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1.
RSC Adv ; 10(40): 23944-23952, 2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-35517337

RESUMEN

We present an ab initio molecular dynamics study of the thermal stability and dynamics behaviors of lattice misalignment structures (LMSs) in the subsurface layers of KH2PO4 (KDP) crystals. The dehydration process at the atomic scale is observed in the LMS system, which is the same as that in a perfect KDP crystal. However, the paths entering the dehydration process are various. The interesting result is that compared with a perfect KDP crystal, many new paths appear in the LMS system, and even in the same paths, the dehydration is more likely to happen in the LMS system. This leads to a dramatic increase in the dehydration numbers in the LMS system, for which the reasons are given in terms of structural deformation and/or uneven distribution of protons. The results elucidate the underlying atomic mechanism of the effect of LMS defects on the thermal stability of KDP material.

2.
Phys Chem Chem Phys ; 18(30): 20635-9, 2016 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-27411860

RESUMEN

The band engineering of M-doped SnTe (M = Ga, In, and Tl) is investigated by using first-principles calculations. Being consistent with experimental measurements, our calculations found that Ga doping hardly changes the valence band, while In doping introduces an obvious resonant state near the Fermi level. The resonant state is demonstrated to be from the anti-bonding of In-s and Te-p orbitals. Unexpectedly, no resonant state was observed in Tl-doped SnTe, indicating the nonmonotonic behavior of the Ga-In-Tl series. We show that the absence of the resonant state in Tl-doped SnTe is due to the downward shift of the Tl-s orbital, which may be attributed to the effect of lanthanide contraction. The increase of the Seebeck coefficient in In-doped SnTe is numerically confirmed by Boltzmann transport calculations. Moreover, we find that the mutually matched resonant state location and valence band separation is the key precondition for the combination of the resonant state and band convergence in SnTe. A further enhanced Seebeck coefficient (∼230 µV K(-1)) and ZT value (1.8 at 920 K) are predicted in codoped SnTe by In-Hg, owing to the synergy of two kinds of band engineering.

3.
Phys Chem Chem Phys ; 18(10): 7141-7, 2016 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-26888151

RESUMEN

The electronic structures of M-doped SnTe (M = Mg, Mn, Cd, and Hg) are investigated by using first-principles calculations including spin-orbit coupling. It is found that Sn vacancy plays an important role in the band engineering of SnTe, showing a different property from its related compound PbTe. The enlarged band gap and reduced energy separation between two valence bands are in good agreement with experimental measurements. Both of the two band modifications lead to the increase of Seebeck coefficients, which is explicitly confirmed by the followed Boltzmann transport calculations. The calculated Seebeck coefficients for Mn-doped SnTe agree well with the experimental data in a broad range of carrier concentration. Owing to the improved Seebeck coefficients, Mn- and Cd-doped SnTe exhibit promising thermoelectric properties with ZT = 1.32 and 1.65 at around 800 K, respectively.

4.
Cell Mol Biol (Noisy-le-grand) ; 61(1): 1-6, 2015 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-25817339

RESUMEN

The binding of selectin to P—selectin glycoprotein ligand—1 (PSGL—1) mediates the tethering and rolling of leukocytes on the endothelium during leukocyte migration and inflammation. Recombinant human PSGL—1—Ig fusion protein (rPSGL—1—Ig) is a widely used selectin inhibitor that prevents neutrophil entry into inflamed or reperfused tissues. We hypothesized that rPSGL—1—Ig could be used to as a drug for the treatment of acute lung injury (ALI). We induced murine ALI by injecting mice with lipopolysaccharide (LPS) and then treated the mice with rPSGL—1—Ig. We determined the lung injury index, wet/dry ratio, and inflammatory cytokine level in differentially treated mice. The symptoms of LPS—induced lung injury were alleviated by rPSGL—1—Ig treatment. The histopathological index of LPS—induced lung injury improved after rPSGL—1—Ig treatment. rPSGL—1—Ig treatment also reduced the recruitment of inflammatory cells, including neutrophils, into the lung, as well as reducing the level of inflammatory cytokines. These data suggest that rPSGL—1—Ig protein has a therapeutic effect on LPS—induced lung injury.


Asunto(s)
Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/prevención & control , Movimiento Celular/efectos de los fármacos , Inmunoglobulina G/farmacología , Lipopolisacáridos/efectos adversos , Glicoproteínas de Membrana/farmacología , Neutrófilos/patología , Lesión Pulmonar Aguda/patología , Animales , Lavado Broncoalveolar , Recuento de Células , Movimiento Celular/fisiología , Modelos Animales de Enfermedad , Femenino , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos C57BL , Neutrófilos/efectos de los fármacos , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes/farmacología , Factor de Necrosis Tumoral alfa/metabolismo
5.
J Int Med Res ; 36(3): 537-43, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18534136

RESUMEN

This study explored the efficacy and safety of combination pharmacological cardioversion of permanent atrial fibrillation in outpatients following prosthetic mitral valve replacement. The study group comprised 99 outpatients who were randomly divided into two groups. In group 1 (n = 50), only ventricular heart rate was controlled. In group 2 (n = 49), combination pharmacological cardioversion therapy with low-dose oral amiodarone (2 mg/kg), captopril (0.25 mg/kg) and simvastatin (0.3 mg/kg) was administered daily. During 12 months of serial pharmacological treatment, the cardioversion rate was 6% for group 1 and 39% for group 2; the likelihood of cardioversion differed significantly between the two groups. In group 2, one patient developed severe pruritus that necessitated withdrawal from the study and six patients ceased captopril treatment after contracting a persistent cough. In summary, combination pharmacological cardioversion was found to be effective and safe in outpatients who had undergone prosthetic mitral valve replacement.


