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1.
Yao Xue Xue Bao ; 51(1): 153-6, 2016 Jan.
Artículo en Zh | MEDLINE | ID: mdl-27405178

RESUMEN

The regulation mechanism of arecoline on rat hepatic CYP2E1 was studied in vivo. After oral administration of arecoline hydrobromide (AH; 4, 20 and 100 mg x kg(-1) x d(-1)) to rats for one week, the hepatic CYP2E1 mRNA level remained unchanged, but the hepatic CYP2E1 protein content was dose-dependently increased. Additionally, although the hepatic CYP2E1 activity was induced by AH treatment, the induction was attenuated with the increase in dosage. The results indicate that the effect of arecoline on rat hepaticdoes not involve transcriptional activation of the gene, but largely involves the stabilization of CYP2E1 protein against degradation or increased efficiency of CYP2E1 mRNA translation, and additionally involve the post- ranslational modification of CYP2E1 protein. Furthermore, the CYP2E1 response is fairly equal among the different species, the induction of rat hepatic CYP2E1 by arecoline suggests that there is a risk of metabolic interaction among the substrate drugs of CYP2E1 in betel-quid use human.


Asunto(s)
Arecolina/farmacología , Inductores del Citocromo P-450 CYP2E1/farmacología , Citocromo P-450 CYP2E1/metabolismo , Hígado/efectos de los fármacos , Animales , Humanos , Hígado/metabolismo , ARN Mensajero , Ratas
2.
Opt Express ; 22(8): 9182-92, 2014 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-24787808

RESUMEN

The continuous-variable (CV) quadratic phase gate is one of the most fundamental CV quantum gates for universal CV quantum computation, while its experimental realization still remains a challenge. Here we propose a novel and experimentally feasible scheme to realize optical CV quadratic phase gate via Faraday interaction in an atomic ensemble. The gate is performed by simply sending an optical beam three times through an atomic medium prepared in coherent spin state. The fidelity of the gate can ideally run up to one. We show that the scheme also works well as a device to generate optical polarization squeezing. Considering the noise effects due to atomic decoherence and light losses, we find that the observed fidelities of gate operation and the attainable degree of polarization squeezing are still quite high.

3.
Shanghai Kou Qiang Yi Xue ; 33(3): 318-323, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-39104351

RESUMEN

PURPOSE: To investigate the correlation between the occlusal canting and the bilateral temporomandibular joint (TMJ) space in adult and juvenile mandibular deviation patients and study the mutual influence between the occlusal canting and mandibular position, in order to provide references for clinical treatment. METHODS: CBCT data of mandibular deviation patients(20 adults,20 juveniles)were selected. Inivo5 Dental Anatomage software was used to reconstruct the structures. The occlusal cant and vertical height of the bilateral maxillary from canines to first molars were measured, and the vertical heights difference between the same teeth on both sides was calculated. The anterior, superior and posterior space of temporomandibular joint were measured respectively in both groups. Pearson correlation analysis between the occlusal canting and bilateral condylar space was carried out by using SPSS 17.0 software package. RESULTS: In the juvenile group, negative correlations were found between the occlusal cant and the superior TMJ space on the deviated side (P<0.05). Negative correlation was found between the vertical height difference of bilateral canines and the anterior TMJ space on the deviated side in the juvenile group(P<0.05). In the adult group, no significant correlation was observed among those correlated examination (P>0.05). CONCLUSONS: The occlusal canting is moderately correlated with mandibular position in the early stage of mandibular deviation patients. Early treatment of mandibular deviation is of great importance in preventing its progression into severe skeletal malocclusion, and more attention should be paid on the correction of the canted frontal occlusion plane.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Mandíbula , Articulación Temporomandibular , Humanos , Articulación Temporomandibular/diagnóstico por imagen , Mandíbula/anatomía & histología , Tomografía Computarizada de Haz Cónico/métodos , Maloclusión , Oclusión Dental , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/crecimiento & desarrollo
4.
Acta Crystallogr C ; 69(Pt 8): 855-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23907875

RESUMEN

Details of the structures of two polymorphs of tris(ethylenediamine)cobalt(III) tetrathioantimonate(V), [Co(C2H8N2)3][SbS4], are reported. The first polymorph crystallizes in the orthorhombic space group Pna21, whereas the second polymorph belongs to the tetragonal space group P42bc. Both structures contain octahedral [Co(en)3]³âº cations (en is ethylenediamine) and tetrahedral [SbS4]³â» anions, which are interconnected via various N-H∙∙∙S hydrogen bonds to form two different types of three-dimensional network.

