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1.
Pak J Med Sci ; 36(7): 1523-1528, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33235568

RESUMO

OBJECTIVE: To observe the changes of lipid metabolism, blood glucose level and insulin sensitivity in patients with Type-2 diabetes after progressive weight loss of their body weight, so as to lay a theoretical foundation for diabetes treatment and education in the future. METHODS: One hundred obese patients with Type-2 diabetes (BMI ≥ 25 kg/m2) who visited the endocrinology department of our hospital from April 2017 to April 2018 were given diabetes health education, diabetic diet, exercise and other measures to control their weight. The changes of blood glucose, blood lipid, insulin level and insulin release test before weight loss (T1), and at the time points of weight loss reached 5% (T2), 10% (T3) and 15% (T4) were recorded respectively to understand the influence of progressive weight loss on relevant indexes of patients. RESULTS: With the decrease of body weight, the differences of TC, TG, LDL-C and HDL-C at different weight loss points were significant (p < 0.05), and the changes of fasting blood glucose in 5% and 10% weight loss were significant (p = 0.02). The 2h postprandial blood glucose showed the most significant difference when the weight loss reached 15% (p = 0.00). There was no statistical difference in the change of glycosylated hemoglobin among different weight loss points (p = 0.08). When the weight loss reached 10%, the blood insulin level was significantly lower than that before the weight loss, while the insulin level was not significantly changed when the weight loss reached 15%, but the peak of secretion was shifted forward. It is suggested that insulin sensitivity gradually increases with weight loss. CONCLUSION: Obese patients with Type-2 diabetes can benefit from weight loss, with abnormal blood glucose and lipid metabolism improved, insulin resistance relieved, and insulin sensitivity increased.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(5): 1299-303, 2013 May.
Artigo em Zh | MEDLINE | ID: mdl-23905340

RESUMO

Folate receptor (FR) is particularly upregulated in many epithelial cancer cells membrane and limited distribution is found in normal tissues. In the present work, the folic acid protected gold nanoparticles (FA-GNPs) were synthesized by a simple and quick method, in which chloroauric acid (HAuCl4) was reduced by sodium borohydride (NaBH4) in the presence of FA is used as stabilizer. UV-Visible spectroscopy and transmission electron microscopy (TEM) were used to characterize the shape and size distribution of the produced FA-GNPs. X-ray photoelectron spectroscopy and cell experiment were employed to confirm the immobilization of FA and GNPs. The results showed that FA-GNPs have a good size distribution in the 3-5 nm diameter range. Moreover, it is very stable even in solution with high concentration of salt (up to 3.5% NaCl), and even high speed centrifuges of 25 000 r x min(-1) could not cause aggregation. The nanoparticles could be used to detect cancer cells.


Assuntos
Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Ouro/química , Nanopartículas Metálicas/química , Espectroscopia Fotoeletrônica/métodos , Linhagem Celular Tumoral , Humanos , Análise Espectral/métodos
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(10): 2714-7, 2012 Oct.
Artigo em Zh | MEDLINE | ID: mdl-23285872

RESUMO

Steady-state spectroscopy is prevailing for complementary tissue structural and functional information extraction The goal of the present study is to experimentally validate the merit of this technique for optical properties and intrinsic fluorescence extraction from tissue mimicking phantoms. Phantom studies were carried out in which HbO2 was used as absorber, polystyrene sphere was used as scatterer, and stilbene was used for fluorescence emission Two sets of phantoms corresponding to two absorption levels and one scattering level were made, and 4 fluorophore concentrations were titrated in each set. The results indicate that both optical properties and intrinsic fluorescence can be extracted with high accuracy, implying that it's feasible to extract complementary structural and functional information with steady-state spectroscopy.


