科学家从6千8百万年之久的恐龙骨中提取软组织

 

Scientists Extract Soft Tissue from 68-Million-Year-Old Dinosaur¹ Bone

科学家从6千8百万年之久的恐龙骨中提取软组织

 

U.S. scientists have recovered soft tissue from the bones of a nearly 70-million-year-old dinosaur. If it proves to be original tissue not replaced by some other substance, it would be the first to show such material can last more than a few million years and could provide biological insights into the extinct animals.

 

When North Carolina State University biologist Mary Higby Schweitzer looked inside a thigh² bone of a Tyrannosaurus rex excavated³ in the northern state of Montana recently, she was surprised by an unexpected find. Typically, only the hard parts of an animal, like the bones or shell, are preserved. But this dinosaur contained what appears to be well preserved soft tissue inside the bone where the marrow⁴ once was.

 

As Ms. Schweitzer reports in the journal Science, she isolated⁵ the tissue by dissolving the surrounding bone minerals in a weak acid. What remained appears to be blood vessels⁶ and cells still elastic⁷ after 68 million years.

 

Ms. Schweitzer: The thing that was so fascinating for us with this particular dinosaur was that they are transparent⁸, they are flexible. The vessels are such that we can actually manipulate them with our probe. The bone matrix itself, once we removed the minerals from it, is stretchy and flexible. And then, of course, the microstructures that look like cells are preserved in every way. The cellular⁹ extensions are flexible. And they move in solution just like cells preserved in modern bones.

 

For comparison, the researchers analyzed¹⁰ soft tissue from an ostrich¹¹ leg bone because birds are widely believed to have evolved from dinosaurs¹². The dinosaur vessels contained small, reddish-brown dots similar to the nuclei¹³ of cells lining¹⁴ ostrich blood vessels. The Tyrannosaurus rex bone also contained structures that looked virtually identical to ostrich bone cells.

 

There are few examples of prehistoric¹⁵ tissue that are not hard. Such soft material that is preserved is usually not more than a few million years old, such as insects trapped in amber¹⁶ or humans and mammoths in peat or ice. But Ms. Schweitzer says her discovery shows it is now possible to find soft tissue in animals many times older.

 

Ms. Schweitzer: This preservation¹⁸ to this extent, where you still have original flexibility¹⁹ and transparency has not been noted²⁰ in dinosaurs before. So we're pretty excited about the find.

 

If the tissue consists of original material, experts say scientists might be able to extract new information about dinosaurs, especially if they can recover proteins and the genetic²¹ material DNA²².

 

A deputy editor at the journal Science is Robert Hanson.

 

Robert Hanson: That is why the discovery described here is so interesting. These findings thus help us understand preservation in the fossil record and ultimately this study may pave the way towards new insights into dinosaur physiology²³ and biochemistry.

 

But appearances can be deceiving. As a result, the scientists are not claiming their finding is actual proof that the dinosaur tissue is in its native, pristine²⁴ condition. Ms. Schweitzer is conducting laboratory tests to determine whether it is still made of the molecules²⁶ that existed in the living animal, or a pliable²⁷ non-organic compound that has taken their place over the ages.

 

Ms. Schweitzer: Through further chemical analysis we can learn things like, are their protein fragments preserved? If so, how is the protein the same or different from animals that are alive today? As far as DNA goes, we don't know yet. We're doing a lot of stuff in the lab that looks promising²⁸ right now.

 

The North Carolina State University researcher is secretive about those studies, awaiting their final outcome and publication.

 

David McAlary, VOA news, Washington.

 

注释：

soft tissue 软组织

dinosaur [5dainEsC:] n. 恐龙

thigh [Wai] n. 大腿

Tyrannosaurus rex [tirAnE5sC:rEs,reks] n. 暴龙

marrow [5mArEu] n. 髓，骨髓

elastic [i5lAstik] adj. 弹性的

probe [prEub] n. 探针，探测器

microstructure [5maikrEu5strQktFE] n. 微观结构，显微结构

ostrich [5CstritF] n. 鸵鸟

amber [5AmbE] n. 琥珀

mammoth¹⁷ [5mAmEW] n. [古生]猛犸，毛象

peat [pi:t] n. 泥煤，泥炭块

biochemistry [5baiEu5kemistri] n. 生物化学

molecule²⁵ [5mClikju:l] n. [化]分子，些微

pliable [5plaiEbl] adj. 柔软的，圆滑的，柔韧的

1 dinosaur   

n.恐龙

参考例句：

• Are you trying to tell me that David was attacked by a dinosaur?你是想要告诉我大卫被一支恐龙所攻击？
• He stared at the faithful miniature of the dinosaur.他凝视著精确的恐龙缩小模型。

