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1.
Records on 1546 children who were identified as having attended schools in Seascale up to November 1984 and were born since 1950 but not in the civil parish were studied. These children lived in or near Seascale for a period of time while they were attending one or more of three local schools and are an additional group to the 1068 children who were identified as born to mothers resident in Seascale in an accompanying study. Even though some of the schoolchildren apparently remained in the village for a short period only all but 7% were followed up through the National Health Service Central Register. Mortality among these children to 30 June 1986 is comparable to that expected at national rates. From all causes there were 10 observed deaths compared with 12.69 expected--a ratio of 0.79 (95% confidence interval 0.38 to 1.45)--and from cancer one observed death compared with 2.04 expected--a ratio of 0.49 (95% CI 0.01 to 2.73). No deaths from leukaemia or lymphoma were reported, but only 0.83 was expected. Since 1971 (the year when cases of cancer were first notified to the NHS Central Register) three non-fatal cases of cancer were reported, including two lymphomas, compared with 2.04 expected and two cases of carcinoma in situ of the cervix compared with 1.79 expected. In addition, there was a case of leukaemia among the schoolchildren which was known previously and had been diagnosed in 1968. There is an interesting difference between the results of this study and the results of the study of children born to mothers who were resident in Seascale. In the latter study there was an excess of leukaemia and of other cancers, but a similar finding is not apparent among children who spent some time at schools in Seascale but were born elsewhere. This raises the question of whether one or more aetiological factors in childhood cancer were acting on a locality specific basis before birth or early in life. This cannot be answered from these cohort studies, but it is hoped that the case-control study that is under way in West Cumbria will provide relevant information.  相似文献   
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OBJECTIVES: To determine the accuracy of self-reported comorbidities compared with medical record review and the clinical and sociodemographic characteristics associated with accuracy of self-reported comorbidities. STUDY DESIGN: We conducted a prospective study of 458 newly diagnosed head and neck cancer patients using self-administered questionnaire and medical chart review data. Overall and itemwise consistency between self-report and chart review was evaluated. Social, clinical, and demographic characteristics of consistent versus inconsistent responders were analyzed. RESULTS: Seventy-four percent of patients had at least one comorbidity. There was good overall consistency between self-report and chart review (kappa = 0.50). Compared with consistent responders, inconsistent responders were found to be older (P < 0.05), have lower sleep (P < 0.05) and physical activity scores (P < 0.05), be more depressed (P < 0.05), and have more severe comorbidities (P < 0.05). CONCLUSIONS AND SIGNIFICANCE: Self-report may be considered as an alternative to chart review for comorbidity assessment in head and neck cancer patients. Younger patients, those with good general health, fewer depressive symptoms, and mild comorbidities, are more likely to give responses consistent with chart review.  相似文献   
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Summary We describe a technique using normal and diabetic (dbdb) mice to establish primary pancreatic cultures that spread and assume a characteristic epithelial morphology. These cultures contain 4 to 7% beta cells, secrete insulin in response to stimuli for 10 to 14 d, contain few fibroblasts, and have a cell viability that is greater than 95%. The cells attach firmly to glass cover slips and are ideal for the study of insulin secretory granules or contractile proteins using indirect immunofluorescence.  相似文献   
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In the sickle cell syndromes, Hb A2 measurements aid in the differential diagnosis of sickle cell anemia from sickle-beta-thalassemia. The purpose of this study is to assess the Hb A2 levels in samples containing sickle hemoglobin (Hb S) by the use of an automated high performance liquid chromatography system (HPLC-Variant beta-thalassemia Short Program). The blood samples analyzed were from individuals of African descent living in the state of Tennessee who had either sickle cell trait (Hb AS), sickle cell disease (Hb SS), or sickle cell-hemoglobin C disease (Hb SC). Interestingly, the Hb A2 levels determined by HPLC were found elevated in samples containing Hb S. The Hb A2 mean in Hb AS samples (n=146) is 4.09% (SD +/- 0.42, range 2.20 to 5.20%); in Hb SS samples (n=33) it is 3.90% (SD +/- 1.08, range 0.60 to 5.90%); and in Hb SC samples (n=27) it is 4.46% (SD +/- 0.70, range 2.30 to 5.91%). The Hb A2 mean by HPLC in normal individuals (Hb AA, n=70) is 2.57% (SD +/- 0.25, range 2.1 to 3.0%), and the Hb A2 range in beta-thalassemia carriers is 4 to 9%. Our results show that the Hb A2 levels in Hb S-containing samples partially overlap with those expected from beta-thalassemia carriers. The hemoglobinopathy laboratory should be aware of this apparent elevation in Hb A2 levels determined by HPLC in individuals carrying Hb S. Other factors, such as family history and clinical symptoms, should be taken into account before a diagnosis of sickle cell trait, sickle-beta-thalassemia, or sickle cell anemia is made.  相似文献   
