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1.
J Environ Manage ; 262: 110310, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250793

RESUMEN

Identifying the spatio-temporal variations of evapotranspiration (ET) from its components (soil evaporation and plant transpiration) can greatly improve our understanding of water-cycle and biogeochemical processes. However, partitioning evapotranspiration into evaporation (E) and transpiration (T) at regional scale with high accuracy still remains a challenge. This study has aimed to reveal the spatio-temporal variations of evapotranspiration and its components by using an improved Shuttleworth-Wallace (SWH) model to partition ET in the Yellow River Basin during 1981-2010. The environmental factors affecting the spatial and temporal variations of evapotranspiration and its components were also assessed. Results showed that the mean annual ET, T and E in the Yellow River Basin were 372.18 mm, 179.64 mm, and 192.54 mm, respectively, over the last 30 years. The spatial pattern of mean annual ET and T displayed a decreasing trend from southeast to northwest in the Yellow River Basin, and the temporal variation showed a significant increasing trend with rates of 1.72 mm yr-1 and 1.54 mm yr-1, respectively. It meant that T accounted for the variations of ET, while E showed no significant changes in recent decades. Moreover, the normalized differential vegetation index (NDVI) and temperature were identified as the main factors controlling the variations of ET and T in the Yellow River Basin. Among them, the area with NDVI as the dominant factor for ET and T could reach 63.82% and 78.47% of the whole basin respectively. However, the variations of E were affected by complex factors, and evaporation in the western alpine region was mainly controlled by temperature. Our findings are expected to not only have implications for developing sustainable policies of water management and ecological restoration in this region, but also provide valuable insight in methodology of ET partitioning in regional or global scale.


Asunto(s)
Transpiración de Plantas , Ríos , China , Suelo , Temperatura , Agua
2.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3367-3376, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30325162

RESUMEN

Construction of ecological network is important for improving urban ecological environment under the scenarios of rapid urbanization. We extracted the core area with good connectivity as the ecological sources with the methods of morphological spatial pattern analysis (MSPA) and landscape index with Guangzhou City as the study area. The ecological network was then constructed by minimal cumulative resistance (MCR) model and was quantitatively analyzed by gravity model and connectivity indices. After that, an optimized ecological network was finally constructed. The results showed that ten core patches could be used as ecological sources. In addition, eighteen important corridors as well as twenty-seven general corridors were identified, which were mainly distributed in the northeast part of the city. Five more ecological sources and thirteen more planning corridors were suggested under the optimized ecological network. Our results indicated that forests were the main composition of ecological corridors. The appropriate width for the important corridor and planning corridor was 60-100 m and 30-60 m, respectively. Our results provide scientific guidance for designing urban ecological network.


Asunto(s)
Ecosistema , China , Ciudades , Planificación de Ciudades , Conservación de los Recursos Naturales , Bosques , Análisis Espacial , Urbanización
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 32-6, 2017 01.
Artículo en Chino | MEDLINE | ID: mdl-30192462

RESUMEN

In this paper, a series of CaMoO4 phosphor co-doped rare earth ions were prepared with chemistry co-precipitation method. The concentration of Pr(3+)/Tb(3+) and temperature had obvious influence on the luminescent properties. The crystal structures and spectrum characteristics of the samples were identified with X-ray powder diffraction (XRD) and fluorescence spectrophotometer (PL). According to XRD analysis, the main diffraction peaks of samples are consistent with the standard card (JCPDS 29-0351) of the diffraction peak data. This showed doped rare earth ions did not change matrix lattice structure. The emission spectrum excited by 275 nm exhibit sharp lines peaking at 488, 560, 621 and 560 nm assigned to the (3)P(0)­(3)H(4), (3)P(0)­(3)H(5),(1)D(2)­(3)H(4) and (3)P(0)­(3)F(2) transitions of the Pr(3+) ions. The intensity of fluorescence reached the strongest when the concentration of the doping amount was 3%. The optimum calcination temperatures of CaMoO(4)∶0.03Pr(3+) and CaMoO(4)∶0.05Tb(3+) were 800 and 600 ℃. Furthermore, the intensity of excitation spectra and emission spectra are dependent on the concentration of the doping amount. The emission spectra intensities of CaMoO(4)∶Pr(3+) phosphors decrease and CaMoO(4)∶Tb(3+) phosphors firstly increase and then decrease because of concentration quenching effect with increasing Pr(3+) and Tb(3+) concentration. In addition, the luminescence properties of Pr(3+) ion in CaMoO(4)∶0.03Pr(3+), yTb(3+) system could be evidently improved with co-doping of Tb(3+) ions which was due to the efficient energy transfer process from Tb(3+) to Pr(3+) ions.

4.
Oncol Lett ; 10(5): 3018-3020, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26722282

RESUMEN

Hemophilia is a hereditary disease with impaired blood coagulation due to a genetic deficiency of blood coagulation factors. Hemophilia often causes spontaneous life-threatening bleeding, so patients with hemophilia are often not suitable for any surgery that may cause iatrogenic bleeding and threaten the life of the patient. Therefore, surgery in lung cancer patients with hemophilia is extremely rare. The present study reported the case of a lung cancer patient with hemophilia who presented with a persistent cough. A mass was revealed by computed tomography and the patient underwent a successful thoracoscopic right lower lobectomy. The study discusses the patient's diagnosis and treatment options for hemophilia A and lung cancer, including indications for thoracoscopic lobectomy, pre-operative preparation and post-operative care, and other treatment options are discussed. The literature is also reviewed on this subject.

