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21.
Pilar Nicolás 《Hereditary cancer in clinical practice》2007,5(3):144-152
The specific characteristics of genetic data lead to ethical-legal conflicts in the framework of genetic diagnosis. Several international organisations, including UNESCO and the Council of Europe, have enacted rules referring to the use of genetic information. This paper discusses possible legal and ethical criteria that could be used in genetic testing. 相似文献
22.
腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析 总被引:1,自引:0,他引:1
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。 相似文献
23.
Population-based association studies are powerful tools for the genetic mapping of complex diseases. However, this method is sensitive to potential confounding by population structure. While statistical methods that use genetic markers to detect and control for population structure have been the focus of current literature, the utility of self-defined race/ethnicity in controlling for population structure has been controversial. In this study of 1334 individuals, who self-identified as either African American, European American or Hispanic, we demonstrated that when the true underlying genetic structure and the self-defined racial/ethnic groups were roughly in agreement with each other, the self-defined race/ethnicity information was useful in the control of population structure. 相似文献
24.
纸本与数字的交互:手机阅读的最佳效果 总被引:1,自引:0,他引:1
顾璟 《南通大学学报(哲学社会科学版)》2008,24(6):137-140
随着全球3G商用的推进和拥有大容量存储能力的智能终端的日益普及,手机正逐步演变成为一个新型的数字阅读终端。利用手机进行电子阅读的全新模式,正以前所未有的普及速度冲击着人们的阅读习惯。而这趋势也逐渐为"阅读"进行重新的定义。对于每一个读者而言,在这样一个信息化的时代里,手机阅读和纸本阅读的交互使用、取长补短,才是获得最佳阅读效果的最有效方式。 相似文献
25.
F. Specchiulli R. Gabrieli D. Borsetti V. Di Carlo 《Journal of orthopaedics and traumatology》2007,8(3):123-127
We examined the clinical and radiographic results of 93 patients affected by knee arthritis or osteonecrosis subjected to
unilateral cementless mobile-bearing total knee arthroplasty with the LCS prothesis (Depuy/Johnson & Johnson). The mean follow-up
was 9.5 years (range, 7–12 years). Clinical evaluation was performed using the Knee Society rating system, while radiographic
evaluation was done according to the Knee Society roentgenographic system. At the latest follow-up, the mean knee score was
87 points: the functional score improved from 40 to 90. Radiolucent lines were small and not progressive. The implant survival
at 12 years was 88%. Six knees (7%) required revision for implant-related problems. We conclude that the mobile-bearing prosthesis
is a successful device even at long-term follow-up. 相似文献
26.
目的:研究载脂蛋白E(ApoE)基因多态性与颈动脉粥样硬化的相关性。方法:应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)技术,对25例B超检测颈动脉内中膜厚度(IMT)增厚患者(增厚组)和25例同期健康体检者(对照组)的ApoE基因多态性进行分析。结果:IMT增厚组ε3等位基因频率较对照组降低(P<0.05),ε4等位基因频率较对照组升高(P<0.01)。IMT增厚组的ε3/ε4基因型频率显著要高于对照组。对以上两组再按ApoE基因型分别分为3组:ApoE2(ε2/2 ε2/3),ApoE3(ε3/3)和ApoE4(ε3/4 ε4/4)。结果显示颈动脉IMT在不同基因型间差异显著,ApoE4组显著增加,颈动脉多发斑块率在此组也显著增加。结论:ApoE基因多态性与颈动脉粥样硬化形成有相关性,ε4基因是颈动脉粥样硬化形成的危险因子。 相似文献
27.
Hui-Ju Wen Ying-Chu Lin Yung-Ling Lee Yueliang Leon Guo 《Pediatric allergy and immunology》2006,17(7):489-494
High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha. 相似文献
28.
铰链式冠外附着体的结构强度分析 总被引:2,自引:0,他引:2
目的探讨铰链式冠外附着体设计的合理性.方法采用有限元应力分析的实验方法,分析铰链式冠外附着体阳性结构L形球体的应力分布情况,对其结构强度进行测试.结果在附着体阳性结构L形球体的转角处应力最大,应力值为321.847MPa.结论该铰链式附着体的结构强度符合临床设计要求. 相似文献
29.
本系统通过以Internet网为平台,将传统的医院/患者(咨询者)的遗传随访模式转为医院/Internet网/患者(咨询者)的新医疗模式,该系统会大大提高遗传随访的及时性和便利性;同时,会有利于遗传登记的开展,也有利于随访资料的保存。 相似文献
30.
S. D. ROBINSON† C. A. LUDLAM‡ N. A. BOON† D. E. NEWBY† 《Journal of thrombosis and haemostasis》2006,4(10):2262-2269
OBJECTIVES: To determine if polymorphisms of the tissue plasminogen activator (t-PA) gene influence acute endogenous t-PA release in patients with coronary heart disease (CHD). METHODS: Forearm blood flow and plasma t-PA concentrations were measured in response to intra-brachial infusion of substance P and sodium nitroprusside in 96 patients with stable CHD. Genotyping was performed using a Taqman polymerase chain reaction assay specifically designed to detect the polymorphisms of interest: (i) Alu-repeat insertion/deletion sequence; (ii) C-->T substitution in an upstream enhancer region (-7351 C/T); (iii) T-->C in exon 6 (20 099 T/C); and (iv) T-->A (27 445 T/A) in intron 10. RESULTS: Substance P and sodium nitroprusside caused dose-dependent increases in forearm blood flow in all patients (P < 0.001 for all) that were independent of the four genetic polymorphisms. Similarly, there were no differences in basal plasma t-PA antigen concentrations or net t-PA release between genotypes. Compared to non-smokers, smokers exhibited impaired substance P-induced vasodilatation (P < 0.001) and t-PA release (P = 0.05). CONCLUSIONS: Despite confirming our previous findings in cigarette smokers, we have found no effect of polymorphisms of the t-PA gene on two complementary aspects of endothelial function. We conclude that genetic variation of the t-PA locus is unlikely to have a major influence on acute t-PA release in subjects with established CHD. 相似文献