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61.
Developments in radiotherapy 总被引:1,自引:0,他引:1
A systematic assessment of radiotherapy for cancer was conducted by The Swedish Council on Technology Assessment in Health Care (SBU) in 2001. The assessment included a review of future developments in radiotherapy and an estimate of the potential benefits of improved radiotherapy in Sweden. The conclusions reached from this review can be summarized as: Successively better knowledge is available on dose-response relationships for tumours and normal tissues at different fractionation schedules and treated volumes. Optimization of dose levels and fractionation schedules should improve the treatment outcome. Improved treatment results may be expected with even more optimized fractionation schedules. The radiosensitivity of the tumour is dependent on the availability of free oxygen in the cells. The oxygen effect has been studied for a long time and new knowledge has emerged, but there is still no consensus on the best way to minimize its negative effect in the treatment of hypoxic tumours. Development in imaging techniques is rapid, improving accuracy in outlining targets and organs at risk. This is a prerequisite for advanced treatment planning. More accurate treatment can be obtained using all the computer techniques that are successively made available for calculating dose distributions, controlling the accelerator and multileaf collimator (MLC) and checking patient set-up. Optimized treatment plans can be achieved using inverse dose planning and intensity modulation radiation therapy (IMRT). Optimization algorithms based on biological data from clinical trials could be a part of future dose planning. New genetic markers might be developed that give a measure of the radiation responsiveness of tumours and normal tissue. This could lead to more individualized treatments. New types of radiation sources may be expected: protons, light ions, and improved beams (and compounds) for boron neutron capture therapy (BNCT). Proton accelerators with scanned-beam systems and energy modulation give good dose distribution. The results reported with carbon ions from Japan and Germany are promising. An interesting development is to verify the dose and position for the irradiated volume with PET on line. Safer margins are obtained and the treatment volume can thus be limited. Very large accelerators are needed to accelerate the carbon ions. Still, it should be possible to keep the costs per patient at the same level as those for other types of advanced radiotherapy, since far fewer treatments per patient are needed. It might also be possible to treat new groups of patients. Increased resources are needed to introduce all the currently available techniques. New types of particle accelerators require large investments and a new structure of radiotherapy in Sweden. 相似文献
62.
Norlund A;SBU Survey Group 《Acta oncologica (Stockholm, Sweden)》2003,42(5-6):411-415
A systematic assessment of radiotherapy for cancer was conducted by The Swedish Council on Technology Assessment in Health Care (SBU) in 2001. The assessment included an overview of the capacity for radiotherapy in terms of infrastructure of cancer care and an estimation of the costs of radiotherapy in Sweden. A postal questionnaire distributed to all 16 centres of radiotherapy in Sweden showed the following results: In 2000 there were 57 accelerators with complementary equipment in operation, 24 of which had been installed 10 or more years ago earlier. The total cost of external radiation therapy was estimated at SEK 427 million in the year 2000, or approximately 5% of the estimated total cost of oncology care in Sweden. The total cost of brachytherapy was estimated at SEK 43 million or about one-tenth of that of external radiotherapy. The total cost of external radiotherapy has increased since the last inquiry (1991) by about 16% more than the general inflation in Sweden, but at the same time the volume of fractions has increased by about 37%. Thus, an increase in the efficiency of external radiotherapy, calculated per fraction, was achieved in the 1990s. At the department level, there was a clear correlation between cost of salaries and output of fractions of external radiotherapy, thus indicating the adaptation of manpower to the volume of patients. There was an even higher correlation between the number of accelerators and the volume of fractions of radiotherapy, which suggests the occurrence of certain economies of scale in Swedish external radiotherapy. 相似文献
63.
Smith RA Saslow D Sawyer KA Burke W Costanza ME Evans WP Foster RS Hendrick E Eyre HJ Sener S;American Cancer Society High-Risk Work Group;American Cancer Society Screening Older Women Work Group;American Cancer Society Mammography Work Group;American Cancer Society Physical Examination Work Group;American Cancer Society New Technologies Work Group;American Cancer Society Breast Cancer Advisory Group 《CA: a cancer journal for clinicians》2003,53(3):141-169
In 2003, the American Cancer Society updated its guidelines for early detection of breast cancer based on recommendations from a formal review of evidence and a recent workshop. The new screening recommendations address screening mammography, physical examination, screening older women and women with comorbid conditions, screening women at high risk, and new screening technologies. 相似文献
64.
Kuhnlein HV Johns T;IUNS Task Force On Indigenous Peoples' Food Systems Nutrition 《Asia Pacific journal of clinical nutrition》2003,12(3):344-349
This paper describes cultural and ecological characteristics of Northwest African and Middle Eastern food patterns and discusses the forces contributing to rapid dietary change. Focus is given to indigenous/tribal/ethnic/minorities in these areas with contributions to definitions of these groups, the extent of their diversity, and the importance of their traditional knowledge of local food resources. Urbanization, particularly for those facing extreme poverty in the urban environment, is recognized as a significant force to dietary change and consequent poor nutrition, especially for children. Examples of food systems are given for the coastal zone of West Africa and the semi-arid and desert zones of North Africa and the Middle East, also including the food system of Pharaonic times. Trends in dietary change are presented as data derived from FAO Food Balance Sheets. 相似文献
65.