Assuntos
Algoritmos , Hemoglobinas/química , Espectrometria de Fluorescência/métodos , Análise Espectral/métodos , Simulação por Computador , Método de Monte Carlo , Poliestirenos/química , Espectrometria de Fluorescência/instrumentação , Estilbenos/química
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(10): 2749-52, 2012 Oct.
Artigo em Zh | MEDLINE | ID: mdl-23285880

RESUMO

Blood flow plays an important role in clinical diagnosis and treatment, and noninvasive measurement of blood flow is the expectation of both doctors and patients. In the present work, the authors employed near-infrared diffuse correlation spectroscopy (DCS) method to measure blood flow noninvasively. The relationship between speckle intensity fluctuations of the scattering light and moving blood cells in tissue was theoretically analyzed. A theoretical model and blood flow measurement system were built. Blood flow was derived by calculating the electric field temporal autocorrelation function of speckle on tissue surface. Forearm blood flow was measured in healthy human subject during cuff inflation and deflation. Experimental results show that noninvasive blood flow measurement by this system is feasible. The results also suggest that this approach can provide blood flow information throughout the whole depth profile of the tissue.


Assuntos
Velocidade do Fluxo Sanguíneo , Fluxo Sanguíneo Regional , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise Espectral/métodos , Humanos , Análise Espectral/instrumentação
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(9): 2519-22, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23240430

RESUMO

A novel strategy by means of poly diallyl dimethylammonium chloride (PDDA) was used to make highly mono-dispersed positively charged gold nanoparticles, and 5-ALA was immobilized onto the gold nanoparticles through electrostatic interaction. The conjugation of 5-aminolevulinic acid (5-ALA) and gold nanopartilces were characterized by the integrated tools of resonance Rayleigh scattering (RRS), UV-Vis absorption spectra, transmission electron microscopy (TEM) and laser light scattering. The results demonstrated that 5-ALA can be attached onto positively charged gold nanoparticles. This new photosensitizer is significant for enhancing PDT efficacy clinically.


Assuntos
Ácido Aminolevulínico/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Ouro , Luz , Nanopartículas Metálicas , Microscopia Eletrônica de Transmissão , Eletricidade Estática
6.
Arch Virol ; 155(5): 657-63, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20229117

RESUMO

The purpose of our study was to investigate the expression of prostate stem cell antigen (PSCA), piwi-like 1 (PIWIL1) and T-box 2 (TBX2) and its correlation with HPV16 infection in cervical squamous cell carcinoma (CSCC). HPV16 was detected by amplifying the HPV16 E7 gene by the polymerase chain reaction (PCR) method, and the expression of PSCA, PIWIL1, TBX2 and HPV16 E7 in 59 CSCCs and matched adjacent normal cervix (MANC) was examined by the streptavidin-peroxidase (SP) method. Fifty-two CSCCs and MANC specimens that were positive for the E7 gene and the E7 protein were identified as infected with HPV16 and included in present study. The rate of infection with HPV16 in CSCC was 52% (27/52), but that in matched adjacent normal cervix (MANC) samples was 4% (2/52). Infection with HPV16 was found to be statistically more frequent in CSCC (P = 0.000). The expression rates of PSCA, PIWIL1 and TBX2 in MANC were 6% (3/52), 8% (4/52) and 2% (1/52), respectively, but those in CSCC were 62% (32/52), 75% (39/52) and 52% (27/52), respectively. Higher expression rates of PSCA, PIWIL1 and TBX2 were observed in CSCC than in MANC (P = 0.000). HPV16 had a statistical positive correlation with PSCA, PIWIL1 and TBX2 in CSCC (P < 0.05). The increased expression of PSCA, PIWIL1 and TBX2 had no correlation with the patient's age or histological grade P > 0.05). The elevated expression of PSCA and PIWIL1 was associated with invasion of CSCC (P < 0.05). Up-regulated expression of TBX2 had a positive association with lymph node metastasis (P = 0.014). These findings demonstrate for the first time the expression of PSCA, PIWIL1 and TBX2 in CSCC. Their correlation with HPV16 might provide new basic information for investigating the molecular mechanism of HPV and help us to deepen our understanding of the interaction between HPV16 and host cells the carcinogenesis of CSCC.


