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1.
J Environ Manage ; 278(Pt 2): 111559, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33137686

RESUMO

Given rapid environmental change, the development of new, data-driven, interdisciplinary approaches is essential for improving assessment and management of river systems, especially with respect to flooding. In the world's extensive drylands, difficulties in obtaining field observations of major hydrological events mean that remote sensing techniques are commonly used to map river floods and assess flood impacts. Such techniques, however, are dependent on available cloud-free imagery during or immediately after peak discharge, and single images may omit important flood-related hydrogeomorphological events. Here, we combine multiple Landsat images from Google Earth Engine (GEE) with precipitation datasets and high-resolution (<0.65 m) satellite imagery to visualise flooding and assess the associated channel-floodplain dynamics along a 25 km reach of the unvegetated, ephemeral Río Colorado, Bolivia. After cloud and shadow removal, Landsat surface reflectance data were used to calculate the Modified Normalized Difference Water Index (MNDWI) and map flood extents and patterns. From 2004 through 2016, annual flooding area along the narrow (<30 m), shallow (<1.7 m), fine-grained (dominantly silt/clay) channels was positively correlated (R2 = 0.83) with 2-day maximum precipitation totals. Rapid meander bend migration, bank erosion, and frequent overbank flooding was associated with formation of crevasse channels, splays, and headward-eroding channels, and with avulsion (shifting of flow from one channel to another). These processes demonstrate ongoing, widespread channel-floodplain dynamics despite low stream powers and cohesive sediments. Application of our study approaches to other dryland rivers will help generate comparative data on the controls, rates, patterns and timescales of channel-floodplain dynamics under scenarios of climate change and direct human impacts, with potential implications for improved river management.


Assuntos
Inundações , Rios , Agricultura , Colorado , Humanos , Hidrologia
2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 42(6): 657-661, 2017 Jun 28.
Artigo em Chinês | MEDLINE | ID: mdl-28690223

RESUMO

OBJECTIVE: To determine drug dose and usage of timolol maleate eye drops in the treatment of superficial infantile hemangioma.
 Methods: A total of 250 superficial hemangioma infants were recruited and assigned into 5 groups (n=50 for each group): an external application group and 4 exterior coating groups (2, 4, 6, 8 times per day). We evaluated the therapeutic effect of different methods for drug application (external application or exterior coating) and the frequency for drug administration on superficial infantile hemangioma.
 Results: The external application group (twice a day and 0.5 hour per time) showed better effect than that in the exterior coating group with twice a day (P<0.001). The difference in therapeutic effect between the exterior coating group with 6 times a day and exterior coating group with twice a day or with 3 times a day was significant (P<0.001). The differences in drug efficacy were not found among the exterior coating group with 6 times a day, the exterior coating group with 8 times a day, or the external application group with twice a day (All P>0.05).
 Conclusion: Drug dose may affect the therapeutic effect of timolol maleate eye drops in superficial hemangioma infants, and exterior coating with 6 times a day may achieve the best curative effect.


Assuntos
Neoplasias Oculares/tratamento farmacológico , Hemangioma/tratamento farmacológico , Soluções Oftálmicas/administração & dosagem , Timolol/administração & dosagem , Administração Tópica , Esquema de Medicação , Humanos , Lactente , Resultado do Tratamento
3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 40(8): 907-11, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26333501

RESUMO

OBJECTIVE: To explore the safe method with anhydrous ethanol injection in the treatment of venous malformation.
 METHODS: A total of 96 patients with venous malformation were conducted anhydrous ethanol injection for 245 times through percutaneous puncture by three-point method. The complications were observed. In animal experiment, according to the different concentrations of anhydrous ethanol injection, rats were divided into an anhydrous ethanol group, a 75% ethanol group, a 50% ethanol group and a 25% ethanol group (n=5 in each group), and the damage of vessels after ethanol injection was observed.
 RESULTS: The successful rate for three-point ethanol injection was 88%. The incidence for both skin ulcer and numbness was 0.9% without severe complications in lung and heart. In the animal experiments, the entire vessel wall including outer membrane was damaged in the anhydrous ethanol group. Part of vessel walls, including the inner membrane and muscle layer, were damaged in both the 75% ethanol group and the 50% ethanol group. However, there was no damage in the vessels in the 25% ethanol group.
 CONCLUSION: With the decrease in ethanol concentration, the vascular damage is decreased and eventually disappeared. Three-point anhydrous ethanol injection is safe and effective.


Assuntos
Etanol/uso terapêutico , Soluções Esclerosantes/uso terapêutico , Escleroterapia , Malformações Vasculares/terapia , Animais , Etanol/administração & dosagem , Humanos , Injeções/métodos , Ratos
4.
Mol Med Rep ; 10(4): 1845-50, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25119498

RESUMO

MacroH2A is the most frequently altered histone, which participates in cancer progression. Increasing evidence demonstrates that cancer progression could be regulated by macroH2A by affecting the cell cycle. In the present study, it was demonstrated that macroH2A suppresses melanoma cell progression and the molecular mechanisms underlying this process were examined. The interference and overexpression vectors of macroH2A were constructed and then transferred into B16 melanoma cells and, following transfection, were analyzed by quantitative polymerase chain reaction (PCR), western blot analysis and immunofluorescence assays. Apoptosis and the cell cycle stage among all the treatment groups were detected. Then, cyclin D1, cyclin D3, cyclin-dependent protein kinase (CDK) 4, CDK6 and CDK8 expression was detected in order to elucidate the effects of macroH2A on cell cycle-related genes. The results demonstrated that the overexpression of macroH2A suppressed melanoma cell progression and arrested the cells in the G2/M stage. Furthermore, macroH2A inhibits cyclin D1, cyclin D2, CDK6 and CDK8 expression in B16 melanoma cells. In conclusion, the results demonstrated that macroH2A, a critical component of chromatin, suppresses the development of melanoma (which results from a disordered cell cycle) through regulating cyclin D1, cyclin D3 and CDK6 genes.


Assuntos
Histonas/metabolismo , Animais , Linhagem Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclina D3/genética , Ciclina D3/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Quinase 8 Dependente de Ciclina/genética , Quinase 8 Dependente de Ciclina/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular , Histonas/antagonistas & inibidores , Histonas/genética , Pontos de Checagem da Fase M do Ciclo Celular , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo
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