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1.
Fish Shellfish Immunol ; 70: 609-620, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28939530

RESUMEN

The current study explored the protective effect of leucine on antioxidant status, apoptosis and tight junction damage in the gill of grass carp (Ctenopharyngodon idella Val.). The trial was conducted by feeding grass carp with six graded level of leucine (7.1, 8.9, 11.0, 13.3, 15.2 and 17.1 g kg-1 diet) for 8 weeks. The fish were fed to apparent satiation 4 times per day. The results indicated that compared with the leucine deficiency group, 8.9-11.3 g leucine kg-1 diet supplementations decreased protein carbonyl (PC), malondialdehyde (MDA) and ROS contents, which may be partially attributed to the improvement of antioxidant status in the gill by increasing hydroxyl radical capacity and anti-superoxide radicals, glutathione contents and the activities and mRNA levels of Cu/Zn superoxide dismutase (SOD1), glutathione peroxidase (GPx), catalase (CAT), glutathione-S-transferase (GST) and glutathione reductase (GR), that referring to the up-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression. Moreover, leucine deficiency induced DNA fragmentation via the up-regulation of caspase-3, caspase-8 and caspase-9 expressions and down-regulation of target of rapamycin and ribosomal S6 protein kinase 1 expressions. Furthermore, leucine deficiency increased interleukin-1ß (IL-1ß), interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α) mRNA expression and decreased IL-10 and transforming growth factor ß (TGF-ß), which was partly related to nuclear factor κB (NF-κB) and its inhibitor (IκB). In contrast, the relative mRNA expression of IL-1, IL-8 and TNF-α was down-regulated with 8.9-11.3 g leucine kg-1 diet supplementations. Finally, the relative mRNA expression of tight junction protein, including occludin, zonula occludens-1, claudin b, claudin 3 and claudin 12 was up-regulated with leucine diet supplementations. Our results indicate that leucine protected the fish gill structural integrity partially because of the inhibition of apoptosis, the improvement of antioxidant status, the regulation of tight junction protein and related signalling molecules mRNA expressions in the fish gill.


Asunto(s)
Apoptosis , Carpas/inmunología , Inmunidad Innata , Leucina/deficiencia , Estrés Oxidativo , Proteínas de Uniones Estrechas/genética , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Carpas/genética , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Branquias/inmunología , Branquias/patología , Leucina/administración & dosificación , Leucina/metabolismo , Distribución Aleatoria , Proteínas de Uniones Estrechas/metabolismo
2.
BMC Cardiovasc Disord ; 17(1): 285, 2017 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-29202750

RESUMEN

BACKGROUND: To investigate the diagnostic value of dual-source computed tomography (DSCT) in the evaluation of tetralogy of Fallot (TOF)-associated extracardiac vascular abnormalities in pediatric patients compared with transthoracic echocardiography (TTE). METHODS: One hundred and twenty-three pediatric patients diagnosed with TOF were included in this retrospective study. All patients underwent DSCT and TTE preoperatively. All associated extracardiac vascular abnormalities and their percentages were recorded. The diagnostic performances of DSCT and TTE were compared based on the surgical results. The image quality of DSCT was rated, and the effective radiation dose (ED) was calculated. RESULTS: A total of 159 associated extracardiac vascular deformities were confirmed by surgery. Patent ductus arteriosus (36, 22.64%), right-sided aortic arch (29, 18.24%), and pulmonary valve stenosis (23, 14.47%) were the most common associated extracardiac vascular abnormalities. DSCT was superior to TTE in demonstrating associated extracardiac anomalies (diagnostic accuracy: 99.13% vs. 97.39%; sensitivity: 92.45% vs. 77.07%; specificity: 99.81% vs. 99.42%). The agreement on grading the image quality of DSCT was excellent (κ = 0.80), and the mean score of the image quality was 3.39 ± 0.50. The mean ED of DSCT was 0.86 ± 0.47 mSv. CONCLUSIONS: Compared to TTE, low-dose DSCT has high diagnostic accuracy in the depiction of associated extracardiac vascular anomalies in pediatric patients with TOF, and could provide more morphological details for surgeons.


