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51.
成都郊区学龄前儿童钙营养及骨矿状况的调查 总被引:2,自引:1,他引:1
目的:了解郊区学龄前儿童的膳食钙营养及骨矿发育状况。方法:随机选取成都郊区两所幼儿园,对161名3~6岁儿童进行膳食调查,检测血钙、尿钙,并用DEXA法、超声骨量分别测腰椎骨矿及跟骨骨量。结果:郊区学龄前儿童膳食钙营养状况仍较差。只达推荐量的32%左右;低血钙、低尿钙百分率分别为42.24%、63.34%;骨量、骨密度、骨面积与体重、身高呈正相关,学龄前儿童已表现出骨密度差异,男孩较女孩高,郊区学龄前儿童骨矿状况较城市同龄儿童为低。结论:郊区学龄前儿童由于膳食结构不合理。钙营养不足,低尿钙、血钙发生率较高,骨量发育较城市明显落后。必须加强人们对钙营养重要性的认识,调整膳食结构,多食人奶制品、豆制品等含钙丰富的食物,改普钙营养状况。促进达到最佳骨量。 相似文献
52.
Cystic Fibrosis has effects on many body systems, including the skeletal system. In this case, we describe the impact of respiratory and endocrine disease on bone healing following orthopedic trauma in a 22-year-old woman. Limitations to mobility resulting from trauma complicated her respiratory condition. Disease-related effects on bone health and healing delayed her recovery from the trauma. It is important to recognize the multisystemic nature of CF, even when managing acute orthopedic injuries. 相似文献
53.
Teriparatide vs. calcitonin in the treatment of Asian postmenopausal women with established osteoporosis 总被引:4,自引:0,他引:4
J. S. Hwang S. T. Tu T. S. Yang J. F. Chen C. J. Wang K. S. Tsai 《Osteoporosis international》2006,17(3):373-378
This study compared the clinical efficacy, safety, and tolerability of daily subcutaneous injections of teriparatide and salmon
calcitonin in the treatment of postmenopausal women with established osteoporosis in Taiwan. This 6-month, multicenter, randomized,
controlled study enrolled 63 women with established osteoporosis. They were randomized to receive either teriparatide 20 μg
or calcitonin 100 IU daily in an open-label fashion. Lumber spine, femoral neck, total hip bone mineral density (BMD), and
biochemical markers of bone turnover were measured, and adverse events and tolerability were recorded. The results at 6 months
showed that patients using teriparatide had larger mean increases in spinal BMD than those who used calcitonin (4.5% vs. 0.1%),
but the BMD changes in these two groups at the femoral neck and the total hip were not significant. There were also larger
mean increases in bone markers in the teriparatide group than in the calcitonin group (bone specific alkaline phosphatase
142% vs. 37%; osteocalcin 154% vs. 23%). We conclude that teriparatide has more positive effects on bone formation than salmon
calcitonin, as shown by the larger increments of lumbar spine BMD and bone formation markers, and caused only mild adverse
events and no significant change in liver, kidney or hematological parameters. Compared with the published global results,
teriparatide seems to be equally effective and safe to use in this Asian population. 相似文献
54.
Angular bundle kindling is accelerated in rats with a genetic predisposition to acoustic stimulus-induced seizures 总被引:5,自引:0,他引:5
Limbic kindling was examined in genetically epilepsy-prone (GEPR) and non-epileptic control rats. The early stage of kindling development was accelerated in both groups of GEPR rats compared to controls. Later stages of kindling were accelerated in GEPR-9 but not GEPR-3 rats. These results indicate that GEPR rats have an enhanced susceptibility to limbic kindling and suggest that limbic brain alterations may contribute to acceleration of the early stage kindling development in GEPR rats. 相似文献
55.
Fengxiu Ouyang Binyan Wang Lester M. Arguelles Xiping Xu Jianhua Yang Zhiping Li Liuliu Wang Xue Liu Genfu Tang Houxun Xing Craig Langman Xiaobin Wang 《Archives of osteoporosis》2007,2(1-2):29-43
Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up.
Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone
growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences.
Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based
twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at
baseline and a 6-yr follow-up.
Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”.
Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr,
but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind
peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr
follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced
bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs.
Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually
dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores
the importance that osteoporosis prevention should begin in childhood and adolescence.
Fengxiu Ouyang and Binyan Wang contributed equally to this article.
Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National
Institute of Health and by the Food Allergy Project. 相似文献
56.
