Critical reviews in biomedical engineering
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Hyperthermia, the procedure of raising the temperature of a part of or the whole body above normal for a defined period of time, is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. Clinical hyperthermia falls into three broad categories, namely, (1) localized hyperthermia, (2) regional hyperthermia, and (3) whole-body hyperthermia (WBH). ⋯ The results of combinations of other modalities such as radiotherapy or chemotherapy with hyperthermia as a new treatment strategy are summarized. The article concludes with a discussion of challenges and opportunities for the future.
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Crit Rev Biomed Eng · Jan 2004
ReviewFracture mechanics of cortical bone tissue: a hierarchical perspective.
The performance of bone tissue in the presence of flaws is a highly remarkable one. Bone tissue is the outcome of an adaptive evolutionary process; thus, insight into the mechanisms by which it fails would provide valuable information not only for development of mechanically superior biomimetic materials but also for development of treatment modalities to prevent debilitating bone fractures. Clinically, fractures of skeletal organs occur as a result of aging, disease, overuse, and trauma. ⋯ The challenge of skeletal fragility will be dealt with more efficiently with deeper understanding of the fracture process at each hierarchical size scale. The most recent review on this subject matter was a decade ago, and there have been numerous developments in the fracture mechanics of bone since then. This review recaps the existing literature with an emphasis on the hierarchical nature of the fracture process in bone, entailing the supramolecular, microscopic, and macroscopic scales.
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The aim of this article is to give an overview of recent developments in the field of general anesthesia monitoring. We measure different physiological signals related to the functioning of several nervous systems. ⋯ Modeling of the underlying physiological mechanisms of the anesthesia may help for better understanding the interactions between anesthetic agents and nervous systems. Physiological-model-based general anesthesia monitoring and control can then be considered and optimized for each patient.
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Assessing adequacy of anesthesia requires evaluation of its components: hypnosis, analgesia, and neuromuscular transmission. In order to do this, many methods have been developed that process signals representing different modalities. ⋯ This article presents an overview of the current state of methods available for measuring each of these components. We conclude that, whereas important gains have been made in the area of assessment of hypnosis, mainly owing to the advancement of methods using EEG and auditory evoked potentials, and whereas neuromuscular transmission can be objectively monitored using motor nerve stimulation, assessment of analgesia still contains many challenges.
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Electrical stimulation of the gastrointestinal (GI) tract, analogous to pacing the human heart, is an attractive idea. This is because these organs, like the heart, have their own natural pacemakers, and the electrical signals they generate can be altered by externally delivering certain types of electric currents via intraluminal or serosal electrodes to certain areas of the GI tract. A number of studies on animals have been accomplished successfully to treat a variety of disease models, including gastroparesis, dumping, and short bowel syndrome. ⋯ First the electrophysiology of the GI tract and history of GI electrical stimulation are introduced. Then various methods of electrical stimulation of the stomach and small bowel in healthy animals and models of GI diseases are reviewed. Finally clinical applications of electrical stimulation to GI disorders and their possible mechanisms are discussed.