Biomedical components

The deposition of pyrolytic graphite in a fluidized bed is used in the production of biomedical components such as heart valves, ] and in the coating of uranium- and thorium-carbides nuclear-fuel particles for high temperature gas-cooled reactors, for the purpose of containing the products of nuclear fission.fl" The carbon is obtained from the decomposition of propane (CgHg) or propylene (CgHg) at 1350°C, or of methane (CH4) at 1800°C. Its structure is usually isotropic (see Ch. 4). 

Fluidised-bed CVD is a special technique to coat nuclear-fuel particles for high-temperature gas-cooled nuclear reactors which was developed in the late 1950s. This technique has also been used in other applications, such as the production of biomedical components (e.g. heart valves deposited by pyrolysis carbon) and some special functional coatings on ceramic particles. 

The meyor applications of pyrolytic carbon deposited by fluidized bed are found in the production of biomedical components such as heart valves and in the coating of uranium carbide and thorium carbide nuclear-fuel... 

In Vivo and In Vitro Near-Infrared Spectroscopic Determination of Blood Glucose and Other Biomedical Components with Chemometrics... 

In Vivo and In Vitro NIR Spectroscopic Determination of Biomedical Component with... 

NIR spectral measurements of human skin stretch back to 1950s. Real trials for in vivo and in vitro NIR spectroscopic determination of biomedical components with chemometrics started in 1980s. There have been two major streams for NIR-chemometrics investigations on biomedical components. One is concerned with the quantitative analysis of various biomedical analytes in in vitro samples, especially in human serum, and the other is in vivo blood glucose measurement for possible application to clinical diagnosis. 

NIR spectroscopy has the following advantages for in vivo and in vitro determination of blood glucose and other biomedical components with chemometrics. First, it is a nondestructive and noninvasive analytical technique. Second, no or little pretreatment are requested for the NIR analysis. Third, reagents and preprocessing samples are needless. Forth, NIR allows to carry out multicomponent analysis. Moreover, it requires minimal technical expertise. 

IN VIVO AND IN VITRO NIR SPECTROSCOPIC DETERMINATION OF BIOMEDICAL COMPONENT WITH MWPLSR, CSMWPLS, AND SCMWPLS... 

Chapters 2 and 3 have been replaced (Basic Principles and Theories of Diffuse Reflection), several chapters (4,19,25,26,29, and 37) have been updated (Commercial Instrumentation, Analyses of Textiles and of Baked Products, Advances in the Petrochemical Industry, Polymers, Pharmaceutical Applications, and Process Analysis), and some new chapters (12,18,21,28,29,31,32,33,35, and 38) have been added (Process Sensors, Agro-Forestry Systems, Gas Analysis, Use of NIR at the Bowling Alley, PAT in the Pharmaceutical Industry, Nutraceuticals, Detection of Counterfeit Drugs (e.g., Viagra), NIR Photography in Medicine, Biomedical Components in Blood and Semm, and The Detection of Counterfeit Currency and Turquoise). 

Figure 6 shows the clinical uses of metals in the human body. In many instances metallic implants have to be fixed in to the body and the implants must be compatible with the fixative which may be metallic (screws), ceramic (screws and other components) and/or polymer phases (e.g., glue). In the design of replacement components with high strength it is important that the compatibility of all of the biomedical components is required and investigated before novel implants are placed in the human body. 

Traditional appHcations for latices are adhesives, binders for fibers and particulate matter, protective and decorative coatings (qv), dipped goods, foam, paper coatings, backings for carpet and upholstery, modifiers for bitumens and concrete, and thread and textile modifiers. More recent appHcations include biomedical appHcations as protein immobilizers, visual detectors in immunoassays (qv), as release agents, in electronic appHcations as photoresists for circuit boards, in batteries (qv), conductive paint, copy machines, and as key components in molecular electronic devices. 

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

Biomedical Uses. The molybdate ion is added to total parenteral nutrition protocols and appears to alleviate toxicity of some of the amino acid components in these preparations (see Mineral NUTRIENTS) (97). Molybdenum supplements have been shown to reduce iiitrosarnine-induced mammary carcinomas in rats (50). A number of studies have shown that certain heteropolymolybdates (98) and organometaUic molybdenum compounds (99) have antiviral, including anti-AIDS, and antitumor activity (see Antiviral agents Chemotherapeutics, anticancer). 

Biomedical Applications Due to their excellent blood compatibility (low interaction with plasma proteins) and high oxygen and moisture permeabilities, siloxane containing copolymers and networks have been extensively evaluated and used in the construction of blood contacting devices and contact lenses 376). Depending on the actual use, the desired mechanical properties of these materials are usually achieved by careful design and selection of the organic component in the copolymers. 

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