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排序方式: 共有556条查询结果,搜索用时 15 毫秒
91.
Ueric Jos Borges de Souza Raíssa Nunes dos Santos Fabrício Souza Campos Karine Lima Loureno Flavio Guimares da Fonseca Fernando Rosado Spilki Corona-mica.BR/MCTI Network 《Viruses》2021,13(9)
Brazil was considered one of the emerging epicenters of the coronavirus pandemic in 2021, experiencing over 3000 daily deaths caused by the virus at the peak of the second wave. In total, the country had more than 20.8 million confirmed cases of COVID-19, including over 582,764 fatalities. A set of emerging variants arose in the country, some of them posing new challenges for COVID-19 control. The goal of this study was to describe mutational events across samples from Brazilian SARS-CoV-2 sequences publicly obtainable on Global Initiative on Sharing Avian Influenza Data-EpiCoV (GISAID-EpiCoV) platform and to generate indexes of new mutations by each genome. A total of 16,953 SARS-CoV-2 genomes were obtained, which were not proportionally representative of the five Brazilian geographical regions. A comparative sequence analysis was conducted to identify common mutations located at 42 positions of the genome (38 were in coding regions, whereas two were in 5′ and two in 3′ UTR). Moreover, 11 were synonymous variants, 27 were missense variants, and more than 44.4% were located in the spike gene. Across the total of single nucleotide variations (SNVs) identified, 32 were found in genomes obtained from all five Brazilian regions. While a high genomic diversity has been reported in Europe given the large number of sequenced genomes, Africa has demonstrated high potential for new variants. In South America, Brazil, and Chile, rates have been similar to those found in South Africa and India, providing enough “space” for new mutations to arise. Genomic surveillance is the central key to identifying the emerging variants of SARS-CoV-2 in Brazil and has shown that the country is one of the “hotspots” in the generation of new variants. 相似文献
92.
Prenatal ultrasound diagnosis of clubfoot 总被引:1,自引:0,他引:1
Five cases of congenital clubfoot diagnosed prenatally by ultrasound are reported. The incidence of clubfoot may be higher within an affected family and may be associated with other structural anomalies or chromosomal abnormalities. Identifying a clubfoot in utero should therefore alert the sonographer that other anomalies may be present and should lead to a detailed structural survey. 相似文献
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An account is given of how Photodynamic Therapy (PDT) may be used in the diagnosis and treatment of cancer of the head and neck. The role and mode of action of the tumour sensitising agent, Haematoporphyrin derivative (HPD), are shown and the current use of lasers as suitable light sources will be discussed. Individual cases are used to illustrate the current state of this form of treatment and an indication of future developments is provided. 相似文献
96.
Treatment of the port wine stain with the argon laser still remains more of an art form than a scientific technique. Already, some very satisfactory results are being obtained, and these will be improved by greater accuracy in predicting those patients who will respond well to argon laser therapy and by the development of an optimal treatment technique. 相似文献
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U Poddar BR Thapa K Vaiphei KL Rao SK Mitra K Singh 《Archives of disease in childhood》1998,78(3):264-266
The clinical profile, malignant potential, and management of 17 children with juvenile polyposis (more than five juvenile polyps) were evaluated clinically and endoscopically. Colonoscopy and polypectomy were done three weekly until colonic clearance was achieved, and thereafter two yearly. All polyps were subjected to histological examination. Mean age was 7.7 years, with a male preponderance (3:1). Presentation was with rectal bleeding (94%), pallor (65%), stunted growth (53%), and oedema (47%), and the mean (SD) duration of symptoms was 33 (27) months. None had a positive family history or any congenital anomaly. Two children had six polyps up to the transverse colon; the rest had numerous polyps all over the colon. All children had juvenile polyps on histology and 10 (59%) had adenomatous changes (dysplasia). Total colectomy was done in six for intractable symptoms. Colon clearance was achieved in eight after an average 3.4 polypectomy sessions, and three were still on the polypectomy programme. In conclusion, juvenile polyposis is commonly associated with low grade dysplasia. Serial colonoscopic polypectomy is effective but colectomy is required for intractable symptoms and when clearance of the colon is not possible. 相似文献
100.