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161.
Associations between body morphology and bone mineral density in premenopausal women 总被引:1,自引:0,他引:1
To investigate whether body morphology, obesity and its long time evolution were associated with lumbar and femoral bone mineral density (BMD) in premenopausal women of the same age. Design: Cross-sectional study. Subjects: 72 healthy premenopausal women born in 1950 (42 years) with a regular physical activity. Measurements: BMD measured by dual-X-ray absorptiometry (DEXA) at lumbar spine and proximal femur; body weight, body mass index (BMI), BMI at 20 years (BMI-20), increase in BMI since age of 20 (BMI->20), body circumferences (breast, waist, hip) and their ratios (WHR, BHR, WBR), smoking and alcohol intake. Results: Lumbar spine BMD did not correlate with any anthropometric measurement. Femoral BMDs correlated positively with weight, BMI, BMI-20, breast, waist, WHR and BHR. The BMI-20 explained the 5% and the current BMI the 13% of variance of total femur BMD. After adjustment for weight or BMI, breast circumference and BHR remained significantly correlated with all femoral BMDs sites except neck. Weight was the best predictor for neck BMD (R2 = 0.08; p < 0.02), and BHR for Ward's triangle (R2 = 0.12; p < 0.01) and trochanter (R2 = 0.10; p < 0.001). Alcohol intake, cigarette smoking, and age of menarche were not related to BMDs. Conclusion: In premenopausal women of the same age, lumbar spine BMD was not associated with any anthropometric measurement. Greater BHR and its long time of evolution may be determinants of greater femoral BMD (trabecular), whereas body weight may be determinant of femoral neck BMD (cortical). Further studies are needed to determine whether large breast to hip ratio may be considered as a protective factor for femoral osteoporosis. 相似文献
162.
Edward W. Lipkin M.D. Ph.D. Susan M. Ott Gordon L. Klein Leonard J. Deftos 《Calcified tissue international》1990,47(2):75-81
Summary Bone gamma-carboxyglutamic acid containing protein (BGP) has been utilized effectively as a serum marker of bone turnover
in healthy normals and in individuals with a variety of metabolic bone disorders including postmenopausal osteoporosis and
Paget's disease. The utility of this serum marker in other bone disorders, including that associated with the maintenance
of patients on long-term parenteral nutrition, still requires definition. Because of our interest in this clinical syndrome
and the availability of serum and of bone formation rates (BFR) measured directly from double tetracycline labeling in 11
long-term parenteral nutrition patients, we measured BGP levels in these patients and attempted to correlate this measure
with BFR. Serum vitamin D metabolites, immunoreactive parathyroid hormone (PTH), and alkaline phosphatase (alk phos) were
also measured. Serum BGP was only weakly and not significantly correlated (r=0.24, p=NS) with bone formation rate for the
group as a whole. However, in a subgroup of 10 patients without hyperparathyroidism, there was strong and significant correlation
(r=0.81,P<0.01) between BGP and BFR. There was also a strong correlation between bone formation rate and serum 1,25 dihydroxyvitamin
D [1,25(OH)2D] levels (r=0.89,P<0.01, n=11). The mechanism of this association could not be established. A correlation of borderline significance was observed
between bone formation rate and serum alk phos (r=0.60,P=0.05, n=11). The current data suggest that additional studies may help to more fully define the utility of serum measurements
in quantifying bone dynamics in parenteral nutrition patients, and that measures of vitamin D metabolites, BGP, and alk phos
may prove useful. 相似文献
163.
It is well known that certain connective tissue cells (viz., dermal fibroblasts) can express the gene for a muscle actin--alpha-smooth muscle actin--and can contract. This process contributes to skin wound closure and is responsible for Dupuytren's contracture. The objective of this study was to determine if human osteoblasts can also express the gene for alpha-smooth muscle actin. Immunohistochemistry using a monoclonal antibody for alpha-smooth muscle actin was performed on human cancellous bone samples obtained from 20 individuals at the time of total joint arthroplasty. The percentages of resting and active osteoblasts on the bone surfaces containing this muscle actin isoform were evaluated. Explants of human bone were also studied for the expression of alpha-smooth muscle actin in the tissue and in the outgrowing cells with time in culture. Western blot analysis was performed to quantify the alpha-smooth muscle actin content of the outgrowing cells relative to smooth muscle cell controls. Nine +/- 2% (mean +/- SEM; n = 20) of the cells classified as inactive osteoblasts and 69 +/- 3% (n = 19) of the cells identified as active osteoblasts on the bone surface contained alpha-smooth muscle actin. This difference was highly statistically significant (Student's t test, p < 0.0001). Similar profiles of alpha-smooth muscle actin-expressing cells were found in explants cultured for up to 12 weeks. Cells forming a layer on the surface of the explants and growing out from them in monolayer also contained alpha-smooth muscle actin by immunohistochemistry and Western blot analysis. Human osteoblasts can express the gene for alpha-smooth muscle actin. This expression should be considered a phenotypic characteristic of this cell type, conferred by its progenitor cells: bone marrow stromal-derived stem cells, and perhaps pericytes and smooth muscle cells. 相似文献
164.
Cyst-like lesions in the radius and tibia were observed in two children as a post-fracture event. The pathogenesis of these lesions is discussed. Cut sections from anatomic specimens display extensive hemorrhage in subperiosteal as well as endosteal and trabecular bone. Cysts arising from hemorrhagic resorption in various locales may explain the occasional atypical appearance of these lesions. 相似文献
165.
