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排序方式: 共有3811条查询结果,搜索用时 12 毫秒
91.
92.
Fernanda Neves de Carvalho Carolina Toniolo Zenatti Danila Cassia Reis Santana Juliana Maria da Silva Juliane Cristina Oliveira dos As Katia Kisielow dos Anjos Jessica Sigari Cassia de Lima Santos Marcelle Guerra Olivia Pereira Barros Tomaz Cochemore Roberto Camargo Narciso Mario Lucio Baptista Filho 《The Brazilian journal of infectious diseases》2018
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Presumptive Mosaic Partial Trisomy Associated with Congenital Anomalies and Mental Deficiency 下载免费PDF全文
Angela M. Vianna-Morgante Wanderley M. Domingues Claudio C. Ortega Sanae Kasahara 《Journal of medical genetics》1974,11(1):104-108
The case of a mentally retarded patient with congenital anomalies not typical of any known chromosome unbalance is reported. In his karyotype, 40·6% of the cells were normal, while 59·4% had a missing G and an almost metacentric marker longer than an F chromosome. The abnormal cell line was interpreted as resulting from a chromatid translocation involving the short arm of a No. 22 and a segment from an unidentified chromosome. The translocation probably took place after the first cell division and was followed by segregation of the translocated chromatids. Other obvious hypotheses were excluded by the study of fluorescence patterns. The patient's clinical features may be due to a partial autosomal trisomy. 相似文献
96.
Sigurdson CJ Joshi-Barr S Bett C Winson O Manco G Schwarz P Rülicke T Nilsson KP Margalith I Raeber A Peretz D Hornemann S Wüthrich K Aguzzi A 《The Journal of neuroscience》2011,31(39):13840-13847
Transmissible spongiform encephalopathies are fatal neurodegenerative diseases attributed to misfolding of the cellular prion protein, PrP(C), into a β-sheet-rich, aggregated isoform, PrP(Sc). We previously found that expression of mouse PrP with the two amino acid substitutions S170N and N174T, which result in high structural order of the β2-α2 loop in the NMR structure at pH 4.5 and 20°C, caused transmissible de novo prion disease in transgenic mice. Here we report that expression of mouse PrP with the single-residue substitution D167S, which also results in a structurally well ordered β2-α2 loop at 20°C, elicits spontaneous PrP aggregation in vivo. Transgenic mice expressing PrP(D167S) developed a progressive encephalopathy characterized by abundant PrP plaque formation, spongiform change, and gliosis. These results add to the evidence that the β2-α2 loop has an important role in intermolecular interactions, including that it may be a key determinant of prion protein aggregation. 相似文献
97.
Calcium-sensing soluble adenylyl cyclase mediates TNF signal transduction in human neutrophils 下载免费PDF全文
Han H Stessin A Roberts J Hess K Gautam N Kamenetsky M Lou O Hyde E Nathan N Muller WA Buck J Levin LR Nathan C 《The Journal of experimental medicine》2005,202(3):353-361
Through chemical screening, we identified a pyrazolone that reversibly blocked the activation of phagocyte oxidase (phox) in human neutrophils in response to tumor necrosis factor (TNF) or formylated peptide. The pyrazolone spared activation of phox by phorbol ester or bacteria, bacterial killing, TNF-induced granule exocytosis and phox assembly, and endothelial transmigration. We traced the pyrazolone's mechanism of action to inhibition of TNF-induced intracellular Ca2+ elevations, and identified a nontransmembrane ("soluble") adenylyl cyclase (sAC) in neutrophils as a Ca2+-sensing source of cAMP. A sAC inhibitor mimicked the pyrazolone's effect on phox. Both compounds blocked TNF-induced activation of Rap1A, a phox-associated guanosine triphosphatase that is regulated by cAMP. Thus, TNF turns on phox through a Ca2+-triggered, sAC-dependent process that may involve activation of Rap1A. This pathway may offer opportunities to suppress oxidative damage during inflammation without blocking antimicrobial function. 相似文献
98.
