Osteoporosis, characterized by loss of bone mass and microarchitectural deterioration of bone tissue, results in enhanced bone fragility and increases risk of fractureIll. In China, the incidence of primary osteoporos...Osteoporosis, characterized by loss of bone mass and microarchitectural deterioration of bone tissue, results in enhanced bone fragility and increases risk of fractureIll. In China, the incidence of primary osteoporosis is as high as 50%-70% in 60-69 years old females and approximately 30% in 60-69 years old males[21, which is closely related with the low intake of calcium. According to the nationwide nutrition and health survey in 2002 in China, the average daily calcium intake of Chinese residents is 391 mg, accounting for 41% of the recommended calcium intake.展开更多
Natural diatomite （DT） is the ancient deposit of diatom skeleton with many regular pores of 50-200 nm and also an abundant source of biogenic silica. Although silica is considered biologically safe and there is an i...Natural diatomite （DT） is the ancient deposit of diatom skeleton with many regular pores of 50-200 nm and also an abundant source of biogenic silica. Although silica is considered biologically safe and there is an increasing interest of using natural diatomite for biomedical applications, the toxicity information about natural diatomite is still missing. Here, cytotoxicity of natural diatomite on osteoblasts and fibroblasts were compared to hydroxyapatite and the relationships between cytotoxicity and diatomite sizes, dose, geometry or impurity were systematically investigated. Cell adhesion and interaction with diatomite particles were also fluorescently observed, The results clearly suggested a size-, dose- and shape-dependent cytotoxicity of natural diatomite. Disk-shaped diatomite particles with average size of 30μm in diameter revealed the least toxicity, while the diatomite particles with irregular shapes and sizes less than 10 μm were remarkably toxic. Diatomite particles with proper sizes were then selected to investigate the reinforcing effect on injectable calcium phosphate bone cement. Results showed that diatomite significantly improved the compressive strength of bone cement but did not alter the injectability of the cement, This work provided important biocompatibility information of natural diatomite and demonstrated the feasibility of using selected diatomite as bone implant material.展开更多
The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in c...The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.展开更多
The early RBE of the bone marrow in mice after studied irradiation with fast neutrons(35 MeVp→Be) was studied.60Co-γ ray was used for referent beams.Using the dos.making 50% loss of the nucleated cells of bone marro...The early RBE of the bone marrow in mice after studied irradiation with fast neutrons(35 MeVp→Be) was studied.60Co-γ ray was used for referent beams.Using the dos.making 50% loss of the nucleated cells of bone marrow in mice relative to control group mice to calculated the RBE value which was 2.13±0.18.Meanwhile,the relationship of the RBE values and the dose of neutrons was noted.On log-log plot the RBE values decrease with increasing dose of fast neutrons and it is consistent with a slope of -0.39± 0.10.The α/β ratios were estimated from linear-quadratic model of cell survival,they are 14.4±1.30 Gy for fast neutrons and 0.83±0.10 Gy for γ-ray,respectively.展开更多
Objectives: Bone defects following tumor resection and osteolysis due to dental and bone lesions and periodentium tissue disorders are serious challenges. One of these materials used is chitosan, a derivative of crust...Objectives: Bone defects following tumor resection and osteolysis due to dental and bone lesions and periodentium tissue disorders are serious challenges. One of these materials used is chitosan, a derivative of crustaceans’ exoskeleton. The aim of this study was to assess effects of chitosan on socket repair after dental extraction. Methods: Twenty four dental sockets of 15-24 years old patients were visited by a maxillofacial