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1.
Environ Sci Pollut Res Int ; 30(36): 84874-84897, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37369899

RESUMEN

Many research articles and reviews have recognized alkali-activated materials (AAMs) as eco-friendly alternative binders to ordinary Portland cement (OPC) due to their economic andenvironmental advantages. However, few literature surveys reported the physical, mechanical and microstructural changes that occur after the exposure of AAMs to elevated temperatures. Owing to the wide diversity in the properties of aluminosilicates, alkali-activation conditions, and additives, a deep survey is needed to understand how different factors can affect the performance of AAMs under elevated temperatures. Therefore, this review extensively discusses the impact of recent critical parameters, including aluminosilicate compositions, aggregate type and mineral, micro, and nano additives, on the behavior of AAMs under thermal load. It can be concluded that regardless of alkali-activator type and concentration, alkali-activated fly ash shows higher thermal resistance than alkali-activated metakaolin and slag. Moreover, the presence of an adequate amount of calcium can increase the thermal stability of AAMs, while the iron has a varying effect on the thermal resistance of AAMs, either positively or negatively. Compared with all additives and aggregates, using waste glass and lightweight aggregates enhanced the thermal resistance of AAMs. Howerver, some types of aggregate having a binding ability which increase the residual strength after heat exposure. Considering the fineness of materials, evaluating the role of nano and micro materials on the properties of AAMs at high temperatures is reviewed. Based on this survey, several promising topics for future work are suggested.


Asunto(s)
Álcalis , Silicatos de Aluminio , Humanos , Calcio , Ceniza del Carbón , Fiebre , Intoxicación por Metales Pesados
2.
Semin Ophthalmol ; 36(7): 531-540, 2021 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-33780299

RESUMEN

Background: von Hippel-Lindau (VHL) syndrome is a multisystem neoplastic disorder involving eyes, central nervous system, kidneys, spine, and other tissues. A retinal capillary hemangioma (RCH) is the earliest manifestation of the VHL disease in most cases.Areas covered:This paper aims to provide an up-to-date review of the current literature about von Hippel-Lindau syndrome. Molecular background, systemic and ocular features of the diseases as well as the utility of newer imaging modalities in diagnosis and monitoring of ocular VHL disease have been described. Besides, we have discussed newer treatment modalities and therapeutic targets.Conclusion: Modern imaging technologies like optical coherence tomography and optical coherence tomography angiography are tools of the trade, in making an appropriate diagnosis and monitoring disease activity and response to treatment. Peripheral RCH may be treated using laser photocoagulation in tumors up to 3000 µm. Vascular endothelial growth factor suppression can help in reducing tumor activity and stabilize the tumor size; however, it does not regress the RCH.


Asunto(s)
Hemangioblastoma , Neoplasias de la Retina , Enfermedad de von Hippel-Lindau , Humanos , Neoplasias de la Retina/diagnóstico , Neoplasias de la Retina/terapia , Tomografía de Coherencia Óptica , Factor A de Crecimiento Endotelial Vascular , Enfermedad de von Hippel-Lindau/complicaciones
3.
5.
Tumori ; 99(1): 100-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23549008

RESUMEN

AIMS: Hepatocellular carcinoma is one of the most aggressive malignant tumors and has limited treatment options. Needle-guided biopsies have been utilized as a tool to diagnose malignant focal hepatic lesions. These techniques are discouraged because of their complications. Nowadays, alpha fetoprotein is the most widely used tumor marker for screening and diagnosis of hepatocellular carcinoma. Nevertheless, this marker has limitations. The diagnostic role of plasma osteopontin as an adjuvant or alternative marker to alpha fetoprotein to detect hepatocellular carcinoma in Egyptian patients with focal hepatic lesions was evaluated in this study. SUBJECT AND METHODS: Eighty participants were recruited from the Egyptian National Liver Institute and were self-assigned to three groups, namely, focal hepatic lesions (n = 40), liver cirrhosis (n = 20), and controls (n = 20). Participants' plasma osteopontin and serum alpha fetoprotein levels were determined and were compared across the three groups. RESULTS: The discriminatory ability of plasma osteopontin for hepatocellular carcinoma was lower than that of alpha fetoprotein. Osteopontin and alpha fetoprotein were not correlated with each other. Neither the gender nor the age of the patients showed a significant association with plasma osteopontin level. CONCLUSION: Measuring plasma osteopontin level alone has no advantage over serum alpha fetoprotein in patients with focal hepatic lesions due to chronic liver disease.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/diagnóstico , Osteopontina/sangre , alfa-Fetoproteínas/metabolismo , Adulto , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Femenino , Humanos , Pruebas de Función Hepática , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Radiografía , Sensibilidad y Especificidad , Turquía
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