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1.
J Environ Public Health ; 2020: 4749765, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32377205

RESUMEN

The increase of urbanization level has led to the rapid increase of impervious surface area (ISA). The aim of this work is to clarify the relationship between the ISA and water quality and lay a foundation for the improvement and protection of the water quality in the basin. Taking the Fuxian Lake Basin in Yunnan Province as an example, based on the Landsat ETM+ remote sensing image and the Gram-Schmidt (GS) image fusion algorithm, the four-terminal model and the linear spectral mixture model (LSMM) were used to extract the impervious surface of the watershed from 2006 to 2015. And statistical methods were used to distinguish its relationship with water quality. The results show that the four-terminal model and the linear spectral mixture model can effectively extract the impervious surface information of the Fuxian Lake Basin. The average root mean square error (RMS) of the image decomposition results from 2006 to 2015 was less than 0.02. In the past 10 years, the ISA has changed significantly in the Fuxian Lake Basin. The ISA showed an overall upward trend from 2006 to 2015. It increased from 24.73 km2 in 2006 to 35.14 km2 in 2015, an increase of 10.81 km2. From the value anomaly, the ISA in 2006 and 2009 is lower than the multiyear average, and those in the other years are higher than the multiyear average. The percentage of ISA in the basin was significantly positively correlated with Chemical Oxygen Demand-Mn (CODMn) and total phosphorus (TP) (r is 0.772, 0.763), and the correlation in the flooding season was greater than that in the dry season. The ISA threshold for water quality deterioration is around 10% in the Fuxian Lake Basin. Reducing ISA coverage, controlling ISA to less than 10%, and preventing nonpoint source pollution during flooding season will be the best measures to effectively improve the water quality environment in the basin.


Asunto(s)
Monitoreo del Ambiente , Lagos/química , Contaminación Química del Agua/análisis , Análisis de la Demanda Biológica de Oxígeno , China , Monitoreo del Ambiente/métodos , Fenómenos Geológicos , Modelos Teóricos , Fósforo/análisis , Estaciones del Año , Urbanización , Contaminación Química del Agua/prevención & control
2.
Zhonghua Wai Ke Za Zhi ; 32(12): 712-4, 1994 Dec.
Artículo en Chino | MEDLINE | ID: mdl-7774415

RESUMEN

UNLABELLED: The mRNA expression of WT1 gene was examined by Northern blot and Dot blot hybridization in 13 Wilm's tumors of varying histology, 2 normal kidneys (1 and 5 years of age) and 1 fetal kidney (5 months of gestation). RESULTS: (1) WT1 gene expression was much higher in fetal kidney than in normal kidney of children; (2) Wilm's tumors which were predominantly epithelial or blastemal expressed high amounts of WT1mRNA, whereas predominantly stromal tumors expressed low amounts (P < 0.01). The data suggests that (1) there is a relationship between WT1 gene expression and cellular differentiation in kidney development; (2) low level expression of WT1mRNA results in disruption of cell differentiation and development of Wilms' tumor which shows stromal-predominant histology.


Asunto(s)
Genes del Tumor de Wilms , Neoplasias Renales/genética , ARN Mensajero/metabolismo , Tumor de Wilms/genética , Northern Blotting , Diferenciación Celular/genética , Niño , Preescolar , Femenino , Expresión Génica , Humanos , Lactante , Riñón/citología , Masculino , ARN Neoplásico/metabolismo
3.
Zhonghua Wai Ke Za Zhi ; 29(5): 298-9, 334, 1991 May.
Artículo en Chino | MEDLINE | ID: mdl-1680615

RESUMEN

The authors detected the DNA content of testicular cells in 25 cryptorchidism patients by flow cytometric analysis and discussed the clinical management of the disease. The patients were aged from 13 months to 9 years. Of the 25 patients one showed a tetraploid (4C), 24 diploid (2C), and no haploid (1C) in this series. No significant difference between bilateral and single testis was demonstrated but there was a minor difference in the ratio of 2C and 4C cells between those groups younger and older than 3 years. This finding indicated that in the group older than 3 years of age the testes become fibrotic and sclerotic. The evidence also confirms that the operation should be performed before age of 3 years.


