Nordisk medicin
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As phototoxic and photoallergic reactions have been recognised as unwanted skin manifestations caused by any of several hundred substances, drugs and chemicals, it is essential to determine the potential photo-sensitising properties of such substances before they are introduced in clinical therapy or made available on the market, in order to avoid such reactions. In cases of phototoxic reactions, the patient presents with skin changes resembling sunburn, sometimes accompanied by blistering, whereas in cases of photoallergic reactions the skin changes are similar to those of allergic contact dermatitis. The two most important aids to clinical investigation are determination of the erythema treshold, or the minimal erythema dose, and photopatch testing. The article reviews the basic mechanisms of photosensitisation, outlining the most important differences between phototoxic and photoallergic reactions, summarises the most frequent photosensitisers, and presents the diagnostic procedures, including the tests used in experimental phototoxicity.
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Physicians responding to emergency calls on board airliners in intercontinental traffic may not be aware of certain legal complications which may arise. For instance, the medical practitioner may hold a license valid in one country, the air carrier may be registered in another, and the patient may be a third state national. Legislation varies between nations, as do court decisions. ⋯ Likewise, appraisal and use of medical equipment on board are discussed, as are issues concerning responsibility and liability when equipment is used in supposedly "trained hands". Main themes in the current international medico-legal debate are considered with emphasis on the "Good Samaritan Principle", the responsibility of commercial air carriers, and telemedicine with insurance against law suits. The article concludes with some practical advice to the travelling medical community.
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The main objective of neurointensive care is to counteract the development of secondary brain ischemia. The management is focused on preventing, detecting and correcting secondary insults that are likely to produce ischemic brain damage. This requires intensive multimodality monitoring of the brain. ⋯ PET may be used to guide therapeutic intervention, to evaluate the effect of treatment, to validate new techniques for monitoring of the brain and to determine the efficacy of potential neuroprotective drugs. The possibilities that PET offers in neurointensive care and research are illustrated. The experiences from the application of PET in the evaluation of pharmacological treatment of increased intracranial pressure in head injured patients and the use of PET in combination with intracerebral microdialys, in an MCA-occlusion-reperfusion primate model and in patients with subarachnoid hemorrhage, to validate intracerebral microdialysis as an instrument for chemical monitoring of the brain during neurointensive care, are reported.
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Increased pain fibre activity in response to tissue injury results in changes in gene expression and prolonged changes in nerves and their environment. The resulting hyperalgesia and prolonged spontaneous pain are due both to increased sensitivity of peripheral nociceptors (primary hyperalgesia) and to faciliated spinal cord transmission (secondary hyperalgesia, receptive field expansion and allodynia). Hyperexcitability of dorsal horn neurones is first triggered by increased neuronal barrage into the central nervous system ("wind-up"), and later by retrograde chemical influences from the peripheral inflammation (central sensitisation). ⋯ In the case of persistent pain, there is evidence of pathological reduction of the supraspinal net inhibitory actions in combination with ectopic afferent input in damaged nerves. Hence, the pathology of chronic pain (neuropathic pain) differs from that of nociceptive pain and conventional pharmacological treatment of chronic central pain is usually less successful than treatment of inflammation-related pain. The many newly discovered mechanisms for the transmission and modulation of pain impulses are characterised by complex activity-dependent plasticity, which means that therapeutic strategies for persistent pain must be adapted to changing targets--either at the site of injury or at other sites in the central nervous system.