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Objective To explore the correlation between volume rendering(VR) statistics of medial clavicular epiphysis and living age,and establish the mathematical models for living age evaluation using the CT image of medial clavicular epiphysis based on the growth rules of osteoepiphysis of medial clavicle.Methods The CT images of the medial clavicles from 795 teenagers aged 15-25,387 males and 408 females,were collected in East and South China.VR 3D images were reconstructed from 0.60 mm-thick slice CT images.The epiphyseal diameter,sternal end diameter,and their respective diameter ratio(the left: x 1;the right: x 3);epiphyseal area,sternal end area,and their respective area ratio(the left: x 2;the right: x 4),were measured and calculated.All these observations were analyzed using SPSS 19.0 statistical software.The statistical differences in gender and age were analyzed by Mann-Whitney U test.The mathematical models were established using least square.Sixty trained subjects,30 males and 30 females,were tested to verify the accuracy of the established mathematical models.Results In the group of same age,x 1 showed significant difference in gender;the same results were observed in x 2,x 3,and x 4,which suggested that the growth rules of osteoepiphysis of medial clavicle were highly correlated with living age.The accuracy of these mathematical models were all above 67.6%(±1.0 year) and 78.5%(±1.5 year).Conclusion The mathematical models with reasonable accuracy could be manageable in practice to confirm the conclusion of the atlas method.The current study can contribute to the single skeletal age evaluation. 相似文献
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印度河流域文明是世界最古老的文明之一,发展水平相当高,但却很快地消失了,而且几乎没对继之而起的另一个文明产生明显的影响.前人对其消失的原因做出多种解释,但都存在不足.造成这一文明消亡的最重要的原因有二一是人类对自然的过度开发,造成生态环境严重恶化,最终危及文明本身;二是上层建筑发展滞后于经济发展.这种教训对以可持续发展为主旋律的现代社会来说有重要的启示. 相似文献
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在社会主义现代化建设中,充分发挥广大劳动者的积极性是至关重要的,我们应认识到劳动力生产要素在社会生产活动中的主导作用,并承认其与物力资本对等的权力,才能发挥劳动者的主人翁作用,为企业摆脱生产经营困境、改善经营管理和实现国民经济的可持续发展发挥其根本性作用. 相似文献
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Section 1104 of the Administrative Simplification provisions of the Patient Protection and Affordable Care Act (hereafter referred to as the Affordable Care Act) establishes new requirements for administrative transactions that will improve the utility of the existing HIPAA transactions and reduce administrative costs. Specifically, in section 1104(b)(2) of the Affordable Care Act, Congress required the adoption of operating rules for the health care industry and directed the Secretary of Health and Human Services to "adopt a single set of operating rules for each transaction * * * with the goal of creating as much uniformity in the implementation of the electronic standards as possible." This interim final rule with comment period adopts operating rules for two Health Insurance Portability and Accountability Act of 1996 (HIPAA) transactions: eligibility for a health plan and health care claim status. This rule also defines the term "operating rules" and explains the role of operating rules in relation to the adopted transaction standards. In general, transaction standards adopted under HIPAA enable electronic data interchange through a common interchange structure, thus minimizing the industry's reliance on multiple formats. Operating rules, in turn, attempt to define the rights and responsibilities of all parties, security requirements, transmission formats, response times, liabilities, exception processing, error resolution and more, in order to facilitate successful interoperability between data systems of different entities. 相似文献