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1.
Huan Jing Ke Xue ; 42(11): 5394-5404, 2021 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-34708978

RESUMEN

Scientific identification of runoff output characteristics of different land use patterns is the premise of controlling non-point source pollution in watersheds. The hydrology and output process of non-point source pollutants of forest, planting, and construction land with different rainfall characteristics were observed using a micro-watershed in a low mountain and hilly region of Southern China. The results showed that land use affected the hydrological characteristics and water quality processes of runoff. The characteristics of runoff generation time and cumulative rainfall under typical rainfall conditions were as follows:construction land(9 min, 2.0 mm), planting land(35 min, 11.4 mm), and forest land(108 min, 24 mm). There were significant differences in the three land use types in the pollution output process characteristics, such as pollutant concentration of total suspended matter(TSS), total nitrogen(TN) and phosphorus(TP), their components, N/P ratio change, and output intensity. Under typical rainfall, different land use types had similar pollution output stages, the mass concentrations of TSS, TN, and TP in the initial runoff were high, and then gradually stabilized. In addition, the first 30 min of the flow generation process contributed to the TSS, TN, and TP loads within the 23%-43% range. At the annual scale, there were significant differences between the contribution rate of each land use type to TN and TP load and ratio per unit area; the highest contribution to total pollution load was planting land(57% and 45%), while the highest in pollution load per unit area was construction land(9.50-12.50). The results also showed that the distribution of key non-point source areas had different spatial and temporal dynamics, which was comprehensively determined by the land use types in catchment units, the characteristics of annual rainfall, among other factors. With the increase in rainfall, the main contribution non-point source pollution in the micro-watershed changed from construction land to planting land. Targeted ecological interception strategies should be implemented based on the distribution characteristics of key source areas and characteristics of underlying surface runoff production process.


Asunto(s)
Contaminación Difusa , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Nitrógeno/análisis , Fósforo/análisis , Suelo , Movimientos del Agua , Contaminantes Químicos del Agua/análisis
2.
Huan Jing Ke Xue ; 42(7): 3328-3337, 2021 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-34212658

RESUMEN

At present, there are few reports about how impervious surface microstructure characteristics affect the runoff output process of street dust. Based on field observations of 12 rainfall events, this study quantified the microstructure characteristics of impervious surfaces by structural depth (roughness) and analyzed the correlation between roughness and accumulation characteristics of street dust on sunny days as well as scouring characteristics in rainy days. The results show that the roughness of the underlying surface notably affects dust accumulation on sunny days and scouring in rainy days. The correlation between roughness and street dust accumulation (r=0.664, P<0.01) was enhanced on sunny days, and the correlation between roughness and street dust erosion (r=0.527, P<0.01) was enhanced by rainfall. The correlation of street dust accumulation and roughness of each particle size segment increased as particle size increased (0.529 ≤ r<0.757), and the correlation between street dust scouring amount and roughness decreased as particle size increased (0.603 > R > 0.209). By establishing the linear regression model of roughness and rainfall, the cumulative pollution load of TSS in rainfall runoff can be well predicted. The effects of roughness and rainfall on the cumulative load of grain sizes<20 µm and >250 µm are significant. These results elucidate the role of roughness and rainfall analysis in predicting surface runoff pollution load characteristics, which can provide new information for predicting and evaluating urban non-point source pollution.


Asunto(s)
Movimientos del Agua , Contaminantes Químicos del Agua , Polvo/análisis , Monitoreo del Ambiente , Lluvia , Contaminantes Químicos del Agua/análisis
3.
Breast ; 34: 115-121, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28577471

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias de la Mama Masculina/mortalidad , Neoplasias de la Mama/mortalidad , Carcinoma/mortalidad , Neoplasias Hepáticas/mortalidad , Neoplasias Pulmonares/mortalidad , Factores de Edad , Anciano , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama Masculina/metabolismo , Neoplasias de la Mama Masculina/patología , Carcinoma/metabolismo , Carcinoma/secundario , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Receptores de Estrógenos , Receptores de Progesterona , Programa de VERF , Factores Sexuales , Tasa de Supervivencia , Estados Unidos/epidemiología
4.
Di Yi Jun Yi Da Xue Xue Bao ; 25(7): 823-6, 2005 Jul.
Artículo en Zh | MEDLINE | ID: mdl-16027078

RESUMEN

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.


Asunto(s)
Angioplastia de Balón , Síndrome de Budd-Chiari/fisiopatología , Síndrome de Budd-Chiari/terapia , Circulación Hepática , Síndrome de Budd-Chiari/diagnóstico por imagen , Humanos , Hígado/diagnóstico por imagen , Vena Porta/fisiopatología , Stents , Ultrasonografía , Vena Cava Inferior/fisiopatología
5.
Ying Yong Sheng Tai Xue Bao ; 26(6): 1831-9, 2015 Jun.
Artículo en Zh | MEDLINE | ID: mdl-26572039

RESUMEN

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.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Fertilizantes , Nitrógeno/análisis , China , Ecosistema , Actividades Humanas , Humanos , Ríos , Urbanización
6.
Oncol Lett ; 9(2): 595-603, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25621028

RESUMEN

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.
Artículo en Zh | MEDLINE | ID: mdl-24765871

RESUMEN

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.


Asunto(s)
Nitrógeno/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , China , Clima , Contaminación Ambiental
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