Asunto(s)
Ecocardiografía , Dosis de Radiación , Tetralogía de Fallot/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Malformaciones Vasculares/diagnóstico por imagen , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Valor Predictivo de las Pruebas , Exposición a la Radiación/efectos adversos , Exposición a la Radiación/prevención & control , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X/efectos adversos
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(12): 1231-5, 2014 Dec.
Artículo en Zh | MEDLINE | ID: mdl-25523571

RESUMEN

OBJECTIVE: To study the clinical characteristics of childhood Henoch-Schonlein purpura (HSP) on the Tibetan Plateau, China. METHODS: One hundred and twenty-five HSP children admitted to Shannan People's Hospital, Tibet, were assigned to the observation group, and 96 HSP children admitted to Wuhan Children's Hospital were assigned to the control group. The disease characteristics, clinical manifestations, treatment, and prognosis in both groups were retrospectively analyzed and compared. RESULTS: The mean age of HSP onset and the female-to-male ratio in the observation group were both significantly higher than in the control group (P<0.05). There was a significant difference in seasonal onset between two groups. Significant differences in the etiological factors were observed between the two groups (P<0.05). The gastrointestinal manifestation was more prominent in the observation group compared with that in the control group (P<0.05). Laboratory findings showed that the mean erythrocyte sedimentation rate, counts of white blood cells and platelets, and percentage of neutrophil leucocytes were significantly lower, while the hemoglobin level was significantly higher in the observation group than in the control group (P<0.05). A total of 124 HSP patients (99.2%) in the observation group had a full recovery or improvement, and the overall cure rate and improvement rate showed no significant differences between two groups (P>0.05). Only 2.4% of the patients (3 cases) in the observation group had recurrent attack during follow-up, which was significantly lower than that in the control group (16.7%; P<0.05). CONCLUSIONS: Childhood HSP on the Tibetan Plateau shows partial differences in disease characteristics, clinical manifestations, and laboratory measurements compared with that in the plain area. The overall prognosis is better and the recurrent rate is lower among HSP children on the Tibetan Plateau.


Asunto(s)
Vasculitis por IgA/tratamiento farmacológico , Adolescente , Niño , Preescolar , Femenino , Humanos , Vasculitis por IgA/diagnóstico , Vasculitis por IgA/etiología , Masculino , Pronóstico , Tibet
4.
Commun Biol ; 7(1): 583, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755265

RESUMEN

Tumor-associated macrophages of the M2 phenotype promote cancer initiation and progression. Importantly, M2 macrophage-derived exosomes play key roles in the malignancy of cancer cells. Here, we report that circTMCO3 is upregulated in ovarian cancer patients, and its high expression indicates poor survival. M2-derived exosomes promote proliferation, migration, and invasion in ovarian cancer, but these effects are abolished by knockdown of circTMCO3. Furthermore, circTMCO3 functions as a competing endogenous RNA for miR-515-5p to reduce its abundance, thus upregulating ITGA8 in ovarian cancer. miR-515-5p inhibits ovarian cancer malignancy via directly downregulating ITGA8. The decreased oncogenic activity of circTMCO3-silencing exosomes is reversed by miR-515-5p knockdown or ITGA8 overexpression. Exosomal circTMCO3 promotes ovarian cancer progression in nude mice. Thus, M2 macrophage-derived exosomes promote malignancy by delivering circTMCO3 and targeting the miR-515-5p/ITGA8 axis in ovarian cancer. Our findings not only provide mechanistic insights into ovarian cancer progression, but also suggest potential therapeutic targets.


