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41.
Treatment results among adults with childhood tumors: a 20-year experience   总被引:1,自引:0,他引:1  
Controversy exists regarding the most appropriate treatment for the rare adult patient who develops a so-called pediatric cancer. We have reviewed our 20-year experience with these patients and analyzed their outcome. A total of 299 patients with rhabdomyosarcoma (106), Wilms' tumor (97), and neuroblastoma (96) were evaluated and treated at Stanford University Medical Center between January 1967 and December 1987. Only 26 of these patients (8.7%) were diagnosed during "adulthood"; their age range was 18-67 years, median 23 years. Wilms' tumor; Five patients presented with Wilms' tumor at age greater than or equal to 18 years; four had unfavorable histology. All underwent multimodality therapy; however, only two have survived, one currently disease-free and one with disease. Neuroblastoma: Five patients presented with neuroblastoma at age greater than or equal to 18 years. Four underwent attempted surgical resection, post-operative irradiation (RT), and chemotherapy (CT); the other received no adjuvant CT. Only two of the five patients survive, both with disease. Rhabdomyosarcoma: Of the 16 adults (greater than or equal to 21 years) with rhabdomyosarcoma, 14 (87%) had advanced Intergroup Rhabdomyosarcoma Study-group disease (eight Group III, six Group IV). All 16 underwent aggressive multimodality therapy. At 10 months-16 years follow-up, only five patients survive, four of whom are apparently cured of their tumor. Neither histologic subtype nor site of presentation were of prognostic value. This series demonstrates that adults with Wilms' tumor, neuroblastoma, or rhabdomyosarcoma have a worse prognosis than do children with the same diagnosis. Possible explanations for this disparity in outcome include different tumor biology, less tolerance for treatment, and different natural history among adults relative to children.  相似文献   
42.
Inflammatory bowel disease (IBD) is a group of chronic inflammatory diseases of the gastrointestinal tract of unknown aetiology. Evidence of abnormalities in immune regulation and cytokine production in patients with IBD has led to investigations of various immuno-regulatory genes as potential candidate susceptibility loci. Studies using whole genome scanning have highlighted chromosomes 3, 7, 12 and 16. A 32 base-pair deletion in the CC-chemokine receptor-5 gene (CCR5-A32, chromosome 3p21.3) has been associated with susceptibility to IBD. We have investigated CCR5 as a candidate susceptibility gene in 350 patients (251 with ulcerative colitis and 99 with Crohn's disease) and 103 controls using polymerase chain reaction. There were no significant differences in the distribution of CCR5 genotypes or frequencies comparing patients and controls, or associations with extent of colitis. In contrast to preliminary data, these findings suggest no evidence for involvement of this mutation in susceptibility/resistance or disease progression in IBD.  相似文献   
43.
The aim of this study was to assess the prevalence of hearing loss among people aged 65 years and over and to offer hearing aids where necessary. The study was carried out in a large health centre practice in Birmingham with a computerized record system. All patients aged 65 years, and a 20% random sample of patients aged 66 years and over were invited for interview. They were questioned about hearing loss and examined audiometrically. All patients with a hearing loss in the better ear of 35 decibels or more over the speech frequencies (0.5-4 kHz) were offered a hearing aid. A total of 322 patients attended (72% of those invited) and of these 34 patients already had a hearing aid. A further 142 patients were identified for whom an aid was recommended and 69 of these accepted. The acceptance rate was higher among men than women (57% compared with 43%). Sixty one patients (19% of those screened) had an asymmetrical hearing loss and of these 24 required consultant assessment; none had serious underlying pathology. There is a large unmet need for hearing aid provision. Simple audiometric assessment in health centres provides an opportunity to meet this need.  相似文献   
44.
45.
Summary Persistent foot-and-mouth disease (FMD) virus infection in vitro has been studied in a chronically infected cloned BHK-21 cell line. Virus growth during serial cell passages was followed by infectivity assay and immunocytochemical staining. Only a small percentage of cells (0.006–6%) was found to harbour virus during persistence. Light and electron microscopy showed the presence of cytoplasmic protuberances (blebs) at the surface of persistently infected cells. The curing of cell cultures was achieved by passaging them in the presence of polyvalent immune serum. The absence of virus in cured cells was confirmed by infectivity assay and immunocytochemistry. This finding, together with the low percentage of infected cells in cultures confirms that persistently infected BHK-21 cells satisfy the definitions of a carrier culture. The characteristics of the in vitro system and its relevance to the study of FMD carrier state in vivo are discussed.  相似文献   
46.
Quartz deposition in the rat lung causes an intense and persistent neutrophil alveolitis leading to parenchymal fibrosis. Bronchoalveolar leucocytes (BAL) from quartz-exposed rat lungs were studied for their effects on splenic lymphocyte proliferation; titanium dioxide (TiO2) was used as a control, non-fibrogenic dust. Seven days after the intratracheal instillation of 1 mg of quartz or TiO2 suspended in phosphate-buffered saline (PBS), BAL were recovered by lavage; the effect of PBS alone was also studied. TiO2-elicited BAL (macrophages greater than 98%) inhibited splenocytes responding to suboptimal phytohaemagglutinin (PHA) more than PBS-elicited BAL (macrophages greater than 98%); the effect was dependent on the BAL:splenic lymphocyte ratio. Quartz-elicited whole BAL (macrophages 49%, neutrophils 51%), and an alveolar macrophage-enriched population with purity of 87% separated from it, were less inhibitory to splenocyte mitogenesis than PBS-elicited BAL. A neutrophil-enriched population, with a purity of 80%, markedly enhanced splenocyte response to PHA. In addition, whole quartz BAL and the macrophage-enriched population obtained from it enhanced the mitogenesis of T cell-enriched lymphocytes at a much lower BAL:lymphocyte ratio. The neutrophil-enriched quartz BAL enhanced mitogenesis substantially more than the whole or macrophage-enriched population from quartz-exposed lung. Supernatants from normal macrophages, PBS BAL, TiO2 BAL, quartz BAL and both alveolar macrophage and neutrophil-enriched quartz populations were assessed for interleukin-1 (IL-1) activity. Quartz-BAL, quartz macrophages and quartz neutrophils all produced significantly higher IL-1 levels than PBS BAL; the supernatants from quartz neutrophils, however, showed the highest IL-1 activity. These findings suggest that quartz-elicited bronchoalveolar leukocytes, especially neutrophils, enhance lymphocyte proliferation and that increased IL-1 secretion by these cells is likely to be the effector molecule involved. These findings have important implications for immune response in mineral dust-stimulated lung and for inflammatory lung disease in general.  相似文献   
47.
Formation of N-nitroso compounds in gastric juice has been implicated in the pathogenesis of cancer in the stomach after operation. Gastric juice was aspirated from 85 subjects: 23 were controls, 51 had previously undergone vagotomy and gastrojejunostomy, and 11 had previously undergone vagotomy and pyloroplasty. The gastric juice samples were analysed for pH, nitrite, and total N-nitroso compounds. A significant correlation was found between pH and nitrite concentration (p less than 0.01). No significant correlation was found between pH and total N-nitroso compound concentration or between nitrite and N-nitroso compound concentration. The vagotomy and gastrojejunostomy patients had higher pH values and higher concentrations of nitrites and N-nitroso compounds than controls (p = 0.01 in all cases). The 51 vagotomy and gastrojejunostomy patients also underwent endoscopy and biopsy. They were divided into three groups: group 1 (21 patients) had no intestinal metaplasia and no more than mild dysplasia; group 2 (20 patients) had intestinal metaplasia; and group 3 (10 patients) had moderate or severe dysplasia. Groups 2 and 3 both had higher pH values and higher nitrite concentrations than group 1 (p = 0.01 in all cases). There was no significant difference, however, between either group 2 or 3 and group 1 for total N-nitroso compound concentration. Since there was no simple linear relation between pH and N-nitroso compound concentration, it was concluded that formation of N-nitroso compounds at high pH was unlikely to be involved in the pathogenesis of gastric cancer in the hypochlorhydric stomach after operation. The relation between nitrite and histological abnormality was not associated with a similar relation between N-nitroso compounds and histological abnormality. It therefore appears that there is no simple relation between N-nitroso compounds and the pathogenesis of premalignant gastric mucosal changes.  相似文献   
48.
The paper introduces the electrode limit-voltage plane (ELVP)—a useful tool for describing in electrical terms what a polarisable electrode is doing under a particular set of conditions. The ELVP is then used to consider the charge-injection capability of a platinum stimulating electrode.  相似文献   
49.
Erythrocyte survival has been studied in a strain of mice which develop autoimmune haemolytic anaemia in adult life (NZB/B1), and also in CBA and C57B1 mice, using one or both of two radioactive isotope labels, 51Cr and 32P.

