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1.
Sci Rep ; 10(1): 2714, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066760

RESUMO

Rubber dams are widely used for landscaping in urban rivers and they retain large amounts of sediments. The sediments are rich in phosphorus (P) which can cause river eutrophication. Little is known about P release in rubber dams. We investigated the potential of sediment P release by isotherm experiment in an urban river with 30 rubber dams of northern China. We found that the potential of sediment P release (percentage saturation of zero equilibrium P concentration, EPCsat) was 76% at natural river part above dams, and then decreased to 67% at the 4th dam because of high deposition of fine sediments within the upper 4 dams. Between the 5th and the 30th dams, EPCsat increased to 90% because of the decrease of fine sediments and water soluble reactive P. EPCsat was also significantly higher (p < 0.05) in April and August than in November. The results suggest that the potential of sediment P release in this dammed river was mainly controlled by sediment grain size and biological effects. Therefore, management strategies for dammed rivers should focus on reducing P inputs and improving the hydraulic conditions.

2.
BMC Surg ; 19(1): 98, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31340806

RESUMO

BACKGROUND: In this systematic review and meta-analysis, we aimed to determine the risk factors associated with neck hematoma requiring surgical re-intervention after thyroidectomy. METHODS: We systematically searched all articles available in the literature published in PubMed and CNKI databases through May 30, 2017. The quality of these articles was assessed using the Newcastle-Ottawa Quality Assessment Scale, and data were extracted for classification and analysis by focusing on articles related with neck hematoma requiring surgical re-intervention after thyroidectomy. Our meta-analysis was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. RESULTS: Of the 1028 screened articles, 26 met the inclusion criteria and were finally analyzed. The factors associated with a high risk of neck hematoma requiring surgical re-intervention after thyroidectomy included male gender (odds ratio [OR]: 1.86, 95% confidence interval [CI]: 1.60-2.17, P < 0.00001), age (MD: 4.92, 95% CI: 4.28-5.56, P < 0.00001), Graves disease (OR: 1.81, 95% CI: 1.60-2.05, P < 0.00001), hypertension (OR: 2.27, 95% CI: 1.43-3.60, P = 0.0005), antithrombotic drug use (OR: 1.92, 95% CI: 1.51-2.44, P < 0.00001), thyroid procedure in low-volume hospitals (OR: 1.32, 95% CI: 1.12-1.57, P = 0.001), prior thyroid surgery (OR: 1.93, 95% CI: 1.11-3.37, P = 0.02), bilateral thyroidectomy (OR: 1.19, 95% CI: 1.09-1.30, P < 0.0001), and neck dissection (OR: 1.55, 95% CI: 1.23-1.94, P = 0.0002). Smoking status (OR: 1.19, 95% CI: 0.99-1.42, P = 0.06), malignant tumors (OR: 1.00, 95% CI: 0.83-1.20, P = 0.97), and drainage used (OR: 2.02, 95% CI: 0.69-5.89, P = 0.20) were not significantly associated with postoperative neck hematoma. CONCLUSION: We identified certain risk factors for neck hematoma requiring surgical re-intervention after thyroidectomy, including male gender, age, Graves disease, hypertension, antithrombotic agent use, history of thyroid procedures in low-volume hospitals, previous thyroid surgery, bilateral thyroidectomy, and neck dissection. Appropriate intervention measures based on these risk factors may reduce the incidence of postoperative hematoma and yield greater benefits for the patients.


Assuntos
Doença de Graves/cirurgia , Hematoma/cirurgia , Tireoidectomia/efeitos adversos , Drenagem , Doença de Graves/complicações , Hematoma/etiologia , Humanos , Pescoço/cirurgia , Reoperação , Fatores de Risco
3.
Environ Sci Pollut Res Int ; 25(21): 21070-21085, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29767311

