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为探讨温州地区绝经后女性骨质疏松症(Postmenopausal osteoporosis,PMOP)与雌激素受体基因(Estrogen receptor,ERa)多态性及相关因素的关联性,将203例观察对象按骨质疏松症诊断标准分为骨量正常组、骨量减少组与PMOP组,分别检测各组观察对象的腰椎L1~4正位骨密度、PvuⅡ、XbaⅠ基因型并调查其膳食行为与运动习惯等项目。结果显示:(1)年龄越大、文化程度越低、身材矮小及BMI低者、妊娠次数越多、产次越多者易罹患PMOP;经常饮用牛奶、豆浆、茶,经常食用水产品、豆类、肉类、蛋类、水果、坚果及每月运动次数较多者与高骨密度有关;在校正年龄、文化程度、BMI等干扰因素之后,饮茶、食用水果、坚果类的次数与BMD呈正相关。(2)该研究未发现PvuⅡ与XbaⅠ基因型与PMOP间有关联。提示该地区膳食行为、环境因素与PMOP关系密切,但雌激素受体α多态性与骨密度间关系尚不明确,其对骨质疏松的预测价值尚待深入研究。 相似文献
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本研究探讨基于磁共振成像(MRI)的绝经后女性腰椎退行性病变程度与骨质疏松的关系。选取经骨密度检查确诊的骨质疏松绝经后女性患者50例为骨质疏松组、非骨质疏松症绝经后妇女50例作为对照组,两组妇女均接受MRI检查。结果显示,骨质疏松组的L1/L2、L2/L3、L3/L4、L4/L5、L1~S1椎间盘Pfirrmann分级评分均高于对照组,差异均具有统计学意义(P<0.05);骨质疏松组患者的腰椎L1/L2、L2/L3、L3/L4、L4/L5、L1~S1之间的BMD与椎间盘Pfirrmann分级评分呈显著的正相关关系(P<0.05);多元线性回归模型结果显示:绝经时间、年龄、腰椎BMD值与患者椎间盘Pfirrmann分级评分呈显著的正相关关系(P<0.05)。绝经后女性采用MRI检查评估的腰椎退行性病变程度Pfirrmann分级评分与骨质疏松程度有关,同时与患者的年龄、绝经时间长度有关。 相似文献
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目的分析探讨骨质疏松症老年人微量元素含量变化。方法选取2014年7月—2015年6月到佛山市第一人民医院就诊的老年患者200例为研究对象,男性53例,女性147例,根据BMD分组为正常组、骨量低下组与骨质疏松组,对比分析男性与女性,不同BMD分组之间的微量元素含量。结果女性腰椎和股骨颈骨密度均明显低于同年龄的男性(P0.05),且绝经后女性更容易发生骨质疏松。男性微量元素Fe、Zn、Cd含量显著高于女性(P0.05);而Cu含量则显著低于女性(P0.05)。男性组中,骨质疏松组血清Fe、血清Cd含量均显著高于骨量正常组(P0.05)。女性组中,骨质疏松组血清Se、血清Pb含量显著高于正常组(P0.01)。结论老年骨质疏松症的发生与老年人机体内微量元素含量降低、营养代谢能力减弱等因素存在较大关系,故积极探究影响骨质疏松症老年人的微量元素及膳食因素具有重要意义。 相似文献
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采用远紫外圆二色光谱法系统地研究了细胞红蛋白(cytoglobin, Cygb)的浓度、环境温度、溶液的pH值和溶剂性质对细胞红蛋白二级结构的影响.结果表明: 当Cygb浓度<1 μmol/L时,它主要以α-螺旋形式存在,其α-螺旋含量>60%; 当Cygb浓度从0.3 μmol/L增大到2.0 μmol/L时,其α-螺旋含量迅速降低;当Cygb浓度>2.0 μmol/L时,其α-螺旋含量随浓度的增大变化很小(约30%).随着温度的升高,Cygb的α-螺旋含量逐渐减小,但既使温度达到368 K,它仍保持有20%的α-螺旋结构,说明该蛋白具有较高的热稳定性.在弱酸性和弱碱性溶液中,Cygb的二级结构都会有不同程度的破坏.在甲醇和乙醇中,Cygb的α-螺旋含量明显增加,这说明醇类可以诱导其α-螺旋的生成. 相似文献
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锗的环境生态研究 总被引:12,自引:0,他引:12
谢永泉 《广东微量元素科学》1998,5(2):23-25
锗是分散性元素,在动、植物中属于微量,超微量元素。在动物中,锗多存在于肝脏、肌肉,亦见于骨骼及鱼鳃中,在植物中,锗主要分布于叶子及糖类淀粉贮藏的器官中。通过动植物肿瘤的分析,说明锗不是致病元素。锗用于保健,主要在于促进糖类代谢,提高免疫力,而不是直接杀死癌细胞或其它病原体。 相似文献
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Ciro Menale Gaia Tabacco Anda Mihaela Naciu Maria Lucia Schiavone Francesca Cannata Emanuela Morenghi Cristina Sobacchi Andrea Palermo 《Molecules (Basel, Switzerland)》2022,27(12)
