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91.
We have examined the patterns of expression of the major intermediate filament (IF) protein mRNAs during development of the hamster brain. Quantitative northern blotting was used to examine changes in the levels of mRNAs for the low, middle and high molecular weight neurofilament proteins (NF-L, NF-M, NF-H) as well as peripherin, vimentin and glial fibrillary acidic protein (GFAP). Total RNA was isolated from hamster brains at embryonic (E) days 12 and 14 and postnatal (P) days 1, 3, 5, 7, 9, 11, 13, 15, 20, 28 and 60-90 (adult), and probed with specific IF cDNAs. Northern blotting revealed that NF-L and NF-M mRNAs were present at very low levels in embryonic brain and that significant expression of these genes only occurred postnatally when the levels increased dramatically until P28 and then declined again in the adult. Increases in NF-H mRNA levels were somewhat delayed relative to those of NF-L and NF-M. NF-H mRNA was not seen at embryonic stages and was expressed at very low levels prior to P9; after that time the levels increased rapidly until P28 and then declined in the adult. Two of the type III IF genes, peripherin and vimentin, followed a pattern of expression opposite that of the NF genes. Both peripherin and vimentin mRNAs were present in embryonic brain and were expressed at higher levels during early postnatal stages than at later times. The magnitude and rate of reduction in vimentin gene expression in the postnatal interval was much greater than that of peripherin. GFAP mRNA levels were extremely low prior to P9 after which a robust increase occurred, followed by a decline in the adult. We discuss the implication of the dramatic changes in IF isotype expression in brain to the pathways of both neuronal and glial development in vivo. 相似文献
92.
Tang Jian汤健 Wang Yu王瑜 Zkang Chenhui张晨晖 E. Costa Institute of Cardiovascular Research Beijing Medical University 《北京大学学报(医学版)》1994,(Z1)
THECLONINGOFNa ̄+/Ca ̄(2+)EXCHANGERGENEANDITSEXPRESSIONINBRAINISCHEMIATangJian汤健,WangYu王瑜,ZkangChenhui张晨晖,E.CostaInstituteofCar... 相似文献
93.
Efficient RT-PCR on platelet mRNA after long-term storage 总被引:1,自引:0,他引:1
We have developed a procedure permitting RT-PCR from mRNA even after a long-term storage (1 year) of platelet samples in ethanol (EtOH-platelets) at −80°C. To validate our method, we have analysed the human platelet alloantigen system (HPA-1) which is coded by β3 mRNA. We have also demonstrated the efficiency of amplification of part of the coding region for (i) αIIb subunit mRNA, (ii) αv subunit mRNA, and (iii) the seven transmembrane domain thrombin receptor mRNA. 相似文献
94.
Characterization of proliferative responses and cytokine mRNA profiles induced by Vespula venom in patients with severe reactions to wasp stings 总被引:2,自引:0,他引:2
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M BONAY H ECHCHAKIR D LECOSSIER P LAIN D HERMAN A J HANCE P SOLER A TAZI 《Clinical and experimental immunology》1997,109(2):342-356
95.
Les rétinopathies vasculaires peuvent être accompagnées d'une modification de la forme des vaisseaux. Les patients atteints courent le risque de perdre la vue. Jusqu'ici, les méthodes utilisées par les ophthalmologistes pour analyser ces modifications sont qualitatives. Nous proposons une méthode nouvelle d'analyse de la tortuosité des vaisseaux de la rétine en vue d'élaborer par la suite un outil d'aide au diagnostic des rétinopathies vasculaires. La première étape de la méthode est une représentation symbolique de la structure vasculaire de la rétine. La deuxième étape appelée reconstitution 2D est la classification des entités vasculaires en gros vaisseaux (artères ou veines) et en petits vaisseaux (artérioles ou veinules) en utilisant la moyenne du diamèetre et du niveau de gris des segments de vaisseau comme paramètres discriminants. La dernière étape consiste à calculer l'excentricité des vaisseaux pour décrire leur tortuosité. Pour s'assurer de la capacité de l'excentricitéà décrire les petites modifications de forme, un second paramètre a été défini à titre comparatif. Les résultats obtenus permettent de quantifier les modifications de forme des vaisseaux. 相似文献
96.