RESUMO

Uncertainty analysis is an important prerequisite for model application. However, the existing phosphorus (P) loss indexes or indicators were rarely evaluated. This study applied generalized likelihood uncertainty estimation (GLUE) method to assess the uncertainty of parameters and modeling outputs of a non-point source (NPS) P indicator constructed in R language. And the influences of subjective choices of likelihood formulation and acceptability threshold of GLUE on model outputs were also detected. The results indicated the following. (1) Parameters RegR2, RegSDR2, PlossDPfer, PlossDPman, DPDR, and DPR were highly sensitive to overall TP simulation and their value ranges could be reduced by GLUE. (2) Nash efficiency likelihood (L1) seemed to present better ability in accentuating high likelihood value simulations than the exponential function (L2) did. (3) The combined likelihood integrating the criteria of multiple outputs acted better than single likelihood in model uncertainty assessment in terms of reducing the uncertainty band widths and assuring the fitting goodness of whole model outputs. (4) A value of 0.55 appeared to be a modest choice of threshold value to balance the interests between high modeling efficiency and high bracketing efficiency. Results of this study could provide (1) an option to conduct NPS modeling under one single computer platform, (2) important references to the parameter setting for NPS model development in similar regions, (3) useful suggestions for the application of GLUE method in studies with different emphases according to research interests, and (4) important insights into the watershed P management in similar regions.


Assuntos
Modelos Teóricos , Fósforo/análise , Poluição da Água/análise , China , Funções Verossimilhança , Incerteza
4.
Breast ; 34: 115-121, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28577471

RESUMO

PURPOSE: To evaluate the clinicopathological features, patterns of distant metastases, and survival outcome between stage IV male breast cancer (MBC) and female breast cancer (FBC). METHODS: Patients diagnosed with stage IV MBC and FBC between 2010 and 2013 were included using the Surveillance, Epidemiology, and End Results program. Univariate and multivariate Cox regression analyses were used to analyze risk factors for overall survival (OS). RESULTS: A total of 4997 patients were identified, including 60 MBC and 4937 FBC. Compared with FBC, patients with MBC were associated with a significantly higher rate of estrogen receptor-positive, progesterone receptor-positive, unmarried, lung metastases, and a lower frequency of liver metastases. Univariate and multivariate analyses showed no significant difference in OS between MBC and FBC. In the propensity score-matched population, there was also no difference in survival between MBC and FBC. Multivariate analysis of MBC showed that OS was longer for patients aged 50-69 years and with estrogen receptor-positive disease. CONCLUSIONS: There was no significant difference in survival outcome between stage IV MBC and FBC, but significant differences in clinicopathological features and patterns of metastases between the genders.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias da Mama Masculina/mortalidade , Neoplasias da Mama/mortalidade , Carcinoma/mortalidade , Neoplasias Hepáticas/mortalidade , Neoplasias Pulmonares/mortalidade , Fatores Etários , Idoso , Neoplasias Encefálicas/secundário , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama Masculina/metabolismo , Neoplasias da Mama Masculina/patologia , Carcinoma/metabolismo , Carcinoma/secundário , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pontuação de Propensão , Modelos de Riscos Proporcionais , Receptores Estrogênicos , Receptores de Progesterona , Programa de SEER , Fatores Sexuais , Taxa de Sobrevida , Estados Unidos/epidemiologia
5.
Ying Yong Sheng Tai Xue Bao ; 26(6): 1831-9, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26572039

RESUMO

Social economy in Huaihe River Basin had undergone enormous changes during 1990-2010. The grain yield had increased by 58%, from 64.14 million tons to 101.21 million tons, and the urbanization rate had increased by 22%, from 13% to 35%. Assessing the negative impacts of these high intensive human activities caused by rapid social development on terrestrial ecosystem would serve as a scientific basis for quantitative management of regional ecology. This paper estimated the spatial and temporal distribution of net anthropogenic nitrogen input (NANI) in Huaihe River Basin during 1990-2010. The results showed that there was an increasing trend in NANI in the period of 1990-2001, and after that this trend was slower. The NANI increased from approximately 17232 kg N · km(-2) · a(-1) in 1990 to a peak of 28771 kg N · km(-2) · a(-1) in 2003, and then declined to 26415 kg N · km(-2) · a(-1) in 2010. Chemical fertilizer and atmospheric deposition were the largest two sources of NANI, followed by food & feed import and biological nitrogen. Contributions from both chemical fertilizer and atmospheric deposition had been increasing continuously, respectively from 64% and 16% in 1990 to 77% and 19%. Our findings implied that the shift from fertilizer-supported agriculture and fossil fuel-supported industry to sci-tech lead economic development is urgently needed.