The dipeptidyl peptidase 3 (Dpp3) is a ubiquitous zinc-dependent aminopeptidase, participating in the activation or degradation of signaling peptides and in the Keap1–Nrf2 antioxidant pathway. The absence of Dpp3 in the Dpp3 knockout mouse model causes increased osteoclast activity, altered osteogenic function, sustained oxidative stress in the bone tissue, and bone loss. We aimed to assess the association of Dpp3 activity with bone fragility in postmenopausal osteoporosis and the impact of denosumab on enzymatic activity. We conducted a two-phase study including 69 postmenopausal women with severe osteoporosis and 36 postmenopausal women without osteometabolic conditions, as controls (cross-sectional phase). Subjects with severe osteoporosis were assessed at baseline and 14 days after the first denosumab administration (prospective phase). The results showed significant reduction in serum Dpp3 activity (expressed as nmoles of formed product/mg proteins/min) in patients vs. controls (0.791 ± 0.232 vs. 1.195 ± 0.338; p < 0.001), and significant association with bone mass at the femoral neck (r = 0.28, p = 0.02) in patients prior to treatment. We found a negative correlation between C-terminal telopeptide (CTX) or N-terminal pro-peptide of type 1 procollagen (P1NP) levels and Dpp3 activity (respectively, r = −0.29, p = 0.012; and r = −0.2572, p = 0.033). Dpp3 activity did not change after denosumab injection. Our findings support a critical role played by Dpp3 in bone homeostasis as a potential bone protective factor. Additional clinical studies in larger cohorts might explore the implementation of Dpp3 assessment as a biomarker of bone health status. 相似文献
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用ICP研究鹿科动物骨质疏松症的微量元素特征 总被引:1,自引:0,他引:1
鹿科动物的骨质疏松症是近几年出现的一种疾病,它影响鹿的生长发育和繁殖,病重者死亡。我们采集梅花鹿和白唇鹿的毛,血样,用低温灰化方法和温法消解处理样品,用ICP分析了毛,血清中微量元素的含量。病梅花鹿毛样中Mg,Al,Ca,Ti,Fe,Cu,Zn的含量比正常组高,Ti,Cu,Zn的偏差率大于15%,而Si,Mn,P,P,Ag,Ba,La,Ce,Pb比正常组低,V,Ag,Ba,La,Ce,Pb存在... 相似文献
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为研究大豆异黄酮(SI)对骨质疏松模型大鼠骨量及微观结构的影响,将46只雌性SD大鼠双侧摘除卵巢,术后一周按血清总胆固醇水平随机分为5组,分别给予雌激素,低、中、高剂量SI干预并设正常对照组,实验周期为12周,灌胃给药,每周称质量一次,分别在去卵巢、给药4、8周处死时抽取尾静脉血,实验结束后分别测定血清碱性磷酸酶(AKP)活性及骨密度等指标。结果表明,高剂量SI干预对维持大鼠骨密度的作用与雌激素相似,去卵巢后干预SI可提高碱性磷酸酶(AKP)活性并能缓解因去卵巢造成的骨丢失,全视野下骨形态学以雌激素组、高剂量SI干预组与正常组结构最为接近。提示大豆异黄酮对骨质疏松模型大鼠的骨量及微观结构存在一定影响,中、高剂量干预可使骨质疏松模型大鼠血清AKP酶活性增加、逆转因去势造成的骨密度下降,考虑到植物雌激素与哺乳动物的雌激素受体(ER)结合能力低下,采用SI在临床开展干预的剂量与远期效果尚待进一步论证。 相似文献
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为研究大豆异黄酮(SI)对骨质疏松模型大鼠骨量及微观结构的影响,将46只雌性SD大鼠双侧摘除卵巢,术后一周按血清总胆固醇水平随机分为5组,分别给予雌激素,低、中、高剂量SI干预并设正常对照组,实验周期为12周,灌胃给药,每周称质量一次,分别在去卵巢、给药4、8周处死时抽取尾静脉血,实验结束后分别测定血清碱性磷酸酶(AKP)活性及骨密度等指标.结果表明,高剂量SI干预对维持大鼠骨密度的作用与雌激素相似,去卵巢后干预SI可提高碱性磷酸酶(AKP)活性并能缓解因去卵巢造成的骨丢失,全视野下骨形态学以雌激素组、高剂量SI干预组与正常组结构最为接近.提示大豆异黄酮对骨质疏松模型大鼠的骨量及微观结构存在一定影响,中、高剂量干预可使骨质疏松模型大鼠血清AKP酶活性增加、逆转因去势造成的骨密度下降,考虑到植物雌激素与哺乳动物的雌激素受体(ER)结合能力低下,采用SI在临床开展干预的剂量与远期效果尚待进一步论证. 相似文献
