Noninvasive Methods

The biological and medical sciences are ripe for iastmmentation advances. Whereas most immunoassays (qv) use radioactive materials, the implementation of chemiluminescent methods, enzyme techniques, and electrochemical methods is expected to become more important. New and better noninvasive methods of iavestigation are expected to become more routine. In addition, real-time measurements, whereby analyses of a number of... 

Electrocardiogram A noninvasive method of recording the electrical activity of the heart. 

The size of carotenoid aggregates have been determined by dynamic light scattering (DLS), a noninvasive method (Santos and Castanho 1996). DLS also allows distinguishing between spherical or cylindrical aggregates. The hydrodynamic radii rH of hydrophilic carotenoids in water are given in Table 3.1. Size and molecular structure of the bolaamphiphiles crocin, 3.7, and Cardax,... 

Thus, the formation of isoprostanes is rightly considered as a unique noninvasive method for the estimation of in vivo lipid peroxidation. However, the use of 8-Ao-PGF2a isoprostane (now known as iPF2a-III) as an index of nonenzymatic in vivo peroxidation has some limitations due to the possibility of its formation by COX-1- and COX-2-catalyzed... 

Respiratory alkalosis is associated with low partial pressure of02 (25 to 35 mm Hg) and alkaline pH, but normal bicarbonate. The first two values are measured by arterial blood gas, which also yields partial pressure of carbon dioxide and arterial oxygen saturation. Circulating arterial oxygen saturation can also be measured by an oximeter, which is a noninvasive method that is fairly accurate and useful at the patient s bedside. 

A.G. Cavinato, D.M. Mayes, Z.H. Ge and J.B. CaUis, Noninvasive method for monitoring in fermentation processes using fiberoptic near-infrared spectroscopy. Anal Chem., 62(18), 1977-1982 (1990). 

A new method has been developed for stimulation of the brain trans-cranial magnetic stimulation [TMS]. Magnetic stimulation of the brain may offer a means to examine the importance of the convulsion for ECT effects. TMS is a novel noninvasive method for the stimulation of neurons (for review, see Barker 1991]. High electrical current flow in a spiral of wire induces a magnetic field. The magnetic field produces an electric field that initiates ion flow and consequent membrane depolarization directly in brain tissues. Therefore, magnetic stimulation of deep structures may be achieved with relatively little induced current in the skin or skull and without convulsions [Barker 1991]. 

Mitragotri, S., and J. Kost 2000. Low-frequency sonophoresis A noninvasive method of drug delivery and diagnostics. Biotechnol Prog 16 488. 

Iontophoresis is a local noninvasive method of administration associated with minimal discomfort for the patient. However, this procedure can produce complications, including... 

The most commonly utilized embedded sensor for temperature distribution mapping is the thermocouple. Wilkinson et al.130 developed a simple, in-situ, and noninvasive method of measuring the temperature distribution of a fuel cell with micro-thermocouples. In this study, thermocouples were located in the landing area of the flow field plates (in contact with the GDL of the MEA) of a fuel cell. The temperature data taken at different locations along the flow channel was then used to find each temperature slope, which in turn were related through mathematical equations to the local current density of each location. Thus, the current density distribution in the fuel cell was determined by simple temperature measurements. The results of this approach are discussed in more detail in Section... 

Several noninvasive methods have been proposed to study the tissue conditions around implants, including high-resolution magnetic resonance imaging (MRI) approaches.4,23,24 However, at present, MRI does not have adequate resolution for detailed imaging of the microvasculature, collagen, and protein deposits adjacent to a... 

An alternative to direct intravitreal injection is to use a noninvasive method of ASO delivery employing iontophoresis. The advantage of using low current density iontophoresis is that the ASO intraocular distribution will allow for therapeutic concentrations to be achieved across a large number of tissues, including the anterior uvea and the cornea as well as neural retinal areas. Voigt et al. [9] evalu-... 

The characteristics of the dry skin of AD patients have been widely studied. However, those of HD patients have not been studied in detail, although they also show dry skin with itchiness as in AD patients. In this study, we investigated the functions of SC to characterize the dry skin of AD and HD patients by noninvasive methods. 

Dikstein, S. and Zlotogorski, A., Skin surface hydrogen ion concentration (pH), in Cutaneous Investigation in Health and Disease Noninvasive Methods and Instrumentation (Leveque J.-L., Ed.). New York and Basel Marcel Dekker, Inc., 1988, p. 59. 

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