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Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. 总被引:21,自引:0,他引:21
Heike A Bischoff Hannes B St?helin Walter Dick Regula Akos Margrith Knecht Christian Salis Matthias Nebiker Robert Theiler Michael Pfeifer Bettina Begerow Robert A Lew Martin Conzelmann 《Journal of bone and mineral research》2003,18(2):343-351
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function. 相似文献
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In vivo carbon monoxide exposure and hypoxic hypoxia stimulate immediate early gene expression 总被引:4,自引:0,他引:4
Bernhard Gess Konrad Wolf Michael Pfeifer Günter A. J. Riegger A. Kurtz 《Pflügers Archiv : European journal of physiology》1997,434(5):568-574
This study aimed to examine the influence of acute tissue hypoxygenation on the expression of immediate early genes in different
rat tissues. To this end male Sprague-Dawley rats were exposed to 0.1% carbon monoxide for 0.5, 1 and 6 h or to 9% oxygen
for 6 h and mRNA levels for c-jun, c-fos, c-myc and EGR-1 were assayed by RNase protection in hearts, kidneys, livers and lungs. We found that hypoxia increased c-jun mRNA levels between twofold (lung) and eightfold (liver) in all organs examined; c-fos mRNA increased between threefold (lung) and 20-fold (heart); c-myc mRNA increased between twofold (lung) and sixfold (heart); and EGR-1 mRNA increased between twofold (lung) and sixfold (heart).
Our findings suggest that acute tissue hypoxygenation is a general stimulus of the expression of immediate early genes in
vivo. With regard to the sensitivity to hypoxia, organ differences appear to exist in that the lung is rather insensitive,
whilst the heart is rather sensitive.
Received: 25 February 1997 / Received after revision: 17 June 1997 / Accepted: 19 June 1997 相似文献
16.
Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
17.
The antiparkinsonian triperiden (1; as hydrochloride Norakin) is a mixture of the stereoisomers 1a and 1b. Their identification and separation by chromatographic methods or fractional crystallisation of the tartrates is described. By means of IR- und 13C-NMR spectral data structures of 1a and 1b are proposed. Under proton catalysis 1b racemizes to 1a. In acidic solution (heating in 0.1 mol.1-1 HCl or storage in gastric juice at 37 degrees C) hydrolysis of 1 takes place and four isomeric products were observed (Z1-Z4), which arise by cleavage of the cyclopropyl moiety. The main product Z2 was identified as the 2"-hydroxy derivative. The solid drug is stable at least for 5 years. 相似文献
18.
Pfeifer JD Ashley Hill D Ramos CV Wippold FJ II Dehner LP 《Archives of pathology & laboratory medicine》2000,124(6):898-901
A 77-year-old woman with neurofibromatosis type 1 presented with ill-fitting dentures due to intraoral extension of a right temporal fossa mass. Computed tomographic scanning demonstrated that the masticator space mass bowed the zygomatic arch and remodeled the lateral orbit and maxillary sinus walls, findings that were consistent with the clinical diagnosis of a neurofibroma with possible malignant transformation. However, light microscopic, immunohistochemical, and ultrastructural examination of tissue from an incisional biopsy specimen were diagnostic of meningioma. This case illustrates that the clinicopathologic differential diagnosis of an enlarging mass in patient with neurofibromatosis should include sporadic, unrelated neoplasms as well as tumors known to be associated with the syndrome. 相似文献
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A. Schmieder H. Jacobs H. Maurer H. Pfeifer 《Journal of molecular medicine (Berlin, Germany)》1984,62(1):35-42
Summary 42 patients with advanced stage III and IV squamous cell carcinoma of the head and neck were treated with initial cisplatin and bleomycin chemotherapy and subsequent radiotherapy. 39 were evaluable for results, and 3 for toxicity only. 8 patients suffered from stage III and 31 from stage IV tumors, of these 10 with distant metastases. 5 patients underwent later a rescue operation. 27 were previously untreated (= group A) including 2 cases with localized relapses beyond the margins of surgical and/or radiotherapeutic treatment fields. 12 patients had a recurrence within pretreated areas (= group B). The induction chemotherapy alone showed the following results: In group A 4 (15%) CR, 10 (37%) PR, 7 (26%) MR; in group B 3 (25%) PR, 2 (17%) MR. The subsequent radiotherapy mostly consisted of a 65 Gy tumor dose given in 61/2 weeks. The results after completion of the combined modality therapy were: In group A 44% CR, 28% PR; in group B 10% CR and 30% PR. No patient resistant to the initial chemotherapy responded to the radiotherapy. The median survival time of stage III patients was 20 months but only 7 months in stage IV patients. 4 of all live with NED now between 30+ and 41+ months; 1 patient is alive with relapse. All the others are dead after a survival time of max. 32 months, included the 5 with rescue operation. In general, hematologic and renal toxicities were not severe, but nausea and vomiting were the worst tolerated side effects. 1 patient died from septic myocarditis having a WBC nadir of 2000/µl, probably due to additional immunologic deficiency because of inactive liver cirrhosis. The poor results concerning NED survival are discussed. We conclude, that an initial chemotherapy with CDDP and BLM gives good remission effects but its combination with radiotherapy at present fails to produce a NED survival benefit. Further efforts are necessary to improve the CR and the long time survivor rates.
Die Autoren danken folgenden Kollegen für ihre Mitarbeit: Drs. Garbea (HNO), B. Bienko, M. Danker, N. Birke, M. Klessing, K. Lottner, W. Palm 相似文献