【正文】 第一篇 人體疾病第一章對(duì)人體的簡(jiǎn)要概述使我們對(duì)兩個(gè)被認(rèn)為是醫(yī)學(xué)基礎(chǔ)的不同學(xué)科有了初步認(rèn)識(shí)，這兩個(gè)學(xué)科就是解剖學(xué)與生理學(xué)。然而不把病理學(xué)包括進(jìn)去，這種概述是不完整的，因?yàn)椴±韺W(xué)是研究疾病引起的結(jié)構(gòu)和功能變化的學(xué)科。實(shí)際上，現(xiàn)代對(duì)疾病的研究方法強(qiáng)調(diào)病理學(xué)與生理學(xué)的密切關(guān)系，并強(qiáng)調(diào)在治療任何人體疾病時(shí)了解病理學(xué)與生理學(xué)基礎(chǔ)的必要性。The brief survey of the human body in Chapter One has given us a glimpse into two different studies that are considered the fundamentals of medical sciences, namely anatomy and physiology. However, the picture is not plete without considering pathology, the science that deals with the structural and functional changes produced by the disease. In fact, the modern approach to the study of disorder emphasizes the close relationship of the pathological and physiological aspects and the need to understand the fundamentals of each in treating any body diseases. 那么什么是疾病呢？它可以被定義為正常機(jī)能或者部分機(jī)能遭受損害時(shí)的一種狀態(tài)。每一種生物，無(wú)論植物還是動(dòng)物，都會(huì)生病。例如，人類(lèi)常常被微小的細(xì)菌感染，但是細(xì)菌又轉(zhuǎn)而可能被更加微小的病毒感染。Then what is a disease? It may be defined as a condition that impairs the proper function of the body or of one of its parts. Every living thing, both plants and animals, can succumb to disease. People, for example, are often infected by tiny bacteria, but bacteria, in turn, can be infected by even more minute viruses. 世界上有數(shù)百種疾病,每一種都有其特定的癥狀和體征，這些都是醫(yī)生診斷疾病的線(xiàn)索。癥狀是病人自己能覺(jué)察到的，比如，高燒、流血或者疼痛。而體征則是醫(yī)生能夠觀(guān)察到的，比如，血管擴(kuò)張或內(nèi)器官腫大。Hundreds of different diseases exist. Each has its own particular set of symptoms and signs, clues that enable a physician to diagnose the problem. A symptom is something a patient can detect, such as fever, bleeding, or pain. A sign is something a doctor can detect, such as a swollen blood vessel or an enlarged internal body organ. 疾病可按不同的標(biāo)準(zhǔn)來(lái)分類(lèi)。例如，流行病是感染某一地區(qū)許多人的疾病。 當(dāng)它年復(fù)一年地發(fā)生在同一地區(qū)，就成了一種地方病。急性病發(fā)作快、病程短。例如，急性心臟病發(fā)作常常沒(méi)有前兆，而且會(huì)很快致命。慢性病發(fā)病緩慢，但病程有時(shí)會(huì)長(zhǎng)達(dá)數(shù)年。風(fēng)濕熱正是由于發(fā)病慢、病程長(zhǎng)而成為一種慢性病。介于急性與慢性之間的另一種類(lèi)型被稱(chēng)為亞急性。Diseases can be classified differently. For instance, an epidemic disease is one that strikes many persons in a munity. When it strikes the same region year after year it is an endemic disease. An acute disease has a quick onset and runs a short course. An acute heart attack, for example, often hits without warning and can be quickly fatal. A chronic disease has a slow onset and runs a sometimes yearslong course. The gradual onset and long course of rheumatic fever makes it a chronic ailment. Between the acute and chronic, another type is called subacute. 疾病也可以依其病原體來(lái)劃分，例如，傳染病指可以在人與人之間傳播的疾病，如可通過(guò)咳嗽或打噴嚏造成的飛沫進(jìn)行傳播。極小的有機(jī)體，如細(xì)菌和真菌,可導(dǎo)致傳染病。病毒和小蟲(chóng)子也可以。不論病原體是什么，只要它存活于受感染的人體內(nèi)就能傳染給別人。有時(shí)，一種致病菌侵入人體后，該人卻沒(méi)有顯示患病的癥狀。于是無(wú)癥狀的病原攜帶者甚至在自己也不知情的情況下就把疾病傳染給了他人。Diseases can also be classified by their causative agents. For instance, an infectious, or municable, disease is the one that can be passed between persons such as by means of airborne droplets from a cough or sneeze. Tiny organisms such as bacteria and fungi can produce infectious diseases. So can viruses and tiny worms. Whatever the causative agent might be, it survives in the person it infects and is passed on to another. Sometimes, a diseaseproducing organism gets into a person who shows no symptoms of the disease. The asymptomatic carrier can then pass the disease on to someone else without even knowing he has it. 