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1.
人皮质骨矿化基质中骨盐框架结构 总被引:2,自引:0,他引:2
目的:研究人皮质骨矿化基质中骨盐的框架结构及框架中骨微间隙。方法:应用透射电镜、场发射扫描电镜观察、电脑图像分析及能谱分析,分析无骨病成人长骨、扁骨200例骨盐分布特征。结果:骨盐框架结构由微柱、微梁、微小梁、弓状梁、致密点、隔板和骨微间隙构成。骨微间隙由洞、内衬和壁组成,洞平均直径为84.4±75.6nm,与骨小管相比有显著差异(P值<0.001),平均密度为11~17个/μm2,与骨小管之比超过10:1。骨盐分针形结晶和微颗粒结晶。结论:骨盐框架结构及骨微间隙是骨盐在人皮质骨矿化基质中的存在形式,可能与骨盐吸收、沉着有关。 相似文献
2.
用单光子吸收法对足月孕妇尺、桡骨骨矿物质含量(BMC)、骨面密度(BMC/BW)进行测定及作血清钙、磷的生化测定。结果显示:足月孕妇的尺、桡骨骨矿物质含量、骨面密度明显低于同年龄组的未孕妇女。主要因为妊娠胎儿的骨胳生长发育,需要孕妇向胎儿输送大量的钙离子,若母亲对钙摄入不足或吸收不良,则造成孕妇的骨矿物质含量降低,骨质疏松;而孕妇血清钙、磷降低不明显。 相似文献
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Xiaoyue Xu Zumin Shi Gang Liu Dennis Chang Sally C. Inglis John J. Hall Aletta E. Schutte Julie E. Byles Deborah Parker 《Nutrients》2021,13(3)
It is unknown whether a healthy diet or unhealthy diet combined with specific supplements may jointly contribute to incidence of obesity and cardiovascular disease (CVD). We included 69,990 participants from the 45 and Up Study who completed both baseline (2006–2009) and follow-up (2012–2015) surveys. We found that compared to participants with a long-term healthy diet and no supplement consumption, those with a long-term healthy diet combined with multivitamins and minerals (MVM) or fish oil consumption were associated with a lower incidence of CVD (p < 0.001); whilst those with an unhealthy diet and no MVM or fish oil consumption were associated with a higher risk of obesity (p < 0.05). Compared to participants with a long-term healthy diet and no calcium consumption, the combination of a long-term healthy diet and calcium consumption was linked to a lower risk of CVD (IRR = 0.87, 95% CI: 0.78; 0.96). In conclusion, a long-term healthy diet combined with MVM or fish oil was associated with a lower incidence of CVD. Participants who maintained a healthy diet and used calcium supplements were associated with a lower incidence of obesity. However, these associations were not found among those with an unhealthy diet, despite taking similar supplements. 相似文献
5.
Ahmed Anees Alani Ruslan Lesovik Valery Lesovik Roman Fediuk Sergey Klyuev Mugahed Amran Mujahid Ali Afonso R. G. de Azevedo Nikolai Ivanovich Vatin 《Materials》2022,15(17)
Due to renovation and fighting in the world, a huge accumulation of construction and demolition waste is formed. These materials are effectively used as aggregates, but there is very little information about the use of scrap concrete to create cementless binders. The purpose of the work is to be a comprehensive study of the composition and properties of concrete wastes of various fractions with the aim of their rational use as cementless binders. The scientific novelty lies in the fact that the nature of the processes of structure formation of a cementless binder based on sandy fractions of the screening of fragments of destroyed buildings and structures, as a complex polyfunctional system, has been theoretically substantiated and experimentally confirmed. Different percentages of non-hydrated clinker minerals in concrete scrap were determined. In the smallest fraction (less than 0.16 mm), more than 20% of alite and belite are present. Waste of the old cement paste is more susceptible to crushing compared to the large aggregate embedded in it, therefore, particles of the old cement paste and fine aggregate predominate in the finer fractions of the waste. Comprehensive microstructural studies have been carried out on the possibility of using concrete scrap as a completely cementless binder using scanning electron microscopy, X-ray diffraction analysis, and differential thermal analysis. It has been established that for cementless samples prepared from the smallest fractions (less than 0.315 mm), the compressive strength is 1.5–2 times higher than for samples from larger fractions. This is due to the increased content of clinker minerals in their composition. The compressive strength of the cementless binder after 28 days (7.8 MPa), as well as the early compressive strength at the age of 1 day after steaming (5.9 MPa), make it possible to effectively use these materials for enclosing building structures. 相似文献
6.