5.
J Asian Nat Prod Res ; 14(2): 154-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22296155

RESUMEN

Two new xanthones, angustins A and B (1 and 2), were isolated from the aerial parts of Swertia angustifolia together with six known compounds (3-8). The structures of these two xanthones were elucidated by extensive analysis of the spectroscopic data. In addition, compounds 3 and 6-8 were isolated from this plant for the first time.


Asunto(s)
Medicamentos Herbarios Chinos/aislamiento & purificación , Swertia/química , Xantonas/aislamiento & purificación , Medicamentos Herbarios Chinos/química , Estructura Molecular , Xantonas/química
6.
Huan Jing Ke Xue ; 43(1): 369-376, 2022 Jan 08.
Artículo en Zh | MEDLINE | ID: mdl-34989521

RESUMEN

Due to increasing active nitrogen pollution loads, river systems have become an important source of nitrous oxide (N2O) in many areas. Due to the lack of monitoring data in many studies as well as the difficulty in estimating intermediate parameters and expressing temporal-spatial variability in current methods, a high level of uncertainty remains in the estimates of riverine N2O emission quantity. Based on the monthly monitoring efforts conducted for 10 sampling sites across the Yonganxi River system in Zhejiang Province from June 2016 to July 2019, the temporal and spatial dynamics of riverine N2O dissolved concentrations ρ(N2O), N2O fluxes, and their influencing factors were addressed. A multiple regression model was then developed for predicating riverine N2O emission flux to estimate annual N2O emission quantity for the entire river system. The results indicated that observed riverine ρ(N2O) (0.03-2.14 µg·L-1) and the N2O fluxes[1.32-82.79 µg·(m2·h)-1] varied by 1-2 orders of magnitude of temporal-spatial variability. The temporal and spatial variability of ρ(N2O) were mainly influenced by the concentrations of nitrate, ammonia, and dissolved organic carbon, whereas the N2O emission fluxes were mainly affected by river water discharges and ρ(N2O). A multiple regression model that incorporates variables of river water discharge and ρ(N2O) could explain 90% of the variability in riverine N2O emission fluxes and has high accuracy. The model estimated N2O emission quantity from the entire Yonganxi River system of 3.67 t·a-1, with 29% from the main stream and 71% from the tributaries. The IPCC default emission factor method might greatly overestimate and underestimate N2O emission quantities for rivers impacted by low and high pressures of human activities, respectively. This study advances our quantitative understanding of N2O emission for the entire river system and provides a reference method for estimating riverine N2O emission with more accuracy.


Asunto(s)
Óxido Nitroso , Ríos , Materia Orgánica Disuelta , Monitoreo del Ambiente , Humanos , Óxido Nitroso/análisis , Agua
7.
Genes Genomics ; 44(11): 1363-1374, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36125655

RESUMEN

BACKGROUND: Smoking behavior is influenced by multiple genes, including the bitter taste gene TAS2R38. It has been reported that the correlation between TAS2R38 and smoking behavior has ethnicity-based differences. However, the TAS2R38 status in Chinese smokers is still unclear. OBJECTIVE: This study aims to investigate the possible relationship between genetic variations in TAS2R38 (A49P, V262A and I296V) and smoking behaviors in the Han Chinese population. METHODS: The haplotype analyses were performed and smoking behavior questionnaire was completed by 1271 individuals. Genetic association analyses for smoking behavior were analyzed using chi-square test. Further, for investigating the molecular mechanism of TAS2R38 variants effect on smoking behavior, we conducted TAS2R38-PAV and TAS2R38-AVI expression plasmids and tested the cellular calcium assay by cigarette smoke compounds stimulus in HEK293. RESULTS: Significant associations of genetic variants within TAS2R38 were identified with smoking behavior. We found a higher PAV/PAV frequency than AVI/AVI in moderate and high nicotine dependence (FTND ≥ 4; X2 = 4.611, 1 df, p = 0.032) and strong cigarette smoke flavor intensity preference (X2 = 4.5383, 1 df, p = 0.033) in participants. Furthermore, in the in vitro cellular calcium assay, total particle matter (TPM), N-formylnornicotine and cotinine, existing in cigarette smoke, activated TAS2R38-PAV but not TAS2R38-AVI-transfected cells. CONCLUSION: Our data highlights that genetic variations in TAS2R38 are related to smoking behavior, especially nicotine dependence and cigarette smoke flavor intensity preference. Our findings may encourage further consideration of the taste process to identify individuals susceptible to nicotine dependence, particularly Han Chinese smokers.