Asunto(s)
Exosomas , Ratones Desnudos , MicroARNs , Neoplasias Ováricas , Femenino , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Neoplasias Ováricas/metabolismo , Humanos , Exosomas/metabolismo , Exosomas/genética , MicroARNs/genética , MicroARNs/metabolismo , Animales , Ratones , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Macrófagos/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Proliferación Celular , Cadenas alfa de Integrinas/genética , Cadenas alfa de Integrinas/metabolismo , Movimiento Celular
5.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 32(12): 1632-7, 2012 Dec.
Artículo en Zh | MEDLINE | ID: mdl-23469602

RESUMEN

OBJECTIVE: To observe the clinical effects of Linda Mixture (LM) on cholestatic liver diseases caused by cytomegalovirus (CMV) infection. METHODS: Totally 240 CMV infected cholestatic liver diseases infants, who were hospitalized at the Department of Integrated Traditional Chinese and Western Medicine, Wuhan Children's Hospital from January 2008 to June 2011, were randomly assigned to the treatment group (120 cases) and the control group (120 cases). Patients in the treatment group were treated by LM combined ganciclovir, while those in the control group were treated by ganciclovir alone. The therapeutic course was 2 months. The patients were assigned to 3 sub-groups according to the quantification standards of symptoms and signs, i. e., the No. 1 treatment group (mild, 30 cases), the No. 1 control group (mild, 30 cases), the No. 2 treatment group (moderate, 30 cases), the No. 2 control group (moderate, 30 cases), the No. 3 treatment group (severe, 30 cases), the No. 1 control group (severe, 30 cases). The clinically cured rate and the total effective rate, the jaundice subside time, the retraction time for Gan and Pi, the body weight growth, the indices of the liver function, and lab indices of CMV infection were observed before and after treatment. RESULTS: After treatment the cured rate was 77.50% and the total effective rate was 88.33% in the treatment group, while they were 60.83% and 76.67% in the control group. There was statistical difference between the two group (P<0.05, P<0.01). There was some improvement in the jaundice subside time, the retraction time for Gan and Pi, the body weight growth, the indices of the liver function in the two groups. Better results were obtained in the treatment group than in the control group, showing statistical difference (P<0.05, P<0.01). The lab indices of CMV infection showed negative to some degrees. The negative rates of serum IgM (83.54% in the treatment group and 63. 64% in the control group) and the serum CMVDNA (84.52% in the treatment group and 67.47% in the control group) were better in the treatment group than in the control group, showing statistical difference (P<0.01). There was no obvious difference in the negative rate of CMV antigen in urine between the two groups (P>0.05). CONCLUSIONS: LM combined ganciclovir therapy showed definite effects in treating cholestatic liver diseases caused by CMV infection. Early treatment for severe infants might change their prognosis. LM also could alleviate adverse reactions during the therapeutic course.


Asunto(s)
Colestasis/tratamiento farmacológico , Infecciones por Citomegalovirus/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Hepatopatías/tratamiento farmacológico , Fitoterapia , Colestasis/complicaciones , Colestasis/virología , Femenino , Ganciclovir/uso terapéutico , Humanos , Lactante , Hepatopatías/etiología , Hepatopatías/virología , Masculino
6.
Travel Med Infect Dis ; 39: 101950, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33307197

RESUMEN

BACKGROUND: To investigate and compare the clinical and imaging features among family members infected with COVID-19. METHODS: We retrospectively collected a total of 34 COVID-19 cases (15 male, 19 female, aged 48 ± 16 years, ranging from 10 to 81 years) from 13 families from January 17, 2020 through February 15, 2020. Patients were divided into two groups: Group 1 - part of the family members (first-generation) who had exposure history and others (second-generation) infected through them, and Group 2 - patients from the same family having identical exposure history. We collected clinical symptoms, laboratory findings, and high-resolution computed tomography (HRCT) features for each patient. Comparison tests were performed between the first- and second-generation patients in Group 1. RESULTS: In total there were 21 patients in Group 1 and 20 patients in Group 2. For Group 1, first-generation patients had significantly higher white blood cell count (6.5 × 109/L (interquartile range (IQR): 4.9-9.2 × 109/L) vs 4.5 × 109/L (IQR: 3.7-5.3 × 109/L); P = 0.0265), higher neutrophil count (4.9 × 109/L (IQR: 3.6-7.3 × 109/L) vs 2.9 × 109/L (IQR: 2.1-3.3 × 109/L); P = 0.0111), and higher severity scores on HRCT (3.9 ± 2.4 vs 2.0 ± 1.3, P = 0.0362) than the second-generation patients. Associated underlying diseases (odds ratio, 8.0, 95% confidence interval: 3.4-18.7, P = 0.0013) were significantly correlated with radiologic severity scores in second-generation patients. CONCLUSION: Analysis of the family cluster cases suggests that COVID-19 had no age or sex predominance. Secondarily infected patients in a family tended to develop milder illness, but this was not true for those with existing comorbidities.


