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排序方式: 共有1371条查询结果,搜索用时 15 毫秒
51.
目的 建立糖尿病大鼠动物模型,观察使用二甲双胍和辛伐他汀对胫骨骨密度的影响,为临床糖尿病患者种植体修复、正畸治疗提供理论依据.方法 采用空腹一次性注射STZ溶液(40 mg/kg),注射STZ 3天后,大鼠空腹血糖高于16.7 mmol,尿糖(+++),视为糖尿病大鼠模型建立成功.建模后,分正常组,模型组,二甲双胍组,二甲双胍和辛伐他汀联用组,检测胫骨骨密度.结果 糖尿病大鼠胫骨骨密度低于二甲双胍组低于二甲双胍和辛伐他汀联用组低于正常组(P<0.01).结论 糖尿病状态下胫骨骨密度低于正常,经过治疗后骨密度改善明显,联用组优于单独使用二甲双胍组. 相似文献
52.
目的 通过测定269名岳阳地区50岁以上人群血清25经维生素D(25(OH)D)和骨密度(BMD)水平,分析岳阳地区50岁以上人群的维生素D ( VitD)状况,并探讨其与BMD的关系。方法 采集受试者的血清后,用电化学发光法测定血清25(OH)D水平,并同时应用双能X线吸收仪测定腰椎及髓部BMD。结果 所有受试者中,VitD严重缺乏者占24. 2 %,缺乏者占45. 0%,不足者占24. 5 %,充足者占6. 3。男、女性受试者的25(OH)D水平、腰椎及髓部的BMD间有统计学差异(P<0.001),男性高于女性。男性各年龄段间25(OH)D水平及各部位BMD无统计学差异(P=0. 101 ,P = 0. 261 ,0. 055 ,0. 170 ,0. 108 ,0. 051 ) ;女性各年龄段之间25(OH)D水平及腰椎BMD无统计学差异(P = 0. 364 , 0. 063 ) ;髓部BMD有统计学差异(P < 0. 001 ),随着年龄的增长而逐步减低。男性受试者中,不同25(OH)D水平组间股骨颈、转子间区及整髓BMD无统计学差异(P = 0. 076 , 0. 425 , 0. 122 );腰椎、大转子区BMD水平间有统计学差异(P=0. 027 , 0. 017 ) , VitD充足组腰椎BMD高于其他各组(P = 0. 005 , 0. 025 , 0. 009 );不足组、严重缺乏组大转子区BMD高于缺乏组(P = 0. 021, 0. 005 )。女性受试者中,不同25(OH)D水平组各部位BMD均无统计学差异(P = 0. 616 , 0. 739 , 0. 559 ; 0. 608 , 0. 641)。结论 在湖南岳阳地区50岁以上人群存在严重的维生素D缺乏及不足;对于维生素D状况与骨密度之间可能无直接关联,需加大样本量进一步观察。 相似文献
53.
