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Eu³âº doped BaSrMg (PO4)2 were prepared by a hydrothermal method. The crystal structure and morphology of BaSrMg(PO4)2:Eu³âº phosphor were characterized by X-ray powder diffraction (XRD) and field emission scanning electron microscopy (FESEM). The effects of different pH values (5, 6, 7 and 8) and different reaction temperatures (120, 140, 160, 180 and 200 °C) on the crystal structure and morphology of BaSrMg(PO4)2:Eu³âº phosphor were studied in this paper. The results of XRD indicate that diffraction peaks are sharp and strong only when pH value is 6, meanwhile the FESEM shows the morphology is regular-shaped. The XRD patterns show amorphous halos superimposed with several weak sharp peaks for the samples preparing under the pH values of 5, 7 and 8. It indicates that these three samples are solid solution or mixed phases, which are in accord with the results of FESEM. From the fluorescence spectra, the peaks in the excitation spectra were assigned to the transition from 7F0 to 5D4, 5L8, 5L6 and 5D2, while the peaks of emission spectra corresponding to the transition of 5D1 --> 7F1 and 5D0-->7Fj (J = 0, 1, 2, 3 and 4). The strongest emission peak of the optimized phosphor located at 613 nm (5D0--> 7F2), excited by the main excitation peak with wavelength of 394 nm. The splitting of the emission peaks changes depends on pH values and temperatures, which indicating that luminescence properties is closely related to the crystal structure and morphology of particles.
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The magnetic Fe3O4/Ag composite materials were synthesized by reducing AgNO3 with sodium citrate in the presence of Fe3O4 which were prepared by co-precipitation firstly. The enrichment and extraction of ethoprophos assembled on Fe3O4/Ag were achieved with the applied magnetic field. The different concentrations of ethoprophos adsorbed on Fe3O4/Ag were analyzed by SERS and it was showed that the trace analysis of ethoprophos had been established, while the enhancement factor of probe molecules on Fe3O4/Ag was 1. 48 X 10(5). The structure and morphology of Fe3O4/Ag were characterized by UV-Vis, EDX and TEM. Compared with Ag, the UV-Vis absorption peak of Fe3O4/Ag shifted from 417 to 369 nm, and the UV-Vis of Fe3O4 almost had no characteristic absorption peak in this region. At the same time, it was showed that the surface properties of Fe3O4/Ag changed with Raman enhancement effect during the aggregation process of Ag around the surface of Fe3O4. Further EDX images of micro area element analysis suggested that the chemical composition of products were Ag, Fe and O while the Cu peak was from the copper mesh. In addition, TEM images indicated that the average particle size of Fe3O4 was between 30 and 60 nm with shape tended to be spherical. And the silver nanoparticles were attached to the Fe3O4 particles and agglomeration occured. Density functional theory calculations which can be applied to qualitative judgment of molecule was carried out to obtain the molecular optimization structure and theoretical Raman spectra. It was found that the stabilized SERS signals were detected under the saturated adsorption equilibrium after 15 min. Finally, Raman response of ethoprophos was achieved with lower than 2 X 10(-8) mol . L-1 , indicatint that the established method had reached the requirements of ethoprophos residues detection and could be used for analysis of sulfur-containing organophosphorus pesticide.
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2,3-Dimercaptosuccinic acid (DMSA) and its complex Nickel(II) 2,3-Dimercaptosuccinate (DMSA-Ni(II)) were assembled on the electrochemically activated Au electrode and the modified films were investigated by ex-situ SERS, SEM and electro-reduction. The coordination ratio (1:2) and stability constant (4.716 X 10(7)) of DMSA and Nickel(II) were firstly confirmed by UV. Then, the SERS spectra showed that DMSA was absorbed on the surface of activated Au and the coordinate bond of DMSA-Ni(II) was existed as S-Ni-O. Meanwhile, two reduction peaks of DMSA-Ni(II) on Au electrode were presented at negative potential. The first peak (from positive to negative values) was related to the RS-Au group which was produced by the mutual absorption of DMSA and Au. The second reduction peak was related to Nickel(II). Finally, it was further confirmed by calculating the surface coverage and comparison of molecular area. And it was found that the molecular arrangement of DM-SA-Ni(II) on Au electrode generated as monolayer which was dispersed or connected partly instead of concentrated or overlapped.