非傳染性疾病是由身體機(jī)能失調(diào)引起的,這包括器官或組織退化、異常細(xì)胞生長(zhǎng)以及異常的血液生成和血液循環(huán)。當(dāng)然也包括胃、腸、內(nèi)分泌系統(tǒng)和泌尿生殖系統(tǒng)的紊亂。一些疾病也可能由飲食不足、身體抵抗力下降或神經(jīng)系統(tǒng)運(yùn)行不良造成。Noninfectious diseases are caused by malfunctions of the body. These include organ or tissue degeneration, erratic cell growth, and faulty blood formation and flow. Also included are disturbances of the stomach and intestine, the endocrine system, and the urinary and reproductive systems. Some diseases can be caused by diet deficiencies, lapses in the body’s defense system, or a poorly operating nervous system. 心理因素和社會(huì)因素也會(huì)引發(fā)殘疾和疾病。這些疾病包括毒品成癮、肥胖、營(yíng)養(yǎng)不良和由污染造成的健康問(wèn)題。Disability and illnesses can also be provoked by psychological and social factors. These ailments include drug addiction, obesity, malnutrition, and pollutioncaused health problems. 而且，上千種乃至更多的遺傳性出生缺陷由基因變異引起。由于小小的基因負(fù)責(zé)產(chǎn)生許多身體所需的化學(xué)物質(zhì)，它們的缺失或者運(yùn)行不良都會(huì)嚴(yán)重?fù)p害健康。影響人體化學(xué)反應(yīng)的基因失調(diào)被稱(chēng)為先天性代謝失調(diào),某些智力發(fā)育遲緩有遺傳性。Furthermore, a thousand or more inheritable birth defects result from alternations in gene patterns. Since tiny genes are responsible for producing the many chemicals needed by the body, missing or improperly operating genes can seriously impair health. Genetic disorders that affect body chemistry are called inborn errors of metabolism. Some forms of mental retardation are hereditary. 病菌如何侵襲身體人類(lèi)生活的世界里有許多其他生物為食物和繁衍而競(jìng)爭(zhēng)。很多致病生物，即病原體，通常被廣義地稱(chēng)為病菌，能侵入人體并利用其細(xì)胞和液體來(lái)滿(mǎn)足自己的需求。一般來(lái)講，身體防御系統(tǒng)能夠抵抗這些入侵者。Humans live in a world where many other living things pete for food and places to breed. The pathogenic organisms, or pathogens, often broadly called germs that cause many diseases, are able to invade the human body and use its cells and fluids for their own needs. Ordinarily, the body’s defense system can ward off these invaders. 病原體能通過(guò)多種方式進(jìn)入人體。一些病原體是被吸入人體的，如引起普通感冒、肺炎和結(jié)核病的病菌；有的是通過(guò)性接觸進(jìn)入人體的，如引起性病的病原體；還有的是通過(guò)受污染的食物、水或器皿進(jìn)入人體，比如引起肝炎、霍亂和傷寒的病原體。Pathogenic organisms can enter the body in various ways. Some—such as those that cause the mon cold, pneumonia, and tuberculosis—are breathed in. Others—such as those that cause venereal diseases—enter through sexual contact of human bodies. Still others—such as those that cause hepatitis, colitis, cholera, and typhoid fever—get in the body through contaminated food, water or utensils. 昆蟲(chóng)作為媒介或者病原體攜帶者傳播疾病。蒼蠅能將病菌從人類(lèi)的排泄物或其他腐爛的物質(zhì)帶到食物和飲料中；蚊子、虱子或其他媒介動(dòng)物的叮咬也會(huì)將病菌傳入人體。Insects can spread disease by acting as vectors, or carriers. Flies can carry germs from human waste or other tainted materials to food and beverages. Germs may also enter the body through the bite of a mosquito, louse, or other insect vector. 身體如何抵抗疾病作為第一條防線(xiàn)，健康的身體有許多物理屏障來(lái)抵御感染。覆蓋在體表或者器官開(kāi)口處的皮膚和粘膜能在很大程度上抵抗細(xì)菌或其他感染體的入侵。如果這些物理屏障遭到損壞或燒傷，身體對(duì)感染的抵抗力就會(huì)下降。在一些較輕的病情中，可能只會(huì)發(fā)生癤子和丘疹。在較重的情況下，身體的大面積區(qū)域則可能會(huì)被感染。As a first line of defense, a healthy body has a number of physical barriers against infection. The skin and mucous membranes covering the body or lining its openings offer considerable resistance t