Asunto(s)
Antiarrítmicos/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Cardioversión Eléctrica , Prótesis Valvulares Cardíacas , Válvula Mitral/patología , Adulto , Antiarrítmicos/efectos adversos , Terapia Combinada , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pacientes Ambulatorios , Resultado del Tratamiento
6.
Genet Anal ; 15(6): 205-7, 1999 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-10609755

RESUMEN

Southern blotting, PCR, DGGE and DNA sequencing were used to study gene mutations in 52 unrelated Chinese Hemophilia A patients. 18 out of 34 severe cases had intron 22 inversions, 13 had small gene lesions, of which five are novel.


Asunto(s)
ADN/análisis , Hemofilia A/genética , China , Inversión Cromosómica , Electroforesis en Gel de Poliacrilamida , Factor VIII/genética , Humanos , Intrones , Mutación Puntual , Reacción en Cadena de la Polimerasa
7.
Hematopathol Mol Hematol ; 10(1-2): 63-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8792148

RESUMEN

Hemophilia A is an X-linked bleeding disorder caused by deleterious mutations in the factor VIII gene. An inversion caused by introchromosomal homologous recombination between the A gene located in intron 22 of the factor VIII gene and one of the two telomeric A genes has been recently described as the common cause of about 50% of cases of severe hemophilia A. The rearrangement can be readily detected by a Southern blotting procedure. We report use of this procedure to detect rearrangements in 106 unrelated Chinese hemophilia A cases. In 49.3% of the patients with severe disease an inversion was found, but no inversion was detected in any of the patients with moderate or mild disease. The majority of inversions (91.4%) involved the most distal A gene; in a minority (8.6%) the more proximal A gene was involved. These results indicate that intron 22 inversion is the most important molecular defect causing Chinese hemophilia A and that analysis for intron 22 inversion may be the first-line test in the molecular diagnosis of severe hemophilia A.


Asunto(s)
Pueblo Asiatico/genética , Inversión Cromosómica , Factor VIII/genética , Pruebas Genéticas/métodos , Hemofilia A/diagnóstico , Southern Blotting , China , Reordenamiento Génico , Hemofilia A/genética , Humanos , Masculino
9.
Yao Xue Xue Bao ; 28(3): 181-7, 1993.
Artículo en Chino | MEDLINE | ID: mdl-8103617

RESUMEN

In this paper, the synthesis and analgesic activities of some derivatives of 4-methoxycarbonyl fentanyl are reported, in which the 4-N-phenyl group or both the 4-N-phenyl group and the 1-beta-phenyl group were replaced by some nonaromatic groups. In the last case, some compounds showed very strong analgesic activity. For example, the analgesic activities of compounds 4 and 6 were shown to be 695 and 818 times more potent than that of morphine respectively. The structure-analgesic activity relationships were discussed.


Asunto(s)
Analgésicos Opioides/síntesis química , Fentanilo/análogos & derivados , Analgésicos Opioides/química , Analgésicos Opioides/farmacología , Animales , Femenino , Fentanilo/síntesis química , Fentanilo/química , Fentanilo/farmacología , Ratones , Umbral del Dolor/efectos de los fármacos , Relación Estructura-Actividad
10.
Chin Med J (Engl) ; 102(1): 67-71, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2504556

RESUMEN

Thirteen hypercoagulation parameters related to coagulation, anticoagulation, platelet functions, dynamics of clot formation and hemorrheology were determined in 15-109 patients with thromboangiitis obliterans (TAO). The results showed that VIIIR = Ag, PAdT, PagT, HPF, and whole blood and plasma viscosity were elevated, fibrinogen elevated in the active stage, AT-III declined, RBC electrophoresis time prolonged, and changes suggesting hypercoagulation in thromboelastogram. All these indicated the existence of a hypercoagulation state in TAO patients, which could contribute to the process of thrombosis. The relationship between immune reactions and blood hypercoagulability could be crucial in the pathogenesis of TAO. Immune reactions causing injury of vascular endothelium play a primary and fundamental role, and blood hypercoagulability could play a secondary but important role in the course of the disease.


Asunto(s)
Antígenos/análisis , Antitrombina III/análisis , Viscosidad Sanguínea , Factor VIII/inmunología , Tromboangitis Obliterante/sangre , Adulto , Factor VIII/análisis , Humanos , Masculino , Persona de Mediana Edad , Tromboangitis Obliterante/etiología , Factor de von Willebrand
11.
Shengzhi Yu Biyun ; 8(1): 22-6, 1988.
Artículo en Chino | MEDLINE | ID: mdl-12315407

RESUMEN

PIP: The authors studied the effect of a new injectable contraceptive, a megestrol acetate compound, on blood coagulation, anticoagulation activity, fibrinolysis, platelet count, and its aggregation. The results indicate that after the administration of this contraceptive for over 1 year, VII:C and VIIIR:Ag were significantly increased and PT was shortened. Fibrinogen antigen decreases were seen within 6 months of administration, and then these returned to normal. Antithrombin III activity and antigen levels did not change during the time this contraceptive was in use. Plasminogen and fibrinolytic activity were significantly increased after the administration of the contraceptive for more than 3 years. Platelet aggregation induced by ADP increased after the contraceptive was in use for more than 1 year. (author's modified)^ieng


Asunto(s)
Coagulación Sanguínea , Sangre , Fibrinólisis , Hormonas , Acetato de Megestrol , Agregación Plaquetaria , Sustancias para el Control de la Reproducción , Biología , Anticoncepción , Anticonceptivos , Anticonceptivos Femeninos , Sistema Endocrino , Servicios de Planificación Familiar , Fisiología
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