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1.
Eur J Surg Oncol ; 47(6): 1473-1480, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33349524

RESUMO

INTRODUCTION: Survival of patients with the same clinical stage varies widely and effective tools to evaluate the prognosis utilizing clinical staging information is lacking. This study aimed to develop a clinical nomogram for predicting survival of patients with Esophageal Squamous Cell Carcinoma (ESCC). MATERIALS AND METHODS: On the basis of data extracted from the SEER database (training cohort, n = 3375), we identified and integrated significant prognostic factors for nomogram development and internal validation. The model was then subjected to external validation with a separate dataset obtained from Jinling Hospital of Nanjing Medical University (validation cohort, n = 1187). The predictive accuracy and discriminative ability of the nomogram were determined by concordance index (C-index), Akaike information criterion (AIC) and calibration curves. And risk group stratification was performed basing on the nomogram scores. RESULTS: On multivariable analysis of the training cohort, seven independent prognostic factors were identified and included into the nomogram. Calibration curves presented good consistency between the nomogram prediction and actual observation for 1-, 3-, and 5-year OS. The AIC value of the nomogram was lower than that of the 8th edition American Joint Committee on Cancer TNM (AJCC) staging system, whereas the C-index of the nomogram was significantly higher than that of the AJCC staging system. The risk groups stratified by CART allowed significant distinction between survival curves within respective clinical TNM categories. CONCLUSIONS: The risk stratification system presented better discriminative ability for survival prediction than current clinical staging system and might help clinicians in decision making.


Assuntos
Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/secundário , Estadiamento de Neoplasias/métodos , Nomogramas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Gradação de Tumores , Reprodutibilidade dos Testes , Medição de Risco/métodos , Programa de SEER , Fatores Sexuais , Taxa de Sobrevida , Carga Tumoral
2.
Chemosphere ; 248: 126082, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32032884

RESUMO

The study investigates transformation mechanism of ions on different waters in Alpine region through analyzed the hydrochemical characteristics of the major ions of precipitation, glacier and snow meltwater, supra-permafrost water and river water in permafrost regions in the Tibetan Plateau under climate warming. The results showed that, The relation between recharge and discharge was the major ways for ionic transformation of each water body. Precipitation and glacier and snow meltwater are the main input sources for ionic transformation, and river water is the final output source. Different water bodies had different ionic concentrations and different hydrochemical types. However, different water bodies in different months (from June to September) also had different hydrochemical types. The water - rock interaction, reactions for ions, dilution effect and other effect for ions played an important role in the process of ion transformation. The increasing of temperature would lead to the accelerated melting of glaciers, permafrost and snow in the alpine regions, so the amount of supra-permafrost water and glacier and snow meltwater will increase, which leads to the increase of runoff. Meanwhile, the increase of temperature makes evaporation stronger. The strong of evaporation will accelerate the transformation of liquid water to gaseous water. Moreover, ion translation and water conversion are synchronous. Accordingly, ions are also accelerating transformation in the process of accelerated transformation of water body. Climate change is not only the main driving force for multiphase water transformation, but also the main driving force for the ion transformation of various water bodies.


Assuntos
Ânions/análise , Cátions/análise , Mudança Climática , Camada de Gelo/química , Rios/química , Neve/química , Altitude , China , Congelamento , Modelos Teóricos , Estações do Ano
3.
Sci Total Environ ; 715: 136911, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32007887

