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1.
Natl Sci Rev ; 8(4): nwaa242, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34691615

RESUMO

The quantum relaxation time of electrons in condensed matters is an important physical property, but its direct measurement has been elusive for a century. Here, we report a breakthrough that allows direct determination of quantum relaxation time at zero and non-zero frequencies using optical measurement. Through dielectric loss function, we connect bound electron effects to the physical parameters of plasma resonance and find an extra term of quantum relaxation time from inelastic scattering between bound electrons and conduction electrons at non-zero frequencies. We demonstrate here that the frequency-dependent inelastic polarization effect of bound electrons is the dominant contribution to quantum relaxation time of conduction electrons at optical frequencies, and the elastic polarization effect of bound electrons also dramatically changes the plasma resonance frequency through effective screening to charge carriers.

2.
Genet Mol Res ; 15(1)2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26909947

RESUMO

The aim of this study was to explore the relationship between adiponectin (ADPN) and hemorrhagic shock (HS) and the recovery after HS. This is significant for further understanding of the pathophysiological processes of HS and the development of better treatments. In total, 72 male C57BL/6 mice were assigned randomly to three groups: control, HS, and recovery (N = 24). The HS mouse model was constructed by hemorrhage of the carotid artery and recovery was achieved by tail vein injection of Ringer's solution. The level of ADPN in the peripheral blood of mice before and after recovery was detected by enzyme-linked immunosorbent assay. Compared to control, HS mice showed significantly decreased ADPN levels with the extension of HS time while the level of ADPN in recovery mice increased significantly and remained high. The variation of ADPN levels was closely associated with the occurrence of HS in mice and their recovery, suggesting that ADPN might act as a biomarker of inflammation and have potential for the treatment of HS.


Assuntos
Adiponectina/sangue , Modelos Animais de Doenças , Inflamação , Recuperação de Função Fisiológica , Choque Hemorrágico/sangue , Adiponectina/imunologia , Animais , Biomarcadores , Artérias Carótidas/metabolismo , Artérias Carótidas/fisiopatologia , Masculino , Camundongos , Choque Hemorrágico/imunologia , Choque Hemorrágico/metabolismo , Choque Hemorrágico/fisiopatologia
3.
J Environ Sci (China) ; 13(3): 276-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11590756

RESUMO

In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2 microns mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2% for silica flour and 67.4% for wood powder smoke. Under the same experimental condition, the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.


Assuntos
Poluentes Atmosféricos/química , Monitoramento Ambiental/instrumentação , Aerossóis , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Desenho de Equipamento , Tamanho da Partícula , Fumaça/análise , Madeira
4.
Hunan Yi Ke Da Xue Xue Bao ; 26(3): 251-3, 2001 Jun 28.
Artigo em Chinês | MEDLINE | ID: mdl-12536697

RESUMO

OBJECTIVES: To explore the influence of zafirlukast on pulmonary functions and quality of life (QOL) in patients with mild-to-moderate asthma at the stage of attack and at the stable stage. METHODS: Patients at the stage of attack were randomly divided into two groups: Group one is zafirlukast 20 mg twice daily plus inhaled the half quantity of glucocorticoid(budelade) of the Global Initiative for Asthma (GINA) standard quantity, long-effection aminophyllin 0.2 g twice daily and inhaled salbutamol when necessary; Group two: inhaled budelade of GINA standard quantity, long-effection aminophyllin 0.2 g twice daily and inhaled salbutamol when necessary). Patients' peak expiratory flow (PEF)/PEF predicted value % and delta PEFR% were determined at the second week and the forth week before and after the treatment. On the standard treatment, patients with the stable stage were added zafirlukast 20 mg twice a day. PEF values in the morning and evening and QOL were evaluated. RESULTS: After treating with zafirlukast, the PEF/PEF predicted value % and delta PEFR% in Group one were higher and lower than those of Group two respevtively. These changes were appeared in two days and were peaked in two weeks and the peak had been gone on for more than 4 weeks, but these were no significant difference between the Groups (P > 0.05); PEF values in the morning and evening in patients with the stable asthma increased 5.9% and 4.6% respectively and their QOL were improved in asthma symptoms, limitative activities, avoiding stimuli, and reacting on stimuli. CONCLUSION: Zafirlukast can improve pulmonary function, reduce the inhalation quantity of steroid in patients with mild-to-moderate asthma, and play an important role in treating and improving QOL in patients with the stable asthma.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Pulmão/fisiopatologia , Qualidade de Vida , Compostos de Tosil/uso terapêutico , Adolescente , Adulto , Asma/fisiopatologia , Feminino , Humanos , Indóis , Masculino , Pessoa de Meia-Idade , Pico do Fluxo Expiratório , Fenilcarbamatos , Testes de Função Respiratória , Sulfonamidas
5.
Hunan Yi Ke Da Xue Xue Bao ; 26(3): 261-2, 2001 Jun 28.
Artigo em Chinês | MEDLINE | ID: mdl-12536700

