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1.
目的采集手术切除未经培养的骨肉瘤标本,研究肿瘤中成骨细胞的分化及其与临床因素的关系。方法观察骨肉瘤中成骨细胞相关基因表达的频率、特异性,以及骨肉瘤成骨细胞表型与生物学行为的关系。应用RT-PCR方法研究48例骨肉瘤标本的碱性磷酸酶(ALP)、骨钙素(OC)和骨桥蛋白(ON)的mRNA转录。磷酸甘油酸激酶(PGK)被用于内参照。结果在大多数骨肉瘤标本中可以发现ALP或OC的mRNA转录(分别为93.75%,79.17%)。在所有的肉瘤检测中均可发现ON的mRNA转录。在骨肉瘤的成骨细胞亚型中可见到ALP和OC的高水平表达。肺转移瘤OC的mRNA表达弱于原发灶。肿瘤细胞有高水平OC表达的病例组有较高的生存率(P=0.045)。结论OC是目前最好的成骨细胞特异性标记物,将来可能用于检测骨肉瘤患者外周血中循环的肿瘤细胞。  相似文献   
2.
目的:建立骨钙素酶免疫测定方法,并应用于临床检测血清骨钙素。方法:应用了3种检测模式,根据检测灵敏度、剂量反应曲线的形态进行分析,选择出合适的模式进一步应用于临床血清标本的骨钙素检测。结果:所采用的骨钙素单克隆抗体是钙离子依赖型的。固相抗原竞争法适合于临床定量测定骨钙素。最低可测限为1.4μg/L;20μg/L骨钙素样品批内CV=3.98%,批间CV=12.67%。测定正常献血员140名(年龄17-45岁),第5-95百分位点的骨钙素含量,男性为7.5-15.0μg/L女性为7.0-17.5μg/L。70例疑有骨质疏松症患者血清骨钙素含量2.91-30.20μg/L,以第95百分位点的骨钙素含量为cut-off值,升高5例。与进口试剂盒(Novocalcin,USA)相比较,有较好的相关性,r=0.81。结论:固相抗原竞争法酶免疫测定可以灵敏地检测血清中骨钙素含量,有实用价值。  相似文献   
3.
Bone scintigraphy plays a major role in the diagnosis of bone metastases. The clinical utility of new biochemical markers of bone metabolism has recently been investigated in various bone diseases. This study evaluated the role of some bone metabolism markers in comparison with bone scan in the follow-up of breast cancer patients. We studied 149 patients with breast cancer, 33 (22%) of whom had bone metastases. IRMAs were used for the evaluation of blood levels of osteocalcin, bone alkaline phosphatase (BAP), the C-terminal propeptide of type I procollagen and the C-terminal cross-linked telopeptide of type I collagen (ICTP). Multivariate regression analysis showed that menopausal status (P=0.007) and metastatic bone lesions (P=0.001) affected bone marker levels. When considering post-menopausal women, the only subset in which bone metabolism marker behaviour could be reliably investigated, we found a high degree of overlap in marker distribution for scan-positive and scan-negative patients. Discrimination between scan-negative and scan-positive patients based on the above markers, taken singly or jointly, was assessed by means of logistic discriminant analysis. The best discrimination was achieved with BAP, closely followed by ICTP. BAP and ICTP together gave a slight improvement over the use of the two markers separately. However, even in this case the degree of discrimination was poor and its clinical utility was limited. In fact, to achieve a specificity of 95%, the sensitivity of the test was about 20%; conversely, with a sensitivity of 95%, the specificity was below 10%. In conclusion, based on our findings, we believe that blood levels of the investigated markers cannot replace bone scintigraphy in the follow-up of breast cancer patients for the early detection of bone metastases. Received 14 April and in revised form 5 July 1997  相似文献   
4.
Summary Since it has been suggested that gastric resections are followed by changes in bone metabolism, the aim of our study was to determine the biochemical parameters of bone metabolism and radial and lumbar bone density in 15 male ulcus patients treated by partial gastrectomy (Billroth II). Comparing the data with those of a corresponding control group, the lumbar bone density measured by quantitative computed tomography was statistically significantly lower (P < 0.04) in the patient group, whereas the peripheral bone mass of the distal part of the nondominant forearm measured by single-photon absorptiometry showed no statistically significant difference. In addition, a marked increase in alkaline phosphatase (P < 0.002) and urinary excretion of hydroxyproline (P < 0.003) was found in the gastrectomy group, whereas the 25-hydroxy-vitamin D levels were found to be significantly decreased (P < 0.04). Osteocalcin, a biochemical marker for osteoblast activity, and the carboxy-terminal propeptide of type I procollagen (PICP), a marker of collagen formation, were slightly but not significantly higher in gastrectomy-treated patients. The serum parathyroid hormone levels were similar in both groups. As none of the patients had any radiologic evidence of osteopenia, the changes in biochemical parameters of bone metabolism and bone mass in patients who had undergone partial gastrectomy could be a marker of latent bone loss.Abbreviations DPA/SPA dual/single-photon absorptiometry - BMD bone mineral density - QCT quantitative computed tomography - PICP carboxy-terminal propeptide of type I procollagen - 250HD3 25-hydroxy-vitamin D - iPTH parathyroid hormone - OC osteocalcin - BMC bone mineral content  相似文献   
5.