同种异体骨支撑架微创治疗股骨头坏死的临床研究 总被引:1,自引:0,他引:1
目的应用改良髓芯减压术结合同种异体骨支撑架加自体骨和脱钙骨基质(decalcified bone matrix,DBM)治疗早期股骨头坏死,探索早期股骨头坏死的微创治疗方法。方法2004年1月~2005年4月,23例24个髋关节采用经大转子下通过股骨颈钻隧道至股骨头骨坏死区,将装有自体松质骨和DBM的同种异体骨支撑架经隧道拧入骨坏死区直至软骨下骨约5mm处,隧道远端用自体髂骨填塞。观察手术前后Harris评分变化、x线影像学表现及是否需进一步治疗。结果本组所有患者均获得随访,平均随访19(12—27)个月,以最后一次随访资料作为最终评价依据。Harris评分,术前优良率为43.5%(10/23)。术后优良率为91.3%(21/23)。22侧髋关节影像学表现保持稳定,无明显并发症发生。结论同种异体骨支撑架植入结合自体松质骨和DBM治疗成人股骨头坏死,增加了股骨头负重区软骨下骨的机械支撑,成骨作用强,有利于股骨头坏死的修复与重建,同时,不破坏患者股骨头本身的血液供应,创伤小,操作简单,值得临床推广使用。 相似文献
57.
目的应用重组人骨形态发生蛋白4基因腺相关病毒载体(AAV-hBMP4)转染兔骨髓基质干细胞(BMSCs),观察其对BMSCs生物学行为的影响,从而为骨组织工程寻找理想的病毒载体及种子细胞。方法全骨髓法培养兔BMSCs,按感染复数(MOI)值不同设定为四组,分别转染兔BMSCs,观察病毒量对细胞形态的影响。选取影响最小的MOI值,进行后续实验。转染兔BMSCs,MTT法描记细胞生长曲线,观察AAV对细胞增殖活性的影响。以重组增强型绿色荧光蛋白基因的腺相关病毒载体(AAV-EGFP)为参照,行流式细胞仪检测,计算转染效率。AAV-hBMP4与对照病毒AAV-EGFP分别转染细胞,观察细胞形态,行碱性磷酸酶(ALP)染色、Von Kossa染色及ALP含量测定,观察成骨活性。兔肌袋实验观察异位成骨情况。结果MOI值为5×10~4 vg/cell时,AAV对细胞形态影响最小,以此值进行后续实验。AAV转染后,细胞增殖活性良好,转染效率为55%~65%。AAV-hBMP4转染后,细胞形态呈现典型的成骨改变,ALP染色及Von Kossa染色均出现成骨的特征性改变,而AAV-EGFP组无上述改变。细胞上清ALP含量测定显示,实验组ALP含量显著增高,与对照组比较差异有统计学意义(t=218.65,P<0.01)。兔肌袋实验术后4周组织学检测可见大量钙盐沉积,矿化结节形成。结论AAV-hBMP4转染效率高,对BMSCs的增殖活性影响小,AAV-hBMP4转染的BMSCs可望成为组织工程化骨的理想种子细胞。 相似文献
58.
G. Burastero N. Sessarego G. Grappiolo C. Castellazzo S. Castello A. Pitto G. Cittadini M. Podesta G. Bovio M. Peresi E. Fulcheri F. Frassoni L. Spotorno 《Journal of orthopaedics and traumatology》2007,8(1):49-54
Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several
proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro
and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action
on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group
G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated
with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging
between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed
by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like
structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly
superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological
study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the
healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate
the best dosage. 相似文献
59.
目的 研究h-BMP-2基因转染骨髓间充质干细胞(BMSCs)在复合煅烧骨、β-TCP或直接植入裸鼠股部后的成骨能力。方法 通过影像学、组织学和形态计量学等方法,观察未经诱导、OS液诱导和h-BMP-2基因转染BMSCs在复合煅烧骨,或多孔β-TCP后植入裸鼠皮下,或直接制成细胞悬液注入,在4、8、12周诱导成骨和材料降解情况。结果 在裸鼠皮下,单纯生物陶瓷不能诱导成骨,而复合了未诱导、OS液诱导和h-BMP-2基因转染BMSCs的生物陶瓷均能成骨,成骨量为h-BMP-2基因转染组>OS液诱导组>未经诱导组(P<0.05),B-TCP可随骨长入而降解;注入裸鼠肌肉的OS液诱导的和h-BMP-2转染的BMSCs均能诱导成骨,而未经诱导MSCs则不能成骨。结论 复合人BMP基因转染BMSCs的β-TCP是一种理想的骨修复材料。 相似文献
60.
Saskia L.M.A. Beeres MD Katja Zeppenfeld MD Jeroen J. Bax MD Petra Dibbets-Schneider Marcel P.M. Stokkel MD Willem E. Fibbe MD Ernst E. van der Wall MD Douwe E. Atsma MD Martin J. Schalij MD 《Heart rhythm》2007,4(3):257-265
BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium. 相似文献