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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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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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The patient was diagnosed in childhood as having severe congenital neutropenia and had recurrent admissions with severe infections. In 1987, prior to getting married, she was sterilized. She continued to require i.v. antibiotics when she contracted a severe infection. On one occasion, she was treated with growth colony stimulating factor (G- CSF). Her increased neutrophil count was sustained following this treatment. In June 1993, she wished to start a family and underwent in- vitro fertilization (IVF) treatment. G-CSF was given prior to oocyte retrieval. She conceived on her first cycle and an ultrasound scan revealed a singleton pregnancy. Throughout the course of the pregnancy, her white cell count was monitored closely and remained at <1.0x10(9)/l. The pregnancy progressed uneventfully and at 37 weeks gestation she was admitted for G-CSF injections. At 38 weeks she was delivered of a boy weighing 3350 g, by elective Caesarean section. His white cell count was normal. This is the first case of G-CSF being used before conception and during pregnancy in a patient with congenital neutropenia. It shows that advances in cytokine therapy and close interdisciplinary liaison can lead to a successful outcome and help patients, who would otherwise remain childless, to achieve a family.   相似文献   
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The aim of the study was to determine whether a prior diagnostic testicle biopsy can predict success or failure of testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI) in patients with non-obstructive azoospermia caused by testicular failure, and what is the minimum threshold of sperm production in the testis which must be surpassed for spermatozoa to reach the ejaculate. Forty- five patients with non-obstructive azoospermia caused by testicular failure underwent diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure. The diagnostic testicle biopsy was analysed quantitatively, and correlated with the quantitative findings of spermatogenesis in patients with normal spermatogenesis, as well as with the results of subsequent attempts at TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure had a mean of 0-6 mature spermatids/seminiferous tubule seen on a diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in men with normal spermatogenesis and obstructive azoospermia. These findings were the same for all types of testicular failure whether Sertoli cell only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia. Twenty-two of 26 men with mature spermatids found in the prior testis biopsy had successful retrieval of spermatozoa for ICSI, 12 of their partners became pregnant, and are either ongoing or delivered. The study suggests that 4-6 mature spermatids/tubule must be present in the testis biopsy for any spermatozoa to reach the ejaculate. More than half of azoospermic patients with germinal failure have minute foci of spermatogenesis which are insufficient to produce spermatozoa in the ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for the presence of mature spermatids) can predict subsequent success or failure with TESE-ICSI. Incomplete testicular failure may involve a sparse multi-focal distribution of spermatogenesis throughout the entire testicle, rather than a regional distribution. Therefore, it is possible that massive testicular sampling from many different regions of the testes may not be necessary for successful TESE-ICSI.   相似文献   
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