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生物力学已被证实是骨组织生长、重建及成形当中一个十分重要的因素. 骨组织的损
伤修复过程本质上是细胞的生物学过程和应力作用下的生长过程. 这虽然肯定了生物力学在
骨组织生长、重建过程中的重要地位, 但是, 人们对生物力学因素如何诱导骨生长、
重建的力学生物学机制仍不甚了解. 而骨组织工程需要更为科学完善的细胞生物学机制来研究和探
索骨组织的构建过程. 本文概述了国内外生物力学与骨组织生长重建的宏微观理论, 主要讨
论了骨组织结构及功能形成过程中的力学生物学相关问题. 相似文献
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Since the early 1990s, tissue engineering has been heralded as a strategy that may solve problems associated with bone grafting procedures. The original concept of growing bone in the laboratory, however, has proven illusive due to biological, logistic, and regulatory problems. Fat-derived stem cells and synthetic polymers open new, more practicable routes for bone tissue engineering. In this paper, we highlight the potential of poly(L-lactide-co-caprolactone) (PLCL) to serve as a radiolucent scaffold in bone tissue engineering. It appears that PLCL quickly and preferentially binds adipose stem cells (ASCs), which proliferate rapidly and eventually differentiate into the osteogenic phenotype. An in vivo spinal fusion study in a goat model provides a preclinical proof-of-concept for a one-step surgical procedure with ASCs in bone tissue engineering. 相似文献
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Kim BJ Kim SY Cho YS Kim BJ Han BG Park EK Lee SH Kim HY Kim GS Lee JY Koh JM 《Experimental & molecular medicine》2011,43(2):71-81
There is increasing evidence of a biochemical link between lipid oxidation and bone metabolism. Paraoxonase 1 (PON1) prevents the oxidation of low-density lipoprotein (LDL) and metabolizes biologically active phospholipids in oxidized LDLs. Here, we performed association analyses of genetic variation in PON1 to ascertain its contribution to osteoporotic fractures (OFs) and bone mineral density (BMD). We directly sequenced the PON1 gene in 24 Korean individuals and identified 26 sequence variants. A large population of Korean postmenopausal women (n=1,329) was then genotyped for eight selected PON1 polymorphisms. BMD at the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry. Lateral thoracolumbar (T4-L4) radiographs were obtained for vertebral fracture assessment, and the occurrence of non-vertebral fractures (i.e., wrist, hip, forearm, humerus, rib, and pelvis) was examined using self-reported data. Multivariate analyses showed that none of the polymorphisms was associated with BMD at either site. However, +5989A>G and +26080T>C polymorphisms were significantly associated with non-vertebral and vertebral fractures, respectively, after adjustment for covariates. Specifically, the minor allele of +5989A>G exerted a highly protective effect against non-vertebral fractures (OR=0.59, P=0.036), whereas the minor allele of +26080T>C was associated with increased susceptibility to vertebral fractures (OR=1.73, P=0.020). When the risk for any OFs (i.e., vertebral or non-vertebral) was considered, the statistical significance of both polymorphisms persisted (P=0.002-0.010). These results suggest that PON1 polymorphisms could be one of useful genetic markers for OF risk in postmenopausal women. 相似文献
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Molecular Control of Bioactivity in Sol-Gel Glasses 总被引:2,自引:0,他引:2
Hench Larry L. Wheeler Donna L. Greenspan David C. 《Journal of Sol-Gel Science and Technology》1998,13(1-3):245-250
Bioactive materials can be divided into: Class A bioactive glasses which exhibit rapid bonding to bone and soft connective tissue and are osteoproductive, and osteoconductive; and Class B bioactive ceramics, which bond slowly only to bone and are only osteoconductive. Bioactive sol-gel glasses composed of SiO2-CaO-P2O5 have Class A behavior in vitro and in vivo and also resorb as they enhance the proliferation of new trabecular bone. 相似文献
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Study of the circumstance influence on the elemental distribution in ancient animal bone using μ-XRF
Elemental analysis of archaeological bone plays an important role in the study of the dietary habits of ancient animals. The elemental characteristic of diagenetic skeletons depends on the surrounding circumstance. The study of environmental influence on the elemental concentration of ancient bone is significant. In this paper, the diagenetic influence on archaeological skeletons is analyzed by microbeam X-ray fluorescence (p.-XRF). The results show that the enamel is an excellent barrier to the diagenesis and the element Sr in bone isn't susceptible to contamination from the buried environment. 相似文献
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A. Kaul 《Isotopes in environmental and health studies》2013,49(2):54-59
The calculation of the dose rate and cumulative dose in the morrow-free skeleton and bone marrow of thorotrast patients presupposes the knowledge of both the translocation of thorium daughters to the skeleton, and the portion of 232Th that is localized in colloidal form in the bone marrow. Whereas in bon marrow 228Th is in equilibrium with 232Th up to only 20%, in marrow-free skeleton 228Th is present in excess to 232Th (average activity ratio 1·75), considering the measured activity ratios between 232Th and its daughters as well as the distribution of the colloid and the unclides of the thorium decay chain within the organism the dose rate and cumulative dose in bone marrow and marrow-free bone were calculated as function of the time of thorotrast burden and the amount of injected material. 相似文献