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brown fat 棕色脂肪〔冬眠動物體內的生熱脂肪〕。

If one takes such a picture of an unswaddled infant sleeping at room temperature , “ hot spots “ can be seen in the skin overlying brown fat deposits in the neck and interscapular area 如果有人拍下未包裹的嬰兒在室溫下睡覺的照片,將可在頸部和肩胛間的皮膚有“熱斑” 。

brown george

Brown fat is most prominent in newborn animals . in human infants it comprises up to 5 % of body weight , then diminishes with age to virtually disappear by adulthood 棕色脂肪在新生動物中是最重要的。在人類嬰兒身上它占了5的體重,接著隨著年齡增長逐漸減少,到了成人期差不多都消失不見了。

If one takes such a picture of an unswaddled infant sleeping at room temperature , “ hot spots “ can be seen in the skin overlying brown fat deposits in the neck and interscapular area 如果有人拍下未包裹的嬰兒在室溫下睡覺的照片,將可在頸部和肩胛間的皮膚有“熱斑” 。

In contrast to white fat , brown fat is richly vascularized and has numerous unmyelinated nerves which provide sympathetic stimulation to the adipocytes 和白色脂肪組織比較起來,棕色組織有充分的血管浸潤,而且有許多無髓鞘的神經提供交感神經對脂肪細胞的刺激。

Examination of sections of white and brown fat at low magnification reveal dramatic differences in structure , as seen below in images of mouse tissues 棕色脂肪對新生兒,寒冷環境中的小型哺乳類,冬眠動物來說特別重要。

Dissection of a mouse will reveal two large , lobulated masses of brown fat on the dorsal aspect of the thorax , between the scapulae 解剖老鼠后會發現在肩胛骨之間有兩個由小葉片組成的大團塊棕色脂肪。

Brown fat thermogenesis also seems to be of considerable importance to animals coming out of hibernation , allowing them to rewarm 棕色脂肪的產熱對動物從冬眠中醒來,使他們重回溫暖中似乎相當重要。

A good place to observe brown fat is in mice , where it persists into adulthood 老鼠是觀察棕色脂肪最好的樣本,因為在成熟的老鼠中棕色脂肪組織仍會存在。

Masses of brown fat are also to be found around the aorta and in the hilus of the kidney 棕色脂肪團亦可在主動脈四周和腎臟的臍部附近找到。

The heat produced in brown fat can actually be imaged using a thermal ( infrared ) camera 棕色脂肪的產熱可由紅外線攝影機呈像觀察。