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991.
目的:介绍一种基于小波变换和拉普拉斯算子的血液细胞图像边缘识别方法。材料和方法:取正常人血样5mL。制成血液细胞图片12片,对血图像进行预处理后,利用小波变换的多分辨率特性滤除细胞图像中的干扰成份。根据血液细胞边缘附近的灰度分布梯度较大的特点,采用拉普拉斯算子及双阈值法对其进行边缘检测和识别。结果和结论:实验结果表明,结合小波变换和拉普拉斯算子的边缘提取算法对血液细胞图像边缘提取有良好的效果.为下一步对血液细胞的形态学分析、分类和识别提供了新途径。 相似文献
992.
Herpesviruses in brain and Alzheimer's disease 总被引:1,自引:0,他引:1
It has been established, using polymerase chain reaction (PCR), that herpes simplex virus type 1 (HSV1) is present in a high proportion of brains of elderly normal subjects and Alzheimer's disease (AD) patients. It was subsequently discovered that the virus confers a strong risk of AD when in brain of carriers of the type 4 allele of the apolipoprotein E gene (apoE-epsilon4). This study has now sought, using PCR, the presence of three other herpesviruses in brain: human herpesvirus 6 (HHV6)-types A and B, herpes simplex virus type 2 (HSV2) and cytomegalovirus (CMV). HHV6 is present in a much higher proportion of the AD than of age-matched normal brains (70% vs. 40%, p=0.003) and there is extensive overlap with the presence of HSV1 in AD brains, but HHV6, unlike HSV1, is not directly associated in AD with apoE-epsilon4. In 59% of the AD patients' brains harbouring HHV6, type B is present while 38% harbour both type A and type B, and 3% type A. HSV2 is present at relatively low frequency in brains of both AD patients and normals (13% and 20%), and CMV at rather higher frequencies in the two groups (36% and 35%); in neither case is the difference between the groups statistically significant. It is suggested that the striking difference in the proportion of elderly brains harbouring HSV1 and HSV2 might reflect the lower proportion of people infected with the latter, or the difference in susceptibility of the frontotemporal regions to the two viruses. In the case of HHV6, it is not possible to exclude its presence as an opportunist, but alternatively, it might enhance the damage caused by HSV1 and apoE-epsilon4 in AD; in some viral diseases it is associated with characteristic brain lesions and it also augments the damage caused by certain viruses in cell culture and in animals. 相似文献
993.
肝再生增强因子对外原性抗原引起机体免疫应答影响的研究 总被引:1,自引:0,他引:1
目的 研究rALR对HBsAg及BSA免疫大鼠产生抗体、细胞因子和对脾脏细胞增殖的影响.方法 甲醇诱导表达rALR,测定活性并进行以下研究.①rALR对HBsAg免疫的影响:实验分为:生理盐水、HBsAg20 μg/只、HBsAg20 μg rALR100 μg/kg、HBsAg20 μg rALR 25 μg*kg、HBsAg20 v pPIC9K表达上清、HBsAg20 μg CsA10mg/kg,共6组;②rALR对BSA免疫的影响:实验分为:生理盐水、BSA25 μg/只、BSA25 μg rALR100 μg/kg、BSA25 μg pPIC9K表达上清、BSA25 μg CsA10 mg/kg,共5组.以上均皮下注射免疫大鼠,1次/周×4次,ELISA检测血清中相应抗体、IL-2和IFN-γ.③rALR对大鼠脾细胞增殖的影响:Wisar大鼠先皮下注射HBsAg(20 μg/只)1次,2周后处死,分离脾单核细胞,种板,再加HBsAg 1 μg/孔和/或相应处理因素(rALR、空质粒表达产物等),48h后加3H-TdR,12 h后收集细胞,检测cpm值.结果 rALR100 μg/kg HBsAg组的8只动物中,有2只出现抗HBs的抗体,空质粒对照组和单用HBs Ag组8只动物均出现抗HBs.rALR 100 μg/kg BSA组的8只动物中,有3只出现抗BSA抗体,空质粒对照组和单用BSA组8只动物均出现抗BSA的抗体.rALR 100μg/kg能明显抑制细胞因子IL2及IFN-γ的产生.rALR4μg体外能明显抑制脾细胞的增殖.结论 rALR能抑制HBsAg和BSA诱导大鼠产生相应抗体及IL-2、IFN-γ的产生;体外能抑制经体内致敏的脾细胞的增殖,说明rALR有免疫抑制作用. 相似文献
994.