surgeon for extracting premolar teeth for orthodontic purposes. The sockets in one side were filled-in by chitosan. In the other side, the sockets were left unfilled. After 10 weeks, periapical radiographs were obtained from the repair sites, were digitalized and then evaluated for densitometry using Adobe Photoshop Software. Each socket was divided into coronal, middle and apical. Dental density of each socket in case and control groups was recorded. The density of regenerated bone was compared against the maximum bone density of each individual. Wilcoxon signed range test and paired t-test were used for data analysis. Results: Bone density in middle and apical sections in case group was significantly more than control group. In apical section in case group regenerated bone reached up to 98.2% of normal bone density. In each patient, the bone density in epical and middle sections was increase 29.3% and 10.8% of normal bone density. Conclusions: Chitosan significantly increased bone density in epical and middle sections. Chitosan can be used for bone repair in cases of bone loss. Various densitometry studies for evaluating chitosan effects in different bone defects are suggested.展开更多
We assessed genetic and environmental effectson bone development of the hand and wrist, andon key anthropometric measures in Chinese youngtwins. In total, 139 monozygotic and 95 dizygotictwin pairs aged from 5 to 18 y...We assessed genetic and environmental effectson bone development of the hand and wrist, andon key anthropometric measures in Chinese youngtwins. In total, 139 monozygotic and 95 dizygotictwin pairs aged from 5 to 18 years were recruited.The twin correlations of total hand and wrist scoresfor monozygotic （MZ） and dizygotic （DZ） twins were0.71 and 0.36, respectively. Bivariate modelanalysis showed moderate genetic correlations onlyfor total skeletal maturity vs. weight and totalskeletal maturity vs. waist circumference （r, 0.51and 0.46, respectively）. Our findings demonstratedthat genetic factors played important roles in bonedevelopment of the hand and wrist in Chineseyoung twins, and that these genetic effects mightbe distinct from those influencing anthropometricmeasures.展开更多
The bioactive α-Ca3（ PO4 ）2 bone cement was studied by XRD , SEM and isothermal calorimetric measurements. The results showed that a mixed pattern of TCP and hydroxylapatite were obtained after hydration and harden...The bioactive α-Ca3（ PO4 ）2 bone cement was studied by XRD , SEM and isothermal calorimetric measurements. The results showed that a mixed pattern of TCP and hydroxylapatite were obtained after hydration and hardening. The mechanism of hydration and hardening of the α-Ca3 （ PO4）2 was dissolution-precipitation, （ NH4 ） 112 PO4 was the best set accelerator to the α-Ca3 （ PO4）2 cement, and the HAP powers and the （ NH4）H2 PO4 concentration had a great effect on the hydration rate of a-Ca3（ PO4）2.展开更多
Aim: The effects of granulocyte colony- stimu-lating factor (G-CSF) and stem cell factor (SCF) on the proliferation and osteogenic differentia-tion capacity of bone marrow mesenchymal stem cells (MSCs) were studied in...Aim: The effects of granulocyte colony- stimu-lating factor (G-CSF) and stem cell factor (SCF) on the proliferation and osteogenic differentia-tion capacity of bone marrow mesenchymal stem cells (MSCs) were studied in the experi-ment. Methods: Bone marrow MSCs were col-lected from rabbits successfully, and treated with various concentrations of G-CSF, SCF or a combination of the two. Flow cytometric ana-lyse, MTT test, CFU-F assay, and alkaline phosphatase (ALP) activity measurement were employed. Results: The results of flow cytome-try showed that immunophenotype of the cells were CD29+/CD45-, CD105+/ CD34–, CD90+/ HLADR–. MSCs were shown to constitutively express low levels of c-kit which could be en-hanced by SCF. G-CSF and SCF had an obvious facilitative effect on the proliferation of MSCs in a dose-dependent fashion. In addition, G-CSF and SCF would be effective in reversibly pre-venting their differentiation, as showed by the decrease of ALP activity, leading to self-renewal rather than differentiative cell divisions. The effects of G-CSF were superior to SCF. And cells in the group treated with combination of G-CSF and SCF showed more powerful effects than the groups treated with G-CS, SCF, or none of the two. Conclusion: On the whole, these studies demonstrated that MSCs responsed to G-CSF, SCF, and to G-CSF plus SCF in a manner that suppressed differentiation, and promotes proliferation and self-renewal, and support the view that these factors could act synergistically.展开更多
Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole b...Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole bone marrow展开更多
Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.M...Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.Methods Two hundred and展开更多
背景:将中药有效成分整合于水凝胶体系,作为生长因子的替代品或与生长因子相协同,有望显著增强生物材料在骨缺损修复中的治疗效能。目的:系统总结中药有效成分在改善水凝胶材料生物相容性、机械性能等方面的优势以及中药有效成分与水凝...背景:将中药有效成分整合于水凝胶体系,作为生长因子的替代品或与生长因子相协同,有望显著增强生物材料在骨缺损修复中的治疗效能。目的:系统总结中药有效成分在改善水凝胶材料生物相容性、机械性能等方面的优势以及中药有效成分与水凝胶协同运用促进骨修复方面的最新研究进展。方法:以“中药,中药单体,水凝胶,载体,骨组织工程,生物材料,骨,骨修复,骨缺损”为中文检索词,以“Chinese medicine,Chinese medicine monomer,Hydrogel,Carrier,Bone tissue engineering,Bio-material,Bone,Bone repair,Bone defect”为英文检索词,检索2005-2025年期间中国知网、万方、PubMed、Web of Science数据库内的相关文献,依据纳入及排除标准,最终纳入66篇文献进行归纳总结。结果与结论:中药有效成分可以改善水凝胶的生物相容性、机械性能及降解性能,二者联合应用突破了单一材料在力学、生物活性等方面的瓶颈。中药有效成分与水凝胶结合后,可通过调节骨代谢、促进软骨形成、抑制炎症及氧化应激、血管化与血管生成4个维度显著提升骨修复能力。然而,目前关于中药有效成分与水凝胶结合在骨组织工程中的研究仍有不足,距离实际的临床应用仍有挑战。展开更多
We consider the problem of assessing bone fracture risk for a subject hit by a blunt impact projectile. We aim at constructing a framework for integrating test data and Advanced Total Body Model (ATBM) simulations int...We consider the problem of assessing bone fracture risk for a subject hit by a blunt impact projectile. We aim at constructing a framework for integrating test data and Advanced Total Body Model (ATBM) simulations into the risk assessment. The ATBM is a finite element model managed by the Joint Non-Lethal Weapons Directorate for the purpose of assessing the risk of injury caused by blunt impacts from non-lethal weapons. In ATBM simulations, the quantity that determines arm bone fracture is the calculated maximum strain in the bone. The main obstacle to accurate prediction is that the calculated strain is incompatible with the measured strain. The fracture strain measured in bending tests of real bones is affected by random inhomogeneity in bones and uncertainty in measurement gauge attachment location/orientation. In contrast, the strain calculated in ATBM simulations is based on the assumption that all bones are perfectly elastic with homogeneous material properties and no measurement uncertainty. To connect test data and ATBM simulations in a proper and meaningful setting, we introduce the concept of elasticity-homogenized strain. We interpret test data in terms of the homogenized strain, and build an empirical dose-injury model with the homogenized strain as the input dose for predicting injury. The maximum strain calculated by ATBM has randomness due to uncertainty in specifications of ATBM setup parameters. The dose propagation uncertainty formulation accommodates this uncertainty efficiently by simply updating the shape parameters in the dose-injury model, avoiding the high computational cost of sampling this uncertainty via multiple ATBM runs.展开更多
充足的骨组织是保证种植体长期稳定性的先决条件。Urban教授提出了基于引导骨再生(guided bone regeneration,GBR)原理的“香肠技术”。研究显示,该技术在牙槽骨水平向增量方面达(5.3±2.3)mm,垂直向增量为(4.2±1.9)mm,显著优...充足的骨组织是保证种植体长期稳定性的先决条件。Urban教授提出了基于引导骨再生(guided bone regeneration,GBR)原理的“香肠技术”。研究显示,该技术在牙槽骨水平向增量方面达(5.3±2.3)mm,垂直向增量为(4.2±1.9)mm,显著优于传统GBR方法。香肠技术利用生物膜的弹性与韧性,结合膜钉固定,将自体骨与骨移植材料稳定在植骨区域,有效防止移位并增强空间稳定性。骨替代材料和自体骨的使用兼顾了自体骨的成骨活性和骨替代材料的低吸收速率;在受区的皮质骨使用球钻进行滋养孔的制备,为间充质干细胞和骨祖细胞向骨再生区域迁移提供了通路,同时也可以加速创口愈合早期新生血管生成;充分减张缝合,以确保在缝合时不对愈合区域施加过大的压力。这有效提高了香肠技术的可预测性。尽管该技术疗效显著,但潜在的软硬组织并发症可能影响患者恢复及手术结果。因此,深入探讨其并发症及诱因,对于提升香肠技术的临床安全性和有效性具有重要意义。本文总结了香肠技术的应用原理、临床效果、屏障膜的应用、骨移植材料的选择及并发症防治,旨在为其在口腔种植领域的广泛应用提供参考。展开更多