Assuntos
Carcinoma de Células Escamosas/etiologia , Glicoproteínas de Membrana/análise , Proteínas de Neoplasias/análise , Proteínas E7 de Papillomavirus/análise , Proteínas/análise , Proteínas com Domínio T/análise , Neoplasias do Colo do Útero/etiologia , Antígenos de Neoplasias , Proteínas Argonautas , Carcinoma de Células Escamosas/virologia , Feminino , Formaldeído , Proteínas Ligadas por GPI , Humanos , Imuno-Histoquímica , Proteínas E7 de Papillomavirus/genética , Inclusão em Parafina , Neoplasias do Colo do Útero/virologia
7.
Onkologie ; 33(5): 241-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20502058

RESUMO

BACKGROUND: Endometrial cancer is the 4th most common gynecological cancer. The expression of prostate stem cell antigen (PSCA), piwi-like 1 (PIWIL1), and T-box 2 (TBX2) in endometrial cancer remains to be elucidated. MATERIAL AND METHODS: The expression of PSCA, PIWIL1, and TBX2 was examined using the streptavidin-peroxidase method in 64 endometrial endometrioid adenocarcinoma (EAC) and paired normal endometrium (NE) samples from the Shaanxi Province in China. RESULTS: Positive expression rates of PSCA, PIWIL1, and TBX2 were 75% (48/64), 25% (16/64), and 56% (36/64), respectively in EACs, but 5% (3/64), 6% (4/64), and 2% (1/64), respectively in NEs. The difference was statistically significant (p < 0.05). PSCA was positively correlated with TBX2 (p = 0.003) but not PIWIL1 (p = 0.188). PIWIL1 was positively correlated with TBX2 (p = 0.003). PSCA was positively correlated with age, tumor grade, and lymph node metastasis (p < 0.05). TBX2 had an association with lymph node metastasis (p = 0.014). PIWIL1 was not associated with clinicopathological features (p > 0.05). CONCLUSIONS: We report the first analysis of PSCA, PIWIL1, and TBX2 expression in EAC. Our findings suggest that PSCA and TBX2 might be candidate targets for cancer therapy, and have helped us further understand the carcinogenesis of endometrial cancer.


Assuntos
Adenocarcinoma/genética , Neoplasias do Endométrio/genética , Regulação Neoplásica da Expressão Gênica/genética , Glicoproteínas de Membrana/genética , Proteínas de Neoplasias/genética , Proteínas/genética , Proteínas com Domínio T/genética , Adenocarcinoma/patologia , Adulto , Fatores Etários , Idoso , Antígenos de Neoplasias , Proteínas Argonautas , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Neoplasias do Endométrio/patologia , Endométrio/patologia , Feminino , Proteínas Ligadas por GPI , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática/patologia , Pessoa de Meia-Idade
8.
Onkologie ; 33(10): 500-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20926896

RESUMO

BACKGROUND: Apoptosis-stimulating protein of p53 (ASPP) family members can stimulate the apoptotic function of p53 but have no impact on its cell cycle arrest function. MATERIAL AND METHODS: The expression pattern of the ASPP family consisting of ASPP1, ASPP2, and iASPP was examined by immunohistochemistry in 45 formalin-fixed and paraffin-embedded endometrial endometrioid adenocarcinoma (EEA) specimens and 26 normal endometrial tissue (NET) samples. RESULTS: The expression rates of ASPP1 and ASPP2 in EEA were significantly lower than those in NET (p < 0.05). However, the iASPP expression rate in EEA was statistically higher in contrast to NET (p < 0.05). Expression of ASPP1 and iASPP in EEA had no correlation with any clinicopathological features (p > 0.05). iASPP was associated with grade, invasion, and lymph node metastasis (p < 0.05). CONCLUSIONS: It is a novel finding that the expression pattern of the ASPP family members has respective pathological and clinical implications in EEA, and iASPP might be a candidate target for EEA therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Repressoras/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo
9.
Gen Physiol Biophys ; 29(1): 12-22, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20371876

RESUMO

Ventricular arrhythmias are commonly observed in patients with ischemia. It is reported that the electrophysiological changes evoked by ischemia are greater in the epicardium than in the endocardium. To investigate the effects of this heterogeneity on transmural reentry, the computer simulation method is used. A two-dimensional model which can reproduce the endocardial, epicardial and middle cell types, approximate the ischemic characteristics and distribution of the ischemic severity is developed by setting different ratios of the maximum conductance of the rapid and slow inward rectifier potassium currents and considering the three major component conditions of acute ischemia at the ionic level. The results demonstrate that action potentials of the ischemic cells have elevated resting potential, shortened duration, slowed upstroke and declined amplitude. Conduction velocity is much more depressed in the epicardium because of the ischemia-induced transmural gradient of excitability. The epicardially initiated activation has wider vulnerable window and more possibility to cause unidirectional propagation even reentry. Dispersion of the excitability is proposed to be the underlying mechanism.


