph node dissection were reviewed retrospectively. The median follow-up period was 29 months. 35 patients (90%) received a median of four cycles of a platinum-containing chemotherapy postoperatively. 16 patients (41%) received an adjuvant thoracic radiotherapy (TRT, median 50 Gy); 21 patients (54%) received a prophylactic cranial irradiation (PCI, median 30 Gy). RESULTS: The median overall survival for all patients was 47 months, resulting in actuarial 1-, 3-, and 5-year survival rates of 97%, 58%, and 49%, respectively. Distant metastases were found in 13 patients (33%) after a median of 16 months. Patients who received an adjuvant TRT showed a trend toward improved thoracic recurrence-free survival (p = 0.06) and improved overall survival (p = 0.07) compared to those treated with surgery and chemotherapy only. Brain metastasis-free survival (p = 0.01) and overall survival (p = 0.01) were improved significantly in patients who received a PCI. CONCLUSION: Surgical tumor resection may be considered for carefully selected patients. Adjuvant chemotherapy and PCI are recommended for all patients. Adjuvant TRT is currently used in patients with positive lymph nodes (pN1), because the probability of a subclinical involvement of the mediastinal lymphatic system appears to be increased in these patients.  相似文献   
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