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1.
Hepatobiliary Surg Nutr ; 12(2): 264-266, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37124691
2.
Front Endocrinol (Lausanne) ; 14: 1123642, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37113484

RESUMEN

Purpose: The purpose of this study was to examine trends in the incidence and incidence-based (IB) mortality of functional pancreatic neuroendocrine tumors(F-PNETs), and to identify factors associated with survival times. Methods: Data were obtained from the Surveillance, Epidemiology, and End Results database from 2000 to 2017. Trends in the age-adjusted incidence of F-PNETs and IB mortality were examined using the Joinpoint Regression Program. Statistical analyses were run using chi-square tests, Kaplan-Meier curves, and the Cox proportional hazards model. Multiple imputation was used to deal with missing data. Results: A total of 142 patients with F-PNETs met the study inclusion criteria. It was found that the incidence of F-PNETs decreased over the study period, with an annual percent change (APC) of -2. 5% (95% CI [-4. 3, -0. 5], P<0. 05). This decrease was found to be significant for women, and also when limited to cases with distant disease or rare F-PNETs, with APCs of -4. 2% (95% CI [-7. 4, -0. 9], P<0. 05), -6. 7% (95% CI [-10. 4, -2. 8], P<0. 05), and -9. 1% (95% CI [-13. 5, -4. 4], P<0. 05), respectively. The Cox regression analysis revealed that the tumor size, tumor stage, tumor type, and surgical resection were associated with F-PNETs mortality. Conclusions: This was the first population-based epidemiological study of F-PNETs and we found a continual decrease in the incidence of F-PNETs from 2000 to 2017. The prognosis and survival times were closely related to the calendar year at diagnosis, tumor stage, and tumor size.


Asunto(s)
Adenoma de Células de los Islotes Pancreáticos , Tumores Neuroectodérmicos Primitivos , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Femenino , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/patología , Tasa de Supervivencia , Pronóstico
3.
Sci Total Environ ; 879: 163102, 2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-36966835

RESUMEN

Wheat-rice cropping system in China, characterized by smallholder with conventional practice, is energy- and carbon-intensive. Cooperative with scientific practice is a promising practice to increase resource use while reducing environmental impact. However, comprehensive studies of the energy and carbon (C) budgeting of management practices on the actual field-scale production under different production types are lacking. The present research examined the energy and C budgeting of smallholder and cooperative using conventional practice (CP) or scientific practice (SP) at the field scale level in the Yangtze River Plain, China. The SPs and cooperatives exhibited 9.14 % and 6.85 % and 4.68 % and 2.49 % higher grain yields over the corresponding CPs and smallholders, respectively, while maintaining 48.44 % and 28.50 % and 38.81 % and 20.16 % higher net income. Compared to the CPs, the corresponding SPs reduced the total energy input by 10.35 % and 7.88 %, and the energy savings were primarily attributable to reductions in fertilizer, water, and seeds through the use of improved techniques. The total energy input in the cooperatives was 11.53 % and 9.09 % lower than that for the corresponding smallholders due to the mechanistic enhancements and improved operational efficiency. As a result of the increased yields and reduced energy inputs, the SPs and cooperatives ultimately increased energy use efficiency. The high productivity attributed to increased C output in the SPs, which increased C use efficiency and the C sustainability index (CSI) but decreased the C footprint (CF) over the corresponding CPs. The higher productivity and more efficient machinery of cooperatives increased the CSI and reduced the CF compared to the corresponding smallholders. Overall, the SPs coupled with cooperatives were the most energy efficient, C efficient, profitable and productive for wheat-rice cropping systems. In the future, improved fertilization management practices and integration of smallholder farms were effective means for developing sustainable agriculture and promoting environmental safety.