RESUMO

The sources of supra-permafrost water and its hydrological effects were studied, based on the presence of stable isotopes in 562 samples collected in different ablation periods from the source regions of the Yangtze River. The δ18O (δD and d-excess) values for the initial ablation, ablation, and end ablation periods were -10.18‰ (-71.39‰ and 10.08‰), -12.14‰ (-85.58‰ and 11.51‰) and -11.50‰ (-78.75‰ and 13.23‰), respectively. The order of the slopes for the supra-permafrost water evaporation lines from the different ablation periods was initial ablation (IA) > ablation (A) > end ablation (EA). An anti-altitude effect is documented here, for a specific altitude range, in what is believed to be the first record of such an occurrence. Outside of that range, clear altitude effects were apparent. We have been able to show that supra-permafrost water was mainly recharged by atmospheric precipitation, ground ice, and glacier and snow meltwater, in the initial ablation and end ablation periods, and contributions from glacier and snow meltwater were mainly concentrated in higher altitude regions. In contrast, in the ablation period, supra-permafrost water was mainly recharged by atmospheric precipitation and ground ice. The contributions of precipitation to supra-permafrost water were 78.79%, 85.47%, and 82.99% in the initial ablation, ablation, and end ablation periods, respectively. The contributions of ground ice to the supra-permafrost water were 14.05%, 14.53%, and 11.94%, respectively, while contributions of glacier and snow meltwater were 7.15% and 5.07% in the initial and end ablation period. For the initial ablation, ablation, and end ablation periods, contributions from atmospheric precipitation to the supra-permafrost water were 85.47%, 86.86%, and 86.84%, while contributions from ground ice were 14.53%, 13.14% and 13.16%, respectively.

4.
Environ Sci Pollut Res Int ; 26(35): 35767-35778, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701420

RESUMO

The study investigates the hydrochemical type and characteristics of river water in permafrost regions in the Tibetan Plateau by analyzing 532 samples collected from the source region of the Yangtze River. The hydrochemical type of the river water was Cl--Na+-SO42-, and its hydrochemical characteristics were primarily influenced by the soil sources, though the influence of the sea sources and anthropogenic factors could not be ignored. Significant negative correlations were found between temperature and NO3-, SO42-, Mg2+, Ca2+, and between precipitation, relative humidity, and SO42- and Mg2+ in the river water. River water in the higher altitudes of over 5000 m above sea level was mainly recharged from glacier snowmelt water and by the supra-permafrost water and precipitation at the altitudes between 3500 and 5000 m above sea level. The controlled sources of hydrochemical characteristics of glacier snowmelt water were different for different ablation rates in the area with elevations of over 5000 m above sea level. Different hydrochemical types in different ablation rates implied the hydrochemical type was extremely sensitive to ablation periods in areas with elevation of over 5000 m above sea level. However, hydrochemical type was not sensitive to ablation periods from 3500 to 5000 m above sea level. The ionic concentration of glacier snowmelt water was mainly controlled by pollutants in glaciers and snow. Melting rates of glacier snowmelt water also had a certain effect on ionic concentration. Meanwhile, the stability of the hydrochemical type implied river water mainly controlled the hydrochemical type from 3500 to 5000 m above sea level. Hydrochemical type had no effect on elevation in end ablation.


Assuntos
Água Doce/química , Íons/química , Solo/química , Poluentes Químicos da Água/análise , Altitude , Camada de Gelo , Rios , Neve , Temperatura , Água
5.
Molecules ; 24(17)2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31454945

RESUMO

Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) is rich in functional compounds such as rutin, quercetin, d-chiro-inositol, dietary fiber, and essential amino acids. Electric field (EF) treatment before sprout germination results in physiological and chemical changes, and some alterations might lead to positive applications in plant seeds. MTT assay showed that the effect of total flavonoids on human gastric cancer cell line MGC80-3 was significantly changed after EF treatment for different germination days (3-7 days). Among them, the total flavonoids of tartary buckwheat (BWTF) on the third day had the most obvious inhibitory effect on MGC80-3 (p < 0.01). In addition, flow cytometry evidenced that different ratios of quercetin and rutin had effects on the proliferation of MGC80-3. The same content of quercetin and rutin had the best effect, reaching 6.18 ± 0.82%. The anti-cancer mechanism was mainly promoted by promoting the expression of apoptotic proteins. The expression of Bax/Bcl-2 and caspase-8 in MGC80-3 cells was mediated by BWTFs. This study has good research value for improving the biological and economic value of tartary buckwheat.


