WordNet

cause to flow; "The artist flowed the washes on the paper"
the amount of fluid that flows in a given time (同)flow_rate, rate of flow
any uninterrupted stream or discharge
cover or swamp with water
the act of flowing or streaming; continuous progression (同)stream
the motion characteristic of fluids (liquids or gases) (同)flowing
move or progress freely as if in a stream; "The crowd flowed out of the stadium" (同)flux
be abundantly present; "The champagne flowed at the wedding"
the approximate amount of something (usually used prepositionally as in `in the region of' (同)neighborhood
the extended spatial location of something; "the farming regions of France"; "religions in all parts of the world"; "regions of outer space" (同)part
a knowledge domain that you are interested in or are communicating about; "it was a limited realm of discourse"; "here we enter the region of opinion"; "the realm of the occult" (同)realm
a large indefinite location on the surface of the Earth; "penguins inhabit the polar regions"
smear with blood, as in a hunting initiation rite, where the face of a person is smeared with the blood of the kill
temperament or disposition; "a person of hot blood"
people viewed as members of a group; "we need more young blood in this organization"
the fluid (red in vertebrates) that is pumped through the body by the heart and contains plasma, blood cells, and platelets; "blood carries oxygen and nutrients to the tissues and carries away waste products"; "the ancients believed that blood was the sea
of or relating to the cerebrum or brain; "cerebral hemisphere"; "cerebral activity"
involving intelligence rather than emotions or instinct; "a cerebral approach to the problem"; "cerebral drama" (同)intellectual
related or limited to a particular region; "a regional dialect"
characteristic of a region; "regional flora"

PrepTutorEJDIC

《副詞巳句始を伴って》〈気体・液体・電気などが〉『流れる』 / 《副詞[句]を伴って》〈言葉・人々などず〉流れるように続く / 〈心・場所などが〉(…で)いっぱいになる,満ちあふれる《+『with』+『名』》 / 《副詞[句]を伴って》〈髪・服などが〉長く垂れる;風になびく / 〈潮が〉満ちる / (…から)生じる,発生する《+『from』+『名』》 / 〈C〉《単数形で》(気体・液体・電気などの)『流れ』《+『of』+『名』》 / 〈C〉《単数形で》(言葉・人などの)絶え間のない(よどみのない)流れ《+『of』+『名』》 / 〈C〉《単数形で》(…の)洪水,はんらん《+『of』+『名』》 / 〈U〉《the flow》満ち潮,上げ潮
(地理的な)『地域』,『地帯』;(特に広大な)地方 / 《複数形で》(宇宙などの)区分,界,属 / (身体の)部分 / (学問などの)分野,領域 / 《複数形で》(都会から離れた)地方
『血』,『血』液 / 流血(bloodshed);殺人 / 気質,気性,血気,血潮 / 『血統』,血縁(kinship);生まれ,家柄;《the~》王家の血統 / (人種・出身国の)系 / 〈人〉‘に'初めての経験をさせる / 〈猟犬〉‘に'初めて獲物を血を味わわせる
大脳の,脳の / 頭脳的な,知的な
地方の,地域の;地方に特有の,局地的な

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2012/11/09 08:21:23」(JST)

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[Wiki en表示]

Cerebral blood flow, or CBF, is the blood supply to the brain in a given time.^[1] In an adult, CBF is typically 750 millilitres per minute or 15% of the cardiac output. This equates to 50 to 54 millilitres of blood per 100 grams of brain tissue per minute.^[2]^[3]^[4] CBF is tightly regulated to meet the brain's metabolic demands.^[2]^[5] Too much blood (a condition known as hyperemia) can raise intracranial pressure (ICP), which can compress and damage delicate brain tissue. Too little blood flow (ischemia) results if blood flow to the brain is below 18 to 20 ml per 100 g per minute, and tissue death occurs if flow dips below 8 to 10 ml per 100 g per minute. In brain tissue, a biochemical cascade known as the ischemic cascade is triggered when the tissue becomes ischemic, potentially resulting in damage to and death of brain cells. Medical professionals must take steps to maintain proper CBF in patients who have conditions like shock, stroke, and traumatic brain injury.

