1.1 Alzheimer Disease

Alzheimer disease was first described by German psychiatrist and neuropathologist Alois Alzheimer in 1906 as a central nervous system degenerative disease with insidious onset and chronic progressive course, which is the most common form of dementia. Its manifestations mostly are neuropsychiatric symptoms such as progressive dysmnesia, cognitive disorder, personality change and aphasis, which seriously affect the ability of social interactions, career and life (Ming Zhidi, 2012).

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1.2 Senile Dementia

Senile dementia, rather than a particular disease or a nerve pathological process, is defined as a clinical syndrome caused by a variety of reasons with cognitive impairment as its main clinical manifestation. AD is only one kind of senile dementia. The causes of this syndrome can be vascular diseases or metabolic disorders, and even substances intoxication can bring about senile dementia (Ming Zhidi, 2012).  

2 Comparison between Senile Dementia and Alzheimer Disease

From the definitions of these two terms, it can be seen that they are two different concepts, we should not simply regard senile dementia as AD. The two terms belong to different hierarchies. Senile dementia has a wider semantic denotation; it embodies and surpasses the semantic field of AD, just as Manuel Pratique de Terminologie, written by Robert Dubuc and translated by Zhang Yide (1990: 51) pointed out that equivalents of terms of different languages do not always exist, and that a more likely scenario would be that Term A in a language only embodies a part of the semantic field of Term B in another language or Term B partially contains Term A. 来~自^751论+文.网www.751com.cn/

3 Terminology and its Features

3.1 Definition of Terminology

What is a technical term? Feng Zhiwei (2011: 29) gave the concept of “term” a clear definition: “terms are conventional symbols which express or define technical conceptions through speech sounds or written languages; a term can be a word or a phrase; terms that only contain one word are called single-term and terms that contain more than one words are called phrase-term or multi-term.”

The difference between a term and a common word lies in that the semantic denotation of a term is determined by the signified relationship, in other words, it does not have a direct subordinate relationship with the signifier; it requires monosemy and single referentiality (Wu Guoliang, 2009: 2). Also, Feng Zhiwei (2011: 30) mentioned that in terminology the concept or the concepts of a language, i.e. the signified, is or are tried to be determined after identifying this language’s linguistic form, i.e. the signifier, and based on which the judgment of whether the term's linguistic form meets its concept is made. So when considering the name of a concept, people start from what its concept is, that is to say, in terminology, concept comes first and then the name. Since priority is given to the concept of a term, it makes standardization and normalization possible. As a result, the rules of terminology are prescriptive other than descriptive.

3.2 Eponyms

This paper uses AD as a case to study terminological translation, so we also should have some basic knowledge about eponyms which mean terms that are named after personal names. An eponym usually consists of two parts: the first part is the name which may be the surname of the doctor who discovered this disease or the person who made great contribution; the name of a mythological or a historical figure; the name of a protagonist of a novel or the name of a patient; the second part is composed of a single medical term which approximately has two categories: generic terms, such as syndrome, disease, operation and reaction etc. and technical term, such as fascia, anemia, amputation and so on (Wu Wei, 2006: 24).