免疫磁性海藻酸钠载药纳米微球的制备与评价 总被引:6,自引:0,他引:6
靶向治疗系统是目前研究的热点,用微乳化-离子交联方法制备包覆阿霉素的碳包铁/海藻酸钠复合纳米微球,以水溶性碳二亚胺为交联剂,将载药微球与单抗Hab18连接,制备出了免疫磁性药物纳米微球.对该免疫磁性微球的理化性能进行了表征,同时检测了免疫磁性微球中抗体的活性和免疫磁性微球与靶细胞的体外结合情况,结果表明,免疫磁性药物纳米微球平均粒径约为171.2nm,外观为球型,铁含量为14.6%,载药量为10.8%,且具有强磁响应性和长时间药物缓释效果.同时在体外该微球能够与靶细胞特异性结合.这种免疫磁性药物纳米微球有望成为一种优良的靶向肿瘤药物载体. 相似文献
995.
Qin W Gao J Xing Q Yang J Qian X Li X Guo Z Chen H Wang L Huang X Gu N Feng G He L 《Neuroscience letters》2005,375(3):207-210
Recently, proteolipid protein 1 (PLP1) has been identified as downregulated in schizophrenia by quantitative PCR and other technologies. In this work we attempted to investigate the role of PLP1 in the etiology of schizophrenia using a family based association study in 487 Chinese Han family trios. The TDT for allelic association demonstrated that, in male, a weak association was detected in SNP rs475827 with p=0.0294, suggesting that the genetic polymorphisms within PLP1 in male are likely to confer an increased susceptibility to schizophrenia in the Chinese population. 相似文献
996.
Wu HC Lu TY Lee JJ Hwang JK Lin YJ Wang CK Lin CT 《Laboratory investigation; a journal of technical methods and pathology》2004,84(12):1547-1556
To understand whether the p53-regulated mdm2 gene expression was altered by the Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC), the NPC-TW01 cell line was infected by EBV through IgA receptor-mediated endocytosis. The mdm2 gene was expressed only in a small fraction of the NPC cell population and could be enhanced in the EBV-infected (EBV+) cells. In the animals bearing EBV+ and EBV- NPC xenografts, the MDM2+ cells only appeared in clusters in both EBV+ and EBV- tumors with stronger expression in EBV+ cells. Cotransfection of pmdm2-Luc plus pSV40-p53 plus pCMV-LMP1 in the NPC-TW06 line that had p53 heterozygous point mutation showed stronger mdm2 promoter activity than cells cotransfected with pmdm2-Luc plus pSV40-p53, but no mdm2 promoter activity was seen in cells cotransfected with pmdm2-Luc plus pCMV-LMP1. Only the EBV-LMP1 but not the EBV-LMP2A gene could enhance p53 to upregulated mdm2 expression. Tumor cells in NPC biopsy specimens revealed similar mdm2 expression as in the animal model. It is concluded that although EBV can indirectly enhance mdm2 gene expression in tumor cells that express this gene, it cannot turn on or directly regulate mdm2 expression in cells that do not express this gene. In other words, EBV plays a role as an enhancer in NPC tumorigenesis. 相似文献
997.
998.
Lin Ye Jun Nakura Noriaki Mitsuda Asako Takahashi-Fujii Yoshizumi Ishino Ikunoshin Kato Tetsuro Miki Toshio Ogihara 《Journal of human genetics》1996,41(2):257-259
Summary Two polymorphic dinucleotide (CA) repeat dones were isolated from a CEPH mega-YAC clone (844E2), and were localized to chromosome 8 using a panel of 13 mouse/human somatic cell hybrids. 相似文献
999.
1000.