Assuntos
Arritmias Cardíacas/complicações , Arritmias Cardíacas/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Isquemia/complicações , Isquemia/fisiopatologia , Modelos Cardiovasculares , Miócitos Cardíacos/metabolismo , Animais , Simulação por Computador , Humanos
10.
Bioresour Technol ; 309: 123370, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32311658

RESUMO

1-Hydroxy-3,6-dioxabicyclo[3.2.1]octan-2-one (LAC) is a valuable chiral compound, which can be prepared from catalytic fast pyrolysis (CFP) of cellulose. In this study, nitrided HZSM-5 (N-HZSM-5) and metal-loaded N-HZSM-5 were prepared for CFP of cellulose to selectively produce LAC. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and lab-scale experiments were conducted to explore LAC preparation affected by nitridation and metal modification of HZSM-5, pyrolytic reaction temperature and catalyst-to-cellulose (CA/CL) ratio. The Py-GC/MS experiments obtained the maximal LAC yield of 7.48 wt% with the corresponding selectivity of 30.33% under 5 wt% Mg loaded N-HZSM-5 (5%Mg/N-HZSM-5) with the CA/CL ratio of 6 at 350 °C, compared with those of 1.22 wt% and 2.87% in non-catalytic process. Moreover, lab-scale experiments resulted in the LAC yield and selectivity of 6.69 wt% and 26.18% under the conditions of 5%Mg/N-HZSM-5, CA/CL ratio of 4 and 400 °C. The results demonstrated the promising catalytic performance of Mg/N-HZSM-5 on LAC production from CFP of cellulose.


Assuntos
Celulose , Pirólise , Catálise , Temperatura Alta , Metais
11.
J Int Med Res ; 48(8): 300060520945885, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32809884

RESUMO

OBJECTIVE: The prevalence of overweight/obesity in China has increased dramatically in recent years; being overweight/obese can increase the risk of type 2 diabetes and cardiovascular disease. The purpose of this study was to determine the population in China at high risk of being overweight or obese, to explore the relationships between various relevant factors and overweight/obesity, and to identify preventive efforts for high-risk populations. METHODS: We administered a questionnaire survey among a group of 536 social workers in Shijiazhuang City in 2017. We used the Pearson chi-square test, Spearman's rho test, multivariate linear regression, univariate and multivariate logistic regression, and receiver operating characteristic curve analysis to investigate factors that influence overweight/obesity. RESULTS: The prevalence of overweight/obesity was 13.7% among the study participants. Urban residence, eating speed, number of daily meals, overeating, and a high-fat diet were associated with overweight/obesity. In multivariate linear regression analysis, overweight/obesity was correlated with sex, urban residence, eating speed, number of daily meals, and a high-fat diet. CONCLUSION: Among all influencing factors, dietary factors, place of residence, and sex were most closely related to being overweight/obese. Furthermore, living in an urban area and male sex were independent risk factors for being overweight/obese.