Anne Tsampalieros Pooja Gupta Michelle R Denburg Justine Shults Babette S Zemel Sogol Mostoufi‐Moab Rachel J Wetzsteon Rita M Herskovitz Krista M Whitehead Mary B Leonard 《Journal of bone and mineral research》2013,28(3):480-488
The impact of glucocorticoids (GC) on skeletal development has not been established. The objective of this study was to examine changes in volumetric bone mineral density (vBMD) and cortical structure over 1 year in childhood nephrotic syndrome (NS) and to identify associations with concurrent GC exposure and growth. Fifty‐six NS participants, aged 5 to 21 years, were enrolled a median of 4.3 (0.5 to 8.1) years after diagnosis. Tibia peripheral quantitative computed tomography (pQCT) scans were obtained at enrollment and 6 and 12 months later. Sex, race, and age‐specific Z‐scores were generated for trabecular vBMD (TrabBMD‐Z), cortical vBMD (CortBMD‐Z), and cortical area (CortArea‐Z) based on >650 reference participants. CortArea‐Z was further adjusted for tibia length‐for‐age Z‐score. Quasi‐least squares regression was used to identify determinants of changes in pQCT Z‐scores. At enrollment, mean TrabBMD‐Z (?0.54 ± 1.32) was significantly lower (p = 0.0001) and CortBMD‐Z (0.73 ± 1.16, p < 0.0001) and CortArea‐Z (0.27 ± 0.91, p = 0.03) significantly greater in NS versus reference participants, as previously described. Forty‐eight (86%) participants were treated with GC over the study interval (median dose 0.29 mg/kg/day). On average, TrabBMD‐Z and CortBMD‐Z did not change significantly over the study interval; however, CortArea‐Z decreased (p = 0.003). Greater GC dose (p < 0.001), lesser increases in tibia length (p < 0.001), and lesser increases in CortArea‐Z (p = 0.003) were independently associated with greater increases in CortBMD‐Z. Greater increases in tibia length were associated with greater declines in CortArea‐Z (p < 0.01); this association was absent in reference participants (interaction p < 0.02). In conclusion, GC therapy was associated with increases in CortBMD‐Z, potentially related to suppressed bone formation and greater secondary mineralization. Conversely, greater growth and expansion of CortArea‐Z (ie, new bone formation) were associated with declines in CortBMD‐Z. Greater linear growth was associated with impaired expansion of cortical area in NS. Studies are needed to determine the fracture implications of these findings. © 2013 American Society for Bone and Mineral Research. 相似文献
54.
The long-term impact on bone health of lifelong HIV infection and prolonged ART in growing and developing children is not yet known. Measures of bone health in youth must be interpreted in the context of expected developmental and physiologic changes in bone mass, size, density and strength that occur from fetal through adult life. Low bone mineral density (BMD) appears to be common in perinatally HIV-infected youth, especially outside of high-income settings, but data are limited and interpretation complicated by the need for better pediatric norms. The potential negative effects of tenofovir on BMD and bone mass accrual are of particular concern as this drug may be used more widely in younger children. Emphasizing good nutrition, calcium and vitamin D sufficiency, weight-bearing exercise and avoidance of alcohol and smoking are effective and available approaches to maintain and improve bone health in all settings. More data are needed to inform therapies and monitoring for HIV-infected youth with proven bone fragility. While very limited data suggest lack of marked increase in fracture risk for youth with perinatal HIV infection, the looming concern for these children is that they may fail to attain their expected peak bone mass in early adulthood which could increase their risk for fractures and osteoporosis later in adulthood. 相似文献
55.
56.
Adeleh Dehghani Nazhvani Reza Boostani Somayeh Afrasiabi Khadijeh Sadatnezhad 《Clinical neurology and neurosurgery》2013
Objectives
Children with Bipolar Mood Disorder (BMD) and those with Attention Deficit Hyperactivity Disorder (ADHD) share many clinical signs and symptoms; therefore, achieving an accurate diagnosis is still a challenge, especially in the first interview session. The main focus of this paper is to quantitatively classify the ADHD and BMD patients using their Visual Evoke Potential (VEP) features elicited from their Electroencephalogram (EEG) signals.Methods and materials
In this study, 36 subjects were participated including 12 healthy ones, 12 patients with ADHD and 12 ones with BMD. The age of ADHD patients was 16.92 ± 6.29 and for the BMD ones was 17.85 ± 3.68. Their scalp EEG signals in the presence of visual stimulus were recorded using 22 silver electrodes located according to the 10–20 international recording protocol. To extract their VEP, first a preprocessing step was executed to remove the power line and movement artifacts. Afterward, the wavelet denoising and synchronous averaging were applied to the preprocessed trials in order to elicit the P100 component. To obtain interpretable features from the evoked patterns, amplitude and latency were extracted and applied to the 1-Nearest Neighbor (1NN) classifier due to the locally scattered distribution of the VEP features.Results
The evaluation was performed according to leave-one(subject)-out method and the experimental results were led to 92.85% classification accuracy which is a fairly promising achievement to distinguish the BMD, ADHD, and healthy subjects from each other.Conclusion
From the physiological point of view, this result point out to the existence of significant difference in the neural activities of their visual system in the ADHD, BMD, and healthy subjects in response to a periodic optical stimulus. 相似文献57.