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Surface-enhanced Raman scattering (SERS) of thiosalicylic acid (TSA) with sulfydryl group was investigated on the surface of electrochemically roughed silver electrode. The result shows that SERS enhancement effect was relative to the concentration and pH, and 1 x 10(-3) mol x L(-1) and pH 4 were the optimal condition. While the concentration increased, the enhancement effect decreased quickly because of steric hindrance. S--Ag peak position by the absorption of TSA was basically consistent, but pH significantly affected its intensity. The distribution and mechanism of TSA at different pH were further investigated. It was showed that TSA was adsorbed on the active silver surface via the sulfydryl group without H of neutral C4H4 (COOH)SH molecule. Competitive adsorption of negative valence C4H4 (COO-) SH and OH- may bring non-SERS under the strong base condition. At the same time, the sulfydryl group significantly influenced the carboxyl vibration peak's change and the distribution of electron cloud of benzene ring conjugate system.
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OBJECTIVE: To investigate the effects of Pien Tze Huang (PZH) on the migration and invasion of HCC cells and underlying molecular mechanism. METHODS: Cell counting kit-8 (CCK-8) was applied to evaluate the cell viabilities of SMMC-7721, SK-Hep-1, C3A and HL-7702 (6 × 103 cells/well) co-incubated with different concentrations of PZH (0, 0.2, 0.4, 0.6, 0.8 mg/mL) for 24 h. Transwell, wound healing assay, CCK-8 and Annexin V-FITC/PI staining were conducted to investigate the effects of PZH on the migration, invasion, proliferation and apoptosis of SK-Hep-1 and SMMC-7721 cells (650 µ g/mL for SK-Hep-1 cells and 330 µ g/mL for SMMC-7721 cells), respectively. In vivo, lung metastasis mouse model constructed by tail vein injection of HCC cells was used for evaluating the anti-metastasis function of PZH. SK-Hep-1 cells (106 cells/200 µ L per mice) were injected into B-NDG mice via tail vein. Totally 8 mice were randomly divided into PZH and control groups, 4 mice in each group. After 2-d inoculation, mice in the PZH group were administered with PZH (250 mg/kg, daily) and mice in the control group received only vehicle (PBS) from the 2nd day after xenograft to day 17. Transcriptome analysis based on RNA-seq was subsequently used for deciphering anti-tumor mechanism of PZH. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were applied to verify RNA-seq results. Luciferase reporter assay was performed to examine the transcriptional activity of yes-associated protein (YAP). RESULTS: PZH treatment significantly inhibited the migration, invasion, proliferation and promoted the apoptosis of HCC cells in vitro and in vivo (P<0.01). Transcriptome analysis indicated that Hippo signaling pathway was associated with anti-metastasis function of PZH. Mechanical study showed PZH significantly inhibited the expressions of platelet derived growth factor receptor beta (PDGFRB), YAP, connective tissue growth factor (CCN2), N-cadherin, vimentin and matrix metallopeptidase 2 (MMP2, P<0.01). Meanwhile, the phosphorylation of YAP was also enhanced by PZH treatment in vitro and in vivo. Furthermore, PZH played roles in inhibiting the transcriptional activity of YAP. CONCLUSION: PZH restrained migration, invasion and epithelial-mesenchymal transition of HCC cells through repressing PDGFRB/YAP/CCN2 axis.
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A single-host white-light-emitting phosphor BaSrMg(PO4)2 : EU2+ was prepared by high temperature solid-state reaction method, and the luminescence characteristics and XRD pattern were investigated. The results showthat BaSrMg(PO4)2 phase was obtained by sintering at 1 200 degrees C for 3 hours. BaSrMg(PO4)2 = Eu2+ phosphor exhibits two main emission bands peaking at 424 and 585 nm, respectively. The emission band peaking at 424 nm is attributed to the 4f 6 5d1 --> 4f7 transition of Eu2+ substituting Sr2+, while the emission band peaking at 585 nm originates from the 4f 6 5d1 --> 4f7 transition of Eu2+ replacing Ba2+ in host lattice. The excitation spectra of the two emission peaks are range from 250 to 400 nm and both peaking at 360 nm. The effect of the proportion of Ba and Sr, and the Eu2+ doping concentration on the emission intensity were discussed in detail. Different chromaticity coordinates were obtained for each phosphor, that is, the chromaticity coordinates of the designed phosphor is tunable for the white-emitting LED or for special purpose. Quantum efficiency was also examined for the phosphors with different Eu2+ doping concentration, and concentration quenching took place obviously when Eu2+ doping concentration was lager than 6% in mole ratio. The obtained phosphor BaSrMg(PO4)2 : Eu2+ can be excited by near ultraviolet radiation effectively and emit full color lighting, which is a promising single-host white-light-emitting phosphor for white LED.
