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131.
Bone-particle-impregnated bone cement: an in vivo weight-bearing study   总被引:2,自引:0,他引:2  
To evaluate an experimental inorganic-bone-particle-impregnated bone cement, canine hip prostheses were implanted in dogs using a regular bone cement on one side and the experimental bone cement on the other. In a preliminary feasibility study, bone ingrowth into the resorbed bone-particle spaces was established 3 months after implantation in three dogs. In a more detailed study, twenty-eight (28) dogs were divided in four groups to delineate the effects of time on the phenomena of bony ingrowth. One month after implantation, active bone ingrowth into the bone cement was obvious. By 3 months postimplantation, the ingrowth appeared to have traversed the thickness of the bone-particle-impregnated cement. By the fifth month, most of the interconnected inorganic bone particles were replaced by new bone. At the end of a year, the ingrown bone was mature and negligible new bone activity was present. Biomechanical pushout tests closely corroborated the histologic observations. The maximum shear strength of the cement/bone interface of the experimental side reached 3.6 times that of the control side at 5 months postimplantation. No further improvements were seen at 12 months postimplantation. A viable bone/cement interface may result in a better orthopedic implant fixation system by combining the advantages of both cement for immediate rigidity and biological ingrowth for longterm stability.  相似文献   
132.
目的:探讨在精神科住院病人中异质性团体治疗的运用。方法:收集不同诊断的住院病人,分析精神科住院病人团体治疗的组成、创建,并通过案例报告探讨治疗过程。结果:团体的开放性、异质性、隐私性和疗效评价是评价团体治疗的重要因素。结论:可以在中国精神科住院病人中推广团体治疗。  相似文献   
133.
The effects of histamine on the spontaneous activity of the isolated human myometrium were studied. Both the frequency and force of contractions of the muscle strips were not significantly altered by histamine. The presence of either a histamine H1-or H2-receptor antagonist in the organ bath did not significantly change the responses of the uterine muscle to histamine. These findings suggest that histamine has negligible effects on the human myometrium, possibly due to the absence, or paucity, of histamine receptors.  相似文献   
134.
下丘脑分泌的促甲状腺激素释放激素(Thyrotropin—releasing hormone,TRH)促进垂体促甲状腺激素(Thyrotropin,TSH)的合成和释放,而多巴胺(Dopamine,DA)和生长抑素(Somatostatin,SST)抑制TSH的合成和释放,甲状腺激素也对TSH产生反馈抑制作用。甲状腺功能减退患者,伴随多巴胺能神经元功能(Dopaminergietone)的降低和TSH基础水平升高。胃复安(Metoclopramide,MCP)是多巴胺第二受体拮抗剂,能加速提高甲低患者血TSH水平,特别是当运用于分化型甲癌(Differentiated thyroid carcinoma,DTC)病人时,能缩短停用左旋甲状腺素(L—thyroxine,L—T4)的时间和减轻甲状腺机能减退所致的症状和体征,有助于对DTC病灶的^131I显像诊断和^131I治疗。  相似文献   
135.
The glutamate pathways are involved in diverse processes such as learning and memory, epilepsy, and they play important roles in neural plasticity, neural development, and neurodegeneration. It has been proposed that autism could be a hypoglutamatergic disorder. Recently, Jamain et al. reported that the glutamate receptor 6 (GluR6 or GRIK2) is in linkage disequilibrium with autism. In the present study, the transmission disequilibrium test (TDT) and the haplotype transmission were performed to analyze the four SNPs (SNP1: rs995640; SNP2: rs2227281; SNP3: rs2227283; SNP4: rs2235076) of GluR6 in 174 Chinese Han parent-offspring trios. The TDT demonstrated that the two SNPs (SNP2 and SNP3) showed preferential transmission (TDT P = 0.032). The global chi(2) test for haplotype transmission also revealed an association between GluR6 and autism (chi(2) = 10.78, df = 3, P = 0.013). Our results suggested that GluR6 is in linkage disequilibrium with autism.  相似文献   
136.
137.
