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J Phys Chem Lett ; 6(9): 1568-72, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-26263315


The vibrationally resolved X-ray photoelectron spectra of X2Σg+(3σg−1) and B2Σu+(2σu−1) states of N2+ were recorded for different photon energies and orientations of the polarization vector. Clear dependencies of the spectral line widths on the X-ray polarization as well as on the symmetry of the final electronic states are observed. Contrary to the translational Doppler, the rotational Doppler broadening is sensitive to the photoelectron emission anisotropy. On the basis of theoretical modeling, we suggest that the different rotational Doppler broadenings observed for gerade and ungerade final states result from a Young's double-slit interference phenomenon.

Nat Commun ; 5: 3816, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24809410


Due to the generally delocalized nature of molecular valence orbitals, valence-shell spectroscopies do not usually allow to specifically target a selected atom in a molecule. However, in X-ray electron spectroscopy, the photoelectron momentum is large and the recoil angular momentum transferred to the molecule is larger when the photoelectron is ejected from a light atom compared with a heavy one. This confers an extreme sensitivity of the rotational excitation to the ionization site. Here we show that, indeed, the use of high-energy photons to photoionize valence-shell electrons of hydrogen chloride offers an unexpected way to decrypt the atomic composition of the molecular orbitals due to the rotational dependence of the photoionization profiles. The analysis of the site-specific rotational envelopes allows us to disentangle the effects of the two main mechanisms of rotational excitation, based on angular momentum exchange between the molecule and either the incoming photon or the emitted electron.

Nan Fang Yi Ke Da Xue Xue Bao ; 30(11): 2577-80, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21097438


OBJECTIVE: To evaluate the efficacy and safety of amiodarone and metoprolol in the treatment of ventricular premature beats. METHODS: Controlled randomized clinical trials from 1999 through 2009 were retrieved in China HowNet, VIP Web, Pubmed home. Using Rev Man4.2 software provided by Cochrane Collaboration, Meta-analysis was conducted of 30 articles meeting the inclusion criteria involving a total of 1188 patients. RESULTS: Merged analysis of amiodarone and metoprolol in the treatment of premature ventricular merge showed a comprehensive test results of Z=1.25, P=0.21, OR=1.18, 95%CI: 0.91-1.54; funnel plot analysis suggested the possible presence of publication bias. The comprehensive test of the incidence of adverse reactions in relation to the two drugs resulted in an OR of 1.96 (95%CI: 1.39-2.77), and funnel plot analysis also indicated publication bias. CONCLUSIONS: The total response rate of amiodarone does not seem to be superior to metoprolol in the treatment of premature ventricular contractions, and amiodarone is associated with higher incidence of adverse reactions.

Amiodarona , Metoprolol , Complexos Ventriculares Prematuros/tratamento farmacológico , Amiodarona/efeitos adversos , Amiodarona/uso terapêutico , Quimioterapia Combinada , Humanos , Metoprolol/efeitos adversos , Metoprolol/uso terapêutico , Resultado do Tratamento
Microb Pathog ; 46(4): 194-200, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19167479


Vibrio vulnificus cytolysin (VVC) is known to be a pore-forming toxin which shows cytotoxicity for mammalian cells in culture and induces apoptosis in endothelial cells. In order to determine whether VVC induces apoptosis in vascular endothelial cells and tumor cells, the cytotoxicity induced by recombinant VVC (rVVC) and its potential mechanism in HUVEC, SGC-7901 and SMMC-7721 cells were investigated. Our study demonstrated that rVVC induced the release of intracellular K(+) from all the target cells, yet lactate dehydrogenase was not released by rVVC. It indicates that osmotic lysis might not contribute to the cytolysin-induced cytotoxicity. The study also demonstrated that rVVC induced apoptosis in HUVEC, SGC-7901 and SMMC-7721 cells in time- and dosage-dependent manners, which was associated with the activation of caspase-9 and -3, but not caspase-8. During the apoptotic process of the target cells, rVVC labeled with FITC was monitored to attach initially to the surface of the cells and entered the cytoplasma subsequently. These findings suggest that VVC may be not only a pore-forming toxin, but also a transmembrane toxin with powerful ability to induce apoptosis in human vascular endothelial cells and tumor cells.

Apoptose , Caspase 3/metabolismo , Caspase 9/metabolismo , Células Endoteliais/efeitos dos fármacos , Perforina/toxicidade , Vibrio vulnificus/patogenicidade , Caspase 8/metabolismo , Linhagem Celular Tumoral , Membrana Celular/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoplasma/química , Células Epiteliais/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Potássio/metabolismo
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 31(6): 448-452, 2002 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-12601863


OBJECTIVE: To examine the use of PCR utilizing 16S-23S rRNA gene spacer regions in the identification of bacteria. METHODS Primers used in PCR were designed by using the target sequences from the genes encoding 16S-23S rRNA spacer regions. PCR was used for the detection of different standard and clinical bacterial strains. RESULTS Characteristic DNA maps were present after using the PCR to identify 27 standard strains from 27 species. The maps could be directly used for classification of the tested bacterial strains or further differentiated by RFLP. The sensitivity of the PCR may be as high as 2.5 CFU/ml. No non-specific amplification products were observed when using DNA from human PBMC funguses or viruses as templates. Thirty-two strains of bacteria isolated from clinical strains showed DNA maps similar to the DNA maps amplified from standard strains. CONCLUSION The PCR detection of bacteria using 16S-23S rRNA gene spacer regions is sensitive, rapid, specific and accurate for identification of bacteria and provides a new rapid method for determining the clinical diagnosis and the etiology of sepsis.