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影响MFC产电能力及污水净化的非生物因素研究 总被引:1,自引:0,他引:1
以厌氧污泥接种模拟生活污水, 构建双室无介体型微生物燃料电池(MFC). 以输出功率密度、库仑效率和CODCr(化学需氧量)去除率为评价指标, 采用正交设计考察4种非生物因素(即阴、阳极材料、底物和电子受体)对MFC产电及污水净化的影响. 在此基础上进一步探讨阴极离子浓度对电能输出的影响. 结果表明: 对MFC产能及污水净化的影响因素顺序为: 电子受体>阳极>阴极>底物, 最优组合为碳毡-乳酸钠-不锈钢板-铁氰化钾+溶解氧|向阴极液中投加NaCl可使产电能力显著增强, 最佳投加量为150 mmol•L-1. 同时, 阴极室定期添加铁氰化钾可维持电流稳定. 试验中, 葡萄糖型、乳酸钠型以及混合型底物模拟污水的CODCr均得到有效去除, 平均去除率达85.2%, 显示了研究的MFC具有很强的产电和污水净化能力. 相似文献
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采用耗散颗粒动力学(DPD)模拟方法在介观层次上模拟了表面活性剂十六烷基三甲基溴化铵(CTAB)在油/水界面的自组装行为,考察了表面活性剂浓度、油水比例以及剪切力等环境因素对表面活性剂界面张力、尾-尾间距离及油水界面厚度的影响。结果发现,油水比例增大可显著降低CTAB存在的油水界面张力,提高CTAB的界面活性;有剪切存在时,表面活性剂在界面的聚集行为明显改变,分子在界面处的排列变得混乱,有序性降低,导致尾-尾间距离减小、界面厚度增加,界面效率显著降低。模拟表明,介观模拟方法可以作为实验的一种补充,为实验提供必要的微观分子结构信息。 相似文献
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Chunping Yang Yue Zhou Chuanlei Wu Xiao Yan Pengcheng Cheng Liya Luo Xiaoyan Qiu Min Zhang Guangwei Qin Yangyang Zhang Huabao Chen 《Molecules (Basel, Switzerland)》2022,27(21)
Niclosamide (NI) is the main molluscicide used to control Pomacea canaliculata (Lamarck) (Architaenioglossa: Ampullariidae). However, NI failed to inhibit snail climbing during the treatment process. In this study, we examined the effect of NI combined with pedunsaponin A at an ineffective concentration. The molluscicidal effect of Pedunsaponin A on NI was evidently synergistic after 48 h, and the synergism ratio (SR) was 1.82 after treatment for 72 h at 0.8 mg·L−1. Examination of the climbing adhesion effect showed that a high concentration of Pedunsaponin A (0.4 mg·L−1 and 0.8 mg·L−1) combined with NI significantly inhibited the climbing of P. canaliculata. We further studied the synergism mechanism; the results of histopathological observation showed that the siphon appeared cavities, the muscle fibers of the ventricular were severely dissolved, and kidney tubule arrangement was distorted after NI adding Pedunsaponin A. In addition, the hemocyte survival rate and the content of hemocyanin decreased significantly. According to the results of our study, the synergism mechanism may hinder oxygen transport of P. canaliculata, influencing the supply of energy; the ability of immune defense and excretion and metabolic detoxification decreased, prolonging the action time of NI in the body. 相似文献
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环境铅暴露对儿童智能与行为的影响 总被引:1,自引:0,他引:1
环境铅暴露对儿童的危害已成为世界范围内一种严重的公共卫生问题。既往的研究表明环境铅暴露对儿童的智力发育将产生不良影响 ,尤其是对于婴儿 ,铅暴露是影响其精神发育的决定因素之一 ;长期的铅暴露具有累加作用 ,其毒害作用也是累加的 ;铅暴露又是导致儿童行为异常的因素之一 ;大量研究显示儿童多动症与儿童铅暴露水平有关。此外 ,铅暴露还可能影响部分儿童运动功能的发育。 相似文献
