Joint deterioration

In previous decades, a pyramid model dominated the treatment of rheumatoid arthritis. Early in the course of the disease, sahcylates were used to control pain and stiffness. If sahcylates were poorly tolerated or began to lose efficacy, they were discontinued and a different NSAID was used. As the efficacy of NSAID therapy waned and joint deterioration progressed, treatment with a DMARD was added. DMARDs were employed... 

E. Treatment guidelines suggest the use of DMARDs early in the course of rheumatoid arthritis to slow the joint deterioration associated with the disease. Methotrexate is the DMARD of choice for people with moderate to severe forms of rheumatoid arthritis. Although NSAIDs can decrease methotrexate clearance, NSAIDs can be safely used with the low doses of methotrexate used in the therapy of rheumatoid arthritis. Methotrexate is highly teratogenic and should not be used by women who are or may become pregnant. 

Kashin-Beck Disease (KBD), a condition characterized by collagen breakdown and joint deterioration, was the second human disease to be associated with selenium deficiency (Dongxu 1990). Seasonal incidence variations suggest the involvement of infectious agents and of mycotoxins, as well as deficiencies of certain other trace elements (iodine, boron, germanium) (Dongxu 1990, Peng et al. 2000). 

The effects of environmental conditions on the durability of adhesive joints have been discussed in Section II.A.5.a. Care should be exercised in comparing the results of outdoor exposure tests, since differences may be observed depending upon the particular location of the bonded structure. For example, Minford has reported that joint deterioration is more rapid in an exposed jungle site than in a secluded jungle site, where the joints are protected from direct sunlight. The daily temperature excusions of the joints in the exposed location are assumed to be responsible for this difference. In general, it is found that a cycling environment is more harmful than one in which the conditions are more constant. 

Erosion is the deterioration of a surface by the abrasive action of solid particles in a liquid or gas, gas bubbles in a liquid, liquid droplets in a gas or due to (local) high-flow velocities. This type of attack is often accompanied by corrosion (erosion-corrosion). The most significant effect of a joint action of erosion and corrosion is the constant removal of protective films from a metal s surface. This can also be caused by liquid movement at high velocities, and will be particularly prone to occur if the solution contains solid particles that have an abrasive action. 

Usually, copper surfaces are mated when joints must be periodically discoimected because copper offers low resistance and good wear. Junctions between copper and aluminum bus bars are improved by using a copper—aluminum transition joint that is welded to the aluminum member. Deterioration of aluminum shunt connections by arcing is eliminated when a transition joint is welded to both the primary bar and the shunting bar. 

These are generally the same as the routine tests. No field test as regards the power frequency voltage withstand or HV lest is normally prescribed on a bus system, which has already been tested at the manufacturer s works. Repealed application of high voltage may deteriorate the insulating properties of the insulation system and its life unless modification has been carried out at site or where the insulation of joints between the busbars can be completed only after erection at site. In such cases, if this test becomes essential it can be conducted,... 

A lubricant-starved chain drive shows a brownish or rusty coloration around the joints and in the roller-bushing areas when the link is disassembled and the pin inspected. The normal highly polished surface of the pin will have deteriorated to a roughened, grooved, or galled surface that can eventually destroy the hardened surfaces of the chain parts and increase wear until the drive is completely destroyed. This also will be hue if a lubricant that does not meet the chain s technical specifications is used. 

The biological contamination and the hardness of underground water are the two very serious problems of water. Dissolved salts deteriorate water quality and may cause diseases related to joints and bones, while infected water may cause many water-borne diseases such as cholera, dysentery, typhoid etc. Ultrasound may disinfect the potable water by blasting off micro organisms such as zooplanktons, phytoplanktons, pathogenic bacteria and produce germ-free water in few minutes of... 

A third set of samples was constructed from Al-Tl. As observed using other metallic adherends, little difference in joint strength was observed over a period of 60 days between samples in which the substrates had been alkaline cleaned, lubricated or left untreated. (Figure 7). In addition, the most rapid deterioration in bond strength occurred in environments where high concentrations of chloride ions were present, as depicted by salt fog and cycle test data. 

In vitamin C avitaminosis, or scurvy, the joints become painful and the gums bleed and deteriorate, resulting in tooth loss. Gangrene and infections may also occur, and wounds do not heal properly. These symptoms all result from impaired collagen synthesis and... 

A significant contribution of Raman spectroscopy to the analytical characterization of biomedical issues has been made in the area of biomaterials, especially in the identification of biodegradation and deterioration [1, 2]. The general impact of Raman spectroscopy on the study of biomaterials has been described by this author in three recent review articles [3-5]. In this chapter, the topic of Raman characterization of biomaterials is revisited with particular emphasis placed on those biomaterials widely employed for load-bearing surfaces in artificial joints. Important recent case studies are presented to illustrate the power of the Raman technique to answer key questions of broad medical, scientific, and technological interest. The analytical and physical science lying behind the Raman effect is shown to contribute to the accumulation of a wealth of fundamental information about the medical and technical achievements of prosthesis makers. 

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