Assuntos
Agricultura , Monitoramento Ambiental , Fertilizantes , Nitrogênio/análise , China , Ecossistema , Atividades Humanas , Humanos , Rios , Urbanização
6.
Oncol Lett ; 9(2): 595-603, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25621028

RESUMO

Gastric cancer is the fourth most common type of malignant tumor, with a poor prognosis. Focal adhesion kinase (FAK) mediates the crosslink of intracellular signaling networks, playing a key role in cell migration and invasion. The aim of the present study was to investigate the effects of FAK interference on the proliferation ability, invasion and metastasis of gastric cancer cells. The FAK-RNAi lentiviral vector was infected into SGC7901 gastric cancer cells in order to observe the in vivo situations of tumor growth and metastasis before and after the FAK interference. The growth of SGC7901 gastric cancer cells in the interference group was significantly inhibited compared with that of the negative control (P<0.05) and the blank control groups (P<0.05), and the FAK expression significantly decreased (P<0.05). The in vitro invasion and metastasis experiments showed that the cell invasion and metastasis abilities of the interference group significantly decreased when compared with those of the negative control (P<0.05) and blank control groups (P<0.05). In the nude mouse subcutaneous tumor transplantation model, the mean ± standard deviation tumor weight of the interference group (1.474±0.9840 g) was lower than that of the negative control (3.134±0.3299 g) and blank control (2.68±0.12 g) groups (P<0.05). In the nude mice, the liver and peritoneal metastasis rates of the interference group were significantly lower than those of the negative control (P<0.05) and the blank control groups (P<0.05), and the FAK mRNA of the interference group significantly reduced (P<0.05). In conclusion, FAK interference could effectively suppress the proliferation, invasion and metastasis of transfected SGC7901 gastric cancer cells, and could inhibit the growth and distant metastasis of gastric cancer in nude mice.

7.
Ying Yong Sheng Tai Xue Bao ; 25(1): 272-8, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24765871

RESUMO

Nitrogen (N) inputs caused by human activities potentially influences the aquatic environment. However, researches on N pollution in China are mainly discussed from the microscopic point of view, i. e. field experiment. Watershed-scale diagnosis of N pollution has just started, leading to ambiguous identification of ecological problems, pollution issues and pollution potential at watershed scale. In this paper, relationships between net anthropogenic N inputs (NANI) and riverine N flux (RNF) and factors influencing these relationships at watershed scale had been investigated. This would help diagnose ecological and environmental problems at watershed scale, understand the roles of natural climate and human activities in affecting N fluxes, and ultimately provide both theoretical and practical insights into environmental management decisions.


Assuntos
Nitrogênio/análise , Rios/química , Poluentes Químicos da Água/análise , China , Clima , Poluição Ambiental
8.
Environ Sci Pollut Res Int ; 21(8): 5678-88, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24430498

RESUMO

Many rivers in China and other newly industrialized countries have suffered from severe degradation of water quality in the context of rapid economic growth. An accounting method was developed to investigate the source and mass fluxes of the main contaminants in the Ziya River, a severely polluted and heavily modified river in a semiarid area of the North China Plain, where chemical oxygen demand (COD) and ammonia nitrogen (NH4-N) were the most important indicators of pollution. The results showed that the urban sewage with high concentration of COD and NH4-N dominated the streams, contributing to 80.7 % of the streamflow, 92.2 % of COD, and 94.5 % of NH4-N. The concentrations of COD and NH4-N in streams varied from 24.0-195.0 to 5.8-43.8 mg/L, respectively. Mass fluxes of COD and NH4-N of all pathways were quantified. Much of the polluted water was diverted to irrigation, and some eventually flowed into the Bohai Sea. Installation of adequate wastewater treatment facilities and making strict discharge standards can help improve the water quality. Our findings imply that a simple accounting method provides an extremely well-documented example for load estimation and can be useful for intervention strategies in heavily polluted and modified rivers in newly industrialized countries.