Asunto(s)
COVID-19/patología , Familia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/transmisión , Niño , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , SARS-CoV-2 , Adulto Joven
7.
Abdom Imaging ; 33(6): 689-94, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18180983

RESUMEN

BACKGROUND: Findings of adrenal tuberculosis with MR scanning have never been reported in the literature. The aim of this study was to determine MR characteristics for tuberculous Addison's disease, and evaluate the utility of MR imaging as a useful diagnosis tool of the entity. PATIENTS AND METHODS: Eighteen patients with proven adrenal tuberculosis were included. All patients had conventional T(1)- and T(2)-weighted image. Among the 18 patients, contrast-enhanced T(1)WI had been done in 10. MR manifestations were retrospectively evaluated blindly for the location, contour, signal intensity, and enhancement patterns. RESULTS: All patients clinically exhibited hyperpigmentation and lethargy. Physical examination revealed weight loss, signs of dehydration, and hypotension. Biochemical investigation confirmed adrenal insufficiency. The adrenal glands were affected bilaterally in 16 patients (89%) and unilaterally in 2 patients (11%). Thirty-three glands were enlarged (97%), while one was atrophic (3%). Of the 33 enlarged glands, 20 (61%) were mass-like and 13 (39%) had preserved contours. The central region of the enlarged glands demonstrated T(2) hypo- or iso-SI in 21 (62%) and T(2) hyper-SI in 12 (38%). Among the 18 enlarged glands that had contrast MR, 15 (83%) had peripheral rim enhancement, 1 (6%) had homogeneous enhancement, and the last two (11%) had heterogeneous enhancement. CONCLUSION: MR characteristics can reveal certain pathological changes of adrenal tuberculosis, and MR imaging could be recommended as the imaging modality for the diagnosis of the entity.


Asunto(s)
Enfermedad de Addison/etiología , Imagen por Resonancia Magnética/métodos , Tuberculosis Endocrina/complicaciones , Tuberculosis Endocrina/diagnóstico , Enfermedad de Addison/diagnóstico , Glándulas Suprarrenales/patología , Adulto , Anciano , Medios de Contraste , Diagnóstico Diferencial , Femenino , Gadolinio DTPA , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Retrospectivos
8.
Eur J Radiol ; 62(3): 352-8, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17466476

RESUMEN

OBJECTIVE: To determine the characteristics of tuberculous Addison's disease on the axial and multiplanar reformatted (MPR) images of the multidetector-row computed tomography (MDCT). MATERIALS AND METHODS: The unenhanced and contrast-enhanced MDCT features in 19 patients with tuberculous Addison's disease were retrospectively assessed for the location, contour, size, calcification, attenuation, and enhancement patterns. The correlation between the duration of Addison's disease and the percentage of calcification presence was evaluated. RESULTS: The adrenal glands were infected bilaterally in all of the 19 cases (100%, 38 glands). Enlargement of the glands appeared in 18 cases (94.7%, 36 glands) and the remaining one case (5.3%, two glands) showed atrophy bilaterally. Of the 36 enlarged adrenals, 13 (36.1%) had preserved contours, and the other 23 (63.9%) were mass-like. The size of the adrenals ranged from 0.6 to 4.8 cm (mean 1.92+/-0.96 cm). Calcification was revealed in 16 adrenals (16/38, 42.1%), increasing in incidence with disease progression. Fourteen of the 36 (38.9%) enlarged adrenals showed peripheral enhancement while the remaining 22 (61.1%) demonstrated heterogeneous enhancement. The DeltaCT value, the attenuation measurement of mass-like lesions, was less in the central area (7+/-4 HU) than that in the peripheral area (32+/-14 HU) (P<0.01) between the unenhanced and contrast-enhanced scan. CONCLUSION: MDCT can reveal the characteristic morphology and CT attenuation in the tuberculous Addison's disease. Combined with its clinical presentations and biochemical findings, we can diagnose and stage adrenal tuberculosis with high specificity and accuracy on MDCT.


