什么是种族
原本是体质人类学(physical anthropology)惯用的字汇,指称一种人类的分支,他们共同具有族裔相传的体质特质,且是足以明显辨认的独特人类类型,例如高加索人(Caucasoid)、蒙古人(Mongoloid)、黑人(Negroid)等。但现在此一字汇已不太具有科学意义,随着老旧的分类方法(例如头发形式、体格指标)渐被淘汰,取而代之的是DNA比较分析法和基因频率,以及一些相关系数,像是血型检定(blood typing)、氨基酸分泌、先天酵素缺陷(inherited enzyme deficiencies)等。在今天,所有人类的基因都被发现是极为相似,因此大部分研究者都已放弃种族的概念,而改用连群(cline)的概念,意指沿着一条环境或地理转化线而产生的渐变式系列差异。这其实是反映了新的认知,承认人类族群永远处於流动的状态,而基因是恒常地由一个基因库流到另一个基因库,只会受限於生理界限和生态界线。然而族群的相对孤立,确实保存了基因的差异,也使得人群在一段长时期中,可以拥有最强的能力去适应气候和疾病;因此现存的族群完全是基因「混合」(mixed),但他们之间的差异其实并不能将他们进行简单分类。今天「种族」这个字汇基本上是社会学的名词,使拥有相同外在体质特徵及文化历史共同性的群体能自我确认。亦请参阅climatic adaptation, human、ethnic group、racism。
race
Term once commonly used in physical anthropology to denote a division of humankind possessing traits that are transmissible by descent and sufficient to characterize it as a distinct human type (e.g., Caucasoid, Mongoloid, Negroid). Today the term has little scientific standing, as older methods of differentiation, including hair form and body measurement, have given way to the comparative analysis of DNA and gene frequencies relating to such factors as blood typing, the excretion of amino acids, and inherited enzyme deficiencies. Because all human populations today are extremely similar genetically, most researchers have abandoned the concept of race for the concept of the cline, a graded series of differences occurring along a line of environmental or geographical transition. This reflects the recognition that human populations have always been in a state of flux, with genes constantly flowing from one gene pool to another, impeded only by physical or ecological boundaries. While relative isolation does preserve genetic differences and allow populations to maximally adapt to climatic and disease factors over long periods of time, all groups currently existing are thoroughly “mixed” genetically, and such differences as still exist do not lend themselves to simple typologizing. “Race” is today primarily a sociological designation, identifying a class sharing some outward physical characteristics and some commonalities of culture and history. See also climatic adaptation, ethnic group, racism.
-
什么是新生儿
从娩出开始至出生后28天的婴儿。这个时期称为新生儿期。约90%以上的新生儿为正常新生儿,其他为低出生体重儿、早产儿、小于胎龄儿、过期产儿以及巨大儿等。正常新生儿通常指孕37~42周娩出的体重在2500~4000g之间,各器官发育相对成熟的足月儿。新生儿期的特点是婴儿...
-
什么是捏积
以手捏拿患者背部脊中线的推拿方法。又称捏脊。多用于治疗小儿疳积等病证。晋代葛洪《肘后方·治卒腹痛方》载“拈取其脊骨皮,深取痛引之,从龟尾至顶乃止,未愈更为之。”此是捏脊疗法的最早文字记载。此法在历代推拿著作中记述不多,但因其方法简便,效果显著,在民间广...
-
什么是脂溢性角化病
皮肤老化的一种常见表现。又称老年疣、基底细胞乳头瘤。多在40岁以后出现。最初为一境界清楚的淡褐色斑,约0.5~1.0cm大小,俗称老年斑或寿斑。以后渐隆起,表面光滑或成乳头瘤状,有的表面还有一层油脂性的痂,损害的颜色从浅褐色至黑色不等。脂溢性角化可发生在皮肤的任...
-
什么是活体组织检查
对患者少量的病变组织或细胞材料进行的显微镜病理形态学检查。简称活检。是广泛应用的诊断技术之一。取患者的小块病变组织或体液或细胞(常用外科手术切取、钳取或刮取、抽吸等方法获得)。经过病理组织学方法或细胞学方法,制成薄切片,再在光学或电子显微镜下观察,作...