Assuntos
Rios/química , Poluentes Químicos da Água/análise , Análise da Demanda Biológica de Oxigênio , China , Monitoramento Ambiental , Nitrogênio/análise , Águas Residuárias , Qualidade da Água
9.
Transpl Immunol ; 25(4): 194-201, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21856422

RESUMO

Alloreactive memory T cells are major barriers to transplantation acceptance due to their capacity to accelerate rejection. Here, we investigated the effects of combined treatment with arsenic trioxide (As(2)O(3)) and blocking monoclonal antibodies (mAb) against CD154 and LFA-1 (anti-CD154/LFA-1) on graft survival as well as changes in pathology and immunological responses in mice with adoptively transferred allo-primed T cells. The mean survival time (MST) for the cardiac allografts in recipient mice receiving the combination of As(2)O(3) and anti-CD154/LFA-1 was significantly longer (>113.7days) compared to those receiving anti-CD154/LFA-1 (23.2days), As(2)O(3) (12.5days) alone or no treatment (5.5days). This combined strategy distinctly inhibited lymphocyte infiltration in grafts, proliferation of splenic T cells and the generation of memory T cells in spleens. Moreover, the combined treatment caused the significant down-regulation of IL-2 and IFN-γ accompanied by increased expression of TGF-ß and regulatory T cells (Tregs) in spleens, which led to long-term cardiac allograft survival in recipient mice. These results highlight the potential application of As(2)O(3) and its contribution in combination therapy with antibody blockade to delay rejection by memory T cells.


Assuntos
Transferência Adotiva , Antineoplásicos/farmacologia , Arsenicais/farmacologia , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Coração/imunologia , Coração , Óxidos/farmacologia , Linfócitos T/transplante , Animais , Anticorpos Monoclonais Murinos/farmacologia , Anticorpos Neutralizantes/farmacologia , Trióxido de Arsênio , Proliferação de Células/efeitos dos fármacos , Feminino , Sobrevivência de Enxerto/imunologia , Interferon gama/imunologia , Interleucina-2/imunologia , Transfusão de Linfócitos/métodos , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologia , Linfócitos T/imunologia , Transplante Homólogo
10.
J Environ Sci (China) ; 20(3): 326-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18595400

RESUMO

A hydroponic experiment was conducted to investigate the effects of arsenic (As) stress on growth, nutrition and As uptake, and speciation in shoots and roots of winter wheat (Triticum aestivum L.). Winter wheat has high tolerance to As. Most As is accumulated in the roots, and an As concentration of 4,421 mg/kg was observed at a solution concentration of 20 mg/L As. Arsenic concentrations in roots were approximately 40-100 times greater than those in shoots. Arsenic in winter wheat roots and shoots occurred as both As3+ and As5+ species, although As3+ was the main species in winter wheat tissues. Arsenic significantly decreased the biomass of winter wheat shoots and roots and affected absorption and transport of micro- and macro-elements in winter wheat tissue. Arsenic treatment significantly increased the concentrations of total Magnesium (Mg) and calcium (Ca) in shoots and enhanced the transport of Mg and Ca from roots to shoots but decreased potassium (K), nitrogen (N), and phosphorus (P) concentrations in both shoots and roots, particularly the concentration of P. Concentrations of iron, copper, and zinc in winter wheat shoots were negatively related to As rates, with correlation coefficients (R2) of 0.93, 0.94, and 0.97, respectively.


Assuntos
Arsênico/farmacologia , Hidroponia/métodos , Triticum/efeitos dos fármacos , Arsênico/química , Arsênico/metabolismo , Transporte Biológico/efeitos dos fármacos , Cádmio/metabolismo , Cobre/metabolismo , Ferro/metabolismo , Magnésio/metabolismo , Manganês/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Triticum/metabolismo , Zinco/metabolismo
11.
Environ Sci Pollut Res Int ; 14(7): 529-35, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18062487