Assuntos
Fagopyrum/fisiologia , Quercetina/farmacologia , Rutina/farmacologia , Neoplasias Gástricas/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Fagopyrum/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Germinação , Humanos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Quercetina/isolamento & purificação , Rutina/isolamento & purificação , Neoplasias Gástricas/tratamento farmacológico , Proteína X Associada a bcl-2/metabolismo
6.
Nanomaterials (Basel) ; 8(10)2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30274166

RESUMO

An auxiliary electrode introduced in traditional spinneret electrospinning is an effective and powerful technique to improve the production rate of nanofibers. In this work, the effects of the arrangement of auxiliary electrode, applied voltage, injection speed, and the distance between the electrode tip and the spinneret tip (ESD) on the jet number and the morphology of polyvinyl alcohol (PVA) nanofibers were investigated systematically. The results showed that the number of jets firstly increased and then decreased with the increase of applied voltage and ESD, respectively, while increasing with the injection speed in both the auxiliary electrode in the vertical position and parallel position. The average nanofiber diameter decreased with increasing of applied voltage and injection speed, but decreasing in ESD in these two positions. The numerical simulation results revealed that the auxiliary electrode primarily influenced the electric field intensity in the spinning area. This work provides a deep understanding of multiple jets in electrospinning.

7.
Nat Prod Bioprospect ; 4(5): 309-13, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25294221

RESUMO

Various kinds of biologically active peptides have previously been isolated from the skin secretions of Amolops loloensis frog, such as antimicrobial peptides, bradykinin-like peptides and algesic peptides. A novel insulinotropic peptide named amolopin was identified in A. loloensis frog's skin secretion. Its primary structure sequence was determined by Edman degradation as: FLPIVGKSLSGLSGKL-NH2. BLAST search indicates that the amino acid sequence of amolopin is quite different from other known insulin secretagogues, including mastoparan, exendins and α-latrotoxin, nor does it like incretins (e.g. glucagons like peptide-1 and glucose-dependent insulinotropic ploypeptide) either. However, amolopin shows certain structural similarity with amphibian antimicrobial temporins and vespid chemotactic peptides isolated from Vespa magnifica. Amolopin can stimulate insulin release in INS-1 cells in a dose-dependent manner. Primary investigation on its action mechanisms reveals that amolopin does not increase the influx of Ca(2+). In conclusion, a novel 16-amino acid peptide with insulin-releasing activity is initially discovered from the skin secretion of A. loloensis frog. Further work is necessary to evaluate its potential as novel anti-diabetic candidate.

8.
Huan Jing Ke Xue ; 35(12): 4465-74, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25826914

RESUMO

A total of 90 precipitation samples were collected from individual precipitation events at the Qilian Alpine Ecology & Hydrology Research Station (Hulugou Station, 30 degrees 47'N, 90 degrees 58'E; 3 260 m a. s. l) located in the central Qilian Mountains from August 2012 to November 2013. All samples were analyzed for major cations (Na, K+, Ca2+ and Mg2+), anions (Cl- , NO3- and SO4(2-)) and conductivity. Precipitation EC values ranged from 2.26 to 482 µS x cm(-1) with an average value of 41.9 µS x cm(-1). The precipitation was of SO4(2-) -Mg(2+) -Ca2+ type, which contributed > 70% to the total ionic concentration. The same as the precipitation alkalinity, precipitation events occurred around summer showed lower concentrations, while it had higher concentrations in winter and spring with little precipitation and larger wind speed. Enrichment factor (EF), correlation and factor analysis indicated that regional crustal aerosols and species from central Asian and northwestern China arid regions brought by the westerly circulation were the major sources for these ions, some dust from human pollution were the secondary sources, and the contribution of sea salt was the least due to the long distance transport. These characteristics could be also confirmed by the correlation between ionic concentrations and metrological data in the study region. It is also interesting that the precipitation chemistry was different under the different atmospheric circulation: the monsoon precipitation, the interaction precipitation events ( influenced both by monsoon and westerly) and the westerly precipitation.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Aerossóis , Ânions , Cátions , China , Clima , Poeira , Íons , Estações do Ano , Vento
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