目的 探讨长期应用糖皮质激素 (GC)治疗对肾小球疾病患者骨代谢影响的因素。方法  2 0 7例肾小球疾病患者 ,应用常规剂量GC治疗 ,于治疗前及治疗后每隔 3~ 6个月 ,进行了 35 7例次腰椎和股骨近端骨密度 (BMD)、血钙、血磷和骨钙素浓度测定。结果 ①用GC后骨钙素浓度明显降低 (P均 <0 0 0 5 ) ,但其不能预测BMD下降。②用药 15个月后男性各部位BMD均减少 (32 2~111 5 )mg/cm2 ,以L1 4和股骨粗隆更明显 (P均 <0 0 5 ) ,骨丢失率 3 3%~ 10 3% ;女性L1 4BMD均减少(4 3 8~ 76 0 )mg/cm2 ,以L1更明显 (P <0 0 5 ) ,骨丢失率 3 9%~ 7 9%。③年龄与各部位BMD变化呈负相关 ,但不影响GC造成的骨丢失。男性各部位、女性L1 4BMD减少与GC累计剂量和GC用药时间负相关。④用GC15个月 (GC累计剂量 10g以上 ) ,男性L1 4BMD正常的比例从 3/ 4至 3/ 5 ;女性L1和L2 BMD正常者从 3/ 4减少到 1/ 2。结论 长期口服糖皮激素导致与剂量和用药时间相关的腰椎和男性股骨粗隆骨丢失 ,年龄偏大和男性患者骨丢失更明显。  相似文献   
6.
目的观察低强度激光照射对兔实验性牙齿移动牙槽骨组织中骨钙素水平变化的影响。方法30只雄性大耳白兔,随机分为1、3、5、7、14和21d组,共6组,每组5只。在兔左右上颌第一磨牙与上颌切牙之间放置不锈钢闭合螺旋弹簧,牵引第一、二磨牙向近中移动。右侧为实验侧,以2.5J/cm2的He-Ne激光和514J/cm2的CO2激光同时照射。左侧为对照侧,不照射激光。拔除上颌第一磨牙,分别取其近、远中牙槽骨组织(根上2/3处),以放射免疫法检测牙槽骨组织中的骨钙素含量。结果低强度激光照射侧张力区骨钙素含量在施力1、3、5d组高于对照侧(P<0.05);压力区骨钙素含量以施力7d组最高,3、5d组照射侧骨钙素含量低于对照侧(P<0.05)。结论骨钙素在实验性正畸牙齿移动过程中参与了破骨与成骨活动,低强度激光照射可影响正畸牙周组织中骨钙素水平的变化,对正畸牙周组织的骨改建有促进作用。  相似文献   
7.
Summary Algodystrophy (AD) attacks all tissues in the affected region and results in the rapid demineralization of bones. Osteocalcin (OC) and alkaline phosphatase (AP) are markers of bone turnover. Calcitonin is the treatment of choice of AD. Two groups of patients were studied: Group I (n=8)-acute stage of AD (before and during the calcitonin treatment), Group II (n=5)-late chronic stage of AD. In the acute stage of AD both OC level and AP activity were increased. They were normal in the chronic state of AD. During the calcitonin treatment OC level normalized after 14 days and then increased again. During the treatment, AP activity temporarily increased and then returned to the initial level. We confirm that an increased bone turnover is observed in the acute stage of AD. Discrepancy between OC level and AP activity reflects the local metabolic disturbances. Salmon calcitonin inhibits the algodystrophic process and probably contributes to the activation of the skeletal restoration.  相似文献   
8.