The radioactivity level of the ambient environment of Anren Bone-coal Power Station (BCPS) was investigated systematically. The γ radiation dose rate level in the environment, the content of 238U and 226Ra in the amb...The radioactivity level of the ambient environment of Anren Bone-coal Power Station (BCPS) was investigated systematically. The γ radiation dose rate level in the environment, the content of 238U and 226Ra in the ambient soil and the farmland in the direction of downwind, the concentrations of 238U. 232Th. 226Ra 40K and 222Rn as well as α potential energy in air, and the concentrations of natural U and Th in effluent are all higher than the corresponding values of the reference site. The additional annual effective dose equivalent to the residents living in the houses made of bone-coal cinder brick is 2.7 mSv.展开更多
文摘Osteoporosis, characterized by loss of bone mass and microarchitectural deterioration of bone tissue, results in enhanced bone fragility and increases risk of fractureIll. In China, the incidence of primary osteoporosis is as high as 50%-70% in 60-69 years old females and approximately 30% in 60-69 years old males[21, which is closely related with the low intake of calcium. According to the nationwide nutrition and health survey in 2002 in China, the average daily calcium intake of Chinese residents is 391 mg, accounting for 41% of the recommended calcium intake.
基金financially supported by the National Natural Science Foundation of China(Nos.81622032,51672184,51525101and 51472279)the Priority Academic Program Development of Jiangsu High Education Institutions(PAPD)+2 种基金the Jiangsu Innovation and Entrepreneurship Program,the National Basic Research Program of China(973 Program,No.2014CB748600)the Jiangsu Provincial Special Program of Medical Science(No.BL2012004)the Jiangsu Six Peak of Talents Program(No.2013-WSW-056)
文摘Natural diatomite （DT） is the ancient deposit of diatom skeleton with many regular pores of 50-200 nm and also an abundant source of biogenic silica. Although silica is considered biologically safe and there is an increasing interest of using natural diatomite for biomedical applications, the toxicity information about natural diatomite is still missing. Here, cytotoxicity of natural diatomite on osteoblasts and fibroblasts were compared to hydroxyapatite and the relationships between cytotoxicity and diatomite sizes, dose, geometry or impurity were systematically investigated. Cell adhesion and interaction with diatomite particles were also fluorescently observed, The results clearly suggested a size-, dose- and shape-dependent cytotoxicity of natural diatomite. Disk-shaped diatomite particles with average size of 30μm in diameter revealed the least toxicity, while the diatomite particles with irregular shapes and sizes less than 10 μm were remarkably toxic. Diatomite particles with proper sizes were then selected to investigate the reinforcing effect on injectable calcium phosphate bone cement. Results showed that diatomite significantly improved the compressive strength of bone cement but did not alter the injectability of the cement, This work provided important biocompatibility information of natural diatomite and demonstrated the feasibility of using selected diatomite as bone implant material.
基金supported by the National Natural Science Funds of China(Grant No.81703664)Science and Technology Funds of Lanzhou,China(Grant No.201603111)
文摘The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.
文摘The early RBE of the bone marrow in mice after studied irradiation with fast neutrons(35 MeVp→Be) was studied.60Co-γ ray was used for referent beams.Using the dos.making 50% loss of the nucleated cells of bone marrow in mice relative to control group mice to calculated the RBE value which was 2.13±0.18.Meanwhile,the relationship of the RBE values and the dose of neutrons was noted.On log-log plot the RBE values decrease with increasing dose of fast neutrons and it is consistent with a slope of -0.39± 0.10.The α/β ratios were estimated from linear-quadratic model of cell survival,they are 14.4±1.30 Gy for fast neutrons and 0.83±0.10 Gy for γ-ray,respectively.
