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71.
J Goldhahn M Reinhold M Stauber C Knop R Frei E Schneider B Linke 《Journal of orthopaedic research》2006,24(5):917-925
The goal of our study was to evaluate two newly developed implant designs and their behavior in terms of subsidence in lumbar vertebral bodies under cyclic loading. The new implants were evaluated in two different configurations (two small prototypes vs. one large prototype with similar load-bearing area) in comparison to a conventional screw-based implant (MACS TL). A pool of 13 spines with a total of 65 vertebrae was used to establish five testing groups of similar bone mineral density (BMD) distribution with eight lumbar vertebrae each. In additional to BMD assessment via dual-energy X-ray absorptiometry, cancellous BMD and structural parameters were determined using a new generation in vivo 3D-pQCT. The specimens were loaded sinusoidally in force control at 1 Hz for 1000 cycles at three load levels (100, 200, and 400 N). A survival analysis using the number of cycles until failure (Cox regression with covariates) was applied to reveal differences between implant groups. All new prototype configurations except the large cylinder survived significantly longer than the control group. The number of cycles until failure was significantly correlated with the structural parameter Tb.Sp. and similarly with the cancellous BMD for three of five implants. In both large prototypes the cycle number until failure significantly correlated with the preoperative distance to the upper endplates. Although the direct relationship between bone structure or density and mechanical breakage behavior cannot be conclusively proven, all the prototypes adapted for poor bone structure performed better than the comparable conventional implant. 相似文献
72.
Laying hens are very efficient producers of antibodies and provide an interesting alternative for large-scale production of specific antibodies. These antibodies also have biochemical advantages over mammalian antibodies (e.g. rabbit antibodies) that can be used to improve immunoassays where antibodies are used. The concentration of IgY in egg yolk is an important production parameter. The purpose of this study was to investigate the genetic variation of IgY levels in egg yolk. We have compared IgY concentrations in egg yolks from two lines, selected for egg production traits at the Swedish University for Agricultural Sciences (Single Comb White Leghorn and Rhode Island Red) and a cross between the two lines (SLU-1392). Single Comb White Leghorns have the highest mean concentration of yolk IgY, 2.21 mg ml-1 compared to SLU-1392 1.95 mg ml-1 and Rhode Island Red 1.68 mg ml-1. The cross thus had an intermediate IgY concentration in relation two the two other lines. There were great differences between individual animals within each line. Our results indicate that it should be possible to increase yolk antibody production by using a high producing chicken line and by genetic selection within the line. We found three individuals with very low yolk IgY concentrations among the Rhode Island Red hens. Newly hatched chickens with limited amounts of IgY from the hen may be more susceptible to infections. 相似文献
73.
抗CD25抗体预防移植物抗宿主病在儿童白血病半匹配骨髓移植中的应用 总被引:1,自引:0,他引:1
目的 探讨抗 CD2 5抗体用于预防儿童白血病半匹配未去 T细胞骨髓移植重度移植物抗宿主病 (GVHD)的疗效。 方法 10例儿童白血病患者接受 HL A2 - 3位点不合半匹配骨髓移植 ,移植方法除了供者应用粒细胞集落刺激因子 (GCSF)2 5 0μg促进骨髓及受者应用环孢素 A(CSA ) ,甲氨蝶呤 (MTX) ,抗胸腺细胞球蛋白 (ATG)和霉酚酸酯 (MMF)预防 GVHD综合措施外 ,加用抗 CD2 5单克隆抗体预防 GVHD,剂量各为 2 0 m g,在移植前 2 h和移植后第 4天应用 ,采髓后未去 T细胞输注 ,移植结果与前期未用 Simulect移植组比较。 结果 10例移植后均获造血重建 ,粒细胞大于 0 .5× 10 9/ L 中位天数是19 d,血小板大于 2 0× 10 9/ L 的中位天数是 2 2 d,骨髓植活直接证据检测证实为完全供者造血。无 1例发生急性 ~ GVHD,未用 Sim ulect对照组急性 ~ GVHD为 5 0 % ,差异有显著性意义。可评价慢性 GVHD的 8例均发生慢性 GVHD,均为局限性慢性 GVHD。中位随访 12个月 (范围 9~ 2 4个月 ) ,2例移植相关死亡 ,1例移植后 14个月复发死亡 ,实际无病生存率是 70 % ,与对照比较差异无显著性意义。 结论 本研究儿童半匹配未去 T细胞骨髓移植应用 Sim ulect,明显降低急性重症 a GVHD发生 ,减少移植相关死亡 ,临床应用安全可行。 相似文献
74.
潮汕地区健康青年H9、H6、H5亚型甲型流感病毒血清抗体调查 总被引:7,自引:0,他引:7
目的:调查潮汕地区健康青年中H9、H6、H5三种甲型流感病毒亚型的隐性感染情况,以期了解上述三种禽类甲型流感病毒亚型是否能够或已经从禽类直接或间接传染给人。方法:潮汕地区健康青年血清946份,通过HI实验进行抗体检测。结果:H9亚型抗体阳性率达37.2%;同时发现有三份血清存在H5抗体;未见H6亚型抗体的存在。结论:H9亚型在健康青年中的隐性感染率非常高;H5亚型抗体的存在也应值得注意。 相似文献
75.
