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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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FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
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Development of a new wound dressing with antimicrobial delivery capability   总被引:1,自引:0,他引:1  
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.  相似文献   
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The use of self-expanding prostheses in the management of malignant oesophageal strictures has become well established. The majority of benign peptic oesophageal strictures can be successfully managed using endoscopic or fluoroscopically guided balloon oesophageal dilatation combined with long-term drug therapy, particularly using proton pumper inhibitors. Although endoscopic oesophageal dilatation can be performed on an outpatient basis, it requires repeated hospital visits. There is a small risk of oesophageal perforation whilst cardio-respiratory complications may be encountered during the use of intravenous sedation in an elderly population. The use of a self-expanding Strecker stent in a 98 year old woman with a benign oesophageal stricture is described.  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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