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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(9): 2495-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22097856

RESUMO

It is difficulties for the computer simulation method to study radiation regime at large-scale. Simplified coniferous model was investigated in the present study. It makes the computer simulation methods such as L-systems and radiosity-graphics combined method (RGM) more powerful in remote sensing of heterogeneous coniferous forests over a large-scale region. L-systems is applied to render 3-D coniferous forest scenarios, and RGM model was used to calculate BRF (bidirectional reflectance factor) in visible and near-infrared regions. Results in this study show that in most cases both agreed well. Meanwhile at a tree and forest level, the results are also good.


Assuntos
Simulação por Computador , Florestas , Traqueófitas , Modelos Teóricos , Análise Espectral , Árvores
2.
Oncol Lett ; 21(3): 187, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33574926

RESUMO

Histone H2AX (H2A.X) is a variant of the histone H2A family. Phosphorylation of H2A.X is a marker of DNA strand breaks and the presence or absence of H2A.X is closely related to tumor susceptibility and drug resistance. The present study found that the activity of the serine/threonine kinase Akt was negatively associated with H2A.X phosphorylated at the Ser16 site (H2A.X S16ph), but the mechanism of the inverse relationship remains elusive. The aim of the present study was to elucidate the mechanism of action between Akt and H2A.X S16ph and the exact role of this mechanism. Western blot analysis was performed to detect the regulatory association between p-Akt and H2A.X S16ph/p-RSK2, and immunoprecipitation and chromatin immunoprecipitation were performed to prove that Akt, RSK2 and H2A.X combine and interact in human breast cancer cells. The changes of cellular proliferation and migration induced by the interaction of Akt, RSK2 and H2A.X was determined by MTT, soft agar colony formation and cell migration experiments. The effect of interaction of Akt, RSK2 and H2A.X on cancer-promoting genes, such as PSAT-1 was determined via reverse transcription-quantitative PCR analysis. The current study indicated that the serine/threonine kinase ribosomal S6 kinase 2 (RSK2) as a kinase of H2A.X could be phosphorylated by Akt at Ser19 site. Moreover, Akt positively regulated the phosphorylation of RSK2 to inhibit phosphorylation of H2A.X, thereby affecting the affinity between RSK2 and substrate histone, promoting the survival and migration of breast cancer cells. In conclusion, Akt-mediated phosphorylation of RSK2 regulated the phosphorylation of H2A.X, thereby promoting oncogenic activity. This finding provides new insights to understand the pathogenesis and treatment mechanisms of breast cancer.

3.
Ying Yong Sheng Tai Xue Bao ; 32(12): 4203-4211, 2021 Dec.
Artigo em Zh | MEDLINE | ID: mdl-34951261

RESUMO

Soil moisture is an important hydrological parameter and a basic element for research in water cycle and climate change. Using hourly recorded soil moisture data of 374 stations from the new generation of automatic soil moisture encryption observation network constructed by China Meteo-rological Administration, we analyzed the spatial and temporal variations of soil moisture in North China from 2013 to 2019 and the relationship with precipitation and temperature. The results showed that soil moisture in 10-100 cm layer decreased fluctuatly as a whole, with the decreasing at the 100 cm being serious. The spatial distribution of soil moisture at different depths was characterized by high in the southeast and low in the northwest. About 63% of the surface layer was short of moisture. Soil moisture at different depths changed significantly with the seasons. In summer, soil moisture of each layer reached the highest and soil entropy of each layer was suitable, while it reached a low point in spring. Soil moisture was closely correlated with precipitation and temperature, but the correlation got weaker gradually with the increase of soil depth. Soil moisture was more sensitive to precipitation than to temperature.


Assuntos
Solo , Água , China , Estações do Ano , Temperatura , Água/análise
5.
Chin J Integr Med ; 23(8): 574-580, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28028716

RESUMO

OBJECTIVE: To comprehensively evaluate the health status of 6 volunteers from the Mars 500 Project through analyzing their pulse graphs and determining the changes in cardiovascular function, degree of fatigue and autonomic nervous function. METHODS: Six volunteers were recruited; all were male aged 26-38 years (average 31.83±4.96 years). Characteristic parameters reflflecting the status of cardiovascular functions were extracted, which included left ventricular contraction, vascular elasticity and peripheral resistance. The degree of fatigue was determined depending on the difference between the calendar age and biological age, which was calculated through the analysis of blood pressure value and characteristic parameters. Based on the values of pulse height variation and pulse time variation on a 30-s pulse graph, autonomic nervous function was evaluated. All parameters examined were marked on an equilateral polygon to form an irregular polygon of the actual fifigure, then health status was evaluated based on the coverage area of the actual fifigure. RESULTS: The results demonstrated: (1) volunteers developed weakened pulse power, increased vascular tension and peripheral resistance, and slight decreased ventricular systolic function; (2) the degree of fatigue was basically mild or moderate; and (3) autonomic nervous function was excited but generally balanced. CONCLUSIONS: These volunteers were in the state of sub-health. According to Chinese medicine theories, such symptoms are mainly caused by the weakening of healthy qi, Gan (Liver) failing in free coursing, and disharmony between Gan and Wei (Stomach), which manifests as a weak and string-like pulse.


