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1.
Chinese Journal of Radiological Health ; (6): 58-61, 2023.
Article Dans Chinois | WPRIM | ID: wpr-965373

Résumé

@#With the utilization of more types of radiation with a wider energy range, the application scope of the currently valid operational quantities is limited due to some conceptual defects, so a new group of operational quantities was proposed recently by the International Commission on Radiation Units and Measurements. The unification of protection quantities and operational ones is achieved in conceptual and physical sense. However, to achieve the comprehensive application of these new operational quantities in China, such preliminary work should be done as computational model construction and built-in of a calibration system in monitoring equipment, which depends on the collaborative development of multi-parties.

2.
Chinese Journal of Radiological Health ; (6): 631-634, 2022.
Article Dans Chinois | WPRIM | ID: wpr-965693

Résumé

@#Operational quantities, which are used to estimate protection quantities in the field of radiation protection, are important in area monitoring. The current operational quantities show certain limitations as the particle types and energy ranges are expanded. The International Commission on Radiation Units and Measurements Report 95 proposed a new system of operational quantities, where the definitions and phantoms of the operational quantities are consistent with the protection quantities, enabling better estimation of the protection quantities over wider ranges of particle types and energies. This paper focuses on the effects of the new recommended operational quantity system in area monitoring from the aspects of phantom application, conversion coefficient updating, and monitor design and calibration.

3.
Chinese Journal of Radiological Medicine and Protection ; (12): 150-154, 2022.
Article Dans Chinois | WPRIM | ID: wpr-932577

Résumé

A set of new operational quantities for external radiation protection was proposed in ICRU Report 95. The new operational quantities were designed to overcome the conceptual and technical shortcomings of the existing operational quantities, and to achieve a better estimation of the protection quantities. This paper introduces the development of operational quantities, and the changes in their definitions, calculation phantoms and the application scopes, so as to fully understand the significance of the changes in the new operational quantities, which can be used as a reference for the relevant professionals.

4.
Chinese Journal of Hospital Administration ; (12): 827-830, 2021.
Article Dans Chinois | WPRIM | ID: wpr-934513

Résumé

Centralized drug procurement in large quantities is a major step to deepen the medical and healthcare system reform, to improve the mechanism of drug price formation, and to give full play to the role of medical insurance in guiding drug prices in China. Combined with the practice of centralized drug purchasing in public hospitals, the authors sorted out the practical problems and causes from four aspects which affected the implementation of centralized drug purchasing policy in public hospitals: selection on centrally purchased drugs, procurement and supply, clinical use, and hospital financial operation. On this basis, suggestions were put forward to provide reference for the normalization of centralized drug procurement work, such as coordinating national and regional drug collection policies, reasonably setting distribution costs, extending the agreed procurement period, and carrying out special evaluation for drug collection.

5.
Rev. colomb. ciencias quim. farm ; 48(3): 528-546, sep.-dic. 2019. tab, graf
Article Dans Anglais | LILACS-Express | LILACS | ID: biblio-1138769

Résumé

SUMMARY The solubilities of celecoxib (CLX), a COX-2 selective nonsteroidal anti-inflammatory drug, were determined in water-ethanol and ethanol-ethyl acetate mixtures at several temperatures (288.15-308.15 K). The solubility curves as a function of ethanol ratio were studied at five temperatures, they showed a single maximum located at 50% ethanol-ethyl acetate (δ1 = 22.50 MPa1/2). The measurements of the variation of inherent drug solubility with temperature were used to estimate different thermodynamic parameters, enthalpy, entropy and Gibbs free energy of solution (ΔH S , ΔS S and ΔG S hm , respectively). The apparent enthalpies of the solution were a nonlinear function of the ethanol ratio in aqueous mixture. Non-linear enthalpy-entropy compensation analysis was observed indicating different dissolution mechanism with the variation in mixtures composition. The solubility enhancement is entropy driven at water-rich region (0-40% v/v ethanol) and enthalpy controlled at ethanol-rich region (40-100% v/v ethanol), likely due to water-structure loss around nonpolar moieties of the drug and for the ethanol-rich mixtures it is the enthalpy, probably due to the drug better solvation.


RESUMEN Se determinó la solubilidad del celecoxib (CLX), un fármaco antiinflamatorio no esteroide selectivo de COX-2, en agua-etanol y etanol-acetato de etilo a varias temperaturas (288,15-308,15 K). Los perfiles de solubilidad obtenidos fueron estudiados en función de la proporción de etanol en las cinco temperaturas de estudio. Los resultados muestran solamente un máximo en el 50% de etanol-acetato de etilo (δ1 = 22,50 MPa1/2). La variación de la solubilidad con la temperatura se utilizó para calcular diferentes parámetros termodinámicos, entalpia, entropía y energía de disolución libre de Gibbs (ΔH3, ΔS S y ΔGS hm, respectivamente). Las entalpias aparentes de disolución fueron no lineales en la mezcla acuosa. Además, se observó un análisis de compensación de entalpía-entropía no lineal, lo que indica un mecanismo de disolución que varía con la composición de cada mezcla. El aumento de la solubilidad es impulsado por la entropía en la región rica en agua (0-40% v/v de etanol) y la entalpía en la región rica en etanol (40-100% v/v de etanol), probablemente debido a la pérdida de la estructura del agua alrededor de los residuos no polares del fármaco y para las mezclas ricas en etanol es la entalpía, probablemente debido a la mejor solvatación del fármaco.