Assuntos
Diabetes Mellitus Tipo 2 , Povo Asiático , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Humanos , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Prevalência , Fatores de Risco , População Urbana
12.
Onkologie ; 32(10): 574-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19816074

RESUMO

BACKGROUND: Esophageal cancer is the fourth most prevalent malignancy in China. The relationship between COX-2, CD44v6, and nm23H1 in esophageal squamous cell carcinoma (ESCC) remains unclear. MATERIAL AND METHODS: Expression of COX-2, CD44v6, and nm23H1 was examined, using the streptavidin-peroxidase method, in 82 ESCC and 30 normal esophageal mucosa (NEM) samples from the Shaanxi Province in China. RESULTS: The positive rates of COX-2, CD44v6, and nm23H1 were 73.2% (60/82), 64.6% (53/82), and 24.4% (31/82), respectively in ESCC, but 6.7% (2/30), 3.3% (1/30), and 90% (27/30), respectively in NEMs. There was a statistically significant difference between NEMs and ESCCs (p < 0.05). Expression of COX-2 showed a positive statistical correlation with expression of CD44v6 (r = 0.4732, p < 0.0001), and an inverse correlation with nm23H1 (r = -0.3226, p = 0.0035). Expression of COX-2, CD44v6, and nm23H1 had no significant correlation with gender or age (p > 0.05), but increased expression of COX-2 and CD44v6 showed statistical correlation with invasion and lymph node metastasis, respectively (p < 0.05). Decreased expression of nm23H1 was statistically correlated with lymph node metastasis (p = 0.0007) but had no correlation with invasion (p = 0.8221). CONCLUSIONS: This is the first report of a significant correlation between COX-2, CD44v6, and nm23H1 in ESCC. This knowledge might help us to further understand the molecular mechanisms of carcinogenesis and progression of ESCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/metabolismo , Ciclo-Oxigenase 2/análise , Neoplasias Esofágicas/metabolismo , Receptores de Hialuronatos/análise , Nucleosídeo NM23 Difosfato Quinases/análise , Proteínas de Neoplasias/análise , Carcinoma de Células Escamosas/epidemiologia , China/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(6): 1651-5, 2009 Jun.
Artigo em Zh | MEDLINE | ID: mdl-19810552

RESUMO

The present study investigated the three-dimensional spectra and emission spectra of the autofluorescence of rabbit hearts. The results suggested that the three-dimensional spectra of the iced atria and ventricle were observed more evidently different from that of the fresh tissue compared to the main artery, which indicated that the amount of flavins and NADHs changed. Also, the atria, ventricle and main artery have different specific excitation spectra at the wavelength of 340 nm. The main fluorescence peaks were of NADH (at about 460 nm), collagen and elastin (at about 290-400 nm). The Gauss spectra of atria and ventricle were different in the peak value, relative intensity and half width. So the ratios of fluorescence intensities of peaks may be used to distinguish different heart tissues. Furthermore, a phenomenon was firstly uncovered that the autofluorescence intensity of NADH in ventricle decays with the time of death and it could be a useful method for the estimation of postmortem interval.


Assuntos
Miocárdio/citologia , Animais , Morte Celular , Flavinas/metabolismo , Átrios do Coração/citologia , Átrios do Coração/metabolismo , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Miocárdio/metabolismo , NAD/metabolismo , Coelhos , Espectrometria de Fluorescência , Temperatura , Fatores de Tempo
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(5): 1331-5, 2009 May.
Artigo em Zh | MEDLINE | ID: mdl-19650483

RESUMO

The laser-inducted fluorescence spectrum technology (LIF) was used for the first time to study the autofluorescence spectral characteristics of the heart, kidney, liver, fat, foreleg muscle, hind leg soleus muscle and musculus gastrocnemius of the rat performing motion exercises. The wavelength of the excitation light used during the measurement was in the range of 250-650 nm and the emission wavelength was 300-700 nm. When comparing the three-dimensional fluorescence spectra of the control group with those of the four groups of different motion states, a specific fluorescence peak related to the motion and located in the area where the excitation wavelength was (340 +/- 10) nm and the emission wavelength was (460 +/- 10) nm was found mainly in the spectra of the soleus muscle. From this fluorescence peak, it is possible to determine that its corresponding fluorescent substance is NADH (nicotinamide adenine dinucleotide reduced). When comparing the fluorescence spectra of the four groups of different motion modes, it was found that the motion mode has a conspicuous relativity with the peak intensity. The results show that the energy metabolism of the soleus muscle of the rat in motion is stronger than that of the foreleg, soleus muscle and other visceras, and the autofluorescence spectral characteristics of NADH form one of the effective indexes for determining the muscular metabolism degree.


