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141.
创新思维对肾移植模型制作教学的促进作用 总被引:1,自引:0,他引:1
大鼠肾移植模型是研究肾移植排斥反应发生机制、治疗措施以及诱导免疫耐受的重要平台,但其制作复杂,在传统教学中存在诸多问题。对此,我们在教学中充分发挥创新思维,改进了教学方式,建立了多项新技术,显著提高了以显微外科技术为基础的大鼠肾移植模型制作的教学效率与质量,现将体会报告如下。1应用现代教学手段解决传统教学中的难题1.1大鼠肾移植模型的制作特点以及传统教学存在的问题该模型制作主要依赖显微外科技术,教学中,从解剖结构、手术器械到手术操作的突出特点是“精细、微小”,也是教学的难点。传统教学主要依靠文字教材以及部分挂… 相似文献
142.
Upregulation of VEGF and FGF2 in normal rat brain after experimental intraoperative radiation therapy 总被引:3,自引:0,他引:3
The expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF)2 in the irradiated brain was examined to test how a single high dose radiation, similar to that used for intraoperative radiation therapy given to the normal cerebrum, can affect the vascular endothelium. After a burr hole trephination in the rat skull, the cerebral hemisphere was exposed to a single 10 Gy dose of gamma rays, and the radiation effect was assessed at 1, 2, 4, 6, and 8 weeks after irradiation. Histological changes, such as reactive gliosis, inflammation, vascular proliferation and necrosis, were correlated with the duration after irradiation. Significant VEGF and FGF2 expression in the 2- and 8-week were detected by enzyme-linked immunosorbent assay quantification in the radiation group. Immunohistochemical study for VEGF was done and the number of positive cells gradually increased over time, compared with the sham operation group. In conclusion, the radiation injuries consisted of radiation necrosis associated with the expression of VEGF and FGF2. These findings indicate that VEGF and FGF2 may play a role in the radiation injuries after intraoperative single high-dose irradiation. 相似文献
143.
人工髓核材料(半晶聚乙烯醇水凝胶弹性体)的研制 总被引:8,自引:0,他引:8
研制一种可替代椎间盘髓核并恢复其功能的生物医用材料 ,探讨半晶聚乙烯醇水凝胶弹性体材料临床应用的可行性。聚乙烯醇 (PVA)水溶液在 - 2 0℃下冷冻 6~ 12 h,室温下融化 1~ 2 h,上述过程重复 1~ 3次 ,然后对试样进行真空脱水 ,制得人工髓核材料 (半晶 PVA水凝胶弹性体 )。差示扫描量热法 (DSC)和力学性能试验研究了 PVA水溶液浓度、真空脱水和 γ射线辐照对水凝胶 PVA的结晶度和力学性能的影响 相似文献
144.
Guénet JL 《Genome research》2005,15(12):1729-1740
The house mouse has been used as a privileged model organism since the early days of genetics, and the numerous experiments made with this small mammal have regularly contributed to enrich our knowledge of mammalian biology and pathology, ranging from embryonic development to metabolic disease, histocompatibility, immunology, behavior, and cancer. Over the past two decades, a number of large-scale integrated and concerted projects have been undertaken that will probably open a new era in the genetics of the species. The sequencing of the genome, which will allow researchers to make comparisons with other mammals and identify regions conserved by evolution, is probably the most important project, but many other initiatives, such as the massive production of point or chromosomal mutations associated with comprehensive and standardized phenotyping of the mutant phenotypes, will help annotation of the approximately 25,000 genes packed in the mouse genome. In the same way, and as another consequence of the sequencing, the discovery of many single nucleotide polymorphisms and the development of new tools and resources, like the Collaborative Cross, will contribute to the development of modern quantitative genetics. It is clear that mouse genetics has changed dramatically over the last 10-15 years and its future looks promising. 相似文献
145.
取不同年龄组自发性高血压鼠的胸主动脉,颈劝脉和基底动脉,用高效液相色谱-电化学检测仪测定其去甲肾上腺素含量,并取脑软膜血管作超微结构观察,结果显示:各组高血压鼠动有脉壁去甲肾上腺素含量均下降,颈内动脉更明显;脑血管内弹性膜部分断裂,平滑肌细胞有空不包变性等。 相似文献
146.
三维医学图像的分割是计算机辅助诊断与治疗中至关重要的技术。由于现有的三维医学图像分割算法种类繁多且性能各异,对各种分割算法性能公正直观的评价显得尤为重要。我们在对现有常用评价方法做出综合的比较后,提出了一种基于局域距离误差的综合、直观的三维图像分割的新型评价方法,并详细描述了该评价方法中局域误差和全局精确度的评价法。最后,利用这种新型的评价方法对三种常用的分割算法(Fast Marching,Morpholo-gical Reconstruction and Watershed)及一种笔者提出的新型Hybrid算法进行评价,此新型分割算法也在文中作了简要介绍。通过实验,可以验证新的评价方法能够更加科学、直观地对各种三维医学图像分割算法进行评价。 相似文献
147.
