时间:2018-12-30 作者:英语课 分类:英语语境识词


英语课

  Unit 88

Siamese Twins

Siamese twins are formed from a single egg which develops into two almost separate parts of cells. Normally, each part becomes an identical twin. However, cells in Siamese twins become confused about where they are in the body -- indeed which of the two Siamese twins they are actually in.

In normal fetus 1 development every cell knows where it is in the body because the neighboring cells produce chemical messages. So a skin cell knows not only it is skin, but that it is, say, nose skin, rather than chin or ear or lip skin. In Siamese twins these chemical messages don't work properly -- ho can they? The end results can be very odd: a single organism with two heads, tow hearts, four legs and arms -- or is that single organism actually two people, two individual Siamese twins?

Although at first sight each appeared to have a separate well-formed body with some joining at the lower body, detailed 2 tests showed these Siamese twins were very unequal. In some cases, one was providing the heart, lungs and many other basic functions. The other Siamese twin was vey poorly equipped for separate life. To make matters worse, these Siamese twins were to some extent dependent on each other. If separated, the stronger and more capable Siamese twin would need huge amounts of surgery over the following years, and was likely to suffer significant handicap.

It is a brave doctor indeed who is willing to take the knife to two Siamese twins, both of which are at that point alive and growing, and see perhaps both Siamese twins die in the operating room or very shortly afterwards. It is easier to go ahead if the parents want their Siamese twins separated and understand and accept the risks -- but what if you have had to force the whole thing on them in the first place? A key Problem in Siamese twin decisions is that the parents themselves may no always agree on the separation, and it is common for them to feel somehow that the birth of Siamese twins is their fault, or to blame each other, doctors, society or God. The natural joy of birth has been replaced by deep grief for the loss of one or two perfectly 3 normal children.

And there is another issue. The survivor 4 of these Siamese twins would need huge care efforts. This would be unlikely in some cultures and parents may feel very angry at medical interference.

On balance, doctors should tread with great care when it is a human right and the responsibility for parents to make decisions on behalf of their children to refuse certain medical treatment.



n.胎,胎儿
  • In the fetus,blood cells are formed in different sites at different ages.胎儿的血细胞在不同时期生成在不同的部位。
  • No one knows why a fetus is not automatically rejected by the mother's immune system. 没有人知道为什么母亲的免疫系统不会自动排斥胎儿。
adj.详细的,详尽的,极注意细节的,完全的
  • He had made a detailed study of the terrain.他对地形作了缜密的研究。
  • A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。
adv.完美地,无可非议地,彻底地
  • The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
  • Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。
n.生存者,残存者,幸存者
  • The sole survivor of the crash was an infant.这次撞车的惟一幸存者是一个婴儿。
  • There was only one survivor of the plane crash.这次飞机失事中只有一名幸存者。
学英语单词
A arrival factor
Adair, John
Amoeba tetragena
animes
anterior iliac artery
Anthony Powell
athabascaite
Austronesianist
band saw blade tensioner
bioreacter
bloater
botryogenite
bovine serum
bridgeplates
broodstocks
buy secondary hand
careless of
cheetahs
colubrinol
compass in binnacle
conditional information
conforaneous
county agents
crew stairs
Cumulative Return
deaerator adjustment test
decimetric feeder
deoxyribonucleic protein
dermochrome
diabetic neuropathy
dome kiln
education received
elevating gear
enthalpy flux
externally mounted mechanical seal
fade-out
field pick up
field replacement unit
Forlandsundet
get into a temper
goings-on
gyroes
h(a)ematology
hits on me
huytons
insculptor
interior fittings
iodoform albuminate
iron wire brush
iron-bound
jadder
khazei
land storage
layered network
line transect method
logarithmic temperature scale
low temperature dry cell
make an attack upon
markois
matching quadrupole
maximum traverse of boring spindle
Mesolithic Period
meteorological diversity scenery
microcivilizations
microetch
minuteman
mismeter
montpellier codex
multistage stratified random sampling
multitrack error
Neofiber alleni
new management
Nimrah
nonlinear damper
Old World jay
pack duck
peace-keeping force
phakotoxic
plitch
power range channel
precancerous leukokeratosis
put up the cards against someone
rack shaping machine
resoliving power test target
retrotrans-position
senior debt
shielded ball bearing
sliding wheel shaft
superpeople
Three Estates (of the Realm)
TKing
toit
tool sharpener
totalling meter
turning sander
unpopped
unsupported barrel
viuras
wakeboarder
water level fluctuations
WSHF
Zeiss orthometer lens