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排序方式: 共有8162条查询结果,搜索用时 12 毫秒
51.
Vinicius Rossa Luanne Ester Monteiro Ferreira Sancler da Costa Vasconcelos Eric Thomas Tai Shimabukuro Vinicius Gomes da Costa Madriaga Anna Paula Carvalho Sibele Berenice Castell Pergher Fernando de Carvalho da Silva Vitor Francisco Ferreira Carlos Adam Conte Junior Thiago de Melo Lima 《RSC advances》2022,12(22):14084
Nanotechnology experienced a great technological advance after the discovery of the graphene family (graphene – Gr, graphene oxide – GO, and reduced graphene oxide-rGO). Based on the excellent properties of these materials, it is possible to develop novel polymeric nanocomposites for several applications in our daily routine. One of the most prominent applications is for food packaging, offering nanocomposites with improved thermal, mechanical, anti-microbial, and barrier properties against gas and water vapor. This paper reviewed food packaging from its inception to the present day, with the development of more resistant and intelligent packaging. Herein, the most common combinations of polymeric matrices (derived from non-renewable and renewable sources) with Gr, GO, and rGO and their typical preparation methods are presented. Besides, the interactions present in these nanocomposites will be discussed in detail, and their final properties will be thoroughly analyzed as a function of the preparation technique and graphene family-matrix combinations.Food packaging based on nanotechnology of polymeric nanocomposites of graphene and graphene oxide results in packaging with better thermal, mechanical, antimicrobial, electrical packaging, moisture barrier and gas properties. 相似文献
52.
Luísa Martins Miller Flvia Benetti Piccinin Ubele van der Velden Sabrina Carvalho Gomes 《Nutrients》2022,14(9)
Aim: This systematic review examined the additional effect of taking omega-3 supplements on periodontal therapy. Methods: The focused question was “What is the possible effect of omega-3 supplementation concomitant to non-surgical periodontal therapy on clinical periodontal parameters?” Databases Cochrane, Embase, Google Scholar, PubMed, and Web of Science (January-July 2021) were searched to identify appropriate studies. Randomized clinical trials (RCT) about non-surgical therapy with omega-3 supplementation, with at least 3 months of supplementation period were included. Cochrane risk of bias tool version 2 and Grading of Recommendations Assessment, Development, and Evaluation were used. Results: A total of 1556 studies were found, of which eight studies met the inclusion criteria. All eight studies evaluated periodontal probing depth and clinical attachment loss; plaque and gingival inflammation were evaluated in seven studies. High variety of omega-3 dosage, different study lengths, questionable results from periodontal therapy (including test and control groups), high risk of bias and moderate quality of evidence prevented a satisfactory conclusion regarding the benefits of omega-3 supplementation. The studies’ high heterogeneity avoided meta-analysis. Conclusion: Notwithstanding all limitations, the promising effects of omega-3 supplementation presented in two six-month studies encourage performing RCT with better-defined treatment protocols and greater methodological rigor. 相似文献
53.
Carolina Cavaliéri Gomes Vanessa Fátima Bernardes Marina Gonçalves Diniz Luiz De Marco Ricardo Santiago Gomez 《BMC cancer》2012,12(1):61
Background
Development of accurate therapeutic approaches to salivary gland neoplasms depends on better understanding of their molecular pathogenesis. Tumour growth is regulated by the balance between proliferation and apoptosis. Few studies have investigated apoptosis in salivary tumours relying almost exclusively on immunohistochemistry or TUNEL assay. Furthermore, there is no information regarding the mRNA expression profile of apoptotic genes in salivary tumors. Our objective was to investigate the quantitative expression of BCL-2 (anti-apoptotic), BAX and Caspase3 (pro-apoptotic genes) mRNAs in salivary gland neoplasms and examine the association of these data with tumour size, proliferative activity and p53 staining (parameters associated with a poor prognosis of salivary tumours patients). 相似文献54.