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Valeria DAnnibale Donatella Fracassi Paolo Marracino Guglielmo DInzeo Marco DAbramo 《Molecules (Basel, Switzerland)》2022,27(19)
Here we present a theoretical-computational study dealing with the evaluation of the pKa of the Cysteine residues in Thioredoxin (TRX) and in its complex with the Thioredoxin-interacting protein (TXNIP). The free energy differences between the anionic and neutral form of the Cysteine 32 and 35 have been evaluated by means of the Perturbed Matrix Method with classical perturbations due to both the environment and an exogenous electric field as provided by Molecular Dynamics (MD) simulations. The evaluation of the free energies allowed us to show that the effect of the perturbing terms is to lower the pKa of Cysteine 32 and Cysteine 35 with respect to the free amino-acid. On the other hand, in the complex TRX-TXNIP, our data show an enhanced stabilization of the neutral reduced form of Cys 35. These results suggest that external electric stimuli higher than 0.02 V/nm can modulate the Cysteine pKa, which can be connected to the tight regulation of the TRX acting as an antioxidant agent. 相似文献
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Wenbo Jin Jiaqiang Jing Hongfei Wu Lei Yang Ye Li 《Journal of Dispersion Science and Technology》2014,35(10):1434-1441
The Ar-Sai waxy crude oils were taken as the research objects, and the viscosity reduction rates and the condensation point reduction rates were regarded as the evaluation indexes, the impacts of components content of the crude oils and carbon number distribution of waxes on the modification effect of EVA-type pour point depressant (PPD) were analyzed by using gray correlation analysis method. The oil wax was acquired by applying the extraction and separation techniques initially, then the structures and the lattice parameters of wax crystals before and after adding the PPD were studied by polarized light microscopy observation and x-ray diffraction techniques, the mechanism of pour point depression was discussed at last. The results indicate that wax content and the low carbon number wax have significant influences on the modification effect of PPD, while the impact of high carbon number wax is relatively small. Co-crystallization is the main mechanism of pour point depression, nevertheless, the impacts of the asphaltenes, resins, solid particles, and light components of the crude oils on the modification effect of the PPD cannot be ignored. 相似文献