Asunto(s)
Criptorquidismo/genética , ADN/análisis , Testículo/citología , Niño , Preescolar , Diploidia , Citometría de Flujo , Humanos , Lactante , Masculino
4.
Zhonghua Zhong Liu Za Zhi ; 9(4): 295-7, 1987 Jul.
Artículo en Chino | MEDLINE | ID: mdl-3678021

RESUMEN

Ultrastructures of 11 cases of neuroblastoma and ganglioneuroblastoma were observed. Ultrastructurally, the neuroblastoma could be classified into four types: immature, poorly differentiated, differentiated and ganglioneural cell. Neurosecretory granules (NSG) of round or oval shapes with various diameters in the tumor cells and neural processes were observed. The presence of NSG in the tumor tissue is one of the pathognomic features for neuroblastoma. Comparing and study of the relation between the ultrastructural findings and the excretory patterns of the urinary catecholamine as well as the prognosis, it was shown that the tumor of the differentiated type and the presence of abundant NSG lead to a good prognosis. Some slight differences in ultrastructure were found in neuroblastoma specimens from children of various ages. Infants under 18 months had a longer survival time, which is related to the differentiation and other features of the tumor cells.


Asunto(s)
Ganglioneuroma/ultraestructura , Neuroblastoma/ultraestructura , Factores de Edad , Catecolaminas/orina , Niño , Preescolar , Gránulos Citoplasmáticos/ultraestructura , Humanos , Lactante , Neuroblastoma/clasificación , Pronóstico
5.
Zhonghua Zhong Liu Za Zhi ; 8(2): 118-21, 1986 Mar.
Artículo en Chino | MEDLINE | ID: mdl-3769741

RESUMEN

From 1959 to 1982, 98 patients with neuroblastoma were treated in our hospital. Seventy-eight were diagnosed by pathology and 69 (88.5%) were followed for 1 approximately 18 years. 50(51%) had already had distant metastasis (22, to bone) on admission. Operation was performed on 53 patients (total excision on 18, partial excision on 11 and biopsy on 24 patients). The 1 and 15 year survival rates were 31.4% and 12.9%. The survival curve levelled off from the second year of the operation and remained unchanged around 20% up to the tenth year. Lesions in early stage (without metastasis) as treated by total excision gave better results. For patients with advanced lesions, no remarkable effect was found in the supplementary use of chemotherapy. We suggest that the intravenous pyelogram, bone marrow aspiration and vanillylmandelic acid (VMA) assay be made before operation. Urine VMA assay is a criterion not only for early diagnosis but also for follow-up and detecting recurrence before clinical manifestations become apparent. Long-term follow up is crucial for neuroblastoma patients.


Asunto(s)
Neoplasias del Mediastino/terapia , Neuroblastoma/terapia , Neoplasias Retroperitoneales/terapia , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Neoplasias del Mediastino/diagnóstico , Neuroblastoma/diagnóstico , Pronóstico , Neoplasias Retroperitoneales/diagnóstico , Estudios Retrospectivos
6.
Biomed Chromatogr ; 1(1): 7-11, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3506818

RESUMEN

A method for determining serum catecholamine metabolites such as vanillylmandelic acid (VMA), 3-methoxy-4-hydroxyphenyl glycol (MHPG) and homovanillic acid (HVA) in neuroblastoma by using high performance liquid chromatography and electrochemical detector is described. The separation of catecholamine metabolites was performed on a reverse phase column with an eluting system containing citric acid-potassium hydrogen phosphate buffer and methanol as the organic modifier. The experimental results showed that VMA and HVA levels in the serum of neuroblastoma patients were 15-30 times higher than that of the normal control group. The same phenomenon also occurred in patients with stage II neuroblastoma. Serum VMA, MHPG and HVA levels reduced to normal in patients suffering from neuroblastoma after surgery. Serum catecholamine metabolites analysed by using HPLC/ECD is more simple, sensitive and reliable than that by usual urine assay and might be used for the diagnosis of neuroblastoma even in early stage.


Asunto(s)
Biomarcadores de Tumor/sangre , Glicoles/sangre , Ácido Homovanílico/sangre , Metoxihidroxifenilglicol/sangre , Neuroblastoma/sangre , Ácido Vanilmandélico/sangre , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Electroquímica , Femenino , Humanos , Lactante , Masculino , Neuroblastoma/diagnóstico
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