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31.
Diet and cancer--an overview 总被引:5,自引:0,他引:5
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Hemoglobin Setif produces pseudosickling of red cells in vitro; the nature of the process and the conditions that "trigger" it are unknown. Studies of red cells, hemolysates, purified hemoglobin solutions, and artificial mixtures of Hb A and Setif suggest that pseudosickling is produced by intracellular crystallization of insoluble hemoglobin. Increased tonicity of the suspending medium accentuates the process, probably by causing a rise in intracellular hemoglobin concentration. If precipitates from A/Setif mixtures are analyzed, they always contain Hb A, suggesting an unusual mechanism for the process. Despite the fact that osmolality in the renal medulla is similar to that which produces pseudosickling in vitro, carriers do not have renal dysfunction of the type found in patients with sickle cell disease. 相似文献
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MacMahon L 《Health manpower management》1990,15(3):15-16
Laurie MacMahon gives his views on why we should take care when applying private-sector values to public-sector organisations like the NHS. 相似文献
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BACKGROUND: Studies of mortality from asthma and chronic obstructive pulmonary disease (COPD) have relied on death certification or registration for case finding. The aim of this study was to determine the accuracy of death certification and registration in asthma and COPD. METHODS: All death certificates in Northern Ireland for 1987 where asthma or COPD (defined as International Classification of Diseases 9th Revision (ICD9) 490, 491, 492, 496) were listed in part I or part II were identified. The following certificates were then selected for further investigation: those mentioning asthma for all ages, those mentioning COPD for ages less than 56 years, and a 50% sample of those mentioning COPD aged 56-75 years. For these selected deaths the general practitioners' case notes, hospital records, and necropsy findings were reviewed. Questionnaires detailing the clinical history and circumstances of death were completed by the general practitioner by post and by a close relative or associate of the deceased (doctor administered) if, after initial investigation, the death was likely to be due to COPD or asthma. A panel of two respiratory physicians reviewed each death and, using clinical diagnostic criteria, assessed the accuracy of the registered cause of death. RESULTS: Of 50 registered asthma deaths 43 were confirmed as being due to asthma. In nine registered deaths from COPD in cases aged less than 56 years one was confirmed as COPD, two as asthma, and six as other respiratory conditions. Of 105 registered deaths from COPD in cases aged 56-75, 42 were confirmed as COPD, 27 as asthma, eight as other respiratory conditions, and 28 as other causes. Although few errors in registration were found, 21% of certificates mentioning asthma and 38% of certificates mentioning COPD but not asthma in part I were subject to variable application of the classification rules by the registering officers. For all deaths under 75 years of age in Northern Ireland in 1987 where either asthma or COPD was mentioned anywhere on the death certificate, the estimated sensitivity and specificity of the registered cause of death in predicting the "true" cause of death were 29% and 98.6% for asthma and 69% and 70% for COPD. CONCLUSIONS: In a population of subjects where asthma or COPD was mentioned anywhere on the death certificate, the registered cause of death is a relatively poor indicator of the "true" cause of death for both asthma and COPD. Variation occurred in the application of death classification rules by registration officers. Many deaths certified and registered as COPD could have been called asthma using current standards of clinical diagnosis. In studies investigating risk factors for deaths from asthma, case finding should consider deaths registered as COPD. 相似文献
38.
An experimental apparatus was assembled that permitted measurement of the vertical and lateral ground reaction forces as the hip is abducted, resulting in foot separations ranging from 0.25 to 71 cm, with the knee in 0 degree flexion. Twelve healthy volunteers (8 men and 4 women) were tested. The hip joint was located by means of center of rotation measurements on each subject's legs, and the location of the knee joint was determined using anatomical measurements. It was observed that the mediolateral force was nonzero and directed toward the body midline, even when the subject's feet were placed together. With the feet placed at shoulder width, the population mean mediolateral force was 3% of body weight. It was determined that simplifying assumptions based upon either "zero lateral force," or "zero hip moment," produced errors, when compared with our measured values, over various ranges of foot separation, with the zero hip moment assumption providing accuracy over a broader range. The inclination of the tibial plateau, with respect to the long axis of the tibia, that would produce minimal mediolateral shear at the knee is presented. Research and clinical applications of our results and techniques are discussed. 相似文献
39.
MJ Stevens PD Stricker J Saalfeld PC Brenner R Kooner GFA O'Neill PJ Duval RS Jagavkar P Cross J Martland 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):152-160
Combination high dose rate brachytherapy (HDRB) and external beam radiation therapy is technically and clinically feasible as definitive treatment for localized prostate cancer. We report the first large Australian experience using this technique of radiation dose escalation in 82 patients with intermediate‐ and high‐risk disease. With a median follow up of 3 years (156 weeks), complications were low and overall prostate‐specific antigen progression‐free survival was 91% using the American Society for Therapeutic Radiology and Oncology consensus definition. The delivery of hypofractionated radiation through the HDRB component shortens overall treatment time and is both biologically and logistically advantageous. As a radiation boost strategy, HDRB is easy to learn and could be introduced into most facilities with brachytherapy capability. 相似文献
40.
Screening for complement deficiency in bacterial meningitis 总被引:1,自引:0,他引:1
T Ernst PJ Späth C Aebi UB Schaad MG Bianchetti 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(9):1009-1010
Seventy-seven children with bacterial meningitis were screened for complement deficiency. Both the classical and the alternate pathways were normal in 75 patients. Transiently reduced total haemolytic activity of the classical pathway was documented in a boy with meningococcal meningitis. Total haemolytic activity of both the classical and the alternate pathways were reduced in another patient with pneumococcal meningitis: individual complement components determination indicated predominant activation of the alternate pathway. 相似文献