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91.
92.
Bates CJ Prentice A Cole TJ van der Pols JC Doyle W Finch S Smithers G Clarke PC 《The British journal of nutrition》1999,82(1):7-15
The aims of the National Diet and Nutrition Survey series are summarized, and the new National Diet and Nutrition Survey of people aged 65 years and over is explored, with particular emphasis on micronutrient intakes and status indices. Mean nutrient intakes were generally satisfactory for most micronutrients, but intakes of vitamin D, Mg, K and Cu were low. Intakes of vitamin D were far below the reference nutrient intake for people aged 65 years and over, and there was also biochemical evidence of vitamin D deficiency, for 8% of free-living and 37% of institution participants, attributed partly to limited exposure to sunlight. A substantial proportion of people living in institutions had inadequate biochemical status indices, notably for vitamin C, Fe and folate. Relationships between intake and status were close for vitamins. Mineral intakes did not correlate well with currently used status indices. Some intakes and indices, especially those of vitamin C, carotenoids, Na and K, were strongly correlated with socio-economic status and with north-south gradients in Britain. Future research challenges should address the functional and health significance of low intakes and sub-optimal biochemical indices for certain micronutrients, especially for people living in institutions; the shortcomings of mineral status indices especially as indicators of mineral intake; the social and geographical inequalities of micronutrient intakes and status, and why micronutrient status deteriorates with increasing age. The answers to these questions will help to define the characteristics of nutritional risk for older people in Britain, and to clarify future needs for education and intervention. 相似文献
93.
Nuclear industry family study:methods and description of a United Kingdom study linking occupational information held by employers to reproduction and child health 下载免费PDF全文
Maconochie N Doyle P Roman E Davies G Smith PG Beral V 《Occupational and environmental medicine》1999,56(12):798-808
OBJECTION: To describe the methods used in the nuclear industry family study for which a comprehensive database has been assembled that links employment in the nuclear industry and dosimetry records to information on employees'' reproductive health and the health of their children. To discuss the response rates and characteristics of the study population. METHODS: Occupational cohort design leading to a retrospective cohort study of reproductive outcomes reported by 46 396 current and former employees of both sexes in the nuclear industry. Employees of nuclear establishments in the United Kingdom operated by the Atomic Energy Authority, the Atomic Weapons Establishment, and British Nuclear Fuels were surveyed with postal questionnaires ot collect information on pregnancies, children,and periods of infertility. Information on employment and monitoring for ionising radiation was supplied by the employing nuclear authority and was linked to pregnancies and periods of infertility with unique personal identification numbers. RESULTS: The design and completion of this study resulted in high quality data on a representative population of the Atomic Energy Authority, Atomic Weapons Establishment, and British Nuclear Fuels workforces. The response to the survey was extremely good (82% for male workers and 88% for female workers, excluding undelivered questionnaires), and a unique relational database has been created which will enable infertility, pregnancy, and child health outcomes to be examined with respect to the employment and radiation monitoring characteristics of parents. CONCLUSION: This is the first United Kingdom study to link detailed reproductive history data to occupational information held by employers. The methods developed for the study were found to be feasible and successful. The design can be adapted for other investigations of reproductive hazards to men and women in the workplace and is currently in use to survey over 100 000 armed forces personnel in an investigation of reproductive outcome among veterans of the Gulf war. 相似文献
94.
The current study investigated the effect of erbium filtration on an anteroposterior abdominal image. The radiation dose
reductions achieveable and the costeffectiveness of this filter were also evaluated. An assessment of the radiation dose delivered
employing either the standard total filtration (3 mm Al equivalent) or 0.1 mm of erbium filtration added to the standard filtration
was undertaken on 21 patients. Image quality was assessed using the Commission of European Communities (CEC) criteria. Significant
reductions of 64.6 % in entrance surface (p = 0.0001) and 23.4 % in effective dose (p = 0.0099) were recorded with erbium
filtration. Image quality was maintained and the cost per manSievert saved was £ 128. More widespread use of this dose reducing
filter is advocated.
Received: 7 August 1998; Revised: 19 February 1999; Accepted: 19 April 1999 相似文献
95.
Predicting infection in localized intraabdominal fluid collections: value of pH and pO2 measurements
Wong JK Mustard R Gray RR Sadler DJ Sanabria J Bohnen JM Schouten BD Doyle G Pugash RA 《Journal of vascular and interventional radiology : JVIR》1999,10(4):421-427
PURPOSE: To evaluate the use of pH, pO2, and the subjective opinion of the radiologist compared with bacterial culture in accurate diagnoses of bacterial infection in intraabdominal fluid collections. MATERIALS AND METHODS: Prospectively, 79 patients who were suspected of having an intraabdominal fluid collection underwent diagnostic fluid aspiration. The aspirate was cultured and measured for pH and pO2. A pH < or = 7.1 and a PO2 < or = 49 mm Hg were threshold values used to separate infected from sterile fluid collections. RESULTS: pH alone had a 92% sensitivity and 79% specificity, whereas PO2 alone had a 51% sensitivity and 79% specificity. pH or pO2 combined yielded a 92% sensitivity and 60% specificity. The radiologist's opinion produced a 83% sensitivity and 92% specificity. pH and the radiologist's opinion combined produced a 78% sensitivity and 96% specificity. pH or the radiologist's opinion combined had a 95% sensitivity and a 63% specificity. CONCLUSION: pH is the most sensitive indicator of infection and the radiologist's opinion is the most specific. We recommend proceeding to drainage if the radiologist believes the collection to be infected and performing pH analysis if not. If the pH < or = 7.04, proceed to drainage. If neither of the above criteria are met, drainage could be delayed, pending the results of culture. 相似文献
96.