Ricardo Faria Walter Santos Vasco Marques Nuno Marques Nélson Tavares Veloso Gomes 《Revista portuguesa de cardiologia》2012,31(6):445-448
Loeffler's endocarditis is an acute form of primary restrictive cardiomyopathy. We report the case of a young woman with pleuritic chest pain associated with fever and hypereosinophilia. She was hospitalized with suspected acute myopericarditis and was treated with aspirin, leading to clinical improvement. Ten days after discharge, she was rehospitalized due to recurrence of chest pain. The echocardiogram showed what appeared to be a mass filling the apex of the right ventricle (RV). She was referred for magnetic resonance imaging, which revealed marked myocardial thickening in the apex of the RV. The patient underwent an endomyocardial biopsy, resulting in a diagnosis of eosinophilic endocarditis. After treatment with prednisolone, all symptoms and the eosinophilia disappeared, and there was complete remission of the RV abnormalities. After three years of follow-up, the patient remains asymptomatic. This case shows that, even without an etiologic diagnosis of eosinophilia, the prognosis for Loeffler's endocarditis can be favorable if treatment is initiated early. 相似文献
55.
César Omar Carranza-Tamayo José Nilton Gomes da Costa Whisllay Maciel Bastos 《The Brazilian journal of infectious diseases》2012,16(6):586-589
Lyme disease is an underdiagnosed zoonosis in Brazil. There are no cases registered in the state of Tocantins, the newest Brazilian state. The cases of three patients in contact with rural areas in three Tocantins’ districts are herein described, and the Brazilian literature is reviewed. 相似文献
56.
57.
Marcos André C. Bezerra Magnun N.N. Santos Aderson S. Araújo Yara M. Gomes Frederico G.C. Abath 《Hemoglobin》2013,37(1):83-88
Various factors have been described as phenotypic modulators of sickle cell disease, such as levels of fetal hemoglobin (Hb F), presence of α-thalassemia (thal), and haplotypes of the β-globin genes. In order to characterize and determine the frequency of the βS and βC mutations and the prevalence of ?α3.7-thal, 74 patients with sickle cell disease detected during neonatal screening in the State of Pernambuco, Brazil, were studied. The haplotypes of the β gene and ?α3.7-thal were determined using polymerase chain reaction (PCR), and specific restriction endonucleases were used to establish the polymorphic sites of the haplotypes. The results showed the high frequency of the Central African Republic (CAR) or Bantu haplotype in the State of Pernambuco, Brazil. The low frequency of the Benin haplotype recorded in this study, in comparison with other states in northeast Brazil, suggests the diversity of origins of Afro-Brazilians in this region. 相似文献
58.
Diagnosis of portal vein thrombosis: value of color Doppler imaging. 总被引:10,自引:0,他引:10
F N Tessler B J Gehring A S Gomes R R Perrella N Ragavendra R W Busuttil E G Grant 《AJR. American journal of roentgenology》1991,157(2):293-296
This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of portal vein thrombosis. Two hundred fifteen patients were studied with color Doppler imaging to determine patency of the main portal vein. Sonographic findings were confirmed in 75 patients, aged 19 to 66 years. Correlation with angiography was obtained in 13 patients, and surgical correlation was obtained in the remaining 62. Nine patients had portal vein thrombosis on the basis of these gold standards. Sonograms were classified as showing either patency or thrombosis, depending on the ability to show color flow within the main portal vein. Agreement between sonography and angiography or surgery was found in 69 patients (61 patent, eight thrombosed). One patient with a patent portal vein at sonography was found to have a thrombosed vessel at surgery, whereas five patients without portal venous flow at sonography had patent vessels at angiography (one patient) or surgery (four patients). Overall sensitivity and specificity for detection of portal vein thrombosis were 89% and 92%, with an accuracy of 92%, a false-negative rate of 0.11, a negative predictive value of 0.98, and a positive predictive value of 0.62. We postulate that the majority of errors in our study occurred in vessels that, although patent, had only sluggish flow, which could not be resolved because of technical limitations. We conclude that color Doppler imaging is a valuable screening procedure for the assessment of portal vein patency. If the sonogram shows a patent portal vein, no further studies are required. However, a lack of demonstrable flow does not always indicate thrombosis, and other imaging studies should be performed for confirmation. 相似文献
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