Erythrocyte survival is customarily expressed as the half-life but this is unsatisfactory for purposes of statistical comparison and we have used instead a parameter `κ' which represents the slope of the line obtained when: log(Counts per unit haemoglobin on day t)/(Counts per unit haemoglobin on day 0) is plotted against time.

Young NZB/B1 mice yield values of κ intermediate between those obtained in CBA and C57B1 mice, and may reasonably be judged to show normal erythrocyte survival. On the other hand, in older NZB/B1 mice which are strongly Coombs positive and show reticulocytosis and anaemia, erythrocyte survival is greatly shortened.

The survival of erythrocytes transfused to NZB/B1 recipients from isogeneic donors was found to be similar to that of the recipient's own erythrocytes, irrespective of whether or not the donor was Coombs positive or showed other evidence of haemolytic activity.

The values of κ obtained in NZB/B1 mice were essentially the same with both labels; in CBA mice, however, a significant difference was observed.

  相似文献   
50.
In mid-1988 a postal survey was conducted of one in five general practitioners in England and Wales, to examine their contact with people with human immunodeficiency virus (HIV) infection, with the acquired immune deficiency syndrome (AIDS) or with worries about HIV infection or AIDS. The response rate was 63.9%. Of the 3339 respondents 22.7% knew of an asymptomatic HIV positive patient within their practice, 5.4% knew of a symptomatic HIV positive patient and 6.4% knew of a patient with AIDS. The estimated annual rate for HIV-related consultations in general practice (including consultations with the 'worried well') was 6.5 per 1000 population. HIV-related consultations occurred more frequently in the four Thames health regions than elsewhere. A sample of 715 practitioners who reported consultations with HIV infected people or those with worries about infection in the previous month, were invited to keep a diary of HIV-related consultations for one week. The response rate to the diary was 64%. Nineteen per cent of the 273 consultations recorded in the diaries were initiated by homosexual men, 16.5% by injecting drug users, 10.3% by the sexual partners of people at risk of infection; 42.9% of consultations were not associated with recognized risk factors. The results indicate that general practitioners have substantial contact with patients with HIV infection, with AIDS and with worries about HIV infection or AIDS. This contact is likely to increase, alongside the anticipated spread of HIV infection, with consequent implications for general practice resources.  相似文献   
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