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排序方式: 共有4515条查询结果,搜索用时 15 毫秒
1.
Zaida Araujo Sietze Brandes Elena Pinelli María A. Bochichio Andrea Palacios Albina Wide Bruno Rivas-Santiago Juan Carlos Jiménez 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(1):47-55
The present study aimed at measuring seropositivities for infection by
Ascaris suum and Toxocara canis using the
excretory/secretory (E/S) antigens from Ascaris suum (AES) and
Toxocara canis (TES) within an indigenous population. In
addition, quantification of cytokine expressions in peripheral blood cells was
determined. A total of 50 Warao indigenous were included; of which 43 were adults and
seven children. In adults, 44.1% were seropositive for both parasites; whereas
children had only seropositivity to one or the other helminth. For ascariosis, the
percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%,
respectively. While that for toxocariosis, the percentage of TES seropositivity in
adults and children was low; 9.3% and 14.3%, respectively. The percentage of
seronegativity was comparable for AES and TES antigens in adults (27.9%) and children
(28.6%). When positive sera were analyzed by Western blotting technique using AES
antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the
TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9,
98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that
Blastocystis hominis, Hymenolepis nana and
Entamoeba coli were the most commonly observed intestinal
parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and
IL-4 expressions showed that there was only a significant increased expression of
IL-4 in indigenous with TES seropositivity (p < 0.002).
Ascaris and Toxocara seropositivity was
prevalent among Warao indigenous. 相似文献
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Adilson Cunha Ferreira Edward Araujo Júnior Wellington P. Martins João Francisco Jordão Antônio Hélio Oliani Simon E. Meagher 《The journal of maternal-fetal & neonatal medicine》2015,28(14):1706-1710
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality. 相似文献
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C M Kyaw C R De Araujo M R Lima E G S Gondim M M Brígido L G Giugliano 《Infection, genetics and evolution》2003,3(2):111-117
Diffusely adhering Escherichia coli (E. coli) strains (DAEC) represent a potential cause of diarrhoea in infants, and the detection of type three secretion system (TTSS) genes in DAEC would substantiate their pathogenic nature. In this work, four isolates of DAEC, recovered from stools of diarrhoeic children, were analysed by PCR, in order to detect the presence of TTSS genes. Primers targeted to the escC, escJ, escN and escV, some of the most conserved TTSS genes in enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC), were used in order to verify the occurrence of homologous genes in our DAEC isolates. By this approach, we were able to characterise DNA fragments corresponding to putative escJ and escN genes in all DAEC isolates. Furthermore, DNA fragments homologous to the escC and escV genes were also amplified from all isolates. Besides the similarity found among the DAEC esc homologues with EPEC and EHEC esc genes, the nucleotide sequence analysis of the flanking regions of the amplified DNA fragments suggests that the putative DAEC esc genes are organised in the same manner as observed in EPEC and in EHEC strains. The results described here provide strong evidence for the presence of a TTSS in the DAEC strains analysed, implicating a pathogenic nature of these isolates. 相似文献
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