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991.
C. Ghezzo R. Civitelli S. Cadel G. Borelli M. Maiorino L. Bufalino S. Bongrani 《Calcified tissue international》1996,59(6):496-499
We have previously found that a short-term treatment with high doses of ipriflavone increased bone density and improved the biomechanical properties of adult male rat bones, without altering their mineral composition. To determine whether this effect can be associated with alterations of bone crystal structure, we have performed X-ray diffraction analysis of bones obtained from rats treated with ipriflavone at doses that were effective in inducing favorable changes on bone density and biomechanics. Eighteen-week-old male Sprague Dawley rats were treated by oral route with either ipriflavone (200 or 400 mg/kg/day), or its vehicle for 12 weeks. The treatment was well tolerated and body weight increased to the same extent in all animals. As a measure of bone crystallinity, we examined the (310) and (002) reflections of the X-ray diffraction patterns, corresponding to the directions perpendicular and parallel to the c-axis of the crystals, respectively. No major differences were observed between ipriflavone-treated and control animals for the broadening parameter 1/2 for (310) and (002) peaks, as well as for lattice parameters. Therefore, a 12-week treatment with ipriflavone at high doses does not induce significant modifications of bone crystallinity. Thus. the positive effect of ipriflavone on bone mineral density appears to be associated with an increased apatite crystal formation rather than an increase of crystal size. These results provide further evidence for the safety and usefulness of ipriflavone in the treatment of osteoporotic syndromes. 相似文献
992.
The effect of smoking at different life stages on bone mineral density in elderly men and women 总被引:6,自引:2,他引:4
D. P. Kiel MD Y. Zhang M. T. Hannan J.J Anderson J. A. Baron D. T. Felson 《Osteoporosis international》1996,6(3):240-248
To assess the effect of smoking on bone mineral density (BMD) at different life stages, to examine whether the effect of smoking differs between men and women, and to discover whether its effect in women differs according to history of estrogen use, a cohort study was carried out with single cross-section measurement of BMD by single and dual photon absorptiometry. The setting was the Framingham Study, a population-based cohort study with over 40 years prospectively collected data on smoking. Subjects (n=1164) consisted of cohort members participating in the 20th biennial Framingham examination (1988–1989). The measurements included in the study were BMD measured at the hip, spine and radius, smoking history ascertained at all Framingham Study examinations since 1948, and other factors affecting BMD (age, weight, estrogen use, caffeine use, alcohol use and physical activity). Neither current smoking, recent (last 10 years) smoking, nor early adulthood smoking resulted in significantly lower BMD at any skeletal site among women who had not taken estrogen. Among women who had taken estrogen, BMD at most sites was lower among current or recent smokers, although the small numbers of smokers made it difficult to find significant differences at all skeletal sites. Among men, a consistently lower BMD at all skeletal sites was observed for smokers regardless of when in their life they smoked (4–15.3% lower), although the effect of smoking during early adulthood was of a lesser magnitude (4–8% lower). Former male smokers who had quit <10 years ago had lower BMD than men who had quit 10 years ago. In conclusion, in women who had used estrogen, BMD was lower in current or recent smokers than it was in non-smokers. In men, smoking at any stage of life had adverse effects on the skeleton that was independent of weight, alcohol or caffeine use, implying other mechanisms for smoking's effect on bone. 相似文献
993.
Rosemary Dziak 《Calcified tissue international》1978,26(1):65-70
Summary The vitamin D3 metabolite, 25-hydroxycholecalciferol, at concentrations of 0.01 to 10.0 g/ml, decreased calcium uptake by isolated bone cells. The effect occurred within 1 min after the simultaneous addition of metabolite and45Ca. Lactic acid and ATP production by the cells was not affected. 24(R), 25-dihydroxycholecalciferol produced a similar decrease in calcium uptake. Vitamin D3 had no effect at concentrations from 0.01 to 10.0 g/ml. No effect of 1,25-dihydroxycholecalciferol on calcium uptake was observed with concentrations from 0.1 to 100 ng/ml and various preincubation periods extending to 2 h. None of the agents had any effect on calcium efflux. The effects of 25-hydroxycholecalciferol and 24(R), 25-dihydroxycholecalciferol on calcium uptake were not seen in isolated fetal rat skin cell preparations. 相似文献
994.