Vivian Petersen Wagner Liana Preto Webber Lisley Ortiz Pantelis Varvaki Rados Luise Meurer Osmar Alves Lameira Rafael Rodrigues Lima Manoela Domingues Martins 《Phytotherapy research : PTR》2017,31(8):1283-1288
The effects of topical copaiba oil extract and topical corticosteroid were assessed on oral wound healing in an in vivo model using 96 male Wistar rats. Traumatic ulcers were caused in the dorsum of the tongue using a 3‐mm punch tool. The animals were divided into: Control; Corticosteroid; Placebo and Copaiba oil Group. The animals received two daily applications of the products. The control group received only daily handling. Six rats in each group were euthanized at days 3, 5, 10 and 14. The animals were monitored daily to determine wound status. The weigh was assessed at day 0 and euthanasia day. The percentage of repair was calculated, and histopathological aspects were analyzed. The Kruskal–Wallis test was used to compare the results between groups and times of evaluation. Closing time was assessed through the log‐rank test. The corticosteroid group lost more weight at days 10 and 14 than the control group (p < 0.05). Moreover, the healing time of corticosteroid group was longer than the control group (p = 0.007). No differences were observed between the copaiba oil group and the control group. We concluded that topical copaiba oil, in spite of being safe, did not accelerate the process of oral wound healing. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
99.
Rennan Luiz Oliveira Dos Santos Cintia Baena Elchin Vítor Ancheschi Guiguer-Pinto Dewton de Moraes Vasconcelos Maurício Domingues Ferreira Reinaldo Brito Dias Norberto Nobuo Sugaya Claudete Rodrigues Paula Neide Pena Coto 《Journal de Mycologie Médicale》2022,32(1):101211
Mucormycosis is an aggressive, rare and opportunistic infectious disease, with a high mortality rate. Etiologic agents are filamentous fungi, and infection among humans normally occurs through spore inhalation. A 61-year-old male individual, presenting left eye amaurosis, dark epistaxis, hyperalgesia and malodor underwent clinical examination, which detected ulcerative lesion and wide bone exposure in the hard palate and alveolar ridge. Direct microbiological examination, microbiological culture and lesion biopsy were performed. Non-septate smooth fungal hyphae forming right angles with each other were observed through the direct microbiological examination. Microbiological culture revealed fast-growing fungal colonies with cottony texture, identified as Rhizopus sp. Histopathological examination exhibited necrosis areas, intense mononuclear inflammatory infiltrate and bulky hyphae, thus concluding the mucormycosis diagnosis. Amphotericin B antifungal therapy and surgical intervention were adopted as treatment. The patient was then rehabilitated with maxillofacial prosthesis, subsequently to the healing of the surgical wound. 相似文献
100.
Presence of the cfxA gene in Bacteroides distasonis 总被引:1,自引:0,他引:1
Avelar KE Otsuki K Vicente AC Vieira JM de Paula GR Domingues RM Ferreira MC 《Research in microbiology》2003,154(5):369-374
In this study we investigated the presence of the cfxA gene (encoding a class A beta-lactamase) in 73 strains of the Bacteroides fragilis group belonging to the species B. distasonis (34), B. vulgatus (14), B. thetaiotaomicron (8), B. merdae (6), B. caccae (9) and B. ovatus (2) isolated from human intestinal microflora of healthy children and adults. Employing specific primers to the cfxA gene, a 312-bp amplified fragment was obtained in 2 strains of B. vulgatus and 9 strains, the majority from children, of B. distasonis. The expression of this enzyme was analysed by determining the MICs to cefoxitin and cefotaxime and values varied from 2 to >256 microg/ml of both cefoxitin and cefotaxime. Sequence analysis of the amplicons corresponding to the cfxA gene from B. distasonis and B. vulgatus revealed identical sequences between these isolates and high similarity with other beta-lactamase genes of anaerobes such as cfxA of B. vulgatus (99%) and cfxA2 of Prevotella intermedia (99%), both sequences of which deposited in Genbank under accession numbers U38243 and AF118110, respectively. However, a fragment obtained from a B. distasonis strain (EC17-4) showed a unique RFLP profile and 87% nucleotide similarity with cfxA and cfxA2 genes. These results seem to suggest a dissemination of these resistance determinants among Bacteroides species. 相似文献