目的 探讨锝亚甲基二膦酸盐(99Tc-MDP)联合骨化三醇治疗原发性骨质疏松症的临床疗效.方法 将明确诊断的原发性骨质疏松症患者随机分成3组.治疗组(第1组)应用99Tc-MDP联合骨化三醇连续治疗12个月,对照组单独应用9Tc-MDP(第2组)或骨化三醇(第3组)进行治疗.观察并记录治疗前后患者的骨痛程度、骨密度值、血清骨特异性碱性磷酸酶(BALP)、骨钙素的变化情况.结果 共纳入117例患者,每组39例.3组治疗前骨痛程度、骨密度值、BALP、骨钙素均有可比性.第1组与第2组,第1组与第3组治疗后各项指标比较,第1组骨痛有效缓解率(94.9%)较第2组(74.4%)、第3组(71.8%)明显增高(P均<0.05),骨密度明显增高[(0.699±0.083) g/cm2 vs.(0.651±0.101)~cm2,P< 0.05;(0.699±0.083) g/cm2 vs.(0.647±0.092) g/cm2,P< 0.05],BALP明显降低[(14.09±1.56)ng/ml vs.(15.54±0.83)ng/ml,P<0.05;(14.09± 1.56)ng/ml vs.(15.65± 1.09)ng/ml,P<0.05],骨钙素明显降低[(6.01±1.58) ng/ml vs.(6.22±1.64)ng/ml,P<0.05;(6.01±1.58)ng/ml vs.(6.14±1.43)ng/ml,P<0.05].结论 99Tc-MDP联合骨化三醇治疗原发性骨质疏松症疗效明显,无明显不良反应. 相似文献
58.
Zhangan Zheng Helena Johansson Nicholas C. Harvey Mattias Lorentzon Liesbeth Vandenput Enwu Liu John A. Kanis Eugene V. McCloskey 《Journal of bone and mineral research》2022,37(6):1117-1124
Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to have weak but beneficial effects on bone health, including fracture risk, but many epidemiological studies are likely confounded. We explored the relationship between NSAIDs and fracture risk in a post hoc analysis of a well-documented, randomized, placebo-controlled study of the bisphosphonate, clodronate, in which treatment reduced osteoporotic fracture risk by 23%. Concurrent medication use at baseline was used to identify those prescribed oral NSAIDs. Only verified, incident fractures were included in the analysis. A total of 1082 (20.8%) women reported use of NSAIDs at baseline. They were slightly, but significantly, younger (mean 79 versus 80 years, p = 0.004), heavier (mean 66.7 versus 64.7 kg, p < 0.001) than nonusers, with slightly higher femoral neck bone mineral density (FN-BMD, 0.66 versus 0.64 g/cm2, p < 0.001). In an adjusted model, NSAID use was associated with a significant increase in osteoporotic fracture risk over the 3-year study period (hazard ratio [HR] 1.27; 95% confidence interval [CI], 1.01–1.62; p = 0.039). However, this increase in risk was not statistically significant in the placebo group (HR 1.11; 95% CI, 0.81–1.52). In women receiving clodronate, the effect of the bisphosphonate to reduce osteoporotic fracture risk was not observed in those receiving NSAIDs (HR 0.95; 95% CI, 0.65–1.41; p = 0.81) in contrast to those not using NSAIDs (HR 0.71; 95% CI, 0.58–0.89; p = 0.002). In a subset with hip BMD repeated at 3 years, BMD loss during clodronate therapy was greater in those women receiving NSAIDs than in nonusers (eg, total hip −2.75% versus −1.27%, p = 0.078; femoral neck −3.06% versus −1.12%, p = 0.028), and was not significantly different from that observed in women receiving placebo. The efficacy of the bisphosphonate, clodronate, to reduce fracture risk was largely negated in those receiving NSAIDs. Although the mechanism is unclear, this clinically significant observation requires exploration in studies of commonly used bisphosphonates. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献
59.