Dai J  Zhu Y  Ji Q 《Medical physics》2000,27(12):2757-2762
This study introduces a new concept, the super-omni wedge, and proposes an algorithm for optimizing beam weights, wedge angles, and wedge orientations on the basis of this new concept. The super-omni wedge is a generalization of the omni wedge. Instead of combining one open beam and two orthogonal wedged beams, it uses two orthogonal pairs of nominal wedged beams to generate a wedged dose distribution with an arbitrary wedge angle and an arbitrary wedge orientation. The orientations of a pair of nominal wedges are opposite each other. In this way, the effective wedge orientation can vary from 0 degrees to 360 degrees rather than being restricted to one quadrant. When the concept of the super-omni wedge is used, the optimization of beam weights, wedge angles, and wedge orientations for J beams is transformed into the optimization of beam weights for 4J beams. A quadratic dose-based objective function is defined, and the method of sequential quadratic programming is used to find the 4J beam weights that minimize it. After the weights of the nominal wedged beams have been determined, the beams can be delivered in one of four methods: Directly, by using the omni wedge technique, by using the universal wedge technique, and by using the virtual wedge technique. When tested with two clinical cases, the algorithm achieved homogeneous dose distributions in target volumes while meeting the constraints to the organs at risk. A prominent feature of the algorithm is that there is no need to manually preselect the orientations of nominal wedges.  相似文献   
138.
目的:探讨颈内动脉岩内段形态位置变化的规律及其与毗邻结构的关系.方法:对66侧正常成人颅底高分辨率CT连续图像进行分析,测量颞骨气房体积,建立定位颈内动脉岩内段及其毗邻结构的参照系,对其位置和形态进行测量,运用偏相关分析方法求出它们形态位置的变化规律及其影响因素.结果:在男性,颈内动脉垂直段更偏外侧,其水平段长度也大于女性.颞骨气化好,则颈内动脉垂直段更偏后移.颈内动脉垂直段与颈静脉球的位置变化表现为同步.垂直段的内外移位相应地使水平段与中线的夹角发生变化.颈内动脉水平段的方位与蜗轴方向相关,蜗轴偏离中线的角度越小,则颈内动脉水平段偏离中线的角度越大,反之亦然.结论:影响颈内动脉岩内段形态位置变化的因素是复杂和多重的,包括性别因素、颅底发育状态、颞骨气化程度以及毗邻结构发育状态均可能是影响因素.  相似文献   
139.
目的:观察犬冠状动脉左旋支狭窄后心肌细胞对^99碍^m-甲氧基异丁基异腈(^99Tc^m-MIBI)摄取与时间变化之间的关系。方法:建立犬冠状动脉左旋支狭窄模型(12只),分别注射^99Tc^m-MIBI,剂量为185MBq(5mCi)。注射1h和4h后,各处死6只犬,取出心脏,于左室侧壁(缺血区)和前壁(正常区)分别取心肌组织约100rag,用1计数器测定其放射性计数,换算成每克组织放射性计数值,求出侧壁与前壁放射性比值。结果:注射后1h犬左心室缺血区与正常区组织放射性计数比值为0.726±O.054,4h为0.673±0.080,两者之间比较差鼻无昂薯件(t=1.3452.P〉0.05).结论.砸长时问不能摇高按血心肌对辨^99Tc^m-MIBI梧取比.  相似文献   
140.
以21例Ⅱ期高血压患者、21例Ⅱ期高血压病高胰岛素血症患者及20例正常人为研究对象,以全血比粘度、全血还原比粘度、血浆比粘度、红细胞压积及血浆甘油三酯、总胆固醇、高密度脂蛋白为指标;结果表明Ⅱ期高血压病患者全血比粘度、全血还原比粘度较正常人高,Ⅱ期高血压病高胰岛素血症患者亦较单纯高血压病患者进一步增高,同时其血浆甘油三酯较单纯高血压病患者增高,高密度脂蛋白降低.而血浆比粘度、红细胞压积、总胆固醇三组间无显著性差异。单纯高血压病患者与正常人组比较血脂无差异。因而认为高血压病患者的高胰岛素血症可使高血压病患者增高的血粘度进一步增高,且血粘度的增高主要是红细胞机能、代谢的改变所致。单纯高血压病患者血脂改变不明显,高血压病患者血脂的改变主要是由高胰岛素血症所致。  相似文献   
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