目的 为阐明孕妇和胎儿骨钙素 (osteoblastic)代谢规律 ,对各孕周期妇女外周血和胎儿脐带血骨钙素水平的动态变化进行研究。方法 采用荧光酶联免疫法对 14 2例孕妇、2 2例产妇及 34例不同孕龄胎儿的脐带血骨钙素水平进行检测。结果孕妇血清骨钙素随妊娠发展逐渐下降 ,至孕中期最低 (3.3± 1.4 6 ) μg/L ,随后又逐渐升高。分娩即刻产妇血清骨钙素 (12 .81± 4 .2 8) μg/L显著高于妊娠各阶段的水平 (P <0 .0 1) ,产后数日即显著下降至接近妊娠前的基线水平。脐带血骨钙素水平在孕中期最低 (0 .88± 0 .39) μg/L ,随后则升高 ,并且自孕 2 4w起保持于接近母体血清骨钙素水平。结论这段妊娠期是胎儿骨钙积累活跃的阶段 ,这种恒定的骨钙素水平对胎儿骨骼系统的正常发育 ,可能具有重要意义  相似文献   
9.
The mechanisms underlying glucocorticoid-induced osteoporosis in humans are a defect in bone formation associated with increased bone resorption. The latter may be due to elevated parathyroid hormone (PTH) levels induced by the impairment of intestinal calcium absorption caused by corticosteroids. In this study we analysed the effects of corticosteroids in old ewes, a potential model for the study of human bone turnover. Two groups of seven 9-year-old female sheep were selected. The first group was injected intramuscularly with a daily dose of 30 mg methylprednisone (MP) during the first 2 months and 15 mg during the last month. After 2 and 3 months of treatment, blood samples were taken. At the end of the experiment the animals were slaughtered and the iliac crest kept for bone histomorphometry. Serum osteocalcin (sOC) rapidly and markedly decreased in the MP-treated group compared with controls (–77%;p<0.01). In contrast, at the end of the experiment serum calcium and PTH levels were similar in both groups. Histomorphometric analysis showed a significant reduction in the wall width of trabecular packets. Dynamic parameters reflecting bone formation at the tissue and cell levels were significantly lower in the MP-treated group than in controls, with a highly significant decrease in the mineralization rate (MAR: –63%,p<0.05) and double-labeled perimeter (dLPm/B.Pm: –92%p<0.05). The bone formation rate (BFR/B.Pm) also decreased by 84% and the adjusted apposition rate (Aj.AR) by 80%. The increase in the total formation period was mainly due to an increase in the inactive period. Significant correlations were found between sOC and MAR, dLPm/B.Pm and BFR/B.Pm (withr respectively 0.67, 0.76 and 0.51). In conclusion, the effects of corticosteroid on ewe bone remodeling are essentially characterized by a major bone formation defect without evidence of secondary hyperparathyroidism, although this cannot be totally excluded by our results. Ewes treated with glucocorticoids could represent a good model for evaluating the effects of drugs candidates for all bone conditions characterized by reduced bone formation resulting from osteoblastic depression.  相似文献   
10.
The purpose of this study was to estimate clinical validity of a new available immunoradiometric assay for circulating intact human BGP (N-tact Osteo SP) by measuring this protein in a large number of normal subjects and patients with the most common metabolic bone diseases. One hundred normal subjects were studied in order to obtain our normal ranges (4.9 ± 1.7 ng/ml). The mean values found in 28 patients with primary hyperparathyroidism (17.5 ± 22.8 ng/ml, P < 0.001), 15 glucocorticoid-treated patients (1.9 ± 1.5, P < 0.001), 10 patients with hypoparathyroidism (1.5 ± 0.7, P < 0.001), 9 with hyperthyroidism (8.3 ± 3.8, P < 0.001), 8 with skeletal metastases (7.2 ± 2.3, P < 0.001), and 4 with humoral hypercalcemia of malignancy (2.42 ± 1.91, P < 0.005) were significantly different from mean values found in normal subjects. Mean decrease of serum osteocalcin T-score values was significantly greater when evaluated by N-tact Osteo SP assay in 15 steroid-treated patients (−1.4 ± 1.0) and 19 primary hyperparathyroid (PHPT) patients (3.6 ± 1.9), compared with the mean values obtained with the Elsa-Osteo assay (−0.67 ± 1.2, P < 0.002 and 4.3 ± 2.8, P < 0.04, respectively). We found significant correlations between the global skeletal uptake of 99mTc-methylendiphosphonate and serum BGP levels assayed by both N-tact Osteo SP (P < 0.01) and Elsa-Ost-Nat assay (P < 0.05). Our results indicate that this new immunoradiometric assay for the intact human osteocalcin has the potential for good discrimination between normal subjects and patients with both low and high bone turnover. Furthermore, our findings emphasize the fact that, in the absence of available standardized commercial assays, one should rely on only one assay because different results are obtained by different assays under different clinical conditions. Received: 22 January / Accepted: 22 September 1998  相似文献   
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