目的调查北京市中老年女性年龄、月经和身体成分特征,分析其与骨密度的关系以及对骨密度的影响。方法招募45~80岁女性384名,调查受试者月经状况,包括初潮年龄、绝经年龄和绝经年限;测试受试者腰椎、左股骨颈、左髋以及全身骨密度,并测试全身脂肪和肌肉含量,由此计算脂肪含量指数(fat mass index,FMI)、肌肉含量指数(lean mass index,LMI)和四肢骨骼质量指数(appendicular skeletal muscle mass index,ASMI)。采用Pearson相关和多元逐步回归模型分析各因素与骨密度的关系。结果相关性结果显示,年龄、绝经年限、初潮年龄与骨密度呈显著负相关,绝经年龄、LMI、FMI和ASMI与骨密度呈显著正相关。多元逐步回归分析结果显示,绝经年限与各部位骨密度均呈显著负相关,ASMI与各部位骨密度均呈显著正相关,FMI仅与全髋和全身骨密度具有显著相关性,初潮年龄和绝经年龄仅与腰椎和全身骨密度具有显著相关性。结论绝经年限是中老年女性骨密度的独立危险因素,而ASMI则为独立保护因素,绝经年龄、初潮年龄以及FMI对中老年女性骨密度的影响存在部位差异性。 相似文献
60.
Effects of Odanacatib on the Radius and Tibia of Postmenopausal Women: Improvements in Bone Geometry,Microarchitecture, and Estimated Bone Strength
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Angela M Cheung Sharmila Majumdar Kim Brixen Roland Chapurlat Thomas Fuerst Klaus Engelke Bernard Dardzinski Antonio Cabal Nadia Verbruggen Shabana Ather Elizabeth Rosenberg Anne E de Papp 《Journal of bone and mineral research》2014,29(8):1786-1794
The cathepsin K inhibitor odanacatib (ODN), currently in phase 3 development for postmenopausal osteoporosis, has a novel mechanism of action that reduces bone resorption while maintaining bone formation. In phase 2 studies, odanacatib increased areal bone mineral density (aBMD) at the lumbar spine and total hip progressively over 5 years. To determine the effects of ODN on cortical and trabecular bone and estimate changes in bone strength, we conducted a randomized, double‐blind, placebo‐controlled trial, using both quantitative computed tomography (QCT) and high‐resolution peripheral (HR‐p)QCT. In previously published results, odanacatib was superior to placebo with respect to increases in trabecular volumetric BMD (vBMD) and estimated compressive strength at the spine, and integral and trabecular vBMD and estimated strength at the hip. Here, we report the results of HR‐pQCT assessment. A total of 214 postmenopausal women (mean age 64.0 ± 6.8 years and baseline lumbar spine T‐score –1.81 ± 0.83) were randomized to oral ODN 50 mg or placebo, weekly for 2 years. With ODN, significant increases from baseline in total vBMD occurred at the distal radius and tibia. Treatment differences from placebo were also significant (3.84% and 2.63% for radius and tibia, respectively). At both sites, significant differences from placebo were also found in trabecular vBMD, cortical vBMD, cortical thickness, cortical area, and strength (failure load) estimated using finite element analysis of HR‐pQCT scans (treatment differences at radius and tibia = 2.64% and 2.66%). At the distal radius, odanacatib significantly improved trabecular thickness and bone volume/total volume (BV/TV) versus placebo. At a more proximal radial site, odanacatib attenuated the increase in cortical porosity found with placebo (treatment difference = –7.7%, p = 0.066). At the distal tibia, odanacatib significantly improved trabecular number, separation, and BV/TV versus placebo. Safety and tolerability were similar between treatment groups. In conclusion, odanacatib increased cortical and trabecular density, cortical thickness, aspects of trabecular microarchitecture, and estimated strength at the distal radius and distal tibia compared with placebo. © 2014 American Society for Bone and Mineral Research 相似文献