6.
Journal of Sun Yat-sen University(Medical Sciences) ; (6): 747-753, 2019.
Article Dans Chinois | WPRIM | ID: wpr-817758

Résumé

@#【Objective】To study retrospectively the serum hepatitis B surface antigen(HBsAg)and HBsAg normal⁃ ized to the same hepatic parenchyma cell volume(HPCV),namely,the same hepatic cell quantities,between HBeAg- positive and HBeAg-negative chronic hepatitis B(CHB).【Methods】A total of 168 CHB patients who had undergone liv⁃ er biopsy and test of serum HBsAg levels due to their disease in the Third Affiliated Hospital of SunYat-sen University were selected as the study subjects. The serum HBsAg levels,as well as HBsAg levels normalized to HPCV(hepatic cell quantities)were compared between HBeAg-positive and HBeAg-negative CHB,respectively.【Results】There was statis⁃ tically significant difference in serum HBsAg levels between HBeAg-positive and HBeAg-negative CHB(P = 0.028), while there was no statistical difference in HBsAg normalized to HPCV(P = 0.073). There were no correlations between serum HBsAg and liver inflammation grades(HBeAg-positive:r s = 0.020,P = 0.876 & HBeAg-negative:r s = 0.037,P =0.711). Similarly,there were no correlations between HBsAg and hepatic fibrosis stages(HBeAg-positive:r s = 0.087, P = 0.488 & HBeAg-negative:r s = 0.144,P = 0.148). Nevertheless,statistically significant positive correlations were shown between HBsAg normalized to HPCV and liver inflammation grades(HBeAg-positive:r s = 0.309,P = 0.012 & HBeAg-negative:r s = 0.389,P < 0.001). Similarly,the HBsAg normalized to HPCV and hepatic fibrosis stages were shown to be statistically significantly correlated(HBeAg-positive:r s = 0.490,P < 0.001 & HBeAg-negative:r s = 0.599, P < 0.001).【Conclusions】Serum HBsAg normalized to HPCV but not HBsAg levels,is correlated with liver inflamma⁃ tion grades as well as hepatic fibrosis stages positively in both HBeAg-positive and HBeAg-negative CHB. But there is no difference in serum HBsAg levels normalized to HPCV between HBeAg-positive and HBeAg-negative CHB.

7.
Rev. chil. radiol ; 24(1): 5-11, mar. 2018. tab
Article Dans Espagnol | LILACS | ID: biblio-959567

Résumé

Resumen:Existen diversos documentos y recomendaciones internacionales sobre nombres, conceptos, definiciones y campos de aplicación para diversas magnitudes y unidades utilizadas para monitorear los niveles de radiación ionizante a los que son expuestos los trabajadores durante los procedimientos de Radiodiagnóstico e Intervencionismo. Sin embargo, la legislación nacional, al igual que para la dosimetría de los pacientes, no se encuentra actualizada en este sentido y no contempla en sus documentos un glosario actualizado que permita encontrar en forma rápida y precisa este tipo de información. Por lo anterior, este trabajo de revisión corresponde a un segundo documento guía, complementario a nuestro trabajo publicado en 2015 titulado "Magnitudes y unidades para dosimetría a pacientes en radiodiagnóstico e intervencionismo", que describe de manera didáctica y en un lenguaje sencillo para los profesionales de la salud y áreas afines, las principales magnitudes y unidades que se deben conocer y utilizar en la dosimetría ocupacional de los trabajadores que participan en procedimientos de Radiodiagnóstico e Intervencionismo.


Abstract: There are many documents and international recommendations offer names, concepts, definitions and fields of application for various quantities and units used to monitor the exposure levels of ionising radiation to which workers are exposed during the diagnostic and interventional radiology procedures. However, as in the case of patient dosimetry, national legislation is not up-to-date in this area and nowhere does it establish an up-to-date glossary that would facilitate rapid and precise location of this kind of information. In light of the foregoing, this review paper presents a second guidance document, complementary to our published article in 2015 titled "Quantities and units used in patient dosimetry in radiodiagnostic and intervencional procedures", which describes the principal quantities and units that must be known and used in occupational dosimetry for workers participating in diagnostic and interventional radiology procedures, in a didactical manner and using simple language for professionals in health and similar areas.


