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a frivolous lack of prudence

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/08/05 18:59:39」(JST)

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Light-headedness is a common and often unpleasant sensation of dizziness^[1] and/or feeling that one may be about to faint, which may be transient, recurrent, or occasionally chronic. In some cases, the individual may feel as though his or her head is weightless. The individual may also feel as though the room is "spinning" or moving (vertigo). Most causes of dizziness are not serious and either cure themselves quickly or are easily treated.

Keeping a sense of balance requires the brain to process a variety of information from the eyes, the nervous system, and the inner ears. However, if the brain can't process signals from all of these locations, if the messages are contradictory, or if the sensory systems aren't functioning properly, an individual may experience dizziness and loss of balance.

Causes[edit source | edit]

Light-headedness can be simply (and most commonly) an indication of a temporary shortage of blood or oxygen to the brain due to a drop in blood pressure, rapid dehydration from vomiting, diarrhea, or fever, or from playing a wind instrument. Other causes are low blood sugar, hyperventilation, panic attacks, and anaemia. It can also be a symptom of many other conditions, some of them serious, such as heart problems (including abnormal heart rhythm or heart attack), respiratory problems such as pulmonary embolism, and also stroke, bleeding, and shock. If any of these serious disorders is present, the individual will usually have additional symptoms such as chest pain, a feeling of a racing heart, loss of speech or change in vision.

Many people, especially as they age, experience light-headedness if they arise too quickly from a lying or seated position. Light-headedness often accompanies the flu, hypoglycaemia, common cold, or allergies. Dizziness could be provoked by the use of antihistamine drugs, like Xyzal (Levocetirizine) or by some antibiotics or SSRIs. Nicotine of tobacco products can cause lightheadedness for inexperienced users.

Treatment[edit source | edit]

Treatment for light-headedness depends on the cause or underlying problem. Treatment may include drinking plenty of water or other fluids (unless the light-headedness is the result of water intoxication in which case drinking water is quite dangerous). If a sufferer is unable to keep fluids down from nausea or vomiting, they may need intravenous fluid. Sufferers should try eating something sugary and lying down or sitting and reducing the elevation of the head relative to the body (for example, by positioning the head between the knees).

Other simple remedies include avoiding sudden changes in posture when sitting or lying and avoiding bright lights.

Several essential electrolytes are excreted when the body perspires. When people are out in unusual heat for a long time, sweating can cause a lack of some of these electrolytes, which in turn can cause lightheadedness.

References[edit source | edit]

^ "Chapter 14: Evaluation of the Dizzy Patient". Retrieved 2009-08-06.

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1. 浮動性めまい患者へのアプローチ approach to the patient with dizziness
2. 成人における失神の評価 evaluation of syncope in adults
3. 妊娠早期の臨床症状および診断 clinical manifestations and diagnosis of early pregnancy
4. 起立性低血圧のメカニズム、原因、および評価 mechanisms causes and evaluation of orthostatic hypotension
5. 小児および思春期における浮動性めまいの評価 evaluation of dizziness in children and adolescents

English Journal

The effects of a novel metabotropic glutamate receptor 5 antagonist (AZD2066) on transient lower oesophageal sphincter relaxations and reflux episodes in healthy volunteers.

Rohof WO, Lei A, Hirsch DP, Ny L, Astrand M, Hansen MB, Boeckxstaens GE.SourceAcademic Medical Center, Amsterdam, The Netherlands.
Alimentary pharmacology & therapeutics.Aliment Pharmacol Ther.2012 May;35(10):1231-42. doi: 10.1111/j.1365-2036.2012.05081.x. Epub 2012 Apr 2.
BACKGROUND: Selective metabotropic glutamate receptor 5 (mGluR5) antagonists inhibit transient lower oesophageal sphincter relaxations (TLESRs) in animals and acid reflux in humans.AIM: To assess the effect of single doses of the mGluR5 antagonist AZD2066 on TLESRs and reflux in humans.METHODS: Heal
PMID 22469098

The analysis of 168 randomised controlled trials to test data integrity.

Carlisle JB.SourceConsultant Anaesthetist, Torbay Hospital, South Devon NHS Foundation Trust, Torquay, UK.
Anaesthesia.Anaesthesia.2012 May;67(5):521-37. doi: 10.1111/j.1365-2044.2012.07128.x. Epub 2012 Mar 8.
The purpose of this study was to use some statistical methods to assess if randomised controlled trials (RCTs) published by one particular author (Fujii) contained data of unusual consistency. I searched seven electronic databases, retrieving 168 RCTs published by this author between 1991 and July 2
PMID 22404311