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211.
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M Kemali E Sada A Miralto G Zummo 《Zeitschrift für mikroskopisch-anatomische Forschung》1983,97(1):3-14
The central myelin of the phylogenetically ancient shark Scyllium stellare (Elasmobranchii, Selachii) was examined at the electron microscope. The known different chemical compositions of the myelin in higher and lower vertebrates is not associated in the Scyllium with a lack of any basic structural myelin elements, but is probably linked to variations in the myelin compactness and periodicity. Several unusual myelin structures and irregular patterns of unknown origin have been observed. The relationship between myelin-forming cells and the most external layers of myelinated structures suggest the possibility that the cytoplasmic glial wrapping is not the only mechanism responsible for central myelination in this vertebrate. 相似文献
213.
Albert Eduardo Silva Martins Norma Lucena-Silva Renan Gomes Garcia Stefan Welkovic Aureliana Barboza Maria Luiza Bezerra Menezes Magda Maruza Terezinha Tenório Ricardo AA Ximenes 《Memórias do Instituto Oswaldo Cruz》2014,109(6):738-747
Human immunodeficiency virus (HIV)-positive patients have a greater prevalence of
coinfection with human papillomavirus (HPV) is of high oncogenic risk. Indeed, the
presence of the virus favours intraepithelial squamous cell lesion progression and
may induce cancer. The aim of this study was to evaluate the prevalence of HPV
infection, distribution of HPV types and risk factors among HIV-positive patients.
Cervical samples from 450 HIV-positive patients were analysed with regard to oncotic
cytology, colposcopy and HPV presence and type by means of polymerase chain reaction
and sequencing. The results were analysed by comparing demographic data and data
relating to HPV and HIV infection. The prevalence of HPV was 47.5%. Among the
HPV-positive samples, 59% included viral types of high oncogenic risk. Multivariate
analysis showed an association between HPV infection and the presence of cytological
alterations (p = 0.003), age greater than or equal to 35 years (p = 0.002), number of
partners greater than three (p = 0.002), CD4+ lymphocyte count <
200/mm3 (p = 0.041) and alcohol abuse (p = 0.004). Although high-risk
HPV was present in the majority of the lesions studied, the low frequency of HPV 16
(3.3%), low occurrence of cervical lesions and preserved immunological state in most
of the HIV-positive patients were factors that may explain the low occurrence of
precancerous cervical lesions in this population. 相似文献
214.
In order to elucidate the full serological characteristics of strain Ictero No. I, the first strain of Leptospira isolated by Inada and Ido in 1914, 17 monoclonal antibodies against the strain were produced by cell fusion technology. The antibody-producing hybridomas were designated IMAs 1 to 17. The reactivities of the monoclonal antibodies produced by the hybridomas were determined by the microscopic agglutination test. One of the 17 monoclonal antibodies, IMA 1, reacted with strains Ictero No. I, LT 1131 and Naam, but not with other strains of the serogroup Icterohaemorrhagiae including strain RGA used in the present study. Moreover, the reactivity of the antigenic determinant of IMA 1 was inactivated by treatment at 56 C for 30 min. The 16 other monoclonal antibodies, IMAs 2 to 17, showed different reaction patterns against Leptospira strains of the serogroup Icterohaemorrhagiae. All of the 16 antibodies reacted with both Ictero No. I and RGA strains. The antigens against antibodies IMAs 2 to 17 were thermostable. The present study thus clarified the presence of a thermolabile antigen in strain Ictero No. I, and allowed correct distinction between the serotype of strain Ictero No. I and that of strain RGA using IMA 1. Therefore, we propose that strain Ictero No. I represents serovar icterohaemorrhagiae, as originally designated by Inada and Ido. Moreover, strain Ictero No. I should be designated as the type strain of Leptospira interrogans. 相似文献
215.
Archives of Microbiology - 相似文献
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Eighteen serovars (19 strains) of serogroup Icterohaemorrhagiae were serologically analyzed using 18 monoclonal antibodies against serovar copenhageni Shiromizu, M20 and serovar icterohaemorrhagiae RGA strains. The reaction patterns of the serovars against these monoclonal antibodies were different. According to these results, we divided the serovars, except for serovar tonkini, into the following three subgroups: Subgroup 1 reacted to many monoclonal antibodies including serovars icterohaemorrhagiae, copenhageni, hualien, monymusk, mankarso, and budapest. Subgroup 2 fell between subgroups 1 and 3 including serovars dakota, naam, bogvere, birkini, smithi, ndambari, gem, ndahambukuje and mwogolo. Subgroup 3 reacted to only a few monoclonal antibodies: serovars weaveri and sarmin. Serovar tonkini did not react to any of the monoclonal antibodies used. There is a possibility that serovar tonkini does not belong to serogroup Icterohaemorrhagiae. Further studies on the serological reactions of each strain revealed that it was impossible to distinguish the RGA strain from the serovar hualien LT11-31 strain, indicating that they may be identical. It was also observed that serovar copenhageni and monymusk seemed to be closely related. Serovars birkini and smithi, and serovars ndambari and gem were alike in their serological reactivities. Among the 18 monoclonal antibodies, RGAMA-1 was a unique antibody which reacted only to serovar icterohaemorrhagiae and serovar hualien, indicating that it must be the serovar icterohaemorrhagiae specific antibody. On the other hand, SHIRMA-2, 5, 6 reacted to all the serovars except for serovars weaveri, sarmin, and tonkini. These antibodies exhibited a broad reaction spectrum. 相似文献
220.