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Angelo Cagnacci Gian Benedetto Melis Renza Soldani Anna Maria Paoletti Marco Gambacciani Adriana Spinetti Piero Fioretti 《Maturitas》1991,13(4):283-296
The neuroendocrine and clinical effects of transdermal 17β-estradiol (rated at 50 μg/day; TTS 50) were studied in 40 postmenopausal women; ten additional postmenopausal women did not receive any drugs. The changes in LH and rectal temperature induced by the infusion of the opioid antagonist naloxone (10 mg i.v. bolus plus 10 mg/h for 4 h) were used to evaluate the central activity of endogenous opioid peptides. TTS 50 increased opioid activity, as evidenced by the restoration of the LH response (P < 0.01) and the enhancement of the hypothermic effect (P < 0.05) of naloxone. A greater reduction in hot flushes was observed in TTS 50-treated subjects than in untreated women, with the maximal effect of TTS 50 achieved after 3 months of therapy. TTS 50 did not modify the concentrations of circulating lipids, glucose or liver enzymes but reduced the biochemical parameters indicative of bone reabsorption. Bone density of the distal radius significantly increased during TTS 50 (P < 0.02), reaching its maximum value after 6 months of therapy. Thereafter bone density declined, but more slowly than in untreated women.
Our data suggest that TTS 50 has marked neuroendocrine effects, that it diminishes the incidence of hot flushes and reduces bone demineralization. By contrast, it has a very little, if any, metabolic impact on the liver or on glucose and lipid metabolism. 相似文献
3.
Khai Lai Monica Rencken Barbara L. Drinkwater Charles H. Chesnut III 《Calcified tissue international》1993,53(4):225-228
Summary The purpose of this study was to determine whether bone mineral density (BMD) measurements at the lumbar spine and femoral neck provided comparable information to women planning to use that knowledge to help them make a decision about hormone replacement therapy. Eighty-eight healthy Caucasian women, aged 44–59 and within 0 to 5 years of menopause, participated in the study. BMD measurements were performed at the lumbar spine (L1-L4) and the femoral neck by dual energy X-ray absorptiometry (DXA). Criteria suggested by the National Osteoporosis Foundation were used to categorize women as at risk for osteoporosis, bone density more than one standard deviation (SD) below the young adult mean, or as low risk, bone density at or above this level. The re that 46 women would be classified into the low risk category on the basis of spinal BMD alone. However, 28 of these 46 women would fall into the at risk category when the femoral neck BMD was measured. Sixty-one percent of women informed they were at low risk on the basis of spinal BMD would be considered at risk based on femoral neck BMD. When femoral neck BMD was used as the primary risk indicator, 14% of the women classified as low risk would be at risk if spinal BMD were added. These results suggest that both lumbar spine and proximal femur measurements should be made when women are using bone density measurements as an aid in deciding whether or not to use hormone therapy in their postmenopausal years. 相似文献
4.
Cyrus Cooper 《Calcified tissue international》1993,53(Z1):S23-S26
Fragility fractures, particularly those of the hip, vertebrae, and distal forearm, constitute a major public health problem. The two ultimate determinants of fracture are bone strength and propensity to trauma. Bone strength depends not only upon bone mass but also upon a variety of qualitative aspects of bone structure. These include its architecture, the amount of fatigue damage it has sustained, and changes in its bulk material properties, indices that are collectively subsumed into the term bone quality Fragility fractures show differences in their patterns of incidence by age, sex, ethnic group, geographic area, and season. Many of these differences are currently unexplained, and disorders of bone quality might contribute to them. There are two fracture sites at which evidence implicates bone quality more directly—the spine and proximal femur. Many vertebral compression fractures follow minimal trauma, and controlled studies suggest that vertebral microarchitecture contributes to fracture risk independently of vertebral bone mass. At the hip, observational studies have pointed to a role for disordered trabecular architecture, accumulation of microfractures (fatigue damage), and the accumulation of osteoid. The extent to which these phenomena act independently of bone mass, however, remains uncertain.Presented at the NIA Workshop on Aging and Bone Quality, September 3–4, 1992, Bethesda, Maryland 相似文献
5.