Sujets)
Humains , Radioprotection/normes , Personnel de santé , Dosimétrie/méthodes , Exposition aux rayonnements/prévention et contrôle , Exposition professionnelle
8.
Chinese Journal of Information on Traditional Chinese Medicine ; (12): 50-53, 2017.
Article Dans Chinois | WPRIM | ID: wpr-511464

Résumé

Objective To observe the effects of different quantities of cake-separated moxibustion on blood cells and immunoglobulin in immunosuppressive rabbits; To study the possible mechanism of quantity-effect difference. Methods Immunosuppressive rabbit model was established by intraperitoneal injection of cyclophosphamide. Rabbits were randomly divided into blank group, model group, cake-separated moxibustion 3 Zhuang group, 5 Zhuang group, 7 Zhuang group.Liuwei Dihuang Decoction was used to make herbal-cake, and was put on Shenque (RN8), Guanyuan (RN4), and other acupoints, once for every other day, 10 times in total. Venous blood was taken on the next day after finishing treatment, and the contents of blood cells series and IgG, IgM, complement C3 and complement C4 were detected.Results Compared with blank group, the levels of WBC, NEU, RBC, HGB, HCT, PLT, IgG, IgM, and complement C3 of model group significantly decreased, while the levels of LYM and MONO significantly increased (P<0.01). Compared with model group, the increase of HCT and IgM in the cake-separated moxibustion 3 Zhuang group was not significant, the levels of WBC, NEU, RBC, HGB, HCT, PLT, IgG, IgM, and complement C3 in all treatment groups significantly increased, and LYM and MONO significantly decreased (P<0.01). Compared with cake-separated moxibustion 3 Zhuang group, the levels of WBC, IgG, and complement C3 of cake-separated moxibustion 5 Zhuang group significantly increased, and the levels of WBC, HGB and complement C3 of cake-separated moxibustion 7 Zhuang group significantly increased (P<0.01).Conclusion Cake-separated moxibustion can improve the immune function under immunosuppressive state induced by cyclophosphamide, and different quantities have differences in efficacy.

9.
Rev. chil. radiol ; 21(3): 94-99, 2015. ilus, tab
Article Dans Espagnol | LILACS | ID: lil-771668

Résumé

Because diagnostic and interventional radiology procedures represent one of the main sources of irradiation by ionizing radiation in the population, it has become a priority to become familiar with the quantities and units that account for patient dosimetry. There are countless documents and international recommendations on names, concepts, definitions and areas of application for various quantities and units used in patient dosimetry, in interventional and diagnostic radiology procedures. However, national legislation is not updated in this regard and does not provide, in any of its documents, an updated glossary that enables finding this type of information quickly and precisely. Therefore, this review paper presents in a didactic way and in plain language, the main quantities and units to be used in the dosimetry of patients undergoing diagnostic and interventional radiology procedures.


Debido a que los procedimientos de radiodiagnóstico e intervencionismo representan una de las principales fuentes de irradiación a la población por radiaciones ionizantes, se vuelve prioritario conocer las magnitudes y unidades que dan cuenta de la dosimetría a los pacientes. Existen innumerables documentos y recomendaciones internacionales sobre nombres, conceptos, definiciones y campos de aplicación para diversas magnitudes y unidades utilizadas en la dosimetría de pacientes en procedimientos de radiodiagnóstico e intervencionismo. Sin embargo, la legislación nacional no se encuentra actualizada en este sentido y no contempla en ninguno de sus documentos, un glosario actualizado que permita encontrar en forma rápida y precisa este tipo de información. Por lo anterior, este trabajo de revisión presenta de manera didáctica y en un lenguaje sencillo, las principales magnitudes y unidades que se deben utilizar en la dosimetría de pacientes sometidos a procedimientos de radiodiagnóstico e intervencionismo.


Sujets)
Humains , Imagerie diagnostique/normes , Kerma , Radiographie interventionnelle/normes , Radiométrie/normes
10.
Radiol. bras ; 47(5): 288-291, Sep-Oct/2014. tab, graf
Article Dans Portugais | LILACS | ID: lil-726338

Résumé

Objetivo: Visando contribuir para o conhecimento das doses em tomografia computadorizada (TC), este trabalho teve o objetivo de quantificar grandezas dosimétricas associadas a exames do abdome em pacientes pediátricos, comparando-as com os níveis de referência em radiodiagnóstico (NRD). Materiais e métodos: O estudo foi realizado em dois hospitais, em um tomógrafo Toshiba Asteion single-slice e um GE BrightSpeed multi-slice. Medidas foram feitas com uma câmara de ionização tipo lápis e um objeto simulador de tronco de polimetilmetacrilato de 16 cm de diâmetro. Resultados: Os valores do índice ponderado de kerma no ar (CW) não apresentaram diferenças significativas, porém, para as grandezas índice de kerma no ar volumétrico (CVOL), produto kerma-comprimento (PKL,CT) e dose efetiva, as diferenças foram relevantes. Conclusão: Apenas o CW apresentou valores menores que os NRD, sugerindo que a otimização não seria necessária. Porém, os valores de PKL,CT e dose efetiva mostraram que há espaço para reduzir as doses de radiação pediátricas. Este trabalho ressalta a importância de avaliar todas as grandezas dosimétricas associadas aos exames por TC. .


Objective: Aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods: The study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results: No significant difference was observed in the values for weighted air kerma index (CW), but the differences were relevant in values for volumetric air kerma index (CVOL), air kerma-length product (PKL,CT) and effective dose. Conclusion: Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, PKL,CT and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. .

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