文摘Objectives: Bone defects following tumor resection and osteolysis due to dental and bone lesions and periodentium tissue disorders are serious challenges. One of these materials used is chitosan, a derivative of crustaceans’ exoskeleton. The aim of this study was to assess effects of chitosan on socket repair after dental extraction. Methods: Twenty four dental sockets of 15-24 years old patients were visited by a maxillofacial surgeon for extracting premolar teeth for orthodontic purposes. The sockets in one side were filled-in by chitosan. In the other side, the sockets were left unfilled. After 10 weeks, periapical radiographs were obtained from the repair sites, were digitalized and then evaluated for densitometry using Adobe Photoshop Software. Each socket was divided into coronal, middle and apical. Dental density of each socket in case and control groups was recorded. The density of regenerated bone was compared against the maximum bone density of each individual. Wilcoxon signed range test and paired t-test were used for data analysis. Results: Bone density in middle and apical sections in case group was significantly more than control group. In apical section in case group regenerated bone reached up to 98.2% of normal bone density. In each patient, the bone density in epical and middle sections was increase 29.3% and 10.8% of normal bone density. Conclusions: Chitosan significantly increased bone density in epical and middle sections. Chitosan can be used for bone repair in cases of bone loss. Various densitometry studies for evaluating chitosan effects in different bone defects are suggested.
文摘We assessed genetic and environmental effectson bone development of the hand and wrist, andon key anthropometric measures in Chinese youngtwins. In total, 139 monozygotic and 95 dizygotictwin pairs aged from 5 to 18 years were recruited.The twin correlations of total hand and wrist scoresfor monozygotic （MZ） and dizygotic （DZ） twins were0.71 and 0.36, respectively. Bivariate modelanalysis showed moderate genetic correlations onlyfor total skeletal maturity vs. weight and totalskeletal maturity vs. waist circumference （r, 0.51and 0.46, respectively）. Our findings demonstratedthat genetic factors played important roles in bonedevelopment of the hand and wrist in Chineseyoung twins, and that these genetic effects mightbe distinct from those influencing anthropometricmeasures.
文摘The bioactive α-Ca3（ PO4 ）2 bone cement was studied by XRD , SEM and isothermal calorimetric measurements. The results showed that a mixed pattern of TCP and hydroxylapatite were obtained after hydration and hardening. The mechanism of hydration and hardening of the α-Ca3 （ PO4）2 was dissolution-precipitation, （ NH4 ） 112 PO4 was the best set accelerator to the α-Ca3 （ PO4）2 cement, and the HAP powers and the （ NH4）H2 PO4 concentration had a great effect on the hydration rate of a-Ca3（ PO4）2.
文摘Aim: The effects of granulocyte colony- stimu-lating factor (G-CSF) and stem cell factor (SCF) on the proliferation and osteogenic differentia-tion capacity of bone marrow mesenchymal stem cells (MSCs) were studied in the experi-ment. Methods: Bone marrow MSCs were col-lected from rabbits successfully, and treated with various concentrations of G-CSF, SCF or a combination of the two. Flow cytometric ana-lyse, MTT test, CFU-F assay, and alkaline phosphatase (ALP) activity measurement were employed. Results: The results of flow cytome-try showed that immunophenotype of the cells were CD29+/CD45-, CD105+/ CD34–, CD90+/ HLADR–. MSCs were shown to constitutively express low levels of c-kit which could be en-hanced by SCF. G-CSF and SCF had an obvious facilitative effect on the proliferation of MSCs in a dose-dependent fashion. In addition, G-CSF and SCF would be effective in reversibly pre-venting their differentiation, as showed by the decrease of ALP activity, leading to self-renewal rather than differentiative cell divisions. The effects of G-CSF were superior to SCF. And cells in the group treated with combination of G-CSF and SCF showed more powerful effects than the groups treated with G-CS, SCF, or none of the two. Conclusion: On the whole, these studies demonstrated that MSCs responsed to G-CSF, SCF, and to G-CSF plus SCF in a manner that suppressed differentiation, and promotes proliferation and self-renewal, and support the view that these factors could act synergistically.