Determination of the concentration of osteocalcin in rat serum is frequently performed using a commercially available radioimmunoassay
(RIA). However, this assay takes 3 days to complete, uses radioactive material, and has a narrow linear range. The limited
range of the RIA makes it necessary to test multiple dilutions of the sample which frequently results in values that differ,
depending on the dilution. In order to overcome these limitations, we have developed an ELISA that utilizes the same standards
and anti-rat osteocalcin antiserum, as is used in the RIA. The principle of the ELISA is that the osteocalcin in the sample
competes with osteocalcin previously immobilized on a microtiter plate to bind to the available anti-rat osteocalcin antibodies.
The amount of antibody bound to the immobilized osteocalcin is determined colorimetrically using a secondary antibody coupled
to alkaline phosphatase. This ELISA has a three-log linear response with a sensitivity of 0.1–0.15 ng/ml and intra- and interassay
coefficient of variance (CV) values of less than 10%. Most importantly, the assay is rapid and only requires a 2-hour incubation
of the sample with the antiserum. The incubation time is important since we and others have observed a significant decrease
in the osteocalcin level from serum samples incubated for long periods of time with the antiserum, presumably due to degradation
of the osteocalcin. In general, the commercially available RIA gives osteocalcin values that are one-half to one-fourth that
of the ELISA because the RIA requires a 48-hour incubation time.
Received: 14 November 1997 / Accepted: 9 July 1998 相似文献
6.
Dott M. Varenna L. Sinigaglia L. Binelli P. Beltrametti M. Gallazzi 《Clinical rheumatology》1996,15(2):169-173
Summary Three new cases of transient osteoporosis of the hip are reported. Diagnosis was achieved by plain radiographs, bone scintiscan, magnetic resonance imaging and X-ray absorptiometry of proximal femurs. The densitometry showed at the Ward's triangle a mean reduction of bone mineral density in the affected side of 36%. All subjects were treated with i.v. clodronate for ten consecutive days with a complete recovery of femoral density within 4 months. X-ray absorptiometry allows a quantification of the demineralization process and can be useful in the long term evaluation of this entity. 相似文献
7.
Relative risk factors for osteoporotic fracture: A pilot study of the MEDOS questionnaire 总被引:3,自引:0,他引:3
Summary This study tested selected elements of a questionnaire devised to detect risk factors for osteoporosis in a large case-control study of hip fracture. The questions were applied to two separate studies. The first utilised a hospital sample of postmenopausal women with established vertebral osteoporosis, and responses were compared to woman with primary osteoarthritis. In a second study, the questionnaire was applied to apparently healthy women participating in a study of bone density. Significant differences between patients with osteoporosis and osteoarthritis were observed in body mass index, the prevalence of appendicular fractures, the degree of immobilisation, the age of menarche, exposure to sunlight and indices of physical activity. Significant differences were found in bone mass in healthy women divided according to the age of menarche, parity and duration of lactation. These data identify previously established risk factors for osteoporosis and suggest that the MEDOS questionnaire will provide a powerful tool for the future assessment of risk factors in osteoporosis.
Collaborating centers: Dilen G., Istanbul; Gennari C., Siena; Lopez Vaz A.A., Porto; Lyritis G., Athens; Mazzuoli G.D., Rome; Miravet L., Paris; Passeri M., Parma; Perez Cano R., Sevilla; Rapado A., Madrid; Ribot C., Toulouse.
Project group: Allander E., WHO Collaborating Centre for the Epidemiology of Rheumatic Conditions, Huddinge; Dequeker J., WHO Consultant, Leuven; Gonzalez A., Sandoz, Basle; Kanis J.A., European Osteoporosis Foundation, Sheffield; Keen D., Sandoz, Basle; Khaltaev N., WHO Non-communicable Diseases, Geneva; Plüss M., Sandoz, Basle. 相似文献
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周大勇 《中国现代药物应用》2011,5(21):117-119
目的探讨辛伐他汀治疗骨质疏松症的相关研究。方法查阅国内文献,总结辛伐他汀对各类骨质疏松症的影响。结果辛伐他汀能增加骨密度,提高骨钙素水平,促进新骨形成。结论辛伐他汀治疗骨质疏松症需要更多的临床研究。 相似文献