目的探讨成神经细胞瘤骨转移的X线表现及分型。方法分析13例成神经细胞瘤骨转移的X线表现,并根据X线表现将其分为溶骨型和成骨型。结果13例患者中,溶骨型9例,成骨型4例,各型病例均有其特征性的X线表现。结论根据患者年龄及特征性的X线表现,对成神经细胞瘤骨转移可作出诊断。 相似文献
166.
167.
肩关节脱位手法整复的流派及发展动态 总被引:8,自引:6,他引:2
肩关节脱位指的是肩肱(或称盂肱)关节脱位,临床上十分常见,肩关节脱位通常采取手法整复,疗效确切,手法整复研究也较多,笔者参阅有关文献资料,结合自己的临床体会,对国内肩关节脱位的手法整复流派和发展动态做一整理,与同仁共飨。 相似文献
168.
Disc replacement using Pro-Disc C versus fusion: a prospective randomised and controlled radiographic and clinical study 总被引:4,自引:0,他引:4
A. Nabhan F. Ahlhelm T. Pitzen W. I. Steudel J. Jung K. Shariat O. Steimer F. Bachelier D. Pape 《European spine journal》2007,16(3):423-430
Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative
disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent
segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc
prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to
judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial
disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to
the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation
were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage
with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately
as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination.
Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental
motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant
pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery.
The clinical results are the same when compared to the early results following ACDF. 相似文献
169.
双支撑骨柱移植术治疗股骨头坏死的远期疗效分析 总被引:6,自引:1,他引:5
目的分析双支撑骨柱移植术治疗股骨头坏死的远期疗效。方法从1988年3月以来,采用双支撑骨柱移植术治疗成人股骨头坏死366例466髋,获5年以上随访者186例206髋,平均年龄32.2(20~60)岁。按病因分类:激素性者60例68髋,酒精性者86例96髋,激素加酒精者30例32髋,外伤性者10例10髋。ARCOⅡB、ⅡC、ⅢA、ⅢB、ⅢC、Ⅳ期患者分别为36、30、40、40、32、28髋。参照百分法进行疗效评价。结果术后所有患者的髋关节疼痛均获得明显缓解或消失,股骨头高度有不同程度增加,关节活动度有改善。平均随访时间10.5(5~16)年,手术前与随访时临床评价(疼痛、功能、关节活动度)、X线评价、总分数比较,差异均有统计学意义(P<0.01)。结果显示ⅡB~Ⅳ期优良率分别为83.3%、80.0%、75.0%、65.0%、40.6%、28.6%,总优良率为63.6%。Ⅱ期效果好(81.8%),Ⅲ期早期(ⅢA、ⅢB)效果较好(70%),ⅢC、Ⅳ期者效果差(35%)。期别间疗效依次降低,差异有统计学意义(P=0.0001)。30岁以内患者术后股骨头内植骨愈合较快,平均为3.2(2.9~3.5)个月。50~60岁患者植骨愈合需时较长,平均为5.5(4.4~6.4)个月。结论该术式治疗股骨头坏死的远期疗效良好,治疗效果与股骨头坏死期别有关,尤其适用于股骨头坏死Ⅱ期和Ⅲ期的早期病例。 相似文献
170.
Aromatization of androgens is important for skeletal maintenance of aged male rats 总被引:16,自引:0,他引:16
D. Vanderschueren E. Van Herck R. De Coster R. Bouillon 《Calcified tissue international》1996,59(3):179-183
A nonsteroidal aromatase inhibitor vorozole (VOR) was administered to aged (12 months old) male Wistar rats and its effect
was compared with the effect of androgen deficiency. The rats were either sham-operated (SHAM) or orchidectomized (ORCH) and
treated with or without VOR. Thus, four experimental groups were created (SHAM, ORCH, SHAM + VOR, ORCH + VOR). The follow-up
period was 4 months. At the end of the experimental period, bone mineral density (BMD) of the first four lumbar vertebrae
and right femur was measured ex vivo with dual-energy X-ray absorptiometry, bone formation was evaluated by serum osteocalcin, and bone resorption by urinary excretion
of (deoxy)pyridinoline. Orchidectomy increased bone resorption 2- to 3-fold whereas bone formation was only slightly increased.
Treatment of intact male rats with VOR also increased bone resorption (+30% increase) whereas bone formation was not increased
in this SHAM + VOR group. Their BMD was 7% lower in the femur (P < 0.01) and 6% lower in the lumbar vertebrae (P < 0.01) compared with the SHAM group that had not received VOR. Moreover, this decrease of bone mineral density was not significantly
different from the expected decrease of bone density observed in the ORCH groups (6–10%). This was also reflected by a decrease
of calcium content of the first four lumbar vertebrae of 15% (P < 0.001) in the SHAM + VOR group and 9–14% (P < 0.05) in the ORCH groups compared with the SHAM group, respectively. These data therefore suggest that inhibition of aromatization
of androgens into estrogens increases bone resorption and bone loss similar to that observed after complete removal of androgens.
Aromatization of androgens into estrogens may therefore, at least partly, explain the effects of androgens on skeletal maintenance.
Received: 13 October 1995 / Accepted: 23 February 1996 相似文献