Asunto(s)
Enfermedad de Addison/diagnóstico , Glándulas Suprarrenales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Tuberculosis Endocrina/diagnóstico , Enfermedad de Addison/etiología , Enfermedad de Addison/patología , Glándulas Suprarrenales/patología , Adulto , Anciano , Calcinosis/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Diagnóstico Diferencial , Diatrizoato , Progresión de la Enfermedad , Femenino , Humanos , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/instrumentación , Tuberculosis Endocrina/complicaciones
9.
Eur J Radiol ; 62(3): 359-70, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17532488

RESUMEN

Adrenal glands are common sites of diseases. With dramatically increased use of computed tomography (CT) and magnetic resonance (MR) imaging, more and more uncommon adrenal masses have been detected incidentally at abdominal examinations performed for other purposes. In this article, uncommon adrenal masses are classified as cystic masses (endothelial cysts, epithelial cysts, parasitic cysts, and pseudocysts), solid masses (ganglioneuroma, ganglioneuroblastoma, extramedullary plasmacytoma (EMP), neurilemmoma, and lymphoma), fat-containing masses (myelolipoma, teratoma), and infectious masses (tuberculoma), and the imaging features of these uncommon masses are demonstrated. Although most of these lesions do not have specific imaging features, some fat-containing masses and cystic lesions present with characteristic appearances, such as myelolipoma, teratoma, and hydatid. Combination with histopathologic characteristic of these uncommon masses of adrenal gland, radiological features of these lesions on CT and MR imaging can be accurately understood with more confidences. Moreover, CT and MRI are highly accurate in localization of uncommon adrenal masses, and useful to guide surgical treatments.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico , Linfoma/diagnóstico , Imagen por Resonancia Magnética/métodos , Mielolipoma/diagnóstico , Neoplasias de Células Germinales y Embrionarias/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Glándulas Suprarrenales/diagnóstico por imagen , Glándulas Suprarrenales/patología , Glándulas Suprarrenales/ultraestructura , Quistes/diagnóstico , Humanos , Hallazgos Incidentales , Enfermedades Raras , Tuberculoma/diagnóstico
10.
Eur J Radiol ; 62(1): 126-31, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17182208

RESUMEN

PURPOSE: To describe CT morphology of untreated adrenal tuberculosis during the different stages of the natural history of the disease and to evaluate the diagnostic implications of CT features. MATERIALS AND METHODS: We retrospectively evaluated CT features in 42 patients with documented adrenal tuberculosis for the location, size, morphology, and enhancement patterns shown on CT images. The clinical duration were correlated with the CT features. RESULTS: Of the 42 patients with untreated adrenal tuberculosis, bilaterally enlarged adrenal glands were revealed in 38 cases (91%), unilaterally enlarged in 3 cases (7%), and normal size in 1 case (2%). Of the 41 cases (98%) with enlargement, mass-like enlargement was seen in 20 cases (49%) and enlargement with preserved contours in 21 cases (51%). Peripheral rim enhancement presented in 22 cases (52%) on contrast-enhanced CT. Non-enhanced CT scan revealed calcification in 21 cases (50%). As the duration of Addison's disease increased, the presence of calcification and contour preservation increased concomitantly (p<0.001), whereas peripheral rim enhancement and mass-like enlargement decreased concomitantly on CT images (p<0.001). CONCLUSION: CT may be helpful in diagnosing adrenal tuberculosis when clinically suspected, and CT features are correlated to the clinical duration of Addison's disease.