5.
Int J Clin Exp Pathol ; 8(10): 12961-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26722491

RESUMEN

To explore the relationship between death associated protein kinase (DAPK) gene promoter methylation and gefitinib resistance in Lung adenocarcinoma cell lines. EGFR-mutation lung adenocarcinoma cell lines PC9 and the gefitinib-resistant with T790M Mutation cell lines PC9/GR were chosen as cell models, and PC9/GR were treated with 5-aza-CdR (1 µmol/L). The experiments were divided into three groups: PC9 group, PC9/GR group and PC9/GR with 5-Aza-CdR pretreatment group. Treat three groups cell with different concentrations gefitinib, the cell proliferation was determined by MTT assay. The apoptotic rates were detected by flow cytometry. The methylation of DAPK gene promoter region was examined by methylation-specific PCR (MSP). The expressions of DAPK protein were detected by Western blot. MTT results showed that the half maximal inhibitory concentration (IC50) of PC9 and PC9/GR cell lines increase from 0.12 µmol/L to 8.52 µmol/L. But after treated with 5-aza-CdR, the IC50 of PC9/GR cell lines decrease to 4.35 µmol/L, and the resistance index (RI) decrease from 71 to 36 (P<0.05). Flow cytometry results showed that the apoptosis rate were 24.80% ± 0.28%, 12.70% ± 0.31%, 19.8% ± 0.15% respectively. MSP results showed that DAPK gene promoter region was un-methylated in PC9 cells and methylated in PC9/GR cells, when treated with 5-aza-CdR, DAPK gene promoter region was partly methylated in PC9/GR cells (P<0.05). Western blot results showed that the levels of DAPK protein were reduced significantly in PC9/GR cell lines compared with PC9, and after treated with 5-aza-CdR, the expression levels of DAPK protein in PC9/GR were increased (P<0.05). In conclusion, DAPK gene promoter methylation may contribute to the downregulation of DAPK gene and protein, and consequently affect the sensitivity of gefitinib in lung adenocarcinoma lines, induced gefitinib resistance. But 5-Aza-CdR can reverse gefitinib resistance by demethylation of DAPK gene promoter.


Asunto(s)
Adenocarcinoma/genética , Azacitidina/farmacología , Metilación de ADN/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Pulmonares/genética , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Azacitidina/análogos & derivados , Western Blotting , Línea Celular Tumoral , Proteínas Quinasas Asociadas a Muerte Celular/genética , Resistencia a Antineoplásicos/genética , Citometría de Flujo , Gefitinib , Humanos , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas/genética , Quinazolinas/farmacología
6.
Sci Rep ; 4: 7425, 2014 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-25502776

RESUMEN

Calstabin2 is a component of the cardiac ryanodine receptor (RyR2) macromolecular complex, which modulates Ca(2+) release from the sarcoplasmic reticulum in cardiomyocytes. Previous reports implied that genetic deletion of Calstabin2 leads to phenotypes related to cardiac aging. However, the mechanistic role of Calstabin2 in the process of cardiac aging remains unclear. To assess whether Calstabin2 is involved in age-related heart dysfunction, we studied Calstabin2 knockout (KO) and control wild-type (WT) mice. We found a significant association between deletion of Calstabin2 and cardiac aging. Indeed, aged Calstabin2 KO mice exhibited a markedly impaired cardiac function compared with WT littermates. Calstabin2 deletion resulted also in increased levels of cell cycle inhibitors p16 and p19, augmented cardiac fibrosis, cell death, and shorter telomeres. Eventually, we demonstrated that Calstabin2 deletion resulted in AKT phosphorylation, augmented mTOR activity, and impaired autophagy in the heart. Taken together, our results identify Calstabin2 as a key modulator of cardiac aging and indicate that the activation of the AKT/mTOR pathway plays a mechanistic role in such a process.


Asunto(s)
Miocardio/metabolismo , Proteínas de Unión a Tacrolimus/fisiología , Envejecimiento , Animales , Autofagia , Calcineurina/metabolismo , Células Cultivadas , Senescencia Celular , Hipertrofia Ventricular Izquierda/patología , Masculino , Ratones de la Cepa 129 , Ratones Noqueados , Miocardio/patología , Miocitos Cardíacos/fisiología , Transducción de Señal , Remodelación Ventricular
7.
J Int Med Res ; 41(5): 1437-44, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24065453

RESUMEN

OBJECTIVE: To investigate the levels of microRNA-210 (miR-210) in the serum of patients with nonsmall-cell lung cancer (NSCLC) and to determine whether there was a correlation with the prognosis of NSCLC patients following cisplatin-based chemotherapy. METHODS: Quantitative real-time reverse transcription-polymerase chain reaction was used to measure the serum levels of miR-210 in patients with NSCLC and healthy age-matched control subjects. Correlations between serum miR-210 levels and clinicopathological factors and prognosis were investigated. RESULTS: Serum miR-210 was significantly upregulated in 60 patients with NSCLC compared with 30 healthy control subjects. Higher serum miR-210 levels were significantly correlated with the clinical stage and the presence of regional lymph node metastasis in patients with NSCLC. Serum miR-210 levels in patients that achieved a partial response following cisplatin-based chemotherapy were significantly lower than in patients with stable or progressive disease, and were similar to those in healthy control subjects. CONCLUSIONS: These findings suggest that serum miR-210 levels might be a novel diagnostic and prognostic marker of NSCLC.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , MicroARNs/genética , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/sangre , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Casos y Controles , Cisplatino/uso terapéutico , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico
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