医学专业英语 阅读一分册 第一章

The muscular system allows the body to move,

and its contractions produce heat, which helps maintain a constant body temperature. Striated

muscles can be consciously controlled. The ends of these muscles are attached to different bones

by connective tissue bands so that when the muscle contracts, one bone moves in relation to the

other. This makes it possible to move the whole body, as when walking, or to move just one part

of

the

body,

as when

bending

a

finger. Contractions

of

the

heart

and

smooth

muscles

are

not

under conscious control. Smooth muscles are found in the walls of organs such as the stomach

and the intestines and serve to move the contents of these organs through the body .

肌肉系统使

躯体运动，肌肉收缩产生的热有助于维持一个恒定 的体温。人体能够有意识地控制条纹肌。

结缔组织使肌肉末端附着于不同的骨面上，所以 当肌肉收缩时，两骨彼此靠近而产生运动。

这也就使整个人体可以运动起来，如走路，运 动躯体某个部位，如弯曲手指。心脏收缩和平

滑肌收缩就不是被意识所控制的。

器官壁内层的平滑肌，

如胃肠壁的平滑肌把胃肠中的物质

运送到全身。

The circulatory system. All parts of the body must have nourishment and oxygen in

order to function and grow, and their waste products must be removed before they accumulate

and poison the body. The circulatory system distributes needed materials and removes unneeded

ones.

It

is

made

up

of

the

heart,

blood

vessels,

and

blood,

which

together

make

up

the

cardiovascular system. The blood is also part of the body's defense system. It has antibodies and

white blood cells that protect the body against foreign invaders.

循环系统：机体的所有部分需

要营养物质 和氧气来使之发挥功能和生长，

也需要在这些器官所产生的废物积聚而危害生命

之前将其排除。

循环系统运送有用物质，

排泄废 物。心血管系统是循环系统的组成之一；心

血管系统包括心脏、

血管及血液。

血液也是机体防御系统的一个部分，

血液中有抗体 及白细

胞来防止机体受到外来的侵袭。

The heart is a muscle that is divided into two nearly identical halves: one half receives blood from

the

lungs

and

sends

it

to

the

rest

of

the

body,

the

other

half

sends

blood

that

has

traveled

through the body back to the lungs. When the heart muscle contracts, the blood is forced out

into arteries and enters small capillaries. Blood returns to the heart through veins.

心脏是一块被分为几乎对等 两半的肌肉。一半吸收来自肺部的血液，并将血液运送到机体

的其余部位，

另一半使流经全身的血液回流人肺。

心脏收缩时，

动 脉把全身血液输送到毛细

血管。静脉输送血液返回心脏。

Also functioning in circulation is the lymphatic system. Some of the fluid that surrounds cells does

not

reenter

the

blood

vessels

directly.

This

fluid,

called

lymph,

returns

to

the

heart

by

way

of

another system of channels - the lymph vessels. Lymph nodes along these vessels filter the fluid

before it reenters the blood. The spleen is a large lymphatic organ that filters the blood.

淋巴系统也是循环系统的一个组成部分。一些 细胞周围的体液不是直接回流入血管通道，

这种体液叫淋巴液，

它是流经另一个管道系统——淋巴管而回流人心脏。

沿淋巴管的淋巴结

< br>将淋巴液过滤，过滤后再回流人血液。脾是一个过滤血液的大淋巴器官。

The respiratory system takes in oxygen from the air and expels carbon dioxide and water vapor.

Air enters the nose and mouth and travels through the larynx, and trachea. The trachea divides to

enter each of the two lungs and then divides more than 20 times to form a very large number of

small air spaces. Oxygen from the air enters the blood through capillaries in the walls of these air

spaces, and the blood release carbon dioxide into the air spaces to be exhaled.