Cerebral blood flow is determined by a number of factors, such as viscosity of blood, how dilated blood vessels are, and the net pressure of the flow of blood into the brain, known as cerebral perfusion pressure, which is determined by the body's blood pressure. Cerebral blood vessels are able to change the flow of blood through them by altering their diameters in a process called autoregulation; they constrict when systemic blood pressure is raised and dilate when it is lowered^[6] Arterioles also constrict and dilate in response to different chemical concentrations. For example, they dilate in response to higher levels of carbon dioxide in the blood.^[6]

CBF is equal to the cerebral perfusion pressure (CPP) divided by the cerebrovascular resistance (CVR):^[7]

CBF = CPP / CVR

Control of CBF is considered in terms of the factors affecting CPP and the factors affecting CVR. CVR is controlled by four major mechanisms:

Metabolic control (or 'metabolic autoregulation')
Pressure autoregulation
Chemical control (by arterial pCO₂ and pO₂)
Neural control

Functional magnetic resonance imaging and positron emission tomography are neuroimaging techniques that can both be used to measure CBF. These techniques are also used to measure regional CBF (rCBF) within a specific brain region.

Role of intracranial pressure

Increased intracranial pressure (ICP) causes decreased blood perfusion of brain cells by mainly two mechanisms:

Increased ICP constitutes an increased interstitial hydrostatic pressure that, in turn, causes a decreased driving force for capillary filtration from intracerebral blood vessels.
Increased ICP compresses cerebral arteries, causing increased cerebrovascular resistance (CVR).

References

^ Tolias C and Sgouros S. 2006. "Initial Evaluation and Management of CNS Injury." Emedicine.com. Accessed January 4, 2007.
^ ^a ^b Orlando Regional Healthcare, Education and Development. 2004. "Overview of Adult Traumatic Brain Injuries." Accessed 2008-01-16.
^ Shepherd S. 2004. "Head Trauma." Emedicine.com. Shepherd S. 2004. "Head Trauma." Emedicine.com. Accessed January 4, 2007.
^ Walters, FJM. 1998. "Intracranial Pressure and Cerebral Blood Flow." Physiology. Issue 8, Article 4. Accessed January 4, 2007.
^ Singh J and Stock A. 2006. "Head Trauma." Emedicine.com. Accessed January 4, 2007.
^ ^a ^b Kandel E.R., Schwartz, J.H., Jessell, T.M. 2000. Principles of Neural Science, 4th ed., McGraw-Hill, New York. p.1305
^ AnaesthesiaUK. 2007. Cerebral Blood Flow (CBF). Accessed 2007-10-16.

UpToDate Contents

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Intracranial pulsatility is associated with regional brain volume in elderly individuals.

Wåhlin A, Ambarki K, Birgander R, Malm J, Eklund A.SourceDepartment of Radiation Sciences, Umeå University, Umeå, Sweden. Electronic address: Anders.Wahlin@radfys.umu.se.
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Matrix metalloproteinase-2 deletions protect against hemorrhagic transformation after 1h of cerebral ischemia and 23h of reperfusion.

Lu A, Suofu Y, Guan F, Broderick JP, Wagner KR, Clark JF.SourceDepartment of Neurology, University of Cincinnati, Cincinnati, OH 45267-0532, USA. Electronic address: lua@ucmail.uc.edu.
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Central artery stiffness, neuropsychological function, and cerebral perfusion in sedentary and endurance-trained middle-aged adults.

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BACKGROUND: Midlife vascular disease risk is a strong risk factor for late-life dementia. Central arterial stiffness, a hallmark of vascular aging, is associated with accelerated brain aging and cognitive decline. Habitual aerobic exercise is an effective lifestyle strategy to reduce central arteria
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Japanese Journal

Mapping of Cerebral Metabolic Rate of Oxygen using DSC and BOLD MR Imaging : A Preliminary Study

SHIINO Akihiko,YAMAUCHI Hiroshi,MORIKAWA Shigehiro,INUBUSHI Toshiro
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