Gerald M. Rittenberg M.D. Stephen I. Schabel M.D. Ivan Vujic M.D. Hubert C. Meredith M.D. 《Skeletal radiology》1978,2(4):243-244
The angiographic analogue of the sunburst, (right angle) periosteal new bone formation in osteogenic sarcoma is described. The angiographic findings in this tumor and their relationship to the pathologic appearance are discussed. 相似文献
995.
Résumé Les auteurs présentent une série de 30 pseudarthroses fistuleuses de jambe traitées par greffe intertibiopéronière, revues avec un recul allant de 3 à 9 ans.La voie d'abord utilisée pour la greffe est le plus souvent rétropéronière; dans 14 cas l'immobilisation a été réalisée par un plâtre et dans 16 cas par un fixateur externe (chez 9 malades, l'opération a été réalisée après mise en place du fixateur). 28 guérisons sont constatées (25 rapides en 3 à 8 mois, 3 plus lentes) et 2 échecs.Les auteurs insistent sur l'intérêt de la voie rétropéronière qui permet le plus souvent de rester à distance des parties molles «septiques» et du fixateur externe comme moyen de contention.L'indication de cette méthode concerne surtout les pseudarthroses infectées anciennes avec des extrémités osseuses atrophiques ou en cas de perte de substance osseuse. Dans les autres cas, la décortication de Judet est plus simple et permet d'obtenir d'excellents résultats.
Intertibio-peroneal graft in the treatment of infected non-united legs
Summary The authors present a series of 30 cases of fistular non united fractures of the leg treated by interosseous bone graft. Survey was performed from 3 to 9 years.In most cases, the surgical approach is made behind the fibula; in 14 cases, immobilization by means of a plaster cast and in 16 cases by means of external fixation (in 9 cases, external fixation bar + screws was realised first).Healing occured in 28 cases (quick in 25 cases, i.e. within 3–8 months, slow in 3 cases) and 2 failures.The authors emphasize the value of the posterior (retrofibular) approach, which avoids the distal septic soft areas, and of the bar-screws device.The procedure is mostly relevant in old infected non united fractures, with atrophic bony extremities or with boneloss.In the other cases, Judet's procedure is more simple and allows excellent results.相似文献
996.
The validity of the Cognitive Coping Strategy Inventory (CCSI; Butler et al., 1989) was tested in a prospective fashion. Subjects were randomly assigned to one of three conditions. Some were matched to a strategy for which they received a high CCSI score, some were mismatched to a strategy for which they received a low CCSI score, and some were given a choice of strategies. Those subjects using a matched strategy obtained better threshold and tolerance times on the cold pressor than subjects who used a mismatched strategy. Despite clear differences in exposure to the cold pressor these conditions did not differ from each other in self-reported levels of pain. It was concluded that the CCSI appears to be a valid and useful tool for selecting a coping strategy to help particular individuals manage acute pain. Though the CCSI is relatively easy to administer and score, the comparative costs and benefits of using it must be weighed against the somewhat more efficient approach of simply offering the subject a choice of treatments. Subjects given a choice of strategies performed as well as subjects matched to a strategy on the basis of CCSI scores. 相似文献
997.
T. Buhr H. Choritz A. Georgii 《Virchows Archiv : an international journal of pathology》1992,420(6):473-478
Summary A histological study on sequential bone marrow biopsies in patients with chronic myeloid leukaemia (CML) was performed. We wished to answer the question as to whether a different content of megakaryopoiesis in the bone marrow of CML patients has a prognostic significance for the development of myelofibrosis during the course of disease. In addition, the significance of possible changes in the quantity of megakaryopoiesis in this process was assessed. In 186 patients who had no fibre increase at first diagnosis, the rate of subsequent myelofibrosis varied from 19% for the common or granulocytic subtype (CML.CT) to 40% for patients with features of megakaryocytic increase (CML.MI). No significant differences were found either in the rapidity of progression to fibrosis or in the final rate of osteomyelosclerosis. Whereas in CML.MI most patients (75%) showed an increase of fibres only, this was accompanied by an additional increase of megakaryocytes in CML.CT, changing the histological pattern from CML.CT to MI or MP, respectively. The data therefore revealed a correlation between fibre increase and subtyping of CML as suggested by the Hannover classification of chronic myeloproliferative diseases. Subtypes of CML with megakaryocytic increase could be shown to present a pre-myelofibrotic stage of disease and may therefore be conceived as a particular pathway of acceleration. 相似文献
998.