Rudolph CD Mazur LJ Liptak GS Baker RD Boyle JT Colletti RB Gerson WT Werlin SL;North American Society for Pediatric Gastroenterology Nutrition 《Journal of pediatric gastroenterology and nutrition》2001,32(Z2):S1-31
Gastroesophageal reflux (GER), defined as passage of gastric contents into the esophagus, and GER disease (GERD), defined as symptoms or complications of GER, are common pediatric problems encountered by both primary and specialty medical providers. Clinical manifestations of GERD in children include vomiting, poor weight gain, dysphagia, abdominal or substernal pain, esophagitis and respiratory disorders. The GER Guideline Committee of the North American Society for Pediatric Gastroenterology and Nutrition has formulated a clinical practice guideline for the management of pediatric GER. The GER Guideline Committee, consisting of a primary care pediatrician, two clinical epidemiologists (who also practice primary care pediatrics) and five pediatric gastroenterologists, based its recommendations on an integration of a comprehensive and systematic review of the medical literature combined with expert opinion. Consensus was achieved through Nominal Group Technique, a structured quantitative method. The Committee examined the value of diagnostic tests and treatment modalities commonly used for the management of GERD, and how those interventions can be applied to clinical situations in the infant and older child. The guideline provides recommendations for management by the primary care provider, including evaluation, initial treatment, follow-up management and indications for consultation by a specialist. The guideline also provides recommendations for management by the pediatric gastroenterologist. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology and Nutrition on the evaluation and treatment of gastroesophageal reflux in infants and children. The American Academy of Pediatrics has also endorsed these recommendations. The recommendations are summarized in a synopsis within the article. This review and recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the management of all patients with this problem. 相似文献
66.
Ganji V Kafai MR;Third National Health Nutrition Examination Survey 《The American journal of clinical nutrition》2003,77(4):826-833
BACKGROUND: Elevated serum total homocysteine (tHcy) is an independent risk factor for vascular diseases. OBJECTIVE: Associations between serum tHcy and demographics, health and lifestyle factors, and blood vitamin concentrations were investigated. DESIGN: Data from the third National Health and Nutrition Examination Survey, 1988-1994 were used to examine associations in men (n = 2965) and women (n = 3580) between tHcy and age, sex, race-ethnicity, body mass index, systolic and diastolic blood pressures, alcohol consumption, supplement use, red blood cell (RBC) folate, and serum creatinine, folate, vitamin B-12, and cotinine (a measure of cigarette smoking). RESULTS: The unadjusted mean tHcy was 21.5% ( approximately 1.9 micro mol/L) higher in men than in women, 11.8% ( approximately 1.1 micro mol/L) higher in non-Hispanic whites than in Mexican Americans, 42% ( approximately 3.7 micro mol/L) higher in persons aged > or = 70 y than in persons aged < 30 y, and 10.9% ( approximately 1.0 micro mol/L) higher in supplement nonusers than in supplement users. The tHcy concentration was negatively associated with serum folate (P < 0.0001 for trend), RBC folate (P < 0.0001 for trend), and serum vitamin B-12 (P < 0.0036 for trend) and was positively associated with alcohol consumption (P < 0.0001 for trend), serum cotinine (P < 0.0001 for trend), and systolic blood pressure (P < 0.0001 for trend). Consumption of hard liquor (but not of beer or wine) was positively associated with tHcy concentration (P < 0.0001 for trend). CONCLUSIONS: In this population-based study, the significant predictors of tHcy concentration were sex, age, race-ethnicity, serum creatinine, systolic blood pressure, body mass index, hard-liquor consumption, smoking, supplement use, serum folate, RBC folate, and serum vitamin B-12. 相似文献
67.
68.
Dwyer J Picciano MF Raiten DJ;Continuing Survery of Food Intakes by Individuals;National Health Nutrition Examination Survery 《The Journal of nutrition》2003,133(2):576S-581S
The history of the integration of the dietary data collection from the National Health and Nutrition Examination Survey (NHANES) and the Continuing Survey of Food Intakes by Individuals (CSFII) is reviewed. The purposes and process of the workshop are presented. The three key topics of the workshop are summarized. The key roles of cosponsors and participants are acknowledged. 相似文献
69.
Dwyer J Picciano MF Raiten DJ;Members of the Steering Committee;National Health Nutrition Examination Survery 《The Journal of nutrition》2003,133(2):590S-600S
This paper describes the collection process for the integrated dietary component of the National Health and Nutrition Examination Survey(NHANES) 2002 (entitled What We Eat in America-NHANES), referred to here as the integrated survey. The dietary components of previous NHANES cycles and the Continuing Survey of Food Intake in Individuals (CSFII) are also described. The collection process for foods in the integrated survey consists of an in-person 24-h recall using a computerized 5-step method and a second nonconsecutive 24-h recall via telephone. A food frequency questionnaire is being pilot-tested to provide information on the propensity to consume certain foods. Dietary supplement intakes over the past 30 d are assessed for all persons during the household interview. Other diet-related data are also obtained. Strengths of the integrated survey include information on food and supplement intakes in a representative sample of the civilian noninstitutionalized population of the United States that can be linked to anthropometric, biochemical, clinical and disease history information in NHANES. After reviewing the current state of the art on dietary and dietary supplement data collection, discussion groups consisting of members of key stakeholder community concluded that, although the most advanced methods for dietary data collection available are being used, the differences between how information on food and dietary supplement intakes is collected make it challenging to combine data describing nutrients from both sources to obtain estimates of total nutrient intakes. The discussion groups concluded that more research is needed on these issues and provided key recommendations for future efforts in this important area of public health surveillance. 相似文献
70.
Committee on Nutrition 《Pediatrics》2001,107(5):1210-1213
Historically, fruit juice was recommended by pediatricians as a source of vitamin C and an extra source of water for healthy infants and young children as their diets expanded to include solid foods with higher renal solute. Fruit juice is marketed as a healthy, natural source of vitamins and, in some instances, calcium. Because juice tastes good, children readily accept it. Although juice consumption has some benefits, it also has potential detrimental effects. Pediatricians need to be knowledgeable about juice to inform parents and patients on its appropriate uses. 相似文献