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BACKGROUND: The robotic technique has been established as an alternative approach to laparoscopy for colorectal surgery. The aim of this study was to compare the short-term outcomes of robot-assisted and laparoscopic surgery in colorectal cancer. METHODS: The cases of robot-assisted or laparoscopic colorectal resection were collected retrospectively between July 2015 and September 2018. We evaluated patient demographics, perioperative characteristics, and pathologic examinations. Short-term outcomes included time to passage of flatus and length of postoperative hospital stay. RESULTS: A total of 580 patients were included in the study. There were 271 patients in the robotic colorectal surgery (RCS) group and 309 in the laparoscopic colorectal surgery (LCS) group. The time to passage of flatus in the RCS group was 3.62 days shorter than the LCS group. The total costs were increased by 2,258.8 USD in the RCS group compared to the LCS group (P < 0.001). CONCLUSION: The present study suggests that colorectal cancer robotic surgery was more beneficial to patients because of a shorter postoperative recovery time of bowel function and shorter hospital stays.
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Neoplasias Colorretais/mortalidade , Cirurgia Colorretal/mortalidade , Laparoscopia/mortalidade , Procedimentos Cirúrgicos Robóticos/mortalidade , Idoso , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
The aim of this study was to evaluate and compare the intestinal function recovery time and other short-term outcomes between robotic-assisted total mesorectal excision (R-TME) and laparoscopic total mesorectal excision (L-TME) for rectal cancer. This is a retrospective study using a prospectively collected database. Patients' records were obtained from Gansu Provincial Hospital between July 2015 and October 2017. Eighty patients underwent R-TME, and 116 with the same histopathological stage of the tumor underwent an L-TME. Both operations were performed by the same surgeon, comparing intra- and postoperative outcomes intergroups. The time to the first passage of flatus (P < 0.001), the time to the first postoperative oral fluid intake (P < 0.001), and the length of hospital stay (P < 0.01) of the R-TME group were about three days faster than those in the L-TME group. The rate of conversion to open laparotomy (P = 0.038) and postoperative urinary retention (P = 0.016) were significantly lower in the R-TME group than in the L-TME group. Intraoperative blood loss of the R-TME group was more than that of the L-TME group (P < 0.01).The operation time, number of lymph nodes harvested, and rate of positive circumferential resection margin were similar intergroup. The total cost of the R-TME group was higher than that of the L-TME group, but with a lack of statistical significance (85,623.91 ± 13,310.50 vs 67,356.79 ± 17,107.68 CNY, P = 0.084). The R-TME is safe and effective and has better postoperative short-term outcomes and faster intestinal function recovery time, contrasting with the L-TME. The large, multicenter, prospective studies were needed to validate the advantages of robotic surgery system used in rectal cancer.
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Adenocarcinoma/cirurgia , Laparoscopia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Robóticos , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Duração da Cirurgia , Recuperação de Função Fisiológica , Neoplasias Retais/patologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
The surface enhanced Raman scattering (SERS) of L-phenylalanine solution system was studied in the present paper. The enhancement effect is obvious. Compared to the conventional Raman spectra of solid phenylalanine, the frequency deviations of some peaks in the SERS spectra were observed, and the relative strengths of some peaks were certainly changed. The influence of three different laser sources on the intensity of SERS spectra is discussed. The 514.42 nm of laser source is the best among the 514.42, 632.81 and 785.18 nm. The intensity of SERS spectra can be changed with the concentration of L-phenylalanine. It does not benefit the formation of SERS spectra when the concentration is too high or too low. When the concentration of bottom solution is 1 x 10(-3) mol x L(-1), the enhancement effect of SERS is the strongest. The pH value of system also has obvious effect on the SERS, and when the pH value is 8, the enhancement effect of SERS is the best. It is the total influence of the pH on the coacervation of the silver sol and existent form of the phenylalanine.