Asunto(s)
Fumar Cigarrillos , Tabaquismo , Calcio , China , Cotinina , Variación Genética , Células HEK293 , Humanos , Receptores Acoplados a Proteínas G/genética , Fumadores , Gusto/genética
8.
Hepatobiliary Pancreat Dis Int ; 10(4): 374-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21813385

RESUMEN

BACKGROUND: Ischemia-related biliary tract complications remain high after orthotopic liver transplantation. Severe ischemic biliary complications often involve the hepatic duct bifurcation and left hepatic duct, resulting finally in obstructive jaundice. Prevention and management of such complications remain a challenge for transplant surgeons. METHODS: All 160 patients were followed up for at least 180 days after transplantation. One-way analysis of variance (ANOVA) and comparative univariate analysis were made using 3 groups (no complications; mild complications; severe complications), to analyze risk factors associated with biliary complications. Multiple logistic regression and linear regression analysis were used to analyze independent risk factors for severe ischemic biliary complications, after excluding other confounding factors. RESULTS: By ANOVA and comparative univariate analysis, the risk factors associated with biliary complications were preoperative bilirubin level (P=0.007) and T-tube stenting of the anastomosis (P=0.016). Multiple logistic regression analysis showed that the use of T-tube and preoperative serum bilirubin were not independent risk factors for severe ischemic biliary complications after orthotopic liver transplantation. Chi-square analysis indicated that in the incidence of severe ischemic biliary lesions, bile duct second warm ischemic time longer than 60 minutes was a significant risk factor. Linear regression demonstrated a negative correlation between cold preservation time and warm ischemia time. CONCLUSIONS: Preoperative serum bilirubin level and the use of T-tube stenting of the anastomosis were independent risk factors for biliary complications after liver transplantation, but not for severe ischemic biliary complications. The second warm ischemia time of bile duct longer than 60 minutes and prolonged bile duct second warm ischemia time combined with cold preservation time were significant risk factors for severe ischemic biliary complications after liver transplantation with grafts from non-heart-beating donors.


Asunto(s)
Enfermedades de las Vías Biliares/etiología , Isquemia/etiología , Trasplante de Hígado/efectos adversos , Adolescente , Adulto , Anciano , Análisis de Varianza , Enfermedades de las Vías Biliares/diagnóstico , Bilirrubina/sangre , Biomarcadores/sangre , Distribución de Chi-Cuadrado , China , Isquemia Fría/efectos adversos , Femenino , Humanos , Isquemia/diagnóstico , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Stents/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Isquemia Tibia/efectos adversos , Adulto Joven
9.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): o1581, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21836991

RESUMEN

The asymmetric unit of the title compound, C(8)H(6)N(2)O(2)·C(8)H(5)NO(6)·H(2)O, contains mol-ecules of 1,4-dihydro-quinoxaline-2,3-dione, 5-nitro-isophthalic acid and a solvent water. In the crystal structure, mol-ecules are linked into a three-dimensional network by inter-molecular N-H⋯O and O-H⋯O hydrogen bonds.

10.
Hepatobiliary Pancreat Dis Int ; 9(6): 593-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21134827

RESUMEN

BACKGROUND: The ischemic-type biliary lesion (ITBL) is one of the most serious biliary complications of liver transplantation. This study aimed to investigate the effects of autologous bone marrow mononuclear cell (BM-MNC) implantation on neovascularization and the prevention of intrahepatic ITBL in a rabbit model. METHODS: The rabbits were divided into control, experimental model, and cell implantation groups, with 10 in each group. The model of intrahepatic ITBL was established by clamping the hepatic artery and common bile duct. Autologous BM-MNCs were isolated from the tibial plateau by density gradient centrifugation and were implanted through the common hepatic artery. Changes in such biochemical markers as aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyltranspeptidase, total bilirubin and direct bilirubin were measured. Four weeks after operation, cholangiography, histopathological manifestations, differentiation of BM-MNCs, microvessel density and the expression of vascular endothelial growth factor were assessed. RESULTS: Compared with the experimental model group, the BM-MNC implantation group showed superiority in the time to recover normal biochemistry. The microvessel density and vascular endothelial growth factor expression of the implantation group were significantly higher than those of the control and experimental model groups. The ITBL in the experimental model group was more severe than that in the implantation group and fewer new capillary blood vessels occurred around it. CONCLUSIONS: Implanted autologous BM-MNCs can differentiate into vascular endothelial cells, promote neovascularization and improve the blood supply to the ischemic bile duct, and this provides a new way to diminish or prevent intrahepatic ITBL after liver transplantation.