Assuntos
Condicionamento Físico Animal/fisiologia , Animais , Lasers , Masculino , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Ratos , Ratos Sprague-Dawley , Espectrometria de Fluorescência
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(3): 617-20, 2008 Mar.
Artigo em Zh | MEDLINE | ID: mdl-18536426

RESUMO

Recently, non-invasive optical methods to monitor transmembrane electrical potential using voltage sensitive dyes have been applied widely in the studies of normal and pathological heart rhythms and defibrillation. In the present paper, the authors measured the excitation and the emission spectra of the voltage-sensitive dyes di-4-ANEPPS bound to phospholipid bilayer membranes. And according to the spectral shift of di-4-ANEPPS, the authors presented an optical mapping system combining a DALSA CCD camera and a LED light source. Using this optical mapping system, the authors could record the action potential duration of the heart cells with high spatial and temporal resolutions. It can be a powerful tool in the study of cardiac arrhythmia mechanisms.


Assuntos
Corantes Fluorescentes/análise , Compostos de Piridínio/análise , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Animais , Corantes Fluorescentes/química , Bicamadas Lipídicas/química , Estrutura Molecular , Miocárdio/química , Compostos de Piridínio/química , Coelhos
16.
Front Chem ; 6: 32, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29515994

RESUMO

A new technique was proposed to co-produce phenol and activated carbon (AC) from catalytic fast pyrolysis of biomass impregnated with K3PO4 in a hydrogen atmosphere, followed by activation of the pyrolytic solid residues. Lab-scale catalytic fast pyrolysis experiments were performed to quantitatively determine the pyrolytic product distribution, as well as to investigate the effects of several factors on the phenol production, including pyrolysis atmosphere, catalyst type, biomass type, catalytic pyrolysis temperature, and catalyst impregnation content. In addition, the pyrolytic solid residues were activated to prepare ACs with high specific surface areas. The results indicated that phenol could be obtained due to the synergistic effects of K3PO4 and hydrogen atmosphere, with the yield and selectivity reaching 5.3 wt% and 17.8% from catalytic fast pyrolysis of poplar wood with 8 wt% K3PO4 at 550°C in a hydrogen atmosphere. This technique was adaptable to different woody materials for phenol production. Moreover, gas product generated from the pyrolysis process was feasible to be recycled to provide the hydrogen atmosphere, instead of extra hydrogen supply. In addition, the pyrolytic solid residue was suitable for AC preparation, using CO2 activation method, the specific surface area was as high as 1,605 m2/g.

17.
Sci Total Environ ; 634: 141-149, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29627536

RESUMO

A series of Mo2N/HZSM-5 and transition metal modified Mo2N/HZSM-5 catalysts were prepared for the catalytic upgrading of pine wood-derived pyrolytic vapors for the selective production of monocyclic aromatic hydrocarbons (MAHs), while restraining the formation of polycyclic aromatic hydrocarbons (PAHs). Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments were performed to determine the effects of several factors on selective MAHs production, including Mo2N loading on HZSM-5, transition metal (Fe, Ce, La, Cu, Cr) modification of Mo2N/HZSM-5, pyrolysis temperature, and catalyst-to-biomass ratio. In addition, quantitative experiments were conducted to determine the actual yields of major aromatic hydrocarbons and the source of aromatic hydrocarbons from basic biomass components. Results indicated that among the various catalysts, the Ce-10%Mo2N/HZSM-5 exhibited the best performance on promoting the formation of MAHs and restraining the generation of PAHs. Under the optimal conditions, the actual yields of MAHs and PAHs from Ce-10%Mo2N/HZSM-5 catalytic process were 99.8mg/g and 7.5mg/g, while those from HZSM catalyst were only 77.2mg/g and 23.7mg/g respectively. Furthermore, the possible catalytic mechanism of the Ce-Mo2N/HZSM-5 catalyst was proposed based on the catalyst characterization.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(7): 1359-62, 2007 Jul.
Artigo em Zh | MEDLINE | ID: mdl-17944414