Assuntos
Nível de Saúde , Pulso Arterial/métodos , Voluntários , Sistema Nervoso Autônomo/fisiologia , Fadiga/fisiopatologia , Testes de Função Cardíaca , Humanos , Contração Miocárdica , Fatores de Tempo , Resistência Vascular/fisiologia , Função Ventricular/fisiologia
7.
Anal Chim Acta ; 612(2): 136-43, 2008 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-18358858

RESUMO

A highly selective molecularly imprinted adsorptive resin for ligustrazine was prepared by melamine-urea-formaldehyde (MUF) gel. In the experiments, two pieces of MUF gel were synthesized firstly; one was added ligustrazine hydrochloride as the template molecule in it to prepare the imprinted adsorptive resin, and the other was not. Scanning electron microscopy (SEM) revealed that both resins were the porous with a network structure whether or not it was added template molecule. The imprinted adsorptive resin had an absorbability of 85.22% measured by a 200 mg L(-1) solution of ligustrazine hydrochloride at room temperature. The resin of MUF without template, on the other hand, displayed an adsorption capacity of almost zero. It illuminated the imprinted adsorptive resin formed ligustrazine recognition sites when the template molecule had been eluted. In the present paper, ligustrazine was effectively separated and enriched from herbs by using a solid-phase adsorptive column filled with the imprinted adsorptive resin. Its eluate, obtained from three kinds of solvents, was analyzed by GC-MS, and the results indicated that the imprinted adsorptive resin showed a high selectivity for ligustrazine. This is believed to be beneficial for extracting natural and highly purified ligustrazine.


Assuntos
Ligusticum/química , Medicina Tradicional Chinesa , Impressão Molecular , Pirazinas/química , Pirazinas/isolamento & purificação , Adsorção , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Microscopia Eletrônica de Varredura , Estrutura Molecular , Extração em Fase Sólida
8.
Zhonghua Er Ke Za Zhi ; 45(8): 592-8, 2007 Aug.
Artigo em Zh | MEDLINE | ID: mdl-18021533

RESUMO

OBJECTIVE: To assess the efficacy and safety of interferon-alpha (IFN-alpha) in children with Hepatitis B e antigen-positive chronic hepatitis B virus infection. METHODS: PubMed and Chinese Biomedical Database were searched from the beginning of operation of the databases to April 2006, and the references of eligible studies were manually screened. Randomized controlled trials (RCTs) published in the English and Chinese literature comparing interferon-alpha with non-antiviral interventions (placebo or no treatment) in children with hepatitis B e antigen-positive chronic hepatitis B virus infection were eligible for inclusion. Studies were included if patients were treated for at least 3 months and followed-up for at least 6 months after cessation of therapy. Two investigators independently assessed the quality and extracted the data. The methodological quality of trails was assessed by the Jadad-scale plus allocation concealment. Heterogeneity was examined by Chi-square test. Fixed effects model or random effects model were used to pool the data. Sensitivity analyses were used for the treatment course. RESULTS: Ten randomized controlled studies with a total of 542 children chronic HBV carriers who were positive for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were identified. It was found by the meta-analysis that, compared with the control, at the end of the follow-up period, IFN-alpha could still significantly clear HBeAg [31.1% vs. 12.4%, odds ratio (OR): 3.17, 95% CI (2.00, 5.02), P < 0.000 01], clear HBV-DNA [33.9% vs. 16.2%, OR: 2.59, 95% CI (1.70, 3.96), P < 0.0001], clear HBsAg [5.5% vs. 1.2%, OR: 3.44, 95% CI (1.20, 9.89), P = 0.02], normalize ALT [43.0% vs. 27.7%, OR: 1.99, 95% CI (1.16, 3.42), P = 0.01], and achieve HBeAg seroconversion [30.4% vs. 12.8%, OR: 2.90, 95% CI (1.56, 5.39), P = 0.0008], but was not effective in HBsAg seroconversion [1.9% vs. 0, 95% CI (0.42, 18.13), P = 0.29]. CONCLUSIONS: Interferon-alpha might be efficacious in clearance of HBeAg, HBV-DNA and HBsAg, normalization of ALT, and achievement of HBeAg seroconversion in children with chronic hepatitis B. Little evidence is available on HBsAg seroconversion. Further RCTs of high-quality and sufficient number of cases are needed for confirmation of the clinical efficacy of IFN-alpha in chronic hepatitis B in children.


Assuntos
Antivirais/uso terapêutico , Seguimentos , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adolescente , Criança , Pré-Escolar , DNA Viral/análise , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Lactente , Masculino , Placebos , Resultado do Tratamento
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