4.
J Clin Med ; 12(2)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36675604

RESUMEN

Background: This study aimed to determine the role of surgical treatment in patients with stage II intrahepatic cholangiocarcinoma (iCCA). Methods: Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. We divided stage II iCCAs into solitary tumors with vascular invasion (T2sN0M0) and multiple tumors with/without vascular invasion (T2mN0M0) according to the criteria of AJCC v.8. The Kaplan−Meier method and log-rank test were used to evaluate differences in overall survival (OS). We performed two propensity score-matching analyses with (PSM2) or without (PSM1) surgical treatment. Results: 667 and 778 iCCA patients with stage II and IIIB were recruited. After PSM2, there was no survival difference in stage II iCCA patients in hypothetical conditions with similar surgical proportions (p = 0.079). However, OS was significantly worse in patients with T2mN0M0 than T2sN0M0 when the actual surgical proportion existed after PSM1 (p < 0.001). OS was similar between T2mN0M0 and IIIB regardless of whether PSM1 (p = 0.907) or PSM2 (p = 0.699) was performed. The surgical treatment was verified to associate with prognosis. Conclusions: The survival benefit by surgical treatment was existed in Stage II but not in Stage IIIB iCCA patients. The OS for T2mN0M0 will approach that of T2sN0M0 if the surgical proportion is gradually increased.

5.
Sci Rep ; 10(1): 11318, 2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32647368

RESUMEN

Labile organic carbon (LOC) fractions and related enzyme activities in soils are considered to be early and sensitive indicators of soil quality changes. We investigated the influences of fertilization and residue incorporation on LOC fractions, enzyme activities, and the carbon pool management index (CPMI) in a 10-year field experiment. The experiment was composed of three treatments: (1) no fertilization (control), (2) chemical fertilizer application alone (F), and (3) chemical fertilizer application combined with incorporation of wheat straw residues (F + R). Generally, the F + R treatment led to the highest concentrations of the LOC fractions. Compared to the control treatment, the F + R treatment markedly enhanced potential activities of cellulase (CL), ß-glucosidase (BG), lignin peroxidase (LiP), and manganese peroxidase (MnP), but decreased laccase (LA) potential activity. Partial least squares regression analysis suggested that BG and MnP activities had a positive impact on the light-fraction organic carbon (LFOC), permanganate-oxidizable carbon (POXC), and dissolved organic carbon (DOC) fractions, whereas laccase activity had a negative correlation with those fractions. In addition, the F + R treatment significantly increased the CPMI compared to the F and control treatments. These results indicated that combining fertilization with crop residues stimulates production of LOC and could be a useful approach for maintaining sustainable production capacity in lime concretion black soils along the Huai River region of China.

6.
Sci Total Environ ; 725: 138358, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32464746

RESUMEN

Minimization of cadmium (Cd) accumulation in wheat is an effective method to prevent Cd-related health risks to humans. To understand the underlying mechanisms of restricting Cd transport, the role of nodes in Cd restriction was studied in eight Chinese wheat cultivars. The Cd accumulation differed significantly among the cultivars. The grain Cd concentrations were mainly dependent on the Cd concentrations in the roots and shoots. The Cd transport in the shoots controlled the wheat grain Cd accumulations. Nodes in the wheat stem have distinct functions in the transfer, distribution, and restriction of Cd. The node connected to the panicle showed the lowest translocation factors. The area of the vascular bundles, especially the diffuse vascular bundles, in the junctional node with the flag leaf was the key factor in restricting Cd transfer to the wheat grain. There was a significant relation between these areas and the grain Cd concentrations. The conclusion of this study is that screening or breeding cultivars with low Cd concentrations in the roots or with smaller areas of diffuse vascular bundles in the junctional nodes with the flag leaf is an effective strategy to decrease Cd concentration in wheat grains.


Asunto(s)
Cadmio/análisis , Contaminantes del Suelo/análisis , Grano Comestible/química , Humanos , Hojas de la Planta/química , Raíces de Plantas/química , Triticum
7.
J Agric Food Chem ; 68(9): 2607-2614, 2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32096642