In vitro studies of plasma-sprayed hydroxyapatite/Ti-6Al-4V composite coatings in simulated body fluid (SBF) 总被引:2,自引:0,他引:2
The bioactivity of plasma-sprayed hydroxyapatite (HA)/Ti-6Al-4V composite coatings was studied by soaking the coatings in simulated body fluid (SBF) for up to 8 weeks. This investigation was aimed at elucidating the biological behaviour of plasma-sprayed HA/Ti-6Al-4V composite coatings by analyzing the changes in chemistry, and crystallinity of the composite coating in a body-analogous solution. Phase composition, microstructure and calcium ion concentration were analyzed before, and after immersion. The mechanical properties, such as tensile bond strength, microhardness and Young's modulus were appropriately measured. Results demonstrated that the tensile bond strength of the composite coating was significantly higher than that of pure HA coatings even after soaking in the SBF solution over an 8-weeks period. Dissolution of Ca-P phases in SBF was evident after 24h of soaking, and, a layer of carbonate-apatite covered the coating surface after 2 weeks of immersion. The mechanical properties were found to diminish with soaking duration. However, slight variation in mechanical properties was found after supersaturation of the calcium ions was attained with the precipitation of the calcium phosphate layers. 相似文献
148.
Diagnostic performance of the Roche AMPLICOR PCR in detecting Neisseria gonorrhoeae in genitourinary specimens from female sex workers in Cotonou, Benin 总被引:3,自引:0,他引:3 下载免费PDF全文
Mukenge-Tshibaka L Alary M Bernier F van Dyck E Lowndes CM Guédou A Anagonou S Joly JR 《Journal of clinical microbiology》2000,38(11):4076-4079
The objective of this study was to evaluate the diagnostic performance of the Roche multiplex AMPLICOR Chlamydia trachomatis/Neisseria gonorrhoeae PCR test for the detection of Neisseria gonorrhoeae infection in female urine specimens and wet and dry endocervical swabs. Endocervical swabs and urine specimens were collected from 342 female sex workers from Cotonou, Benin, and were tested using the AMPLICOR C. trachomatis/N. gonorrhoeae test (Roche Diagnostic Systems, Inc., Branchburg, N.J.) with internal control detection. Endocervical swabs were also cultured on Thayer-Martin medium. A series of alternate standards that included a combination of all the tests but not the test being evaluated was used to assess the performance of the test with each type of specimen. The sensitivity, specificity, and positive and negative predictive values for the urine were 53.8, 98.9, 93.5, and 87.5%, respectively. Corresponding figures for the wet swab were 91.5, 100, 100, and 97.4%, respectively. Those for the dry swab were 96.3, 96.2, 88.5, and 98.8%, respectively. Based on this study, the AMPLICOR PCR assay showed a low sensitivity for detection of N. gonorrhoeae infection in urine specimens, whereas the test was found to be highly sensitive and specific with endocervical specimens. 相似文献
149.
Linkage studies have identified a large (>60-Mb) region on chromosome 10q that segregates with Alzheimer Disease (AD). Within the region, the gene for insulin degrading enzyme (IDE) represents a notable biological candidate given that it degrades amyloid beta-protein (one of the major constituents of senile plaques) and the intracellular amyloid precursor protein (APP) domain released by gamma-secretase processing. We have used a single nucleotide polymorphism (SNP) genetic association strategy to investigate AD in relation to a 480-kb region encompassing IDE. A 276-kb linkage disequilibrium block was revealed that spans three genes (IDE, KNSL1, and HHEX). Assessing this block in several independent sets of case-control materials (early- and late-onset AD) and focusing also upon quantitative measures that are pertinent to AD diagnosis and severity (MMSE scores, microtubule-associated protein Tau [MAPT] levels in CSF, degree of brain pathology, and age-at-onset) produced extensive evidence for significant AD association. Signals (p-values ranging from 0.05 to <1x10(-9)) were generally stronger when examining haplotypes rather than individual SNPs, and quantitative trait tests most uniformly revealed the detected associations. Consistent risk alleles and haplotypes were apparent across the study, with effects in some cases as large as that of the epsilon4 allele of APOE. A subsequent mutation screen of exons in all three suspect genes provided no evidence for common causative mutations. These results provide substantial evidence that genetic variation within or extremely close to IDE impacts both disease risk and traits related to the severity of AD. 相似文献
150.
以人应激和分子伴侣蛋白(STCH)为诱饵蛋白,利用酵母双杂交技术在高严格条件下筛选人脑cDNA文库。在SD/-4培养基上共获得156个阳性克隆,将酵母菌扩增后抽提质粒,转化大肠杆菌,进行序列分析,并经过回复杂交验证,潜在的与STCH相互作用的蛋白有:VDAC、MBP2、ZNF251、RanBP9、Phosophate glycolase、β-tubulin、up1、up2和WW adaptor蛋白。基于各候选蛋白与神经系统疾病的关系,选择RanBP9作进一步验证实验。经体外GST-Pulldown和体内免疫共沉淀实验证实RanBP9和STCH能够相互作用,明确RanBP9的羧基端为相互作用的最小功能域。此结果为我们进一步揭示STCH作用的分子机制提供了线索。 相似文献