呼吸系统从空气中摄取氧气，并将二氧化碳、水蒸气排 出体外。空气经鼻腔、口腔人喉管、

气管。气管分成左右支气管，各连结左右肺，左右支 气管再分枝

20

多次，在终端形成大量

微小的肺泡。

从空气摄取的氧气流经这些肺泡壁内的毛细血管流入血液，

血液再经肺泡把释

放出的二氧化碳排出体外。

The digestive system consists of a tube extending from the mouth to the anus. In it, food and

fluids

are

taken

in,

moved

through

the

body,

and

broken

down

into

small

molecules

that

are

absorbed into the circulatory system. This breakdown, known as digestion, is both a mechanical

and a chemical process.

Food enters through the mouth, where chewing and saliva start to break it up and make it easier

to swallow. Next, the food travels down through the esophagus to the stomach. Contractions of

the

stomach's

muscular

wall

continue

to

break

down

the

food

mechanically,

and

chemical

digestion continues when acid and enzymes are secreted into the stomach cavity.

消化系统是一个从口腔直到肛门的管道。食物和液体在消化道里被吸收，在肠道里移动时，

被分解成小分子物质后再进入循环系统。

这种分解，即消化，

是一个机械过程，也是一个化

学过程。

食物进入口腔里，咀嚼和唾液开始将食物粉碎，使之便于吞咽。接着，食物经食管人胃。胃

肌壁的收缩继续机械化地分解食物，而当酸和酶分泌入胃腔时，化学性消化开始。

The liquified food gradually passes into the small intestine. In the first part of the small intestine,

called

the

duodenum,

enzymes

from

the

pancreas

are

added.

These

enzymes

complete

the

chemical breakdown of the food. The digestion of fat is aided by bile, which is made in the liver

and stored in the gall bladder. The small intestine of an adult is about 21 feet (6.4 meters) long.

Most of its length is devoted to absorbing the nutrients released during these digestive activities.

液体化食物 逐渐进入小肠。小肠的起始部分叫十二指肠，胰腺分泌的酶辅助食物消化。这

些酶完成食 物的化学分解。

肝脏分泌的胆汁贮存在胆囊内，

胆汁有助于脂肪 消化。

一个成年

人的小肠有

21

英尺（

6.4

米）长。小肠的大部分肠段用来 吸收消化过程中释放的营养物质。

The liquid remainder of the food enters the large intestine, or colon, which is about 12 feet (3.7

meters) long. It is more than twice as wide as the small intestine. In the large intestine most of

the fluid is absorbed, and the relatively dry residues are expelled.

液状的剩余 食物进入大肠，或结肠，它大约有

12

英尺（

< br>3.7

米）长。大肠是小肠的两倍多

宽。大部分液体在大 肠内被吸收，相对干化的残余物被排出体外。

The

urinary

system

maintains

normal

levels

of

water

and

of

certain

small

molecules

such

as

sodium

and

potassium

in

the

body.

It

does

this

by

passing

blood

through

the

kidneys,

two

efficient

filtering

organs

that

get

rid

of

any

excess

of

various

molecules

and

conserve

those

molecules that are in short supply.

泌尿系统维持水分及体内某些小分子物质，如钠、

钾的正常水平。

身体是通过让’

肾过滤血

液来做到这一点的 。

肾是两个有效的过滤器官，

它滤出各种多余的小分子物质，< /p>

保留那些供

应不足的小分子物质。

The fluid that leaves the kidneys, known as urine, travels through a tube called the ureter to the

bladder. The bladder holds the urine until it is voided from the body through another tube, the

urethra.

从肾流出的液体 ，即尿，通过输尿管人膀胱。膀胱起贮存尿液的作用，直到尿经膀胱另一

端的管道排出。

The endocrine system. The two systems that control body activities are the endocrine system and

the

nervous

system.

The

former

exerts

its

control

by

means

of

chemical

messengers

called

hormones.

Hormones

are

produced

by

a

variety

of

endocrine

glands,

which

release

the

hormones directly into the blood stream.

内分泌系统。

内分 泌和神经是调控机体活动的两个系统，

前者依靠其化学信使——激素发挥

作用。激素是由各种内分泌腺体制造，并直接被释放入血流

A

major

gland

is

the

pituitary,

which

is

located

under

the

brain

in

the

middle

of

the

head.

It

produces at least eight hormones, which affect growth, kidney function, and development of the