RESUMEN

Fused-ring aromatics, important skeletal components of black carbon (BC), contribute to long-term carbon (C) sequestration in nature. They have previously been thought to be primarily formed by incomplete combustion of organic materials, whereas the nonpyrogenic origins are negligible. Using advanced solid-state 13C nuclear magnetic resonance (NMR), including recoupled long-range C-H dipolar dephasing, exchange with protonated and nonprotonated spectral editing (EXPANSE), and dipolar-dephased double-quantum/single-quantum (DQ/SQ) spectroscopy, we for the first time identify fused-ring aromatics that formed during the decomposition of wheat (Triticum sp.) straw in soil under aerobic, but not anaerobic conditions. The observed formation of polyaromatic units as plant litter decomposes provides direct evidence for humification. Moreover, the estimation of the annual flux of such nonpyrogenic BC could be equivalent to 3-12% of pyrogenic BC added to soils from all other sources. Our findings significantly extend the understanding of potential sources of fused-ring aromatic C and BC in soils as well as the global C cycle.


Asunto(s)
Triticum/química , Aerobiosis , Bacterias/metabolismo , Biodegradación Ambiental , Tallos de la Planta/química , Tallos de la Planta/microbiología , Microbiología del Suelo , Triticum/microbiología
8.
Carbon Balance Manag ; 14(1): 20, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31889246

RESUMEN

BACKGROUND: A significant source of greenhouse gas (GHG) emissions comes from the manufacture of synthetic nitrogen (N) fertilizers consumed in crop production processes. And the application of synthetic N fertilizers is recognized as the most important factor contributing to direct N2O emissions from agricultural soils. Based on statistical data and relevant literature, the GHG emissions associated with synthetic N manufacture and fertilization for wheat and maize in different provinces and agricultural regions of China were quantitatively evaluated in the present study. RESULTS: During the 2015-2017 period, the average application rates of synthetic N for wheat and maize in upland fields of China were 222 and 197 kg ha-1, respectively. The total consumption of synthetic N on wheat and maize was 12.63 Mt year-1. At the national scale, the GHG emissions associated with the manufacture of synthetic N fertilizers were estimated to be 41.44 and 59.71 Mt CO2-eq year-1 for wheat and maize in China, respectively. And the direct N2O emissions derived from synthetic N fertilization were estimated to be 35.82 and 69.44 Gg N2O year-1 for wheat and maize, respectively. In the main wheat-cultivating regions of China, area-scaled GHG emissions were higher for Inner Mongolia, Jiangsu and Xinjiang provinces. And for maize, Gansu, Xinjiang, Yunnan, Shannxi and Jiangsu provinces had higher area-scaled GHG emissions. Higher yield-scaled GHG emissions for wheat and maize mainly occured in Yunnan and Gansu provinces. CONCLUSIONS: The manufacture and application of synthetic N fertilizers for wheat and maize in Chinese croplands is an important source of agricultural GHG emissions. The current study could provide a scientific basis for establishing an inventory of upland GHG emissions in China and developing appropriate mitigation strategies.

9.
Environ Pollut ; 244: 218-227, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30340168

RESUMEN

There is an increasing evidence linking protective effect of selenium (Se) against Pb toxicology; however, Pb exposure risk assessments usually consider only the environmental Pb contamination and dietary intake. Based on the current understanding of mechanisms of SePb interactions, the physiological function/toxicology of Se and the toxicology of Pb, a new criterion for Se and Pb exposure assessment is developed. Additionally, seven existing criteria were also used to assess the resident health risks around a smelter in China. The Pb concentrations in locally-produced foods exceeded the national tolerance limits of China and the Se in the foods were similar to those in areas with adequate Se levels. In accordance with the illustrated assessments of the new criterion and seven existing criteria, we found a large knowledge gap between the new and traditional assessments of exposure to Pb and/or Se. The new assessment criteria suggested that almost all the residents were facing the Se deficiency and 58% of the residents not only had the adverse health of Se deficiency, but also had the health risks of Pb toxicity. The Pb and Se in the hair and urine may partly support the new criterion. This study suggested that the process of Se counteracting the Pb toxicity may result in Se deficiency. Pb exposure combined Se intake should be considered in future assessments of Pb exposure (or Se intake).


