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排序方式: 共有339条查询结果,搜索用时 15 毫秒
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Mariana Carvalho de Menezes Vanderlei Pascoal de Matos Maria de Ftima de Pina Bruna Vieira de Lima Costa Larissa Loures Mendes Milene Cristine Pessoa Paulo Roberto Borges de Souza-Junior Amlia Augusta de Lima Friche Waleska Teixeira Caiaffa Letícia de Oliveira Cardoso 《Journal of urban health》2021,98(2):285
To overcome the challenge of obtaining accurate data on community food retail, we developed an innovative tool to automatically capture food retail data from Google Earth (GE). The proposed method is relevant to non-commercial use or scholarly purposes. We aimed to test the validity of web sources data for the assessment of community food retail environment by comparison to ground-truth observations (gold standard). A secondary aim was to test whether validity differs by type of food outlet and socioeconomic status (SES). The study area included a sample of 300 census tracts stratified by SES in two of the largest cities in Brazil, Rio de Janeiro and Belo Horizonte. The GE web service was used to develop a tool for automatic acquisition of food retail data through the generation of a regular grid of points. To test its validity, this data was compared with the ground-truth data. Compared to the 856 outlets identified in 285 census tracts by the ground-truth method, the GE interface identified 731 outlets. In both cities, the GE interface scored moderate to excellent compared to the ground-truth data across all of the validity measures: sensitivity, specificity, positive predictive value, negative predictive value and accuracy (ranging from 66.3 to 100%). The validity did not differ by SES strata. Supermarkets, convenience stores and restaurants yielded better results than other store types. To our knowledge, this research is the first to investigate using GE as a tool to capture community food retail data. Our results suggest that the GE interface could be used to measure the community food environment. Validity was satisfactory for different SES areas and types of outlets. 相似文献
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Hosman HJ Viersen PT de Koomen HA van Drie HJ Folmer T Grevers A 《Nederlands tijdschrift voor tandheelkunde》1993,100(4):214-216
The Br?nemark system for implant supported bridges has been carried out in Amsterdam since 1982. One hundred patients with a maxillary conventional full denture and a mandibular fixed tissue-integrated prosthesis were selected for this study. Before and long after the treatment, questionnaires were sent to these patients in order to gain information of their experiences. The treatment had greatly benefitted the patients, in spite of the problem of the loose lower denture in some cases was shifted to the upper jaw. 相似文献
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Pedro H.M. Moraes Marcelo Straus Takahashi Felipe A.B. Vanderlei Marcelo V. Schelini Danielle A. Chacon Marcos Roberto Tavares Maria Cristina Chammas 《Ultrasound in medicine & biology》2021,47(5):1219-1226
The purpose of this study was to select thyroid nodules most at risk for malignancy among those cytologically undetermined by fine-needle aspiration biopsy (FNAB), using B-mode, color duplex Doppler and 2-D shear wave shear wave elastography (2-D-SWE). This was a prospective diagnostic accuracy study with 62 Bethesda III/IV nodules according to FNAB (atypia/follicular lesion of undetermined significance or follicular neoplasia/Hürthle cell neoplasm). Ultrasonography (US) data were compared with resection histologic results, revealing 35 of 62 benign nodules (56.4%) and 27 of 62 carcinomas (43.6%). Conventional US was uses to evaluate nodule echogenicity, dimensions, contours, presence of halo and microcalcifications. Doppler US was used to assess the vascularization (exclusively or predominantly peripheral or central) and mean resistance index of three nodule arteries. Elastography was used to evaluate the nodule elastographic pattern; mean nodule deformation index; deformation ratio between nodule and adjacent thyroid parenchyma; and mean deformation ratio between nodule and pre-thyroid musculature (MDR). Statistical analysis included χ2, Fisher's exact, Student's t, Mann–Whitney tests and multivariable analysis by multiple logistic regression. Areas under the receiver operating characteristic curves (AUC-ROCs) were used for accuracy analysis. Fifty-eight participants (54.7 ± 14.0 y, 51 women) were studied. The parameters that were statistically significant to the univariate analysis were hypo-echogenicity, nodule diameter greater than width and all parameters analyzed from Doppler and elastography. Multivariate analysis revealed that the MDR (in kPa) was the best parameter for risk analysis of indeterminate nodules. Nodules with MDRs >1.53 exhibited a greater chance of malignancy (AUC-ROC = 0.98). We conclude that 2-D-SWE is able to select malignant nodules among those cytologically indeterminate, thus avoiding unnecessary surgery in these cytologic groups. 相似文献
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Ismael Nilo Lino de Queiroz Ana Luíza Gomes Quinderé José Ariévilo Gurgel Rodrigues Edfranck de Sousa Oliveira Vanderlei Natássia Albuquerque Ribeiro Renata Line da Conceição Rivanor Kátia Alves Ribeiro Chistiane Oliveira Coura Karuza Maria Alves Pereira Hellíada Vasconcelos Chaves Mirna Marques Bezerra Ianna Wivianne Fernandes de Araújo Norma Maria Barros Benevides 《Inflammation research》2015,64(12):971-982
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Renato Graciano de Paula Alice Maria de Magalhães Ornelas Enyara Rezende Morais William de Castro Borges Massimo Natale Lizandra Guidi Magalhães Vanderlei Rodrigues 《Parasitology research》2014,113(8):2887-2897
The trematode Schistosoma mansoni, an important parasite of humans, is the principle agent of the disease schistosomiasis. In the human host, one of the most important stress factors of this parasite is the oxidative stress generated by both the metabolism of the worm and the immune system of the host. The proteasomal system is responsible for protein homeostasis during oxidative stress. The 26S proteasome is a multicatalytic protease formed by two compartments, a 20S core and regulatory particle 19S, and controls the degradation of intracellular proteins, hence regulating many cellular processes. In the present report, we describe the biochemical characterization and role of the 20S proteasome in the response of adult S. mansoni worms exposed to hydrogen peroxide. Characterization of the response to the oxidative stress included the evaluation of viability, egg production, mortality, tegument integrity, and both expression and activity of proteasome. We observed decreases in viability, egg production as well as 100 % mortality at the higher concentrations of hydrogen peroxide tested. The main changes observed in the tegument of adult worms were peeling as well as the appearance of bubbles and a decrease of spines on the tubercles. Furthermore, there were increases in 26S activity to the same extent as 20S proteasome activity, although there was increase of 20S proteasome content, suggesting that degradation of protein oxidized in adult worms is due to the 20S proteasome. It was demonstrated that adult S. mansoni worms are sensitive to oxidative stress, and that a variety of processes in this parasite are altered under this condition. The work contributes to a better understanding of the mechanisms employed by S. mansoni to survive under oxidative stress. 相似文献