RESUMO

OBJECTIVE: This paper was to observe the effects of noninvasive positive pressure ventilation (NPPV) on gas exchange and patients' transformation and to evaluate their clinical value. METHODS: Patients were randomly treated by either NPPV, or conventional medicine. The arterial blood gas readings, heart rates (HR), and respiratory rates (HR) were obtained at admission after the treatment. It was necessary to intubate when the clinical deterioation was marked by PaCO2 > 70 mmHg, PaCO2 gradually increasing 5-10 mmHg, pH decreasing 0.05-0.1 or mental obstacle, or PaO2 < 45 mmHg. RESULTS: NPPV significantly decreased the PaCO2 level, HR, and RR, significantly increased the PaO2 level, and also decreased the opportunity of intubation. CONCLUSION: The results suggest that NPPV can improve the gas exchange and reduce the need of intubation in COPD patients with acute respiratory failure.


Assuntos
Respiração com Pressão Positiva , Doença Pulmonar Obstrutiva Crônica/terapia , Troca Gasosa Pulmonar , Insuficiência Respiratória/terapia , Idoso , Gasometria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Insuficiência Respiratória/fisiopatologia
6.
Hunan Yi Ke Da Xue Xue Bao ; 25(1): 53-4, 2000 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-12212248

RESUMO

To study the value of low volume ventilation in chronic obstructive lung disease (COPD) with Type II respiratory failure, 35 patients were divided into two groups at random. The tidal volume of regular volume ventilation group was 12-14 ml.kg-1 and that of low volume ventilation group was 6-8 ml.kg-1. Some indexes of airway pressures and blood gases were recorded and those of cardiovascular function were monitored continuously. The results were that compared to the normal volume ventilation group, the actual ventilation in liters per minute was lower obviously, the expiratory time longer, the incidence rate of lung barotrauma lower, peak inspiratory pressure, end-inspiratory-pressure, and internal positive-end-expiratory pressure smaller, and side-effect on hemodynamics less in the low volume group. The results suggest that low volume ventilation with permissive hypercapnia is better than normal volume ventilation in COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica/terapia , Respiração Artificial , Insuficiência Respiratória/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Respiração Artificial/métodos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , Volume de Ventilação Pulmonar
8.
Hunan Yi Ke Da Xue Xue Bao ; 25(6): 567-9, 2000 Dec 28.
Artigo em Chinês | MEDLINE | ID: mdl-12516407

RESUMO

OBJECTIVES: This study was explore the distribution of the bacteria and their sensibility to antibiotics in hospital-acquired pneumonia. METHODS: One hundred and ninety-six bacterium species were collected in patients with the hospital-acquired pneumonia to make sputum culture. The sensibility of the bacteria to antibiotics were examined by KB paper method and the minimal-inhibitory-concentration by gel double multiple dilute method. RESULTS: Most of the G- bacteria were pseudomonas aeruginosa (30%) and klebsiella bacillus (22%). Most of the G+ bacteria were staphylococcus epidermidis (14%) and staphylococcus aureus (12%). G- bacteria were sensitive to impienem(98%), cefoperazone(90%), ceftriaxone(90%), leftazidime(92%), ciprofloxacin(90%), and amikacin(89%). The sensibility of vancomycin to G+ bacteria was 100%. CONCLUSIONS: The pseudomonas aeruginosa, klebsiella bacillus, staphylococcus epidermidis, and staphylococcus aureus are the most important bacteria in patients with hospital-acquired pneumonia. Imipenem, cefoperazone, ceftriazone, leftazidime, ciprofloxacin, amikacin, and vancomycin are effective antibiotics for treating hospital-acquired pneumonia.