Asunto(s)
Exposición a Riesgos Ambientales/normas , Plomo/toxicidad , Medición de Riesgo/normas , Selenio/deficiencia , Selenio/uso terapéutico , China , Humanos
10.
Ecotoxicol Environ Saf ; 147: 708-714, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28938141

RESUMEN

Combinations of remediation technologies are needed to solve the problem of soil contamination in paddy rice, due to multiple potential toxic elements (PTEs). Two potential mitigation methods, water management and in-situ remediation by soil amendment, have been widely used in treatment of PTE-polluted paddy soil. However, the interactive relationship between soil amendment and water management, and its influence on the accumulation of PTEs in rice are poorly understood. Greenhouse pot experiments were conducted to examine the effects of phosphate amendment on Cd and Pb availability in soil and their influence on Cd and Pb uptake into rice, on Fe and P availability in soil, and on the alteration of Fe amount and compartment on root surface among different water management strategies. Results indicated that Cd and Pb content in the shoot and grain were significantly affected by the different water management strategies in nonamended soils, and followed the order: wetting irrigation > conventional irrigation > continuous flooding. The application of phosphate amendment significantly decreased the variations of Cd and Pb absorption in shoot and grain of rice among different water treatments. The reasons may be attributed to the enhancement of P availability and the decrease of Fe availability in soil, and the decreased variations of Fe2+/Fe3+ content in root coating after the application of phosphate amendment. These results suggested that the simultaneous use of phosphate amendment and continuous flooding to immobilize Cd and Pb, especially in acid paddy soils, should be avoided.


Asunto(s)
Riego Agrícola/métodos , Cadmio/análisis , Restauración y Remediación Ambiental/métodos , Plomo/análisis , Oryza/química , Contaminantes del Suelo/análisis , Suelo/química , Ácidos , China , Grano Comestible/química , Contaminación Ambiental/prevención & control , Concentración de Iones de Hidrógeno , Modelos Teóricos , Oryza/crecimiento & desarrollo , Raíces de Plantas/química
11.
PLoS One ; 12(6): e0178110, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28604783

RESUMEN

Changes in physicochemical characteristics, chemical structures and maturity of swine, cattle and chicken manures and composts during 70-day composting without addition of bulking agents were investigated. Physicochemical characteristics were measured by routine analyses and chemical structures by solid-state 13C NMR and FT-IR. Three manures were of distinct properties. Their changes in physicochemical characteristics, chemical structures, and maturity were different not only from each other but also from those with addition of bulking agents during composting. Aromaticity in chicken manure composts decreased at first, and then increased whereas that in cattle and swine manure composts increased. Enhanced ammonia volatilization occurred without addition of bulking agents. NMR structural information indicated that cattle and chicken composts were relatively stable at day 36 and 56, respectively, but swine manure composts were not mature up to day 70. Finally, the days required for three manures to reach the threshold values of different maturity indices were different.


Asunto(s)
Estiércol/análisis , Animales , Bovinos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Nitrógeno , Espectroscopía Infrarroja por Transformada de Fourier , Porcinos , Temperatura
12.
Environ Sci Pollut Res Int ; 24(13): 12328-12337, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28357796

RESUMEN

Low methane production and high levels of heavy metal in pig slurries limit the feasibility of anaerobic digestion of pig manure. In this study, changes in the methane production and bioavailability of heavy metals in the anaerobic digestion of diluted pig manure were evaluated using single and combined action of microscale zero-valence iron (ZVI) and magnetite. After 30 days of anaerobic digestion, the methane yield ranged from 246.9 to 334.5 mL/g VS added, which increased by 20-26% in the group added with microscale ZVI and/or magnetite relative to that in the control group. Results of the first-order kinetic model revealed that addition of microscale ZVI and/or magnetite increased the biogas production potential, rather than the biogas production rate constant. These treatments also changed the distribution of chemical fractions for heavy metal. The addition of ZVI decreased the bioavailability of Cu and Zn in the solid digested residues. Moreover, a better performance was observed in the combined action of microscale ZVI and magnetite, and the ZVI anaerobic corrosion end-product, magnetite, might help enhance methane production through direct interspecies electron transfer in ZVI-anaerobic digestion process.


