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31.
目的:为寻求肠道G杆菌及弧菌快速鉴定的方法。方法:菌种经增菌及分离培养后,取菌落接种于综合生化培养基,并在综合生化培养基管口悬挂硫化氢和靛基质试纸条。同时以克氏双糖铁培养基作对照,置37℃培养18-24h。取综合生化管培养基,外加测试氧化酶,共获取11项生化指标。结果:对689株不同菌种与综合生化管培养基和常规双糖铁培养的测试结果,符合率为99.97%,(7577/7579)和99.79%(7563/7579)。结论:综合生化管是适合医疗卫生单位微生物实验室的一种快速检验方法。  相似文献   
32.
论温病学学科的性质和发展方向   总被引:2,自引:0,他引:2  
温病学核心理论卫气营血和三焦辨证是中医辨证学的重要内容,是临床各科的基础,其理法不仅可以辨治温病,而且可广泛应用于杂病的辨治;温病学学科应界定为基础中医学三级学科。温病学学科的发展方向应在现有研究的基础上,注重温病学理法辨治杂病的研究、温病学名家杂病辨治规律的研究、伤寒学与温病学移植渗透的研究、温病学理论和方法与现代医学理论和方法移植渗透的研究。温病学课程有待分化为:经典温病学、温病学派杂病学、中医传染病学、实验温病学。温病学的概念有待进一步讨论。  相似文献   
33.
Maike Claußen  Beat Suter   《Annals of anatomy》2005,187(5-6):539-553
Many eukaryotic cells depend on proper cell polarization for their development and physiological function. The establishment of these polarities often involve the subcellular localization of a specific subset of proteins, RNAs and organelles. In Drosophila, the microtubule-dependent BicD (BicaudalD) localization machinery is involved in the proper localization of mRNA during oogenesis and embryogenesis and the proper positioning of the oocyte and photoreceptor nuclei. BicD acts together with the minus-end directed motor dynein as well as Egl and Lis-1. The finding that the mammalian homologs of BicD function in retrograde Golgi-to-ER transport has supported the view that BicD may be part of a repeatedly used and evolutionary conserved localization machinery. In this review we focus on the various processes in which BicD is involved during Drosophilian development and in mammals. In addition, we evaluate the interactions between BicD, the dynein localization machinery and associated factors.  相似文献   
34.
We have developed a microarray (DotScan) that enables rapid immunophenotyping and classification of leukaemias and lymphomas by measuring the capture of cells by immobilized dots of 82 CD antibodies [Belov, L., de la Vega, O., dos Remedios, C.G., Mulligan, S.P., 2001. Immunophenotyping of leukemia using a cluster of differentiation antibody microarray. Cancer Res. 61, 4483; Belov, L., Huang, P., Barber, N., Mulligan, S.P., Christopherson, R.I., 2003. Identification of repertoires of surface antigens on leukemias using an antibody microarray. Proteomics 3, 2147]. The DotScan technology has been used to investigate the properties of 498 new antibodies submitted to the HLDA8 Workshop. These antibodies have been applied as 10 nl dots to a film of nitrocellulose on a microscope slide to make an HLDA8 microarray. After blocking the remaining nitrocellulose surface, individual arrays were incubated with each of 7 cell types from a human leukaemia cell panel consisting of three cell lines, CCRF-CEM (a T-cell acute lymphocytic leukaemia), MEC-1 (derived from B-cell chronic lymphocytic leukaemia) and HL-60 (a promyelocytic leukaemia), and four leukaemias from patients: a T-cell prolymphocytic leukaemia, a B-cell chronic lymphocytic leukaemia, and two acute myeloid leukaemias. Leukaemia cells were captured by those immobilized antibodies for which they expressed the corresponding surface molecule. Unbound cells were gently washed off, bound cells were fixed to the arrays and dot patterns were recorded using a DotScan array reader and quantified using DotScan data analysis software. The data obtained show the unique expression profiles of the 7 cell types in the leukaemia cell panel obtained with the DotScan microarray, and the differential capture patterns for these 7 cell types screened against the 498 antibodies in the HLDA8 microarray constructed for this study.  相似文献   
35.
新制备的抗人活化B细胞分化抗原5C5单克隆抗体5C5-G_1经Wester印迹分析表明,该分化抗原经SDS-PAGE(还原条件下)显示五条带,分子量分别为92kD、52kD±(两条)、40kD和20kD。用单抗5C5和单抗5C5-G_1的混合物,从3D5细胞的λgtllcDNA文库中筛选到7个阳性cDNA克隆。  相似文献   
36.