Assuntos
Infecção Hospitalar/microbiologia , Pneumonia Bacteriana/microbiologia , Infecções por Pseudomonas/microbiologia , Infecções Estafilocócicas/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cefoperazona/farmacologia , Ceftriaxona/farmacologia , Feminino , Humanos , Imipenem/farmacologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
10.
Hunan Yi Ke Da Xue Xue Bao ; 25(4): 363-6, 2000 Aug 28.
Artigo em Chinês | MEDLINE | ID: mdl-12206003

RESUMO

OBJECTIVE: To investigate the changes about nitric oxide(NO), endothelin(ET) derived from alveolar macrophages(AMs) and the effects of nitroglycerin(NTG) and mexamethason(DXM) on ET and NO in patients with mild and middle asthma. METHODS: The AMs from 7 healthy control subjects and 15 patients with attacking asthma were purified, and divided into healthy control unpretreated(Group 1), asthmatic unpretreated (Group 2), asthmatic pretreated by DXM(Group 3), asthmatic pretreated by NTG(Group 4). All purified AMs were cultured for 48 hours. The NO level and ET level in supernatant and the expression of iNOS-mRNA, ET-mRNA of cultured AM from above subjects were examined by copper coated cadmiunm reduction, radioimmunoassay method and in situ hybridization respectively. RESULTS: 1. The AM of Group 1 secreted a little of NO, ET and expressed a little of iNOS-mRNA and ET-mRNA; 2. The NO and ET level in supernatant and the expression of iNOS-mRNA and ET-mRNAin Group 2 were evidently higher than those in other groups(P < 0.05, respectively); 3. The NO and ET level in supernatant and the expression of iNOS-mRNA and ET-mRNA in Group 3 were evidently decreased, but they were still higher than those in Group 1(P < 0.05, respectively); 4. The NO level in Group 4 was higher than that in other groups(P < 0.05, respectively); 5. The expression of iNOS-mRNA was negatively correlated with the NO level(r = -0.59, P < 0.05), and the expression of ET-mRNA was positively correlated with the ET level(r = 0.92, P < 0.01) in Group 4. CONCLUSION: The AMs from patients with asthma exacerbation secrete a large quantity of NO and ET because of the increasing expression of iNOS-mRNA, ET-mRNA; DXM can inhibit the expression of iNOS-mRNA and ET-mRNA, and decrease NO and ET level, but the NO and ET level are still abnormal; NTG can improve directly the production of NO and inhibit significantly the expression of iNOS-mRNA and ET-mRNA as well as decrease the ET level.


Assuntos
Asma/metabolismo , Endotelinas/metabolismo , Macrófagos Alveolares/metabolismo , Óxido Nítrico/metabolismo , Nitroglicerina/farmacologia , Adulto , Células Cultivadas , Dexametasona/farmacologia , Feminino , Humanos , Macrófagos Alveolares/patologia , Masculino , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
12.
Singapore Med J ; 40(2): 88-90, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10414165

RESUMO

OBJECTIVES: To compare the laparoscopic approach with laparotomy in the treatment of ectopic pregnancy. The aim of this study was to evaluate the efficiency of laparoscopic surgery for ectopic pregnancies in China. METHOD: A retrospective analysis involving 142 patients with ectopic pregnancies was done. Seventy-two of the 142 patients were treated laparoscopically. RESULTS: In the laparoscopic group, the operating time and post-hospital stay were significantly shorter but the total cost was higher compared with the laparotomy group. CONCLUSION: Although the laparoscopic surgery for ectopic pregnancies is a new approach and it is not widely practiced in China; it has more advantages than open surgery and it has been well accepted by the surgeons and patients. It is a safe and feasible approach, but the rate of laparoscopic approach for ectopic pregnancy is still low in China when compared with the developed countries.