The binding of human complement components C3, C5 and C9 to the surface of the infective larvae of the nematode parasites Toxocara canis and Trichinella spiralis, by the alternative pathway, was examined by direct and indirect immunofluorescence on the intact parasites. This showed that although C3 bound to both nematodes, they differed markedly in the binding of C5 and C9; C5 bound only minimally to T. spiralis, and C9 binding to this parasite was barely detectable. In contrast, both early and late components bound to T. canis to a high density, comparable to, or in excess of, the binding of these components to the infective larvae of the trematode Schistosoma mansoni. The lack of binding of the post-C3 components to T. spiralis did not correlate with enhanced binding of the control protein, Factor H. 相似文献
97.
J. Byström R. C. Garcia† L. Håkansson M. Karawajczyk L. Moberg J. Soukka‡ P. Venge 《Clinical and experimental allergy》2002,32(7):1082-1091
BACKGROUND: Eosinophil cationic protein (ECP) is an eosinophil-derived protein, which has been shown to be present in circulating neutrophils. OBJECTIVE: To establish whether ECP is produced or internalized by peripheral blood neutrophils. METHODS: This was done using microscopy, flow cytometry, fractionation of cells and RT-PCR techniques. RESULTS: No ECP mRNA was detected after extensive cell purification to eliminate all traces of contaminating eosinophils. Examination of immunostained neutrophils by light, confocal, electron microscopy together with cell fraction experiments, established that ECP is present intracellularly and is mostly associated to cell granules. Uptake studies by flow cytometry and by using both cold and radiolabelled ECP showed that it is internalized by neutrophils and stored in some proportion in their primary granules. Upon stimulation with serum-treated Sephadex particles, the internalized ECP was partially released from cells. CONCLUSION: ECP is not produced but can be internalized by circulating neutrophils, which take it from the environment and partially store it in their primary granules. 相似文献
98.
目的 评价血清肿瘤标志物甲胎蛋白(AFP)、癌胚抗原(CEA)、糖类抗原50(CA50)、糖类抗原19—9(CA19—9)、铁蛋白(SF)、神经元特异性烯醇化酶(NSE)、细胞角蛋白19片段(CYFlRA21—1)水平对肺癌诊断的临床价值。方法 测定72例肺癌患者和40例良性肺病患者的血清AFP、CEA、CA50、CA19—9、SF、NSE、CYFRA21—1水平,比较两组的差异。结果 肺癌组患者CEA、CA50、CA19—9、SF、NSE、CY—FRA21—1水平高于良性肺病组,AFP对肺癌的诊断价值不大。NSE CYF、RA21—1的联合检测具有良好的阳性和阴性预测值。六项联合检测的敏感性和准确性最高,但与两项联合检测的敏感性和准确性差异无统计学意义。结论 NSE CYFRA21—1的联合检测具有良好的临床应用前景。 相似文献
99.
100.
H. Kaneda T. K. Waddell M. de Perrot X.-H. Bai C. Gutierrez T. Arenovich C. Chaparro M. Liu S. Keshavjee 《American journal of transplantation》2006,6(3):544-551
While current donor selection with clinical findings is generally effective, the imprecise nature of the assessment forces clinicians to remain on the conservative side. A reliable biological marker would assist donor selection and would improve donor organ utilization. We collected biopsies from 169 donor lungs before implantation. Expression levels of IL-6, IL-8, IL-10, TNF-alpha, IFN-gamma and IL-1beta were measured by quantitative real-time RT-PCR (qRT-PCR). Seventeen cases died within 30 days after transplantation. No donor factor was significantly associated with 30-day mortality. Univariate analysis of the 84 cases for development of the prediction model showed that IL-6, IL-8, TNF-alpha and IL-1beta were risk factors for mortality and IL-10 and IFN-gamma were protective factors. We analyzed the cytokine expression ratios of risk to protective cytokines. A stepwise logistic regression for 30-day mortality demonstrated that a model containing the ratio of IL-6/IL-10 was the most predictive (p = 0.0013). When applied to the remaining 85 cases for validation, the test of model fit was significant (p = 0.039). Using the cytokine ratio, we were able to define three risk groups with striking differences in survival (p = 0.0003). Multi-cytokine analysis of the donor lung graft with qRT-PCR shows significant promise as a strategy to biologically evaluate the donor lung prior to implantation. 相似文献