Richard S. Elloway Martin P. Jacobs Milton F. Nathan Joseph C. Mantil 《European journal of nuclear medicine and molecular imaging》1992,19(2):113-118
We combined edrophonium provocative testing with the technique of radionuclide oesophageal transit (RET) in 30 consecutive patients with non-cardiac chest pain (NCCP) and 12 controls. The oesophageal transit time of aqueous technetium-99m sulfur colloid was determined before and after intravenous infusion of 80 g/kg edrophonium chloride (ED). Patient symptoms during provocative RET (P-RET) were recorded. Thirteen (43%) of the patients had abnormal study results, whereas all control subjects had normal results. Three groups considered abnormal were observed: (a) in two patients (6%), the pain was reproduced and transit pre- and post-ED administration was prolonged (>15 s); (b) in six patients (20%), the pain was reproduced, but transit was normal pre- and post-ED; (c) in five patients (17%), transit pre- and post-ED was prolonged, but no pain was reproduced. In five patients (17%), ED prolonged the transit time > 15 s without pain, but the baseline transit was normal. Transit time was measurable in 23 patients. Mean pre-ED transit time was 10.2 ± 7.4 s (mean ± SD) and post-ED, 12.4 ± 8.0 s (P=0.3). We conclude that ED has no significant effect on transit time, and the pain induced by ED rarely correlates with an abnormal transit; P-RET provides additional information to baseline RET, increasing sensitivity, and may be a useful screening method in the evaluation of patients with NCCP. 相似文献
999.
Kumagai Y. Shimoji K. Honma T. Uchiyama S. Ishijima B. Hokari T. Fujioka H. Fukuda S. Ohama E. 《Acta neurochirurgica》1992,115(3-4):71-78
Summary Several clinical problems related to the dorsal root entry zone lesions (DREZLs) in 15 patients with chronic pain are presented and discussed in terms of ratings of pain relief following surgery, development of sensory or motor weakness and postmortem histologies. Subjective pain relief exceeding 70% was achieved at around 2 weeks after the operations in most patients (13/15), and then decreased in some to 30 from 70% in the follow-up observations. Our new objective pain relief score was tested in these patients. A significant positive correlation between subjective pain relief and our objective pain relief scale was found, but some discrepancies between them were also found during the follow-up. Sensory loss, motor weakness, paraesthesia and a new pain were found as complications in 12, 7, 4 and 6 patients, respectively. Postmortem histological findings of the spinal cord in two patients with systemic lupus erythematosus and uterine cancer, who received bilateral DREZLs twice and bilateral DREZLs plus commissural myelotomy, respectively, indicate that care should be taken to avoid extension of the coagulation beyond the dorsal horn. 相似文献
1000.
Jeri W. Nieves Felicia Cosman Chris Mars Robert Lindsay 《Calcified tissue international》1992,51(5):352-355
Summary Forearm bone mineral density (BMD) was measured at proximal and distal sites by 125I single photon absorptiometry (SPA) and by dual energy X-ray absorptiometry (DXA) in 67 consecutive subjects, aged 18–75 years. Correlations and regression equations between these two techniques were determined. All forearm measurements were significantly correlated with each other (r=0.599–0.926; P0.0001). Although SPA and DXA correct for fat in different ways, we found similar correlation and regression equations in women with body mass index measurements above and below the mean. In addition, forearm measurements by both techniques were moderately correlated with vertebral spine and hip BMD. We conclude that overall, SPA forearm measurements in a population can be calibrated to DXA measurements if necessary, and that DXA forearm measurements are as predictive of the remainder of the skeleton as SPA measurements. 相似文献