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BACKGROUND: Nasal polyps are a common problem that is difficult to diagnose and treat, in part because the cause of nasal polyposis is unknown. Although information on the pathogenesis of polyposis is lacking, there are reports suggesting that a genetic predisposition underlies this disorder. OBJECTIVE: We sought to better understand the basis of nasal polyposis associated with allergic rhinitis. We hypothesize that the expression of unique genes is associated with the nasal polyposis phenotype. METHODS: We examined 12000 human genes transcribed in the nasal mucosa of patients with allergic rhinitis with and without nasal polyps. Biopsy specimens of the mucosa of patients with and without polyps were obtained after the patients refrained from the use of topical or systemic steroid therapy for 2 weeks. RESULTS: Thirty-four genes were differentially expressed between the patient groups, including those for inflammatory molecules and putative growth factors. The greatest differential expression identified by the array analysis was for a group of genes associated with neoplasia, including mammaglobin, a gene transcribed 12-fold higher in patients with polyps compared with control patients with rhinitis alone. Quantitative RT-PCR confirmed this differential expression and documented that the number of mammaglobin mRNA copies is actually 64-fold greater in tissues of patients with polyps versus control patients. The specificity of mammaglobin protein expression was evaluated by means of immunohistochemistry, which showed specific staining in nasal polyp mucosal goblet cells only in patients with polyps. CONCLUSION: These data suggest that nasal polyposis involves deregulated cell growth, using gene activation in some ways similar to a neoplasm. In addition, mammaglobin, a gene of unknown function associated with breast neoplasia, might be related to polyp growth.  相似文献   
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2-Mercaptoethanol (2-ME) is widely used in rodent lymphoid cell cultures as an enhancer of multiple cellular functions. We have confirmed that the action of 2-ME must be on a serum component(s), rather than a direct action on the cells. The serum component(s) is contained within the dialyzable fraction of fetal calf serum (FCS) since: (a) dialysis of FCS diminished the ability of FCS to support an antibody response even in the presence of 2-ME; and (b) FCS dialysate, pulsed with 2-ME, restored the ability of dialyzed FCS to support an antibody response. Diminution of the reduced glutathione content of FCS by heating reduced the capacity of FCS to support an antibody response, whereas addition of 2-ME-pulsed glutathione restored the supportive capacity of heated FCS. Conversely, oxidized glutathione inhibited the antibody response in the absence of 2-ME, but that inhibition was not seen in the presence of 2-ME. We have concluded that reduced glutathione is an essential component in FCS in order for 2-ME to produce its enhancing effect. The most plausible explanation for the enhancement of antibody responses, in vitro, by 2-ME is the concomitant reversal of the inhibitory effect of oxidized glutathione and the increased availability of reduced glutathione which can scavenge oxygen-derived radicals, thus protecting macrophages and lymphocytes from the deleterious effects of oxygen-derived free radicals.  相似文献   
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In this study we assessed the impact of administrative changes occurring in 1993 on the Indiana Children's Special Health Care Services program. Responses from a 1994-1995 survey were compared with a 199 1 survey. Unmet needs declined in 6 categories: primary medical care, hospital services, home nursing care, physical therapy, occupational therapy, and special equipment. Unmet needs remained the same in 6 categories: specialty care, speech therapy, respite care, parent support, child support, and sibling support. Unmet needs increased in 5 categories: dental care, mental health, transportation, housing modifications, and child and day care. Although program changes improved the health care needs of clients in many areas, additional efforts are still needed.  相似文献   
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Twenty-seven pesticide workers with elevated blood levels of dieldrin (15 ppb) were involved in a case-control study which included history and physical examination, comprehensive neurological evaluation, laboratory tests, and psychological and psychomotor testing. No clinically important differences were found on history, physical, specialized neurological tests, or laboratory examination. The exposed group showed a statistically significant difference in five out of 58 psychological (P) and psychomotor (PM) tests—at least three would be expected by chance (p .05). In only one of these tests was there any significant correlation with dieldrin levels. Even though the exposed group had worse scores than the control group in 47 of 58 P-PM tests, such scores were, with a few exceptions, in the normal range of values. Elevated blood levels of dieldrin encountered in this study do not appear to have any chronic deleterious effects on health, as measured by conventional medical work-up and extensive central nervous system testing.  相似文献   
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