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11.
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   
12.
In an effort to improve Health Risk Appraisals and to induce individuals to change their lifestyles, comprehensive evaluations and counseling sessions were carried out for 476 participants of an experimental preventive care program (1984). Nurse practitioners interviewed participants in their homes and collected information about their lifestyle, medical history, and family history. In addition, physical examinations were performed and blood samples were obtained for laboratory analysis. This information was used to formulate health risk profiles for all participants who were then counseled on how to decrease identified health risks. Interventions included education about health risks and specific programs which were administered to help modify high-risk behaviors. At one year follow-up, significant risk reductions were reported in many areas of increased risk.Victor W. Acquista, M.D., is a Fellow in General Internal Medicine, Rhode Island Hospital. Tom J. Wachtel, M.D., is Director, Medical Primary Care Unit, Rhode Island Hospital, and Assistant Professor of Community Health, Brown University. Celia I. Gomes, M.P.H., is Health Education Coordinator, Blue Cross/Blue Shield of Rhode Island. Michael Salzillo, M.S., is Team Leader, Statistical Analysis Department, Blue Cross/Blue Shield of Rhode Island. Melanie Stockman, R.N., is Director of Ambulatory Nursing, Rhode Island Hospital.  相似文献   
13.
Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively.  相似文献   
14.
15.
Measurements of respiratory mechanics are frequently made in ventilated infants and children. Esophageal pressure measurements (Pes using a balloon on a catheter have been used to partition the respiratory mechanics into lung and chest wall components. Appropriate positioning of this balloon is crucial to obtain accurate estimates of pleural pressure. Traditionally, in spontaneously breathing subjects the balloon position is assessed with an occlusion test. In ventilated subjects, it is not always possible to perform an occlusion test prior to paralysis, and even if such a test is performed it may not be relevant under conditions of positive pressure ventilation. We have assessed a positive pressure occlusion test that is suitable for paralyzed subjects. By occluding the airway opening and applying gentle pressure to the abdomen or rib cage, positive swings in pressure can be measured by both Pes and airway opening pressure (Pao). We compared traditional occlusion tests measured in 16 spontaneously breathing puppies to the positive pressure occlusion test performed after paralysis. In 2 pups we were unable to obtain a reasonable traditional occlusion test (>15% difference between Pes and Pao) but we obtained 10 traditional occlusion tests in each of the remaining 14 pups (2.1–14 kg). In 11 of these animals Ape, was within 10% of Pao. This compared well to positive pressure occlusion test using abdominal pressure performed after paralysis, where Apes was within 10% of ΔPao in 10 animals. In 9 of these pups occlusion tests were also performed by applying pressure on the rib cage, where ΔPes was within 10% of ΔPao in 6 animals. These results suggest that it is possible to perform accurate occlusion tests in paralyzed subjects by abdominal or rib cage compression with the airway occluded. Pediatr Pulmonol. 1994; 17:56–62. © 1994 Wiley-Liss, Inc.  相似文献   
16.
The mechanism by which S-adenosylmethionine (SAM) and adenosine (Ado) increase ATP levels in intact human erythrocytes in vitro has been compared. The use of erythrocytes from healthy controls and from subjects totally deficient in adenine phosphoribosyltransferase (APRT), plus inhibitors of adenosine kinase (AK) and adenosine deaminase (ADA) separately and together, has enabled us to demonstrate that this increment in ATP levels occurred via totally different metabolic routes. The results show that: (i) whilst the Ado-induced increment in ATP was AK dependent, that produced by SAM was independent of AK; and (ii) the SAM-induced increment in ATP was totally dependent on APRT and that some of the increment produced by Ado might also be APRT dependent. The above data are consistent with the metabolism of SAM to ATP by a route recently identified by us whereby ATP is formed from deoxyadenosine: namely binding to the enzyme S-adenosylhomocysteine hydrolase with subsequent release of adenine and further conversion to ATP via APRT.  相似文献   
17.
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome.  相似文献   
18.
Goh  B.K.  AngP.  Wu  Y.J.  Goh  C.L.  潘敏 《世界核心医学期刊文摘》2006,2(8):34-35
背景:大多数已报道的基底细胞癌(BCCs)的特征主要是依据高加索患者。而关于亚洲人中不完全切除BCCs的特征少见报道。目的:本研究调查了新加坡亚洲居民的BCCs特征,并对常规外科切除术后完全切除与不完全切除肿瘤进行了比较。患者和方法:收集1991--1995年间在国家皮肤病中心行肿瘤切除术的原发性BCC患者的病历进行回顾性研究。结果:166例BCC患者(男女比0.95;平均年龄70.9岁)的185个组织病检确诊的BCCs记录在案。发病最高比例(27.1%)在8l~90岁年龄组。与普查资料相比,华人BCCs患者的比例明显增高(P〈0.001)。肿瘤平均直径为12.0mm,且大多数(84.3%)位于头颈部。28处(15.1%)皮损被不完全切除,多位于鼻部及鼻唇沟。不完全切除的基底细胞癌较完全切除的基底细胞癌更多发生于面中部及躯干部(P=0.003),但与肿瘤大小、肿瘤持续时间、患者年龄、种族及性别无显著相关。平均随访74个月,  相似文献   
19.
Purpose: The aim of the study was to provide information about the characteristics of three main types of orthokeratology (ortho‐k) lenses used in Hong Kong and to report on their performance based on the clinical impressions of a group of ortho‐k practitioners. Method: Twelve ortho‐k practitioners were interviewed between 1 March and 30 June 2001. Results: Most ortho‐k lenses were ordered from three manufacturers: DreimLens, Fargo and Contex. The median maximum myopia reduction reported for DreimLens, Contex and Fargo lenses were 6.25 D, 6.00 D and 4.50 D respectively. The time to reduce myopia by up to 4.00 D could be up to three weeks for Contex and DreimLens and up to four weeks for Fargo. For reduction of myopia by up to 4.00 D, the treatment usually required only one or two lenses per eye for all three types of lenses. The incidence of lens binding and lens tightening after achieving the optimal reduction was reported to be higher with the DreimLens design. Good centration, less lens binding, relatively lower incidence of complications and lens tightening after achieving the optimal reduction were reported with the Fargo lenses. Conclusions: DreimLens tended to be more effective for myopia reduction. However, some practitioners were concerned with the aggressiveness of myopia reduction using this lens design and the higher potential for ocular complications. Selection of the lens design is dependent on various factors, in particular, practitioners need to be comfortable with the design they choose and to consider the needs of their patients and the final goal of the treatment.  相似文献   
20.
中西医结合医院单病种的质量管理及其作用   总被引:1,自引:0,他引:1  
针对中西医结合医院单病种质量评定没有现成的、规范的标准的现状,就中西医结合单病种的质量管理方法及其在中西医结合医院建设中的作用进行了论述。  相似文献   
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