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Fenilalanina/análise , Prata/química , Análise Espectral Raman/métodos , Concentração de Íons de HidrogênioRESUMO
Cystine was indirectly determined by flame atomic absorption spectrometry with ZnS. Base on the determination mechanism, the composition of complex, the complex balance reaction of soluble zinc ion, which formed in the determination of cystine by FAAS, and the stability constant of complex balance were discussed in the present paper. Under the alkalescent conditions, cystine (Cys-Cys) can react with zinc sulfide suspension solution to form a soluble complex or chelate of zinc cystine. The maximum concentration was reached at pH 9.4 and the quantity of the chelate was determined by flame atomic absorption spectrometry with zinc sulfide. The stability constants of the complex compound of zinc cystine were studied successfully, after the numeric measurements and theoretical investigations under the best-optimized acidity for determination. In conclusion, at the best optimized acidity pH 9.4, the stability constant of alkalescent zinc cystine is between 9. 542 x 10(32) and 10.353 x 10(32), the average value is betaw = 9.916 x 10(32), and log betaw = 32.996. The standard deviation is 0.301 x 10(32). It is shown that the atomic absorption spectrometry can be used not only for the determination of trace elements and the indirect determination of organic compound, but also for the study of physical configuration and the determination of physical constant of complex ion.
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Quelantes/análise , Cistina/análise , Espectrofotometria Atômica/métodos , Sulfetos/química , Compostos de Zinco/química , Zinco/análise , Concentração de Íons de Hidrogênio , Estrutura MolecularRESUMO
Each state of cystine and zinc ion in aqueous solution under different pH conditions was calculated by computer, and the scatter diagram was given. Under the influence of solution pH, the mechanism of complex reaction in indirectly determining cystine by flame atomic absorption spectrometry with ZnS was studied. The soluble complex ion is composed of 0 valence cystine Cys-Cys+/-, -1 valence cystine Cys-Cys+/- and -2 valence cystine Cys-Cys(2-) with Zn(OH)2. The theoretical analysis from computing and scatter diagram dovetail very well with the data determined from the experiments. The structure of soluble zinc-cystine complex ion is, [(COO-) CH (NH3+) CH2S-SCH2 CH (NH3+) COO-] Zn (OH)2, [(COO-) CH (NH3+) CH2S-SCH2CH(NH2)COO-]Zn(OH)2 and [(COO-)CH(NH2)CH2S-SCH2CH(NH2)COO-]Zn(OH)2.
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INTRODUCTION: Xylazine, a type of α2-adrenoceptors, is a commonly used drug in veterinary medicine. Xylazine-induced changes in the content of amino acid neurotransmitters - glycine (Gly) and aspartic acid (Asp), in different brain regions and neurons were studied. MATERIAL AND METHODS: Wistar rats were administered 50 mg/kg or 70 mg/kg of xylazine by intraperitoneal injection. In addition, in vitro experiments were conducted, in which neurons were treated with 15 µg/mL, 25 µg/mL, 35µg/mL, and 45 µg/mL of xylazine. Test methods were based on the enzyme-linked immunosorbent assays (ELISA). RESULTS: During anaesthesia, Asp levels in each brain area were significantly lower compared to the control group. Except for the cerebrum, levels of Gly in other brain areas were significantly increased during the anaesthesia period. In vitro, xylazine-related neuron secretion of Gly increased significantly compared to the control group at 60 min and 90 min. Moreover, xylazine caused a significant decrease in the levels of Asp secreted by neurons at 20 min, but gradually returned to the level of the control group. CONCLUSION: The data showed that during anaesthesia the overall levels of Asp decreased and overall levels of Gly increased. In addition, the inhibitory effect of xylazine on Asp and the promotion of Gly were dose-dependent. Our data showed that different effects of xylazine on excitatory and inhibitory neurotransmitters provided a theoretical basis for the mechanism of xylazine activity in clinical anaesthesia.
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In the present paper we report quantitative analysis of glucose using internal standard laser Raman spectra. A good linear correlation was observed between the intensities of the -COO band at 1 125 cm(-1) using excition wavelength of 632.81 nm (r = 0.998 8) and the glucose concentration over the range 0-1.8 mol x L(-1). Band intensities were normalized against an internal standard (water band at 1 643 cm(-1)), and the limit of detection (L. O. D.) of glucose is 0.022 7 mol x L(-1). The interference ions would not influence the quantitative analysis. When this method was used to determine 5% glucose NaCl, 5% glucose, and 10% glucose injections, the result showed that the recoveries are 71.88%-126.31%, 81.02%-124.89% and 74.87%-121.32%, and the RSDs are 5.44%, 4.34% and 0.94%, respectively. The non destructive, non intrusive nature of the method makes internal standard laser Raman spectra a convenient, accurate, and green quantitative analysis method.
