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61.
The effect of the level or source of dietary protein or protein-derived peptides on Ca absorption is not well understood. We determined, therefore, the influence of habitual dietary casein level, meal casein and meal casein phosphopeptide (CPP) on Ca absorption in the rat. True fractional Ca absorption was investigated in male 7-week-old rats, Wistar strain, in three separate studies using a faecal 47Sc: 47Ca ratio method. In studies A and C, rats (n 8 per group) were fed on a purified diet containing 200 g casein/kg for 2 weeks. Rats were then given a 47Ca-labelled meal (10 g) containing (per kg) either 0, 100, 200, or 300 g casein (study A) or 0, 100, 200, 350 or 500 g CPP (study C). In study B, rats (n 24 per group) were fed on a purified diet containing (per kg) either 200, 350 or 500 g casein for 2 weeks. Each group was then further randomized into three groups (n 8 per group) and given a 47Ca-labelled meal (10 g of the same diet) containing (per kg) either 200, 350 or 500 g casein. Ca absorption from a meal was unaffected by increasing meal casein concentration from 0 to 300 g/kg (study A), but was increased with a meal casein content of 500 g/kg (study B). Fractional Ca absorption decreased with increasing usual dietary casein intake in the range 200-500 g/kg (study B), suggesting intestinal adaptation. Ca absorption was unaffected by inclusion of 100 g CPP/kg in a single meal but was significantly (P < 0.001) reduced by 200, 350 and 500 g CPP/kg meal, with no evident dose-relationship. Thus, while Ca absorption was enhanced by high-casein meals, the mechanism remains unclear.  相似文献   
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This study is a combined modality Phase II therapeutic trial to determine the efficacy of the novel combination of VP-16, Vincristine and Procarbazine in addition to postoperative radiation therapy in patients with high grade intracranial gliomas. Thirty three patients (median age 51 years) were entered (27 with glioblastoma multiforme, 6 with anaplastic astrocytoma). Toxicity was manageable with no lethal toxicities. Five of seven life threatening toxicities were hematologic. Median overall survival was 14.2 months. These data suggest this regimen is effective treatment for patients with high grade gliomas.  相似文献   
64.
This study represents the experience of the Department of Surgery at the University of Louisville over a 21-year interval. Many aspects of surgical management of hyperparathyroidism have changed over the last 2 decades; controversies regarding the extent of exploration and the value of preoperative localization studies remain unresolved. One hundred ninety-three patients underwent neck exploration for hyperparathyroidism from 1976 to 1997. Data were collected from four University of Louisville-affiliated hospitals by independent evaluators. One hundred sixty patients with untreated hyperparathyroidism underwent neck exploration. Preoperative localization was carried out in 52 per cent (83 of 160). The exact location of the abnormal gland was indicated in 55 per cent (46 of 83), and the correct side of the neck was identified in 74 per cent (61 of 83). Technetium sestamibi scan was most reliable and identified the abnormality in 83 per cent (24 of 29). The average operative time with preoperative localization was 118 minutes compared with 137 minutes without preoperative localization. Intraoperative methylene blue was used in 42 of 160 neck explorations. Average operative time with methylene blue was 102 minutes compared with 124 minutes without methylene blue. Thirty-seven per cent (59 of 160) of patients underwent unilateral neck exploration. Sixty-three per cent (101 of 160) underwent bilateral exploration. Successful exploration was conducted in 98 per cent of the unilateral group and 91 per cent of the bilateral group. Postoperative local complications were essentially the same in both groups (3%), whereas temporary hypocalcemia occurred in 24 per cent (24 of 101) of the bilateral group compared with 3 per cent (2 of 59) of the unilateral group. We conclude that neck exploration for hyperparathyroidism is a highly successful, safe treatment with no mortality and minimal morbidity. Preoperative localization studies modestly reduced the duration of surgery without improving outcome.  相似文献   
65.


The management of colorectal cancers, published in a recent issue of Effective Health Care, is reviewed.  相似文献   
66.
Traditionally, different approaches have been used to determine the recommended dietary allowances for micronutrients, above which there is a low risk of deficiency, and safe upper levels, below which there is a negligible risk of toxicity. The advice given to risk managers has been in the form of point estimates, such as the recommended dietary allowance (RDA) and the tolerable upper level (UL). In future, the gap between the two intake–response curves may become narrower, as more sensitive indicators of deficiency and toxicity are used, and as health benefits above the recommended daily allowance are taken into account. This paper reviews the traditional approaches and proposes a novel approach to compare beneficial and adverse effects across intake levels. This model can provide advice for risk managers in a form that will allow the risk of deficiency or the risk of not experiencing the benefit to be weighed against the risk of toxicity. The model extends the approach used to estimate recommended dietary allowances to make it applicable to both beneficial and adverse effects and to extend the intake–incidence data to provide a range of estimates that can be considered by the risk manager. The data-requirements of the model are the incidence of a response at one or more levels of intake, and a suitable coefficient of variation to represent the person-to-person variations within the human population. A coefficient of variation of 10% or 15% has been used for established recommended dietary allowances and a value of 15% is proposed as default for considerations of benefit. A coefficient of variation of 45% is proposed as default for considerations of toxicity, based on analyses of human variability in the fate and effects of therapeutic drugs. Using this approach risk managers, working closely with risk assessors, will be able to define ranges of intake based on a balance between the risks of deficiency (or lack of benefit) and toxicity.  相似文献   
67.
Fourteen patients with macular detachments caused by optic nerve pits were treated for progressive visual loss, cystoid macular changes, or atrophy of the macular retinal pigment epithelium. Photocoagulation of the temporal disc border alone was unsuccessful in two cases but promptly reattached the macula of two patients immobilized after laser surgery. Vitrectomy and gas tamponade improved vision and flattened the macula of three patients over various periods. The detachment recurred in one patient. Prompt and sustained macular reattachment with improved vision was noted after photocoagulation, vitrectomy, and gas tamponade in eight patients, although four required second operations. The prompt reattachment and visual recovery noted in these eight patients surpasses the reported 25% rate of spontaneous resolution.  相似文献   
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The prevalence of childhood obesity is increasing worldwide with long‐term health consequences. Effective strategies to stem the rising childhood obesity rates are needed but systematic reviews of interventions have reported inconsistent effects. Evaluation of interventions could provide more practically relevant information when considered in the context of the setting in which the intervention was delivered. This systematic review has evaluated diet and physical activity interventions aimed at reducing obesity in children, from birth to 5 years old, by intervention setting. A systematic review of the literature, consistent with Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines, was performed. Three electronic databases were searched from 2010 up to December 2020 for randomised controlled trials aiming to prevent or treat childhood obesity in children up to 5 years old. The studies were stratified according to the setting in which the intervention was conducted. Twenty‐eight studies were identified and included interventions in childcare/school (n = 11), home (n = 5), community (n = 5), hospital (n = 4), e‐health (n = 2) and mixed (n = 1) settings. Thirteen (46%) interventions led to improvements in childhood obesity measures, including body mass index z‐score and body fat percentage, 12 of which included both parental/family‐based interventions in conjunction with modifying the child''s diet and physical activity behaviours. Home‐based interventions were identified as the most effective setting as four out of five studies reported significant changes in the child''s weight outcomes. Interventions conducted in the home setting and those which included parents/families were effective in preventing childhood obesity. These findings should be considered when developing optimal strategies for the prevention of childhood obesity.  相似文献   
70.
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