Asunto(s)
Hierro , Estiércol , Anaerobiosis , Animales , Disponibilidad Biológica , Óxido Ferrosoférrico , Metales Pesados , Metano , Porcinos
13.
PLoS One ; 11(7): e0158172, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27380023

RESUMEN

Soil aeration is a crucial factor that regulates crop residue decomposition, and the chemical composition of decomposing crop residues may change the forms and availability of soil nutrients, such as N and P. However, to date, differences in the chemical composition of crop straw residues after incorporation into soil and during its decomposition under anaerobic vs. aerobic conditions have not been well documented. The objective of the present study was to assess changes in the C-containing functional groups of wheat straw residue during its decomposition in anaerobic and aerobic environments. A 12-month incubation experiment was carried out to investigate the temporal variations of mass, carbon, and nitrogen loss, as well as changes in the chemical composition of wheat (Triticum aestivum L) straw residues under anaerobic and aerobic conditions by measuring C-containing functional groups using solid state nuclear magnetic resonance (NMR) spectroscopy. The residual mass, carbon content, and nitrogen content of the straw residue sharply declined during the initial 3 months, and then slowly decreased during the last incubation period from 3 to 12 months. The decomposition rate constant (k) for mass loss under aerobic conditions (0.022 d-1) was higher than that under anaerobic conditions (0.014 d-1). The residual mass percentage of cellulose and hemicellulose in the wheat straw gradually declined, whereas that of lignin gradually increased during the entire 12-month incubation period. The NMR spectra of C-containing functional groups in the decomposing straw under both aerobic and anaerobic conditions were similar at the beginning of the incubation as well as at 1 month, 6 months, and 12 months. The main alterations in C-containing functional groups during the decomposition of wheat straw were a decrease in the relative abundances of O-alkyl C and an increase in the relative abundances of alkyl C, aromatic C and COO/N-C = O functional groups. The NMR signals of alkyl C and aromatic C in decomposing wheat straw residues under anaerobic condition were higher than those under aerobic conditions. The higher mass percentages of lignin and the higher signals of aromatic C and alkyl C functional groups in decomposing wheat residues under anaerobic conditions than under aerobic conditions were due to the slower decomposition rates of aryl C and alkyl C in wheat straw residues under anaerobic conditions.


Asunto(s)
Ciclo del Carbono , Tallos de la Planta/química , Suelo/química , Triticum/química , Aerobiosis , Anaerobiosis , Carbono/análisis , Carbono/metabolismo , Celulosa/análisis , Celulosa/metabolismo , Cinética , Lignina/análisis , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Nitrógeno/análisis , Nitrógeno/metabolismo , Oxígeno/metabolismo , Tallos de la Planta/metabolismo , Polisacáridos/análisis , Polisacáridos/metabolismo , Factores de Tiempo , Triticum/metabolismo
14.
Environ Pollut ; 147(2): 387-93, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-16996667

RESUMEN

The effects of two sulfur (S) sources (SO(4)(2-), S(0)), and three rates of S application (0, 30, 120 mgS/kg) on the formation of iron plaque in the rhizosphere, and on the root surface of rice, and As (arsenic) uptake into rice (Oryza sativa L.) were studied in a combined soil-sand culture experiment. Significant differences in As uptake into rice between +S and -S treatments were observed in relation to S sources, and rates of S application. Concentrations of As in rice shoots decreased with increasing rates of S application. The mechanism could be ascribed to sulfur, induced the formation of iron plaque, since concentrations of Fe in iron plaque on quartz sands in the rhizosphere, and on the root surface of rice increased with increasing rates of S application. The results suggest that sulfur fertilization may be important for the development approaches to reducing As accumulation in rice.


Asunto(s)
Arsénico/análisis , Hierro/metabolismo , Oryza/metabolismo , Contaminantes del Suelo/análisis , Azufre/metabolismo , Arseniatos/análisis , Ambiente Controlado , Concentración de Iones de Hidrógeno , Hierro/análisis , Manganeso/análisis , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Cuarzo/química , Plantones/metabolismo , Sulfatos/análisis , Azufre/análisis
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