2018年公共英語(yǔ)五級(jí)閱讀理解模擬題（13）

　　公共英語(yǔ)五級(jí)閱讀理解模擬題

　　At 18, Ashanthi DeSilva of suburban Cleveland is a living symbol of one of the great intellectual achievements of the 20th century. Born with an extremely rare and usually fatal disorder that left her without a functioning immune system (the "bubble-boy disease", named after an earlier victim who was kept alive for years in a sterile plastictent), she was treated beginning in 1990 with a revolutionary new therapy that sought to correct the defect at its very

　　source, in the genes of her white blood cells. It worked. Although her last gene-therapy treatment was in 1992, she is completely healthy with normal immune function, according to one of the doctors who treated her, W. French Anderson of the University of Southern California. Researchers have long dreamed of treating diseases from hemophilia to cancer by replacing mutant genes with normal ones. And the dreaming may continue for decades more.

　　"there will be a gene-based treatment for essentially every disease, " Anderson says, "within 50 years. "

　　It' s not entirely clear why medicine has been so slow to build on Anderson' s early success. The National Insti- tutes of Health budget office estimates it will spend $ 432 million on gene-therapy research in 2005, and there is no shortage of promising leads. The therapeutic genes are usually delivered through viruses that don' t cause human disease. "The virus is sort of like a Trojan horse, " says Ronald Crystal of New York Presbyterian/Weill Cornell Medical College. "The cargo is the gene. "

　　At the University of Pennsylvania' s Abramson Cancer Center, immunologist Carl June recently treated HIV patients with a gene intended to help their cells resist the infection. At Cornell University. researchers are pursuing gene-based therapies for Parkinson' s disease and a rare hereditary disorder that destroys children" s brain cells. At Stanford University and the Children' s Hospital of Philadelphia, researchers are trying to figure out bow to help pa- tients with hemophilia who today must inject themselves with expensive clotting drugs for life. Animal experiments have shown great promise.

　　But somehow, things get lost in the translation from laboratory to patient. In human trials of the hemophilia treatment, patients show a response at first, but it fades over time. And the field has still not recovered from the set- back it suffered in 1999, when Jesse Gelsinger, an 18-year-old with a rare metabolic disorder, died after receiving an experimental gene therapy at the University of Pennsylvania. Some experts worry that the field will be tarnished fur- ther if the next people to benefit are not patients but athletes seeking an edge. This summer, researchers at the Salk Institute in San Diego said they had created a "marathon mouse" by implanting a gene that enhances running ability;already, officials at the World Anti-Doping Agency are preparing to test athletes for signs of "gene doping". But the principle is the same, whether you' re trying to help a healthy runner run faster or allow a muscular-dystrophy patient to walk. "Everybody recognizes that gene therapy is a very good idea, " says Crystal. "And eventually it' s going to work. ""

　　56. The case of Ashanthi Desilva is mentioned in the text to

　　A. show the promise of gene-therapy

　　B. give an example of modern treatment for fatal diseases

　　C. introduce the achievement of Anderson and his team

　　D. explain how gene-based treatment works

　　57. Anderson' s early success has ____

　　A. greatly speeded the development of medicine

　　B. brought no immediate progress in the research of gene-therapy

　　C. promised a cure to every disease

　　D. made him a national hero

　　58. Which of the following is true according to the text?

　　A. Ashanthi needs to receive gene-therapy treatment constantly.

　　B. Despite the huge funding, gene researches have shown few promises.

　　C. Therapeutic genes are carded by harmless viruses.

　　D. Gene-doping is encouraged by world agencies to help athletes get better scores.

　　59. The word "tarnish" (line 4, paragraph 4) most probably means __

　　A. affect

　　B. warn

　　C. trouble

　　D. stain

　　6O. From the text we can see that the author seems

　　A. optimistic

　　B. pessimistic

　　C. troubled

　　D. uncertain

　　答案及解析

　　56.A【解析】文章第一句話(huà)對(duì)用基因療法治療Ashanthi所患罕見(jiàn)疾病的成功給予了很高的評(píng)價(jià)，并在第一段末指出醫(yī)生們對(duì)基因療法寄予了極高的期望。因此正確答案為A。

　　57.B【解析】文章第二段一開(kāi)頭就說(shuō)：…It S not entirely clear whv medi—cine has been SO slow to build on Anderson’S early Success.”從時(shí)間上來(lái)看，Anderson采用基因療法的成功嘗試已經(jīng)是l990年的事情了，兩相對(duì)照，可見(jiàn)他的成功沒(méi)有讓醫(yī)學(xué)加速發(fā)展。因此正確答案為B。

　　58.c【解析】文章第二段對(duì)于基因治療的方式的解釋是用于治療的基因通過(guò)“viruses that don’t cause human disease”進(jìn)入體內(nèi)，就好像“特洛伊木馬”一樣，由此可見(jiàn)，這些病毒是無(wú)害的。因此正確答案為C。

　　59.D【解析】第四段提到基因療法遭受的一起挫折——一個(gè)病人因接受基因療法而死亡;接著講專(zhuān)家擔(dān)心運(yùn)動(dòng)員利用基因在比賽中作弊會(huì)進(jìn)一步tarnish這一領(lǐng)域，從上下文邏輯推理，應(yīng)該是“有損，玷污”這一類(lèi)的意思，因此正確答案為D。

　　60.A【解析】作者的態(tài)度從文章第一句話(huà)和最后一句話(huà)就可以明顯判斷出來(lái)。第一句話(huà)說(shuō)基因療法是20世紀(jì)的偉大成就之一，最后一句話(huà)說(shuō)“Everybody recogllizes that gene therapy is a very good idea”，由此可見(jiàn)作者對(duì)基因療法持積極樂(lè)觀的態(tài)度。因此正確答案為A。