Medicine, ultrasound

The use of ultrasonic (US) radiation (typical range 20 to 850 kHz) to accelerate Diels-Alder reactions is undergoing continuous expansion. There is a parallelism between the ultrasonic and high pressure-assisted reactions. Ultrasonic radiations induce cavitation, that is, the formation and the collapse of microbubbles inside the liquid phase which is accompanied by the local generation of high temperature and high pressure [29]. Snyder and coworkers [30] published the first ultrasound-assisted Diels-Alder reactions that involved the cycloadditions of o-quinone 37 with appropriate dienes 38 to synthesize abietanoid diterpenes A-C (Scheme 4.7) isolated from the traditional Chinese medicine, Dan Shen, prepared from the roots of Salvia miltiorrhiza Bunge. 

Internal According to operational requirements X-ray systems Angiography (AX) Special systems (SP) Computed tomography (CT) AXIOM Artis of TA Magnetic resonance tomography (MR) Nuclear medicine (NM) Ultrasound (US) Oncology care systems (OCS) Health services (HS) Audiology (A)... 

Ultrasound in Biology and Medicine Biological cell disruption... 

One of the first applications of ultrasound in medicine was the so-called ultrasonic massage introduced in Germany before the Second World War. This was introduced as a substitute for the hands of the masseur in patients who had suffered from fractures and similar injuries. Rubbing movements are capable of improving the circulation very considerably and help also to break down adhesions between muscles and their sheaths that limit the range of movement. The use of ultrasound for the treatment of sporting injuries, particularly strains and tennis elbow is now commonplace as equipment for this purpose is readily commercially available to the physiotherapist. This is one of the first uses of ultrasound in the treatment of medical problems and is part of a new field of medicine called therapeutic ultrasound [15]. 

Low-energy ultrasound was employed to increase by up to 70% the production of shikonin (Fig. 4) in cell cultures of the medicinal herb Lithospermum erythrorhizon. Shikonin exhibits a variety of effects, which includes anti-inflammatory, antigonadotropic and human immunodeficiency virus type 1 (HIV-1) suppression activities. 

American Academy of Dermatology American Association of Physicists in Medicine American College of Medical Physics American College of Nuclear Physicians American College of Radiology American Dental Association American Industrial Hygiene Association American Institute of Ultrasound in Medicine American Insurance Association... 

Wilson, M. and F, Ruzicka (Editor) Modem Imaging of die Liver Applications of Computerized Tomography Ultrasound, Nuclear Medicine and Magnetic Resonance Imaging, Marcel Dekker, Inc., New York, NY, 1989. 

Protection in Nuclear Medicine and Ultrasound Diagnostic Procedures in Children (1983)... 

Kost J, Mitragotri S, Gabbay RA, Pishko M, Langer RS. Transdermal monitoring of glucose and other analytes using ultrasound. Nature Medicine 2000, 6, 347-350. 

Lee S, Nayak V, Dodds J, Pishko M, Smith NB. Glucose measurements with sensors and ultrasound. Ultrasound in Medicine and Biology 2005, 7, 971-977. 

Clark JM, Brancati FL, Diehl AM (2002) Nonalcoholic fatty liver disease. Gastroenterology 122 1649-1657 Coatney RW (2001) Ultrasound imaging principles and applications in rodent research. liar Journal 42 233-247 Cockman MD, Hayes DA, Kuzmak BR (1993) Motion suppression improves quantification of rat liver volume in vivo by magnetic resonance imaging. Magnetic Resonance in Medicine 30 355-360... 

The power of ultrasonic generators is often in the region of 105 Wcm-3. This is sufficient to induce cavitation and generate water or other radicals, and hence the widespread use of ultrasound in medicine should be a matter of possible concern. 

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