RESUMO

GOAL, SCOPE AND BACKGROUND: Biosolids, i.e., treated sewage sludge, are commonly used as a fertilizer and amendment to improve soil productivity. Application of biosolids to meet the nitrogen (N) requirements of crops can lead to accumulation of phosphorus (P) in soils, which may result in P loss to water bodies. Since 1996, biosolids have been applied to a Pinus radiata D. Don plantation near Nelson City, New Zealand, in an N-deficient sandy soil. To investigate sustainability of the biosolids application programme, a long-term research trial was established in 1997, and biosolids were applied every three years, at three application rates, including control (no biosolids), standard and high treatments, based on total N loading. The objective of this study was to evaluate the effect of repeated application of biosolids on P mobility in the sandy soil. MATERIALS AND METHODS: Soil samples were collected in August 2004 from the trial site at depths of 0-10, 10-25, 25-50, 50-75, and 75-100 cm. The soil samples were analysed for total P (TP), plant-available P (Olsen P and Mehlich 3 P), and various P fractions (water-soluble, bioavailable, Fe and Al-bound, Ca-bound, and residual) using a sequential P fractionation procedure. RESULTS AND DISCUSSION: Soil TP and Olsen P in the high biosolids treatment (equivalent to 600 kg N ha(-1) applied every three years) had increased significantly (P<0.05) in both 0-10 cm and 10-25 cm layers. Mehlich 3 P in soil of the high treatment had increased significantly only at 0-10 cm. Olsen P appeared to be more sensitive than Mehlich 3 P as an indicator of P movement in a soil profile. Phosphorus fractionation revealed that inorganic P (Al/Fe-bound P and Ca-bound P) and residual P were the main P pools in soil, whereas water-soluble P accounted for approximately 70% of TP in biosolids. Little organic P was found in either the soil or biosolids. Concentrations of water-soluble P, bioavailable inorganic P (NaHCO3 Pi) and potentially bioavailable inorganic P (NaOH Pi) in both 0-10 and 10-25 cm depths were significantly higher in the high biosolids treatment than in the control. Mass balance calculation indicated that most P applied with biosolids was retained by the top soil (0-25 cm). The standard biosolids treatment (equivalent to 300 kg N ha(-1) applied every three years) had no significant effect on concentrations of TP, Mehlich 3 P and Olsen P, and P fractions in soil. CONCLUSIONS: The results indicate that the soil had the capacity to retain most biosolids-derived P, and there was a minimal risk of P losses via leaching in the medium term in the sandy forest soil because of the repeated biosolids application, particularly at the standard rate. RECOMMENDATIONS AND PERSPECTIVES: Application to low-fertility forest land can be used as an environmentally friendly option for biosolids management. When biosolids are applied at a rate to meet the N requirement of the tree crop, it can take a very long time before the forest soil is saturated with P. However, when a biosolids product contains high concentrations of P and is applied at a high rate, the forest ecosystem may not have the capacity to retain all P applied with biosolids in the long term.


Assuntos
Fósforo/química , Esgotos/química , Solo , Árvores , Carbono/química , Fracionamento Químico , Fertilizantes , Pinus , Poluição da Água/análise
12.
Di Yi Jun Yi Da Xue Xue Bao ; 25(7): 823-6, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16027078

RESUMO

OBJECTIVE: To study the changes in morphology of liver and spleen and hemodynamics of the patients with Budd-Chiari syndrome (BCS) after interventional treatment. METHODS: The dimensions of liver and spleen were detected by routine ultrasonography in 30 normal control subjects and 256 BCS patients before and after inventional therapy. Color duplex sonography was employed to measure the hemodynamic changes. RESULTS: Compared with the control group, BCS patients before interventional therapy showed obvious liver and spleen enlargements (P<0.005), specially the caudate lobe of the liver (P<0.001), which were significantly reduced 7 days after interventional treatment (P<0.005), but the spleen was still larger than that of the control group (P<0.005) even till 6 months after the therapy. Color Doppler flow imaging (CDFI) revealed local high-speed blood flow in patients with stenosis of the inferior vena cave (IVC), but color flow was not detected in patients with IVC obstruction, who had hepatic vein dilation (P<0.005) with slowed blood flow and collateral formation of in the liver, as well as decreased velocity of blood flow in the portal vein. After interventional treatment, the diameter of the involved IVC increased with blood flow restoration and the size and shape of the stent were detected clearly. The velocity of blood flow was increased in both the hepatic and portal veins (P<0.005). CONCLUSION: Interventional therapy can relieve obstruction of blood flow in the liver and improve the hemodynamics of patients with BCS.


Assuntos
Angioplastia com Balão , Síndrome de Budd-Chiari/fisiopatologia , Síndrome de Budd-Chiari/terapia , Circulação Hepática , Síndrome de Budd-Chiari/diagnóstico por imagem , Humanos , Fígado/diagnóstico por imagem , Veia Porta/fisiopatologia , Stents , Ultrassonografia , Veia Cava Inferior/fisiopatologia
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