A monoclonal antibody to the molluscan small cardioactive peptide SCPB and a polyclonal antibody to FMRFamide were used to localize antigens in the stomatogastric nervous system and brain of two species of Cancer. Both antibodies labeled cell bodies, axons, and neuropilar processes in the brain and in the stomatogastric nervous system. All of the SCPB immunoreactive neurons were co-labeled with antibody to FMRFamide. However, antibody to FMRFamide labeled additional neurons of the commissural ganglion and the brain that were not immunoreactive to the monoclonal SCPB antibody. 相似文献
76.
Twenty-one normal young male subjects underwent resting and exercise (bicycle) radionuclide angiography in the full supine and 70 degrees upright tilt positions in order to examine the effects of position on left ventricular size and performance, hemodynamics, and exercise duration. All subjects also underwent full (90 degrees) upright bicycle ergometry with respiratory gas analysis to establish the level of maximal exercise capacity for each. Body position significantly (p less than 0.05) affected resting and exercise cardiovascular parameters. End-diastolic and endsystolic left ventricular volumes and stroke volume were larger in the supine position, both at rest and during exercise. The cardiac output at rest and during exercise were comparable for the two positions; an increase in resting and exercise heart rate in the 70 degrees tilt position compensated for the reduced stroke volume of this posture. At maximal exercise, the 70 degrees upright position was associated with a greater response in left ventricular ejection fraction, otherwise this parameter was not position related. Exercise capacity, in terms of duration and workload, was significantly higher in the supine (1870 +/- 390 s) and full upright (1830 +/- 250 s) positions than in the 70 degrees tilt position (1730 +/- 260 s). Changes in body position significantly alter parameters of ventricular, cardiovascular, and exercise performance. 相似文献
77.
78.
目的 为了掌握西安市婴儿麻疹疫苗 (以下简称MV)基础免疫接种情况 ,以进一步提高免疫成功率。方法 在西安市城区和郊区随机抽查 5 7名 0岁组健康婴儿 ,采用酶联免疫吸附法 (ELISA)测定血清麻疹IgG抗体水平。结果 免疫前MV阳性率为 2 8 0 7% ,GMT 1∶4;免疫后MV阳性率为 98 2 5 % ,GMT 1∶1666;免疫前后阳性率、抗体平均滴度经统计分析 ,差异有非常显著性 (P <0 .0 1) ;对MV免疫后不同性别、不同地区的抗体阳性率 ,平均滴度进行统计分析 ,差异无显著性 (P >0 0 5 )。结论 婴儿在出生后 8个月 ,母体胎传抗体逐渐衰减 ,致MV阳性率极低 ,只需按现行的免疫程序及时有效地接种MV ,就能获得保护抗体 ,达到控制麻疹发病的目的。同时也说明MV的免疫成功与否不受性别和地区的影响。 相似文献
79.
David A Grimes J David Grimes Lem Racacho Kylie A Scoggan Fabin Han Betty Anne Schwarz John Woulfe Dennise Bulman 《Movement disorders》2002,17(6):1205-1212
The identification of rare, large families with Parkinson's disease (PD) has provided important clues that have contributed to our understanding of this complex disorder. We have identified a large French-Canadian kindred that spans five generations consisting of more than 90 individuals. A total of 65 individuals now have been examined, had venous blood drawn, and DNA extracted. Two-point and multipoint linkage analysis was performed to assess linkage to known PD genes or loci. Within the third and fourth generations of this family there are 10 living, plus 3 deceased members with well-documented levodopa responsive parkinsonism. Autopsy results on 1 member demonstrated the loss of pigmented neurons in the substantia nigra and the presence of alpha-synuclein positive Lewy bodies. Four of the PD patients have prominent postural and kinetic tremors that preceded their parkinsonism by up to 10 years. Two other individuals within the family have prominent isolated postural and kinetic tremors without parkinsonism. The alpha-synuclein(4q21.3-23), Parkin(6q25.2-27), PARK3 (2p13), PARK4, and ubiquitin carboxy terminal hydrolase-L1 (4p14-16.3) and PARK6 and PARK7 (1p35-36) loci were excluded in this kindred using closely linked markers. The clinical and pathological features of this family are consistent with the diagnosis of PD. This family further demonstrates the known genetic heterogeneity in PD and is large enough that a genome-wide screen has been undertaken in an effort to identify a novel PD gene. 相似文献
80.
Abstract: The identification of familial breast cancer genes heralds an era of directed breast cancer treatment. Currently, two hereditary breast cancer genes have been identified, BRCA-1 and BRCA-2 . Although accounting for only approximately 5% of all breast cancers, they are being used to identify women with germ-line alterations that are at high risk of developing breast or ovarian cancer. With the identification of such genes comes a need for consideration of the ethical issues associated with testing. These genes are also being examined from a biochemical standpoint encompassing both their biological roles and biochemical pathways in which they reside. Such studies are likely to lead to novel breast cancer therapies. 相似文献