The presence of areas exhibiting a solid/trabecular pattern of growth within an otherwise differentiated thyroid carcinoma represents a source of controversy as regards its proper classification and biologic and prognostic significance. The aim of the current study was to investigate the ultrastructural features of solid/trabecular areas in differentiated thyroid carcinoma and to compare those features with the submicroscopic profile of differentiated, poorly differentiated (insular), and undifferentiated (anaplastic) variants of thyroid cancer. The study series included differentiated carcinoma with solid/trabecular areas (3 cases), conventional papillary carcinoma (4 cases), follicular variant of papillary carcinoma (4 cases), poorly differentiated (insular) carcinoma (3 cases), and undifferentiated (anaplastic) carcinoma (3 cases). It was found that the solid/trabecular areas in differentiated carcinoma and poorly differentiated (insular) carcinoma share similar ultrastructural features and overall retain, even if attenuated, many of the submicroscopic attributes of differentiated carcinomas. In particular, nests of neoplastic cells were observed showing a highly developed cytosecretory apparatus and the presence of numerous abortive/rudimentary follicles, and intercellular and intracellular (intracytoplasmic) lumina/canaliculi of variable morphology. The study supports the hypothesis that the solid/trabecular areas do not merely represent an architectural pattern but rather should be regarded as the expression of a process of reduced differentiation similar to that of poorly differentiated (insular) carcinoma.  相似文献   
37.
人骨髓间质干细胞向造血细胞分化潜能的实验研究   总被引:7,自引:3,他引:7       下载免费PDF全文
目的:在体研究人骨髓间质干细胞(hBMMSCs)向造血细胞分化的潜能。方法:将hBMMSCs经尾静脉注射给环磷酰胺处理的严重联合免疫缺陷(SCID)小鼠,利用流式激活细胞分析系统(FACS)检测hBMMSCs输注后存活35d的SCID小鼠外周血、骨髓和脾脏中人源性造血细胞的表型和水平。结果:hBMMSCs输注组外周血(PB)、骨髓(BM)和脾脏(spleen)中可检测到人CD45+/H-2Dd-、CD34+/H-2Dd-细胞,而对照组PB、BM和脾脏均未检测到上述表型的人造血细胞。结论:hBMMSCs具有向造血细胞分化的潜能。  相似文献   
38.
骨髓间质干细胞体外分化为成骨细胞的实验研究   总被引:13,自引:0,他引:13  
建立猪骨髓间质干细胞 (mesenchymalstemcells ,MSCs)体外分离培养方法。对猪MSCs体外分化为成骨细胞的能力进行研究。抽取猪骨髓 ,体外培养MSCs。取第二代MSCs ,以含有不同浓度的抗坏血酸、β -磷酸甘油、地塞米松及碱性成纤维细胞生长因子等条件培养基进行成骨细胞诱导分化。通过细胞形态变化 ,碱性磷酸酶染色及钙盐沉积对成骨细胞进行鉴定。结果表明MSC细胞形态由长梭形向多边形转变 ,ALP染色阳性 ,VonKossa染色阳性 ,经体外诱导分化后呈典型的成骨细胞样改变。猪骨髓MSCs可在体外长期、稳定培养 ,具有向成骨细胞分化的潜能 ,可以为骨组织工程研究提供较理想的细胞来源和动物模型。  相似文献   
39.
40.
 The formation of the nasal lining with its sensory and its nonsensitive respiratory epithelium requires a spatially ordered pattern of cellular differentiation. Aiming at identifying cell recognition molecules that may be involved in cellular differentiation steps, we applied a panel of antibodies to terminal carbohydrate sequences of the lactoseries on the developing chick olfactory epithelium. This approach is based on the idea that these terminal sugar residues may be involved in certain steps of maturation. Restricted expression of three epitopes NALA, HNK-1, and CD15 was observed in olfactory receptor neurons. The first immature olfactory receptor neurons were observed by day 3 of incubation, expressing the HNK-1 epitope, whereas a total epithelial staining was observed for NALA. By day 9 of incubation high numbers of HNK-1 positive immature olfactory receptor neurons were observed. At the same time mature olfactory receptor neurons showed immunoreactivity for CD15, whereas NALA was still expressed throughout the whole epithelial cell population. However, there was a pronounced staining in the population of mature olfactory receptor neurons. Around hatching only CD15 was detectable in (mature) olfactory receptor neurons, whereas HNK-1 and NALA immunoreactivity have switched to glandular and sustentacular cells respectively. The differentiation-dependent expression patterns of these three cell surface molecules suggest them as suitable markers to explore mechanisms that determine embryonic olfactory receptor neurogenesis. Accepted: 15 October 1997  相似文献   
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