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991.
计算机辅助全膝置换中股骨力线定位精度的实验研究   总被引:3,自引:0,他引:3  
摘要利用光学定位追踪仪确定全膝置换中患者的股骨头中心从而确定其股骨力线,在力线的定位精度分析中,首次采用股骨的三维重建模型进行精度校验。实验结果表明通过追踪固定于股骨末端的刚性定位器即能确定精确的股骨力线,与传统的髓内定位相比,不仅可重复性好,而且大大地提高了术中股骨力线的位置精度,将其位置偏差减小到10以内。  相似文献   
992.
Fu AL  Li Q  Dong ZH  Huang SJ  Wang YX  Sun MJ 《Neuroscience letters》2004,368(3):258-262
Much evidence indicates that the memory and cognitive deficits of patients with Alzheimer's disease are closely associated with dysfunction of central cholinergic system. The degree of reduction of choline acetyltransferase activity in cerebral cholinergic neurons is significantly correlated with the severity of dementia or cognitive impairments observed in Alzheimer's disease. Therefore, Alzheimer's disease may be slowed by supplementation of exogenous choline acetyltransferase. Here we show that choline acetyltransferase mediated by TAT protein transduction domain passes through the blood-brain barrier and enters the neurons in mice, increasing choline acetyltransferase and neurotransmitter acetylcholine contents. The recombination TAT-choline acetyltransferase fusion protein injected intravenously improves the memory and cognitive dysfunction in Alzheimer's disease model mice induced by amyloid-beta peptide. Our results imply a novel and potentially effective way for Alzheimer's disease therapy.  相似文献   
993.
Summary: Novel temperature sensitive poly(N‐isopropylacrylamide‐co‐acryloyl beta‐cyclodextrin) (P(NIPA‐co‐A‐CD)) hydrogels with fast shrinking rates were prepared by radical polymerization of NIPA, A‐CD and crosslinker in a mixture of water/1,4‐dioxane as solvent. Because the mixed solvent was a poor solvent for the copolymers, phase separation occurred during the polymerization, which resulted in a heterogeneous, porous structure of the hydrogels. In contrast to the normal PNIPA hydrogel and the homo P(NIPA‐co‐A‐CD) gel prepared in water, the P(NIPA‐co‐A‐CD) hydrogels synthesized in water/1,4‐dioxane as solvent exhibited higher swelling ratios at the temperature below the lower critical solution temperature (LCST) and shrunk rapidly to equilibrium within shorter time when the temperature was increased above LCST. Increasing the acryloyl beta‐cyclodextrin content in the gels led to a slight decrease of the swelling ratio at lower temperature and had no marked influence on the shrinking kinetics. The gels prepared in water/1,4‐dioxane, at different v/v ratios of 1.0/0.2, 0.8/0.4 and 0.6/0.6, showed similar properties.

SEM photos of the heterogeneous P(NIPA‐co‐A‐CD) hydrogel prepared in water/1,4‐dioxane.  相似文献   

994.
健康教育对早产低体重儿的影响   总被引:1,自引:0,他引:1  
目的 了解整体护理健康教育对早产低体重儿的影响,寻找有效的健康教育方法。方法 对2000年1月至2001年9月在新生儿病区住院早产儿随机分为干预组和对照组;干预组除住院期间给予常规护理外,还在出院后对其家长进行健康指导,方法包括;早产儿出院时的直接指导,派发资料,电话咨询,上门指导等;对照组只在住院期间给予常规护理,出院后不作干预指导,结果 干预组的母乳喂养率较对照组明显高。而患病率则明显低,经统计学分析有显著性差异。结论 通过健康指导,家长获得科学的育儿知识,逐渐掌握早产儿的护理,育儿水平得以提高,利于早产儿健康成长。  相似文献   
995.