Asunto(s)
Enfermedad de Addison/diagnóstico por imagen , Enfermedad de Addison/microbiología , Enfermedades de las Glándulas Suprarrenales/complicaciones , Enfermedades de las Glándulas Suprarrenales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Tuberculosis Endocrina/complicaciones , Tuberculosis Endocrina/diagnóstico por imagen , Adulto , Anciano , Medios de Contraste , Humanos , Yohexol/análogos & derivados , Modelos Lineales , Persona de Mediana Edad , Reproducibilidad de los Resultados
11.
Zhong Yao Cai ; 30(4): 401-3, 2007 Apr.
Artículo en Zh | MEDLINE | ID: mdl-17674787

RESUMEN

OBJECTIVE: To provide the scientific basis for identification and utilization of Memorialis hirta ( BL) Wedd. METHODS: Macroscopical identification and microscopic identification. RESULTS: To make system pharmacognostical studies on stalk and fine powder of Memorialis hirta (BL) Wedd. CONCLUSION: These characteristic can provide the scientific basis for identification of Memorialis hirta (BL) Wedd.


Asunto(s)
Tallos de la Planta/anatomía & histología , Plantas Medicinales/anatomía & histología , Urticaceae/anatomía & histología , Medicamentos Herbarios Chinos/aislamiento & purificación , Farmacognosia/métodos , Tallos de la Planta/citología , Plantas Medicinales/citología , Polvos , Urticaceae/citología
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(7): 979-83, 2016 Jun 20.
Artículo en Zh | MEDLINE | ID: mdl-27435780

RESUMEN

OBJECTIVE: To explore a new method for finite element modeling to achieve material property assignment based on in situ CT gray value in simulated osteotomies for deformities. METHODS: A CT scan dataset of the lower limb of a patient with extorsion deformity was obtained for three-dimensional reconstruction using Mimics software and preparing a solid model. In the CAD software, the parameters for osteotomy simulation were defined including the navigation axis, rotation angle and reference plane. The tibia model was imported to the FEA pre-processing software for meshing procedure and then exported to Mimics. All the segments of the tibia meshed model were assigned uneven material properties based on the relationship between CT gray values and material properties in the Mimics software. Finally, all the segments of the tibia model, reference axis and reference plane were assembled in the pre-processing software to form a full finite element model of a corrected tibia, which was submitted to resolver for biomechanical analysis. RESULTS: The tibia model established using our modeling method had inhomogeneous material properties based on CT gray values, and was available for finite element analysis for the simulation of osteotomy. CONCLUSIONS: The proposed finite element modeling method, which retains the accuracy of the material property assignment based on CT gray value, can solve the reposition problem commonly seen in modeling via the routine method of property assignment and provides an efficient, flexible and accurate computational biomechanical analysis method for orthopedic surgery.


Asunto(s)
Análisis de Elementos Finitos , Osteotomía , Tibia/patología , Tomografía Computarizada por Rayos X , Humanos , Modelos Anatómicos , Programas Informáticos
13.
Huan Jing Ke Xue ; 31(7): 1689-94, 2010 Jul.
Artículo en Zh | MEDLINE | ID: mdl-20825047

RESUMEN

The diffusion mechanism of acetylene,which can inhibit the activity of methanogens, was studied. Paraffin wax and rosin were used as matrix of slow-release and calcium carbide was used as inhibition material. Based on the T. Higuchi equation and the characteristics of slow-release inhibitors, a mechanism model was derived. Moreover, the effective diffusion coefficients (De) can be acquired by this model. During the diffusion process, the reaction heat of calcium carbide and water could make acetylene gas expansion and caused the slow-release inhibitors expansion if the hardness of the slow-release inhibitors is inadequate. The hardness and compactness were enhanced and the effective diffusion coefficients reached 2.2849 x 10(-8) cm2/min (R2 = 0.9901) when the mass faction of rosin was 20% and the mass ratio of matrix to calcium carbide was 1/1. Hence,the mitigation the methane generation with municipal solid waste (MSW) can be achieved by the technology of slow-release inhibition.


Asunto(s)
Acetileno/análogos & derivados , Acetileno/química , Contaminantes Atmosféricos/antagonistas & inhibidores , Metano/antagonistas & inhibidores , Metano/aislamiento & purificación , Contaminantes Atmosféricos/aislamiento & purificación , Difusión , Restauración y Remediación Ambiental , Cinética , Modelos Químicos , Vaselina/química , Resinas de Plantas/química , Factores de Tiempo
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