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the earliest answers come from australia, where a group of medical experts at the queen victoria medical center in melbourne have taken a look at the continent's first nine successful ' in vitro pregnancies. the australians report that the pregnancies themselves seemed to proceed according to plan, but at birth some unusual trends did show up. seven of the nine babies turned out to be girls. six of the nine were delivered by caesarean section ( 剖腹产手术 ) . andone baby, a twin, was born with a serious heart defect and a few days later developed life-threatening problems. what does it all mean? even the doctors don't know for sure, because the numbers are sosmall. the proportion of girls to boys is high, but until there are many more test-tube babies noone will know whether that's something that just happened to be like that or something specialthat happens when egg meets sperm in a test tube instead of a fallopian tube. the same thing istrue of the single heart defect; it usually shows up in only 15 out of 60,000 births in that part of australia, but the fact that it occurred in one out of nine test-tube babies does not necessarilymean that they are at special risk. one thing the doctors can explain is the high number of caesareans. most of the mothers were older, had long histories of fertility problems and in some cases had had surgery on the fallopian tubes, all of which made them likely candidates forcaesareans anyway. the australian researchers report that they are quite encouraged. all the babies are nowmaking normal progress even the twin with the birth defects. 41. what would people be most concerned about according to the author? a. whether the test-tube babies would be legally accepted by society. b. whether the test-tube babies would be normal from pregnancy to birth. c. whether modern medicine is advanced enough for test-tube babies' delivery. d. whether there would be always more girls than boys out of the test-tube babies. 42. what does the latin word "in vitro"(paragraph two) most probably mean? a. normal b. test-tube c. virtual d. fallopian tube 43. the australian experiment of the test-tube babies has the following unusual trends except that a. most of the babies are girls b. most of the babies are delivered by means of surgical operations c. there is a serious heart disease case d. the babies do not appear to be normal 44. which of the following explanations regarding the high number of caesarean operations is not true? a. some mothers have passed the best age for a natural delivery. b. some mothers have physical problems with pregnancy. c. some mothers volunteer to be the candidates of the caesarean operations. d. some mothers have had surgical operations on the fallopian tubes. 45. what is the author's attitude toward the idea of test-tube babies? a. optimistic b. pessimistic --c~ delighted d. irritated passage 4 videodisc holds great promise of helping to meet the needs of american schoolchildren whohave problems seeing, hearing, speaking, or socializing. almost eleven percent of the studentsaged 3-21 in this country have an impairment that affects their ability to benefit from a regulareducation program. handicapped students require special education because they are oftenmarkedly different from most children in one or more of the following ways: mentally retarded,learning-disabled, emotionally disturbed, deaf, visually handicapped, physically handicapped,or other health impairments. the education of these handicapped children is rewarding but challenging. a special education student usually needs a longer period of time to acquire information, repetitive teaching techniques are often beneficial, and an indefatigable consistency on the part of the teacher is frequently necessary. interactive videodisc courseware has characteristics that can be capitalized upon to meet the challenges that special education poses. a videodisc program is infinitely patient, repetition of any videodisc lesson can continue endlessly, and designers can assure absolute consistency within a program.   |
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