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Glucose/análise , Análise Espectral Raman/métodos , Glucose/normas , Lasers , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
Twelve kinds of fish tissues were wetly decomposed and the harmful elements of Cd, As, Pb and Hg were determined by ICP-AES method in the present paper. The techniques for operating ICP instrument were optimized, spectral interference for elements in special wavelength range was studied, and the correction factor of IECs model was established. The results indicated that the signal to noise ratio and detection limit for elements with higher ionization potential energy may be improved by increasing the radio generator power properly and reducing the nebulizer pressure. There were Cr, Cu, As, Sn and Na elements that mainly disturbed the determined elements such as As (189.042 nm), Pb (220.353 nm), Cd (228.802 nm) and Hg (184.950 nm). The primary contaminating elements in tissues of freshwater fish and seawater fish were Pb and As respectively.
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Peixes/metabolismo , Água Doce/análise , Espectrofotometria Atômica/métodos , Poluentes Químicos da Água/análise , Animais , Arsênio/análise , Cádmio/análise , Peixes/classificação , Análise de Alimentos/métodos , Água Doce/química , Chumbo/análise , Mercúrio/análise , Especificidade da Espécie , Poluentes Químicos da Água/metabolismoRESUMO
Each state of histidine and zinc ion in aqueous solution with different pH was calculated by computer, producing the scatter diagram. Under the influence of solution pH, the mechanism of complex reaction in indirectly determining histidine by flame atomic absorption spectrometry with ZnS was studied. In different state of histidine and zinc ion in aqueous solution at differential pH, the response peak with pH in giving conditions was obtained. The soluble complex ion is composed of 0 valence histidine His+- and -1 valence histidine His+- and Zn(OH)2. The theoretical analysis from computing and scatter diagram agrees very well with the data determined from the experiments. The structures of complex ion are Zn(OH)2 x (C6N3O2H9)2, H8) Zn(OH)2 x [(C6N3O2H8)-]2 and Zn(OH)2 x (C6N3O2H9) x [(C6N3O2H8)-].
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Many abnormal peaks in laser Raman spectra were found in determinations with laser illuminant of 785. 18 nm. After studies, it was found that the notch filter caused the interferences and the characteristics of the band pass filter were not good. The absorption spectral characteristics of notch filter were studied for the new and old of band pass filters.
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The laser Raman spectra influenced by environmental light were studied in the determination of ZnCl2 solution. The environmental light included the natural light from outdoors and the light from indoor fluorescent. The results show that different influences on the laser Raman spectra of ZnCl2 solution can be produced in different environmental light. There were some characteristic spectral lines, minus peaks or sharpened peaks. These influences cannot be ignored. The determinations of laser Raman spectra must be made in darkroom or in the sheathing or mantle etc.
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The laser Raman spectra influenced by environmental light have been studied in the determination of sodium glutamic acid solution. The environmental light included natural light from outdoors and the light from indoor fluorescents. The results show that different influences on laser Raman spectra of sodium glutamic acid solution can be produced in different environmental light. There were some characteristic spectral lines, minus peaks or sharpened peaks. These influences cannot be ignored. The determinations of laser Raman spectra must be performed in darkroom or in the sheathing or mantle etc.
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The influences of different laser source and different light power on laser Raman spectra were studied for the sodium glutamic acid. The results show that some influences existed using different wavelength and power of light source the peak shifting 6 cm(-1). As UV laser has great light power, the samples were destroyed, making the Raman spectra- reduce or disappear. The attenuation of light was needed. The linear relation existed between the Raman intensity and the power of laser light source, and the correlation coefficient was more then 0.999. The Raman intensity per light power unit was related to the wavelength, and was not related to the power of laser source.
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Glutamato de Sódio/análise , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodosRESUMO
The near-infrared laser Raman spectra influenced by environmental light were studied in the determination of sodium glutamic acid solution. The environmental lights included natural light from outdoors and light from room fluorescent lamp. The results show that different influences on near infrared laser Raman spectra of sodium glutamic acid solution can be produced in different environmental light. There were some characteristic spectral lines, down peaks or sharpened peaks. These influences cannot be ignored. It is suggested that the determination of solution by near-infrared laser Raman spectra is carried out in dark-room or in dark cover to completely isolates the influences of the environment lights.