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1.
Malignancy of the upper aerodigestive tract is not always associated with obvious localizing symptoms. Presentation may then only be prompted by the appearance of a hard mass in the neck, a metastasis to a cervical lymph node. Neck exploration without a prior diligent search for an occult head and neck primary tumour is to be avoided as it compromises subsequent treatment. The diagnostic investigation of 112 patients complaining solely of a painless and enlarging neck swelling is reviewed. An otolaryngologic examination identified an asymptomatic malignancy of the head and neck in 72 patients (64%). Excision biopsy of the neck mass was required to achieve a diagnosis in only 29 (29%) of those patients who had not already undergone surgery. These results are presented to emphasize the need for a specialist examination of the head and neck prior to embarking on excision of any suspicious neck mass.  相似文献   
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Two recently published multicentre trials have confirmed the overall benefit of carotid endarterectomy in symptomatic patients with severe carotid artery disease. The key to improving further the long-term advantages of carotid endarterectomy, however, remains the continued reduction of the initial operative risk. While the principal responsibility for this continues to be borne by the surgeon, specifically in reducing technical error, the time is perhaps approaching when he or she might also be able to apply some of the recent advances in cerebrovascular research to reduce operative morbidity still further in the future. This article summarizes the aetiology and pathophysiology of operation-related neurological deficits and reviews current approaches towards intraoperative monitoring, cerebral protection and assessment of quality control.  相似文献   
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The aim of this study was to determine the variability of measurements of ankle and brachial systolic pressures and ankle brachial ratios in order to assess their suitability for use in epidemiological studies of arterial disease in the lower limbs. Thirty-six subjects had repeat measurements taken by four observers on two separate days using a Doppler probe and random zero sphygmomanometer. The variability in the measurement of ankle systolic pressure was comparable to that for brachial systolic pressure. The 95% confidence limits of one measurement of the ankle brachial ratio was estimated to be +/- 16%, reducing to +/- 10% for the mean of four measurements taken by two observers on two days. Analysis of variance indicated that the variability in the measurement of ankle brachial ratios attributable to observers, days, timing of measurements on the same day, and repeat measurements was considerably less than the "biological" variability between subjects and between legs. These results suggest that repeatability of the ankle brachial ratio is such that a single measurement is suitable for most epidemiological studies of atherosclerotic peripheral arterial disease.  相似文献   
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The dust content and composition of lesions and hilar lymph nodes from the lungs of British coalworkers have been examined. Samples of macules, fibrotic nodules, and massive fibrosis (both peripheral and central sites) were dissected from 49 lungs. The highest mean dust concentrations (about 20%) were found in nodules and massive fibrosis. Overall there were no significant differences between the selected lesion types and their respective whole lung dust composition, although the central sites of massive fibrosis were found to contain on average a higher proportion of coal and a lower proportion of ash and its measured constituents, quartz and kaolin plus mica, than the edge of the lesion (p less than 0.001 for each component). There were striking differences between recovered lung and lymph node dusts. An examination of 180 specimens showed a mean quartz in lymph node dust of 20.3% compared with 6.1% in lung dust. As expected the proportion of quartz was greater in lymph nodes and lungs from men who had worked "low" rank (high ash) coal. By contrast with the corresponding figures for lung dusts, however, the mean proportion of quartz in nodes did not increase over the pathological range of pneumoconiotic lung disease. On average the proportions of kaolin and mica in lymph nodes reflect those found in lungs. The lymphotrophic nature of quartz was clearly shown although it was not possible to show an association between this clearance pathway and any particular type of lesion.  相似文献   
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The Edinburgh surgical statistics (audit) have been analysed for the years 1959, 1964, 1969, 1974, and 1979 to determine the trends in pulmonary embolism in surgical patients who died. There was a total of 61,038 operations, 1528 postoperative deaths, 804 necropsies, and 158 reported pulmonary emboli. The incidence of embolism diagnosed clinically and at necropsy fell throughout the period. This fall held good after corrections for necropsy rates, prognosis, and proportions of major operations. Although the overall necropsy rate fell from 58% to 40%, in patients expected to have a good prognosis the rate rose from 68% to 75%. Necropsy-proved embolism in "good prognosis" patients fell from 0.5% to 0.15% per 100 major operations. The main reduction has taken place since most surgeons in the area adopted methods of prophylaxis against venous thrombosis, but a direct relationship is not proved by this study.  相似文献   
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Operations for hernia and varicose veins in a day-bed unit   总被引:3,自引:0,他引:3  
Over eight years (1970-8) 1055 patients underwent operations for hernia or "major" varicose veins in a day-bed unit. Here, 608 were discharged home on the day of operation, 262 were transferred to a convalescent hospital for 48 hours, and 161 were retained in the acute ward as part of a controlled trial. Special emphasis was placed on selection and preadmission screening. Failure of planning was uncommon in that only 2.5% were detained in hospital and 1% had to be readmitted. About one-quarter of the patients had complications but these were generally trivial and were satisfactorily treated by the community nursing sisters or general practitioners, or both. Analysis of the total operations for hernia or varicose veins in the unit over the past 19 years shows that, whereas formerly all patients with these conditions were admitted to the main surgical ward, nowadays almost all are managed either by day care or in a five-day ward.  相似文献   
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Background  

Purified water for pharmaceutical purposes must be free of microbial contamination and pyrogens. Even with the additional sanitary and disinfecting treatments applied to the system (sequential operational stages), Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas alcaligenes, Pseudomonas picketti, Flavobacterium aureum, Acinetobacter lowffi and Pseudomonas diminuta were isolated and identified from a thirteen-stage purification system. To evaluate the efficacy of the chemical agents used in the disinfecting process along with those used to adjust chemical characteristics of the system, over the identified bacteria, the kinetic parameter of killing time (D-value) necessary to inactivate 90% of the initial bioburden (decimal reduction time) was experimentally determined.  相似文献   
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