Assuntos
Laparoscopia , Laparotomia , Gravidez Ectópica/cirurgia , China , Análise Custo-Benefício , Feminino , Humanos , Laparoscopia/economia , Laparotomia/economia , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
13.
Biotechnol Bioeng ; 61(4): 227-41, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10494072

RESUMO

Combinatorial materials synthesis methods and high-throughput evaluation techniques have been developed to accelerate the process of materials discovery and optimization and phase-diagram mapping. Analogous to integrated circuit chips, integrated materials chips containing thousands of discrete different compositions or continuous phase diagrams, often in the form of high-quality epitaxial thin films, can be fabricated and screened for interesting properties. Microspot x-ray method, various optical measurement techniques, and a novel evanescent microwave microscope have been used to characterize the structural, optical, magnetic, and electrical properties of samples on the materials chips. These techniques are routinely used to discover/optimize and map phase diagrams of ferroelectric, dielectric, optical, magnetic, and superconducting materials.


Assuntos
Técnicas de Química Combinatória/métodos , Eletrônica , Magnetismo , Teste de Materiais , Microscopia/instrumentação , Micro-Ondas , Óptica e Fotônica/instrumentação
14.
Science ; 268(5218): 1738-40, 1995 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-17834993

RESUMO

A method that combines thin film deposition and physical masking techniques has been used for the parallel synthesis of spatially addressable libraries of solid-state materials. Arrays containing different combinations, stoichiometries, and deposition sequences of BaCO(3), Bi(2)O(3), CaO, CuO, PbO, SrCO(3), and Y(2)O(3) were generated with a series of binary masks. The arrays were sintered and BiSrCaCuO and YBaCuO superconducting films were identified. Samples as small as 200 micrometers by 200 micrometers in size were generated, corresponding to library densities of 10,000 sites per square inch. The ability to generate and screen combinatorial libraries of solid-state compounds, when coupled with theory and empirical observations, may significantly increase the rate at which novel electronic, magnetic, and optical materials are discovered and theoretical predictions tested.

15.
Science ; 256(5060): 1190-1, 1992 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-17795215

RESUMO

Sizable single crystals of C(6O) have been synthesized and doped with potassium. Above the superconducting transition temperature T(c), the electrical resistivity p(T) displays a classic metal-like temperature dependence. The transition to the superconducting state at T(c) = 19.8 K is extremely sharp, with a transition width DeltaT < 200 mK. In contrast to transport behavior of doped polycrystalline and granular thin films, no anomalous fluctuations are observed near T(c) in single crystal specimens.

16.
Science ; 254(5037): 1487-9, 1991 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-17773298

RESUMO

Multistage intercalation has been used to tune the interaction between adjacent blocks of CuO(2) sheets in the bigh-T(c) (high superconducting transition temperature) superconductor Bi(2)Sr(2)CaCu(2)Ox. As revealed by atomic-resolution transmission electron microscopy images, foreign iodine atoms are intercalated into every nth BiO bilayer of the host crystal, resulting in structures of stoichiometry IBi2nSr2nCanCu2nOx with stage index n up to 4. An expansion of 3.6 angstroms for each intercalated BiO bilayer decouples the CuO(2) sheets in adjacent blocks. A comparison of the superconducting transition temperatures of the pristine host material and intercalated compounds of different stages suggests that the coupling between each pair of adjacent blocks contributes approximately 5 K to T(c) in Bi(2)Sr(2)CaCu(2)Ox.

17.
Artigo em Chinês | MEDLINE | ID: mdl-2517413

RESUMO

Schistosoma japonicum daughter sporocysts in Oncomelania tissue sections were, for the first time, used as antigen in the diagnosis of schistosomiasis japonica by indirect immunoperoxidase assay (IIPA-DS). The most strong peroxidase reaction was localized on the tegument of the daughter sporocysts and cercariae, and at some parts of cercarial parenchyma, when IIPA-DS was carried out. Of 112 sera from proven cases of schistosomiasis japonica, 106 (94.6%) were positive, the range of titre dilution was from 1:1 to 1:160, the geometric mean of titres was 1:20. IIPA-DS highly coincided with IHA, COP and ELISA in both sensitivity and strength of reaction. Sera from 101 blood donors and 24 normal rabbits were all negative. No cross reaction with sera from 24 patients with paragonimiasis was observed.


Assuntos
Antígenos de Helmintos/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/diagnóstico , Animais , Humanos , Técnicas Imunoenzimáticas , Larva/imunologia , Caramujos/parasitologia
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