T L Bazzarre S D Murdoch S M Wu R G Hopkins 《Journal of the American College of Nutrition》2013,32(1):42-49
The purpose of this study was to examine the relationships of several cardiovascular disease risk factors [blood pressure (BP), total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-C), and the HDL-C:TC ratio], as well as the body mass index (BMI) and percent body fat with daily energy intake (EI) and daily energy expenditure (EE) of North Carolina farmers and their wives. Data were collected from 195 subjects. Daily EI and EE were estimated from 4-day food and 4-day activity records, respectively, collected on the same days. Pearson correlation coefficients for chronic disease risk factors with both EI and EE were generally low. When compared to EI, EE was more highly correlated with both lean body mass (r = 0.88) and BMI (r = 0.73), and was less time consuming and easier for the subjects to use. EE obtained from a reliable activity record may be a more practical tool for assessing the possible relationship(s) of energy metabolism to chronic disease risk factors. 相似文献
7.
C. H. S. Ruxton 《Nutrition Bulletin》2011,36(1):6-19
In 2004, The UK government advice stated that consumers should increase fish consumption to two portions a week, one of which should be oil‐rich fish. However, survey data show that this advice has not been acted upon by most members of the public. In addition, limited data on consumer attitudes highlight barriers to increased fish consumption, such as concerns about buying and cooking fish, perceptions that fish is expensive, and worries that fish meals may not be eaten by all family members. The ‘two‐a‐week’ message is underpinned by strong scientific evidence for heart health, while weaker emerging evidence associates certain nutrients found in fish with a lower risk of immune dysfunction, normal brain development in infants, insulin sensitivity and maintenance of cognitive function in later life. Clearly, further refinement of the two‐a‐week message is needed to ensure that greater numbers of people respond. Ideas include determining appropriate portion sizes for babies and children, increasing awareness of the broad range of fish and shellfish species, highlighting sustainable sources of fish, and reassuring consumers that frozen and prepared fish products count towards the two‐a‐week target. Further work is also needed to address barriers to consumption, particularly among teenagers and younger adults, who have the lowest intakes. 相似文献
8.
Sambasivam Manikandaselvi Vellingiri Vadivel Pemaiah Brindha 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2016,24(3):508
In the present, work chemical composition and nutritional value of aerial parts of Cassia occidentalis L. was studied. The aerial parts of C. occidentalis possess favorable physicochemical properties with good nutritional value, such as high energy value, crude fibers, and vitamin levels. The X-ray fluorescence spectrophotometry data revealed that the sample is rich in minerals, especially in Fe, Ca, K, and Mn. Further, minerals such as Mg, Zn, Cu, Na, P, and S are present in good amount and depicted the nutritional value of the selected material. The plant sample is rich in phytochemicals such as flavonoids, alkaloids, lignin, tannins, and phenols. The presence of phytochemical constituents was confirmed by gas chromatography–mass spectrometry profile and high-performance thin layer chromatography fingerprinting techniques. The findings stimulate the on-farm cultivation of C. occidentalis on a large scale to relieve the iron deficiency in local community, and it can be used as a dietary supplement to treat anemia. 相似文献
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目的 分析肥胖儿童与正常儿童饮食结构及营养素摄入的差异,为肥胖干预提供科学依据。方法 以2016年6月—2017年6月至西安交通大学第二附属医院儿科内分泌门诊就诊的70名7~14岁单纯性肥胖患儿及70名体重正常儿童分别作为肥胖组及对照组,测量所有儿童身高、体重、腰围、臀围、血压和体脂,并计算体重指数(BMI)及腰臀比。对所有儿童采用3日24小时回顾法调查儿童每日摄入的总热量、三大营养物质的量、微量营养素及三餐比例等情况,并采用上海惠诚有限公司的膳食营养分析软件对儿童膳食结构及营养素摄入情况分析。结果 肥胖组与对照组相比,总热量及蛋白质、脂肪及碳水化合物、脂肪及蛋白质供能比、硫胺素和维生素A、钠、锌、铁、钙的摄入量显著升高,差异均有统计学意义(P均<0.01);但碳水化合物的供能比显著降低,差异有统计学意义(P<0.01)。结论 肥胖儿童存在三大营养素及矿物质摄入比例失衡,长期营养摄入过量可导致肥胖,调整肥胖患儿的膳食结构时,需注意矿物质及维生素摄入比例。 相似文献