Asunto(s)
Conductos Biliares Intrahepáticos/patología , Trasplante de Médula Ósea/métodos , Isquemia/terapia , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias , Animales , Células de la Médula Ósea/citología , Diferenciación Celular/fisiología , Células Endoteliales/citología , Femenino , Isquemia/patología , Masculino , Neovascularización Fisiológica/fisiología , Complicaciones Posoperatorias/patología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/terapia , Conejos , Tasa de Supervivencia , Trasplante Autólogo
11.
Nat Prod Res ; 34(10): 1423-1429, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30453776

RESUMEN

Two new xanthone glycosides (1-2), together with seven known analogues (3-9), were isolated from whole herb of Swertia punicea. The structures of these metabolites were established on the basis of detailed spectroscopic analysis and comparison with data reported in the literature. In an in vitro test, all isolates were evaluated for their anti-inflammatory activity. The results revealed that all of them showed significant anti-inflammatory activity with IC50 values ranging from 1.237 to 3.319 mM. Compounds 3, 4, and 5 (IC50 values in the range 1.237-1.987 mM) displayed more potent anti-inflammatory activity than the positive control, indomethacin (IC50 value of 2.004 mM).


Asunto(s)
Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Swertia/química , Xantonas/química , Animales , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/química , Glicósidos/química , Espectroscopía de Resonancia Magnética , Ratones , Estructura Molecular , Células RAW 264.7
12.
Shanghai Kou Qiang Yi Xue ; 27(4): 386-389, 2018 Aug.
Artículo en Zh | MEDLINE | ID: mdl-30483706

RESUMEN

PURPOSE: To investigate the changes of condyle position by decreasing posterior occlusal plane angle in Class II high angle cases. METHODS: Fifteen Class II high angle patients, aged from 15 to 30, were treated. Before treatment, ANB>5°, FH-MP>32°, molar relationship was Class II bilaterally. The treatment began with aligning and leveling the upper and lower dental arch, then the upper arch was expanded when necessary. Multiloop edgewise arch wire (MEAW) was used to guide the mandible forward and flatten the posterior occlusal plane. Cone-beam CT(CBCT) was taken for each patient before and after treatment. The anterior, superior and posterior spaces of temporomandibular joint(TMJ) were measured respectively, and the posterior occlusal plane angle was also measured. Paired t test was used to evaluate the changes of condyle position and posterior occlusal plane angle, and pearson correlation coefficients was used to determine the correlation between changes of condyle position and posterior occlusal plane angle using SPSS 19 software package. RESULTS: Class II molar relationship of all patients was improved to Class I, and the profile was improved. Posterior and superior space of TMJ increased by 0.88 mm±0.17 mm and 0.45 mm±0.20 mm on average respectively, and both increases were significant. Posterior occlusal plane was flattened, POP-SN and POP-FH decreased by 3.59°±2.31° and 2.31°±3.62°, respectively, and the decreases were significant. Pearson's correlation test showed no significant correlation between changes of condyle position and posterior occlusal plane angle. CONCLUSIONS: In orthodontic treatment of Class II high angle cases, the condyle can be changed to anterior and inferior position by decreasing posterior occlusal plane angle.


Asunto(s)
Oclusión Dental , Maloclusión Clase II de Angle , Cóndilo Mandibular , Cefalometría , Humanos , Maloclusión , Articulación Temporomandibular
13.
Nat Prod Res ; 30(16): 1810-5, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26329818

RESUMEN

Two new xanthones (1-2), together with four known ones (3-6), were isolated from whole herb of Swertia elata. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Their anti-tobacco mosaic virus (anti-TMV) activity test revealed that 1-6 showed weak anti-TMV activities with inhibition rate in the range of 15.2-28.8% at the concentration of 20 µM.