RESUMO

This study investigated the absorption spectrum and the fluorescence spectrum of rabbit hearts stained with the voltage sensitive dye (di-4-ANEPPS). The results suggested that the optical absorption of tissue with the dye was higher than that of the control group, and there were significant differences between the experimental group and control group in the range of 450-550 nm. It was also indicated that the maximum absorption peak of the dye in tissues was at (479.25 +/- 0.44) nm. Additionally, the different peaks of fluorescence emission spectra from the atriums, ventricles and aorta were originally found by testing the five parts of rabbit hearts with the dye. Their relative intensities were related to the distribution concentrations of the dye. Meanwhile, the peaks of excitation spectra and fluorescence emission spectra were determined by examining the three-dimensional and two-dimensional fluorescence spectra using ventricles and atriums with the dye. Based on the discrepancy of rest membrane voltages between ventricles and atriums, the best wavelength ranges of excitation light and emissions light of optical mapping were determined by the shifts of the dye in emission spectra with excitation at different wavelengths. These results offer a theoretical foundation for the design of a cardiac optical mapping system.


Assuntos
Miocárdio/química , Compostos de Piridínio/química , Espectrometria de Fluorescência/métodos , Espectrofotometria/métodos , Animais , Vasos Coronários/química , Vasos Coronários/fisiologia , Estimulação Elétrica , Corantes Fluorescentes/química , Coração/fisiologia , Átrios do Coração/química , Ventrículos do Coração/química , Técnicas In Vitro , Potenciais da Membrana , Coelhos
19.
Math Biosci ; 203(1): 1-18, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16904128

RESUMO

The underlying ionic mechanisms of ischemic-induced arrhythmia were studied by the computer simulation method. To approximate the real situation, ischemic cells were simulated by considering the three major component conditions of acute ischemia (elevated extracellular K(+) concentration, acidosis and anoxia) at the level of ionic currents and ionic concentrations, and a round ischemic zone was introduced into a homogeneous healthy sheet to avoid sharp angle of the ischemic tissue. The constructed models were solved using the operator splitting and adaptive time step methods, and the perturbation finite difference (PFD) scheme was first used to integrate the partial differential equations (PDEs) in the model. The numerical experiments showed that the action potential durations (APDs) of ischemic cells did not exhibited rate adaptation characteristic, resulting in flattening of the APD restitution curve. With reduction of sodium channel availability and long recovery of excitability, refractory period of the ischemic tissue was significantly prolonged, and could no longer be considered as same as APD. Slope of the conduction velocity (CV) restitution curve increased both in normal and ischemic region when pacing cycle length (PCL) was short, and refractory period dispersion increased with shortening of PCL as well. Therefore, dynamic changes of CV and dispersion of refractory period rather than APD were suggested to be the fundamental mechanisms of arrhythmia in regional ischemic myocardium.


Assuntos
Modelos Cardiovasculares , Isquemia Miocárdica/fisiopatologia , Fibrilação Ventricular/etiologia , Acidose/fisiopatologia , Potenciais de Ação/fisiologia , Simulação por Computador , Humanos , Hipóxia/fisiopatologia , Potássio/fisiologia , Fibrilação Ventricular/fisiopatologia
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(9): 1668-71, 2006 Sep.
Artigo em Zh | MEDLINE | ID: mdl-17112043

RESUMO

The interaction of aclacinomycin(ACR) and DNA was investigated by fluorescence spectrum, and the characteristics of the fluorescence and absorption of aclacinomycin (ACR) were studied. The results indicate that there are two situations: in the case that the concentration ratio of ACR to DNA is small, the ACR is intercalated into the stacked base pairs of DNA; in the other case that the concentration ratio of ACR to DNA is great, the interaction between ACR and DNA is complex. The binding constant of the interaction between ACR and DNA, calculated by the fluorescence titration method, is 2.7 x 10(6) mol x L(-1), and the binding site number is about 0.67 base pairs.


Assuntos
Aclarubicina/análogos & derivados , DNA/química , Espectrometria de Fluorescência , Aclarubicina/química , Animais , Bovinos , Etídio/análogos & derivados , Etídio/química , Fluorescência , Concentração de Íons de Hidrogênio , Estrutura Molecular
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