文摘Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole bone marrow
文摘Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.Methods Two hundred and
文摘背景:将中药有效成分整合于水凝胶体系,作为生长因子的替代品或与生长因子相协同,有望显著增强生物材料在骨缺损修复中的治疗效能。目的:系统总结中药有效成分在改善水凝胶材料生物相容性、机械性能等方面的优势以及中药有效成分与水凝胶协同运用促进骨修复方面的最新研究进展。方法:以“中药,中药单体,水凝胶,载体,骨组织工程,生物材料,骨,骨修复,骨缺损”为中文检索词,以“Chinese medicine,Chinese medicine monomer,Hydrogel,Carrier,Bone tissue engineering,Bio-material,Bone,Bone repair,Bone defect”为英文检索词,检索2005-2025年期间中国知网、万方、PubMed、Web of Science数据库内的相关文献,依据纳入及排除标准,最终纳入66篇文献进行归纳总结。结果与结论:中药有效成分可以改善水凝胶的生物相容性、机械性能及降解性能,二者联合应用突破了单一材料在力学、生物活性等方面的瓶颈。中药有效成分与水凝胶结合后,可通过调节骨代谢、促进软骨形成、抑制炎症及氧化应激、血管化与血管生成4个维度显著提升骨修复能力。然而,目前关于中药有效成分与水凝胶结合在骨组织工程中的研究仍有不足,距离实际的临床应用仍有挑战。
文摘We consider the problem of assessing bone fracture risk for a subject hit by a blunt impact projectile. We aim at constructing a framework for integrating test data and Advanced Total Body Model (ATBM) simulations into the risk assessment. The ATBM is a finite element model managed by the Joint Non-Lethal Weapons Directorate for the purpose of assessing the risk of injury caused by blunt impacts from non-lethal weapons. In ATBM simulations, the quantity that determines arm bone fracture is the calculated maximum strain in the bone. The main obstacle to accurate prediction is that the calculated strain is incompatible with the measured strain. The fracture strain measured in bending tests of real bones is affected by random inhomogeneity in bones and uncertainty in measurement gauge attachment location/orientation. In contrast, the strain calculated in ATBM simulations is based on the assumption that all bones are perfectly elastic with homogeneous material properties and no measurement uncertainty. To connect test data and ATBM simulations in a proper and meaningful setting, we introduce the concept of elasticity-homogenized strain. We interpret test data in terms of the homogenized strain, and build an empirical dose-injury model with the homogenized strain as the input dose for predicting injury. The maximum strain calculated by ATBM has randomness due to uncertainty in specifications of ATBM setup parameters. The dose propagation uncertainty formulation accommodates this uncertainty efficiently by simply updating the shape parameters in the dose-injury model, avoiding the high computational cost of sampling this uncertainty via multiple ATBM runs.
文摘充足的骨组织是保证种植体长期稳定性的先决条件。Urban教授提出了基于引导骨再生(guided bone regeneration,GBR)原理的“香肠技术”。研究显示,该技术在牙槽骨水平向增量方面达(5.3±2.3)mm,垂直向增量为(4.2±1.9)mm,显著优于传统GBR方法。香肠技术利用生物膜的弹性与韧性,结合膜钉固定,将自体骨与骨移植材料稳定在植骨区域,有效防止移位并增强空间稳定性。骨替代材料和自体骨的使用兼顾了自体骨的成骨活性和骨替代材料的低吸收速率;在受区的皮质骨使用球钻进行滋养孔的制备,为间充质干细胞和骨祖细胞向骨再生区域迁移提供了通路,同时也可以加速创口愈合早期新生血管生成;充分减张缝合,以确保在缝合时不对愈合区域施加过大的压力。这有效提高了香肠技术的可预测性。尽管该技术疗效显著,但潜在的软硬组织并发症可能影响患者恢复及手术结果。因此,深入探讨其并发症及诱因,对于提升香肠技术的临床安全性和有效性具有重要意义。本文总结了香肠技术的应用原理、临床效果、屏障膜的应用、骨移植材料的选择及并发症防治,旨在为其在口腔种植领域的广泛应用提供参考。
文摘The radioactivity level of the ambient environment of Anren Bone-coal Power Station (BCPS) was investigated systematically. The γ radiation dose rate level in the environment, the content of 238U and 226Ra in the ambient soil and the farmland in the direction of downwind, the concentrations of 238U. 232Th. 226Ra 40K and 222Rn as well as α potential energy in air, and the concentrations of natural U and Th in effluent are all higher than the corresponding values of the reference site. The additional annual effective dose equivalent to the residents living in the houses made of bone-coal cinder brick is 2.7 mSv.