A C Pereira D E Saunders V L Doyle J M Bland F A Howe J R Griffiths M M Brown 《Stroke; a journal of cerebral circulation》1999,30(8):1577-1582
BACKGROUND AND PURPOSE: (1)H MR spectroscopy can be used to study biochemical changes occurring in the brain in stroke. We used it to examine the relationship between metabolite concentration (N-acetyl aspartate [NAA], lactate, cholines and creatines), size of infarct, clinical deficit, and 3-month clinical outcome in patients with middle cerebral artery (MCA) territory infarction. METHODS: Thirty-one patients with acute MCA territory infarction were recruited within 72 hours of the onset of symptoms. Single-voxel short echo time stimulated echo acquistion mode spectroscopy was used to obtain metabolite data from the infarct core. Metabolite concentrations were determined with use of variable projection time domain-fitting analysis. Infarct size was determined with T2-weighted images. Patient outcome groups at 3 months were "independent," "dependent," or "dead." RESULTS: All patients (100%; 95% CI 75% to 100%) who had an infarct >70 mL did poorly. Eighteen of 20 patients (90%; 95% CI 68% to 99%) with a core NAA concentration <7 mmol/L did poorly at 3 months, whereas 7 of 11 patients (64%; 95% CI 31% to 89%) with an initial NAA concentration >7 mmol/L did well. Combining these results showed that all patients who had an initial infarct volume >70 mL did poorly, irrespective of the NAA concentration. Of those patients with infarcts <70 mL, those who had a core NAA concentration >7 mmol/L did well (88%; 95% CI 47% to 100%), whereas those with a lower NAA concentration did poorly (80%; 95% CI 44% to 97%). There was no association between other metabolite concentrations and outcome. CONCLUSIONS: Infarct volume and NAA concentration can together predict clinical outcome in MCA infarction in humans. 相似文献
97.
98.
Methods for the acquisition and analysis of intracranial pressure (ICP) signals are reviewed from clinical and technical perspectives. The clinical importance of ICP monitoring is presented, and methods for ICP transduction are briefly discussed. These methods include intraventricular catheters, subarachnoid screws, epidural techniques, and the new fiberoptic ICP measurement systems. Approaches to the visual analysis of the ICP waveform are presented, with special emphasis on the relationship between the ICP waveform and the arterial blood pressure signal. Methods of computer-based ICP analysis are also reviewed, including histogram and systems analysis methods. Methods to predict ICP pressure rises and to estimate intracranial compliance are also discussed. Finally, ICP monitoring is reviewed from the point of view of patient outcome. It is concluded that advanced ICP waveform analysis methods warrant further clinical evaluation to demonstrate their clinical usefulness. 相似文献
99.
A causal connection between maternal nutrient intake and birth outcome is not universally accepted. In this paper further empirical support is provided, particularly in relation to the impact of maternal nutrition around the time of conception or very early in pregnancy. It is argued that the hypothesis that maternal nutrition has no connection with birthweight is very easily refuted. It is suggested that there should be a new category of recommended dietary allowances; "women in anticipation of pregnancy". The diet of 513 pregnant London women were recorded for 7 days during the first trimester of their pregnancy. Birthweight and nutrient intakes were found to be significantly correlated but only over the lower half of the birthweight range. The optimum birthweight range with the lowest perinatal and infant mortalities is 3,500-4,500 g and it is suggested that the nutrient intake of th 165 women who had babies in this optimum weight range provide tentative values for nutrient intake recommendations in anticipation of pregnancy, but are not claimed to be representative. The need for adjustments of recommendations for the individual, for example for a low body mass index, is discussed. A body mass index of 24 kg/m2 is recommended based on the median of the 165 women. 相似文献
100.
Comparative trial of mexiletine and lignocaine in the treatment of early ventricular tachyarrhythmias after acute myocardial infarction 总被引:1,自引:0,他引:1
J D Horowitz S N Anavekar P M Morris A J Goble A E Doyle W J Louis 《Journal of cardiovascular pharmacology》1981,3(3):409-419
The antiarrhythmic effects of intravenously administered lignocaine and mexiletine were compared over a period of 48 hr in a randomized trial on 24 patients who developed ventricular tachyarrhythmias within 48 hr of the onset of acute myocardial infarction. Mexiletine was given as an initial bolus of 200 mg, followed by an infusion of 1 mg/min reduced to 0.5 mg/min after 1 hr. Lignocaine was given as a bolus of 100 mg, followed by an infusion of 3 mg/min reduced to 2 mg/min after 1 hr. Plasma levels of mexiletine, lignocaine, and monoethylglycinexylidide were monitored. The frequency of "complex" ventricular tachyarrhythmias was significantly lower in the mexiletine-treated group. This group of patients also had significantly fewer ventricular extrasystoles than those receiving lignocaine, the difference being most marked during the second 24 hr of treatment. Too few episodes of ventricular fibrillation occurred for statistical comment. The greater efficacy of mexiletine was not associated with increased drug toxicity. 相似文献