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1.
The mass childhood immunization programme has traditionally been viewed as a safe and effective preventative measure by health promoters, primary health care professionals and governments. This consensus has meant that immunization has rarely been viewed as ethically problematic. A number of recent changes in the context of the delivery of health care, particularly the emphasis on consumerism and the effect of the marketization of services, makes timely an examination of ethical, social and political issues. This article examines four main grounds for problematizing the mass childhood immunization programme. These are: clinical research evidence about the safety and efficacy of vaccines; the masking of wider social and political determinants of ill health; the contradictory strictures about collective and individual rights in relation to immunization; and the uniqueness of childhood immunization as a physical intrusion into a healthy body. The implications of these ethical issues are discussed in relation to informed consent and the need for a 'greenfield' review that includes the views of dissenting parents, lawyers and moral philosophers, as well as health professionals. 相似文献
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MC Bonhomme KL Grove S Caron CT Crilley G Thibault CF Deschepper R Garcia 《Canadian Metallurgical Quarterly》1998,9(10):1777-1786
The natriuretic peptide receptor (NPR) family consists of three receptor subtypes: two transmembrane forms that contain a guanylyl cyclase intracellular domain (NPR-A and NPR-B), and one truncated form (NPR-C). Because of the lack of specific agonists and antagonists for each receptor subtype and to the difficulty to detect the presence of small quantities of NPR-B by ligand binding studies, polyclonal antibodies against a peptide whose sequence was chosen from a region of the extracellular domain of rat NPR-B that is not homologous to sequences in NPR-A and NPR-C were developed. Western blotting with affinity-purified anti-NPR-B (413-426)-Tyr revealed a polypeptide of approximately 120 kD on COS-1 cell membranes transfected with rat NPR-B cDNA. The antibody recognized a second polypeptide, approximately 5 to 10 kD smaller, which probably represents the unglycosylated receptor. Anti-NPR-B (413-426)-Tyr did not show crossreactivity to any other NPR. Western blotting analysis with anti-NPR-B (413-426)-Tyr also identified a protein of appropriate size in renal vascular membranes. These results were supported by immunohistochemistry findings that demonstrated staining for NPR-B on papillary and medullary capillaries, glomeruli, and renal arteries. This study concludes that NPR-B is present in the rat kidney, although it was only detected in vascular structures. 相似文献
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Matrix metalloproteinases (MMPs) have been detected in forming dental enamel and are thought to play an important role during enamel biomineralization. Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a membrane bound member of the MMP gene family that has previously been shown to be expressed by cells associated with bone and cartilage formation (osteoclasts, osteoblasts and chondrocytes). Thus, we asked if MT1-MMP was also expressed by the cells responsible for the formation of enamel and dentin. A porcine MT1-MMP cDNA composed of 3284 bp was isolated from an enamel organ-specific cDNA library. Multiple tissue Northern blot analysis revealed that the MT1-MMP message was expressed highly in the enamel organ and pulp organ when compared to the expression levels observed in other non-mineralizing tissues. Northern blot analysis of stage-specific enamel organs (early secretory, late secretory, or maturation stage) and their corresponding pulp organs revealed that MT1-MMP expression increased as the dentin matured. In the enamel organs, however, the MT1-MMP message level became reduced only during the late secretory stage. Immunohistochemical analysis showed that MT1-MMP was present on the surface of the cells (ameloblasts and odontoblasts) responsible for dentin and enamel formation. Thus, MT1-MMP is highly expressed in developing tooth tissues and may play a role in the biomineralization of enamel and dentin. 相似文献
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R. Etchart-Salas V. Rat J. F. Coudert P. Fauchais N. Caron K. Wittman S. Alexandre 《Journal of Thermal Spray Technology》2007,16(5-6):857-865
Direct current Suspension Plasma Spraying (SPS) allows depositing finely structured coatings. This article presents an analysis
of the influence of plasma instabilities on the yttria-stabilized suspension drops fragmentation. A particular attention is
paid to the treatment of suspension jet or drops according to the importance of voltage fluctuations (linked to those of the
arc root) and depending on the different spray parameters such as the plasma forming gas mixture composition and mass flow
rate and the suspension momentum. By observing the suspension drops injection with a fast shutter camera and a laser flash
sheet triggered by a defined transient voltage level of the plasma torch, the influence of plasma fluctuations on jet or drops
fragmentation is studied through the deviation and dispersion trajectories of droplets within the plasma jet.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
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Bahoumina Prince Hallil Hamida Lachaud Jean-Luc Rebière Dominique Dejous Corinne Abdelghani Aymen Frigui Kamel Bila Stephane Baillargeat Dominique Zhang Qing Coquet Phillipe Paragua Carlos Pichonat Emmanuelle Happy Henri 《Microsystem Technologies》2022,28(6):1365-1378
Microsystem Technologies - This study presents the results on the feasibility of a resonant planar chemical capacitive sensor in the microwave frequency range suitable for gas detection and... 相似文献
10.
Elena Lopez Adrien Leygue Emmanuelle Abisset-Chavanne Sebastien Comas-Cardona Christophe Aufrere Christophe Binetruy Francisco Chinesta 《International Journal of Material Forming》2017,10(3):317-328
The fundamental macroscopic material property needed to quantify the flow in a fibrous medium viewed as a porous medium is the permeability. Composite processing models require the permeability as input data to predict flow patterns and pressure fields. As permeability reflects both the magnitude and anisotropy of the fluid/fiber resistance, efficient numerical techniques are needed to solve linear and nonlinear homogenization problems online during the flow simulation. In a previous work the expressions of macroscopic permeability were derived in a double-scale porosity medium for both Newtonian and rheo-thinning resins. In the linear case only a microscopic calculation on a representative volume is required, implying as many microscopic calculations as representative microscopic volumes exist in the whole fibrous structure. In the non-linear case, and even when the porous microstructure can be described by a unique representative volume, microscopic calculation must be carried out many times because the microscale resin viscosity depends on the macroscopic velocity, which in turn depends on the permeability that results from a microscopic calculation. Thus, a nonlinear multi-scale problem results. In this paper an original and efficient offline-online procedure is proposed for the efficient solution of nonlinear flow problems in porous media. 相似文献