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Dietary supplementation with vitamin K(1), with vitamin D(3) and calcium or their combination, was examined in healthy older women during a 2-year, double-blind, placebo-controlled trial. Combined vitamin K with vitamin D plus calcium was associated with a modest but significant increase in BMC at the ultradistal radius but not at other sites in the hip or radius. INTRODUCTION: The putative beneficial role of high dietary vitamin K(1) (phylloquinone) on BMD and the possibility of interactive benefits with vitamin D were studied in a 2-year double-blind, placebo-controlled trial in healthy Scottish women > or =60 years of age. MATERIALS AND METHODS: Healthy, nonosteoporotic women (n = 244) were randomized to receive either (1) placebo, (2) 200 microg/day vitamin K(1), (3) 10 microg (400 IU) vitamin D(3) plus 1000 mg calcium/day, or (4) combined vitamins K(1) and D(3) plus calcium. Baseline and 6-month measurements included DXA bone mineral scans of the hip and wrist, markers of bone turnover, and vitamin status. Supplementation effects were tested using multivariate general linear modeling, with full adjustment for baseline and potential confounding variables. RESULTS: Significant bone mineral loss was seen only at the mid-distal radius but with no significant difference between groups. However, women who took combined vitamin K and vitamin D plus calcium showed a significant and sustained increase in both BMD and BMC at the site of the ultradistal radius. Serum status indicators responded significantly to respective supplementation with vitamins K and D. Over 2 years, serum vitamin K(1) increased by 157% (p < 0.001), the percentage of undercarboxylated osteocalcin (%GluOC) decreased by 51% (p < 0.001), serum 25-hydroxyvitamin D [25(OH)D] increased by 17% (p < 0.001), and PTH decreased by 11% (p = 0.049). CONCLUSIONS: These results provide evidence of a modest synergy in healthy older women from nutritionally relevant intakes of vitamin K(1) together with supplements of calcium plus moderate vitamin D(3) to enhance BMC at the ultradistal radius, a site consisting of principally trabecular bone. The substantial increase in gamma-carboxylation of osteocalcin by vitamin K may have long-term benefits and is potentially achievable by increased dietary intakes of vitamin K rather than by supplementation.  相似文献   
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Regeneration of human liver was long suspected to occur. It was proven in animals 100 years ago but could not be demonstrated in man until liver biopsy and modern hepatic tests became available. Structural changes in the regenerating liver mainly concern the arrangement of liver cell plates and the size and appearance of hepatocytic nuclei. A return to normalcy in test results depends on the factors responsible for regeneration since various test results change at different rates. Mass, estimated by imaging procedures, is restored parallel with the return of function. Shape is not restored but the pressure of neighboring organs and structures molds the growing remnant so that it almost resembles the original. Factors regulating regeneration in man are beginning to be recognized as they have been in animals. The hope is that regeneration can be accelerated or that cells can be transplanted to replace those lost.  相似文献   
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The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs.  相似文献   
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Regulation of thrombin generation and functions   总被引:14,自引:0,他引:14  
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'Cialit' as a tissue preservative: a microbiological assessment   总被引:1,自引:0,他引:1  
We describe bacterial contamination of a 'Cialit'-preserved cartilage bank which continued after a variety of changes to the harvesting and preservation protocols during a 3-year prospective study. Our results emphasize the importance of adequate tissue bank microbiological screening. Alternative methods of tissue preservation should be considered.  相似文献   
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