Qin C  Wang J  Wei Q  She M  Marasco WA  Jiang H  Tu X  Zhu H  Ren L  Gao H  Guo L  Huang L  Yang R  Cong Z  Guo L  Wang Y  Liu Y  Sun Y  Duan S  Qu J  Chen L  Tong W  Ruan L  Liu P  Zhang H  Zhang J  Zhang H  Liu D  Liu Q  Hong T  He W 《The Journal of pathology》2005,206(3):251-259
A new SARS animal model was established by inoculating SARS coronavirus (SARS-CoV) into rhesus macaques (Macaca mulatta) through the nasal cavity. Pathological pulmonary changes were successively detected on days 5-60 after virus inoculation. All eight animals showed a transient fever 2-3 days after inoculation. Immunological, molecular biological, and pathological studies support the establishment of this SARS animal model. Firstly, SARS-CoV-specific IgGs were detected in the sera of macaques from 11 to 60 days after inoculation. Secondly, SARS-CoV RNA could be detected in pharyngeal swab samples using nested RT-PCR in all infected animals from 5 days after virus inoculation. Finally, histopathological changes of interstitial pneumonia were found in the lungs during the 60 days after viral inoculation: these changes were less marked at later time points, indicating that an active healing process together with resolution of an acute inflammatory response was taking place in these animals. This animal model should provide insight into the mechanisms of SARS-CoV-related pulmonary disease and greatly facilitate the development of vaccines and therapeutics against SARS.  相似文献   
996.
997.
998.
Crescentic glomerulonephritis (GN) demonstrates immunopathological features of a T helper (Th)1-directed delayed-type hypersensitivity (DTH) response. The capacity of Th2 cytokines to attenuate crescentic glomerular injury in this disease was examined by administering interleukin (IL)-4 and IL-10, singly and in combination. GN was induced by i.v. administration of sheep anti-mouse glomerular basement membrane (GBM) globulin to mice sensitized to sheep globulin 10 days earlier. Treatment (2.5 μg, i.p.) with IL-4, IL-10, or both IL-4 and IL-10 (IL-4+10), was started 1 h before sensitization and continued daily until the end of the study (10 days after administration of anti-GBM globulin). Control mice treated with PBS developed GN with glomerular accumulation of T cells and macrophages, crescents in 42.5 ± 4.5 % of glomeruli (normal 0 %), proteinuria (8.3 ± 0.9 mg/24 h, normal 0.74 ± 0.08 mg/24 h, p < 0.001) and renal impairment (creatinine clearance [cr/cl]: 93 ± 12 μ1/min, normal 193 ± 10 μ1/min, p<0.001). 1reatment with either IL-4, IL-10, or IL-4+10 prevented crescent formation (crescentic glomeruli: 0.8 ± 0.5, 1.2 ± 0.9, and 1.4 ± 1.0 %, respectively, all p<0.01 compared to control) and attenuated proteinuria (3.6 ± 1.0, 2.2 ± 0.5, and 2.9 ± 0.5 mg/24 h, respectively, all p<0.01 compared to control). IL-4+10 prevented development of renal impairment (cr/cl: 183 ± 22 μ1/min); IL-10 given alone limited the decline in renal function (cr/cl: 150 ± 20 μ1/min), but IL-4 alone did not provide any significant protection (cr/cl: 121 ± 17 μ1/min). All treatments markedly diminished glomerular T cell and macrophage accumulation, reduced interferon-γ production by splenic T cells, prevented cutaneous DTH to the disease-initiating antigen and reduced antigen-specific immunoglobulin of the IgG2a and IgG3 isotypes. These data demonstrate that crescentic GN and renal impairment can be prevented by administration of Th2 cytokines and that this effect is associated with attenuation of the Th1 response to the disease-initiating antigen.  相似文献   
999.
四种脊椎动物血细胞亚显微结构的比较观察   总被引:9,自引:0,他引:9  
颜桂利  黄键 《解剖学报》1996,27(1):100-103
用透射电镜观察了罗非鱼、虎纹蛙、家鸽和家兔各类血细胞的亚显微结构、结果表明:鱼、蛙。鸽的红细胞呈长椭圆形、长梭形或长橄榄形,有核,核周异染色质明显:而兔的红呈两面凹陷的圆盘状、无核、胞内充满血红蛋白、鱼、蛙、鸽血中尚见到血栓细胞,其形状与红细胞相似,体积较小,胞核较大;兔血小板呈不规则形,无核。鱼、蛙、鸽、兔的白细胞,形状结构基本相似,除能见到核和细胞器之外,胞质内的特殊颗粒以及细胞伸出的伪足、微  相似文献   
1000.
肾移植取肾方法的改进   总被引:1,自引:0,他引:1  
报道了自1985年2月至今共摘取供肾132例,取得尸肾263只(1例独立肾),其中251只供肾用于临床。分侧切取肾38例,整块切肾41例,改进后整块切肾53例。文中着重介绍改进后的整块切取尸肾的手术方法,讨论了术式的优缺点。  相似文献   
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