Asunto(s)
Swertia/química , Virus del Mosaico del Tabaco/efectos de los fármacos , Xantonas/aislamiento & purificación , Antivirales/química , Antivirales/aislamiento & purificación , Antivirales/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Xantonas/química , Xantonas/farmacología
14.
Int J Stomatol Occlusion Med ; 6: 120-129, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24273616

RESUMEN

INTRODUCTION: The aim of the present study was to evaluate how vertical facial height correlates with mandibular plane angle, facial width and depth from a three dimensional (3D) viewing angle. METHODS: In this study 3D cephalometric landmarks were identified and measurements from 43 randomly selected cone beam computed tomography (CBCT) images of dry skulls from the Weisbach collection of Vienna Natural History Museum were analyzed. Pearson correlation coefficients of facial height measurements and mandibular plane angle and the correlation coefficients of height-width and height-depth were calculated, respectively. RESULTS: The mandibular plane angle (MP-SN) significantly correlated with ramus height (Co-Go) and posterior facial height (PFH) but not with anterior lower face height (ALFH) or anterior total face height (ATFH). The ALFH and ATFH showed significant correlation with anterior cranial base length (S-N), whereas PFH showed significant correlation with the mandible (S-B) and maxilla (S-A) anteroposterior position. CONCLUSIONS: High or low mandibular plane angle might not necessarily be accompanied by long or short anterior face height, respectively. The PFH rather than AFH is assumed to play a key role in the vertical facial type whereas AFH seems to undergo relatively intrinsic growth.

15.
J Microbiol ; 51(3): 289-94, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23812807

RESUMEN

A Gram-positive, catalase- and oxidase-positive, strictly aerobic, endospore-forming rod bacterium, designated K3514(T), was isolated from the leaves of Nicotiana tabacum. The strain was able to grow at temperatures of 8-40°C, pH 5.0-10.0 and NaCl concentrations of 0-7%. The predominant quinones (>30%) of this strain were MK-7(H2) and MK-7. Phylogenetic analysis of 16S rRNA gene sequence showed that strain K3514(T) was affiliated to the genus Lysinibacillus, with its closest relatives being Lysinibacillus mangiferihumi (98.3% sequence similarity), Lysinibacillus sphaericus (97.9% sequence similarity), Lysinibacillus fusiformis (97.4% sequence similarity), and Lysinibacillus xylanilyticus (97.3% sequence similarity). However, low levels of DNA-DNA relatedness values suggested that the isolate was distinct from the other closest Lysinibacillus species. Additionally, based on analysis of morphological, physiological, and biochemical characteristics, the isolate could be differentiated from the closest known relatives. Therefore, based on polyphasic taxonomic data, the novel isolate likely represents a novel species, for which the name Lysinibacillus tabacifolii sp. nov. and the type strain K3514(T) (=KCTC 33042(T) =CCTCC AB 2012050(T)) are proposed.


Asunto(s)
Bacillaceae/genética , Nicotiana/microbiología , Hojas de la Planta/microbiología , Bacillaceae/clasificación , Genes de ARNr/genética , Filogenia
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 27(4): 413-6, 2009 Aug.
Artículo en Zh | MEDLINE | ID: mdl-19769262

RESUMEN

OBJECTIVE: Ceramic brackets debonding by Nd:YAG laser is based on the thermal effect of laser, which may cause injury of the pulp tissue. In this study, the histological changes of pulp tissue that subjected to Nd: YAG laser irradiation with different power and time were observed. METHODS: 20 New Zealand rabbits were included in this study. Ceramic brackets were bonded to the 4 incisors as routine. The ceramic brackets of left upper teeth that debonded mechanically were used as control group, while the brackets of right upper, left lower and right lower incisors were debonded by laser with 3 W 3 s (group A), 2 W 5 s (group B) and 5 W 2 s (group C) energies, respectively. The teeth were pulled out at 5 minutes, 1 day, 3 days, 1 week and 1 month after the debonding operations. Slides prepared from the pulp tissues of the debonded teeth were used to evaluate the injury of laser. RESULTS: In comparison with the control group, pulp tissue of teeth that exposed to laser with different energy for 5 minutes showed mild capillary dilation. One day later, group A, B and C showed moderate capillary dilation, and group C also showed moderate infiltration. At 3 days, inflammation was disappeared in group B, whereas capillary dilation was found in group A. Hemorrhage and inflammation cells infiltration were found in group C. At 1 week, alleviation of capillary dilation was found in group A but not in group C. One month later, inflammation disappeared in group A, while pulp tissue in group C showed mild edema and capillary dilation. CONCLUSION: Nd:YAG laser of high energy may cause injury of the pulp tissue during debonding. Laser energy of 3 W 3 s could effectively debond ceramic brackets without irreversible pulp injury.


Asunto(s)
Cerámica , Desconsolidación Dental , Animales , Pulpa Dental , Rayos Láser , Láseres de Estado Sólido , Soportes Ortodóncicos , Conejos
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