2 thigh   

n.大腿；股骨

参考例句：

• He is suffering from a strained thigh muscle.他的大腿肌肉拉伤了，疼得很。
• The thigh bone is connected to the hip bone.股骨连着髋骨。

3 excavated   

v.挖掘( excavate的过去式和过去分词 )；开凿；挖出；发掘

参考例句：

• The site has been excavated by archaeologists. 这个遗址已被考古学家发掘出来。
• The archaeologists excavated an ancient fortress. 考古学家们发掘出一个古堡。 来自《简明英汉词典》

4 marrow   

n.骨髓；精华；活力

参考例句：

• It was so cold that he felt frozen to the marrow. 天气太冷了，他感到寒冷刺骨。
• He was tired to the marrow of his bones.他真是累得筋疲力尽了。

5 isolated   

adj.与世隔绝的

参考例句：

• His bad behaviour was just an isolated incident. 他的不良行为只是个别事件。
• Patients with the disease should be isolated. 这种病的患者应予以隔离。

6 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

7 elastic   

n.橡皮圈，松紧带；adj.有弹性的；灵活的

参考例句：

• Rubber is an elastic material.橡胶是一种弹性材料。
• These regulations are elastic.这些规定是有弹性的。

8 transparent   

adj.明显的，无疑的；透明的

参考例句：

• The water is so transparent that we can see the fishes swimming.水清澈透明，可以看到鱼儿游来游去。
• The window glass is transparent.窗玻璃是透明的。

9 cellular   

adj.移动的；细胞的，由细胞组成的

参考例句：

• She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
• Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。

10 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

11 ostrich   

n.鸵鸟

参考例句：

• Ostrich is the fastest animal on two legs.驼鸟是双腿跑得最快的动物。
• The ostrich indeed inhabits continents.鸵鸟确实是生活在大陆上的。

12 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》

13 nuclei   

n.核

参考例句：

• To free electrons, something has to make them whirl fast enough to break away from their nuclei. 为了释放电子，必须使电子高速旋转而足以摆脱原子核的束缚。
• Energy is released by the fission of atomic nuclei. 能量是由原子核分裂释放出来的。

14 lining   

n.衬里，衬料

参考例句：

• The lining of my coat is torn.我的外套衬里破了。
• Moss makes an attractive lining to wire baskets.用苔藓垫在铁丝篮里很漂亮。

15 prehistoric   

adj.（有记载的）历史以前的，史前的，古老的

参考例句：

• They have found prehistoric remains.他们发现了史前遗迹。
• It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。

16 amber   

n.琥珀；琥珀色；adj.琥珀制的

参考例句：

• Would you like an amber necklace for your birthday?你过生日想要一条琥珀项链吗？
• This is a piece of little amber stones.这是一块小小的琥珀化石。

17 mammoth   

n.长毛象；adj.长毛象似的，巨大的

参考例句：

• You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。
• Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。

18 preservation   

n.保护，维护，保存，保留，保持

参考例句：

• The police are responsible for the preservation of law and order.警察负责维持法律与秩序。
• The picture is in an excellent state of preservation.这幅画保存得极为完好。

19 flexibility   

n.柔韧性，弹性，（光的）折射性，灵活性

参考例句：

• Her great strength lies in her flexibility.她的优势在于她灵活变通。
• The flexibility of a man's muscles will lessen as he becomes old.人老了肌肉的柔韧性将降低。

20 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

21 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

22 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

23 physiology   

n.生理学，生理机能

参考例句：

• He bought a book about physiology.他买了一本生理学方面的书。
• He was awarded the Nobel Prize for achievements in physiology.他因生理学方面的建树而被授予诺贝尔奖。

24 pristine   

adj.原来的，古时的，原始的，纯净的，无垢的

参考例句：

• He wiped his fingers on his pristine handkerchief.他用他那块洁净的手帕擦手指。
• He wasn't about to blemish that pristine record.他本不想去玷污那清白的过去。

25 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

26 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

27 pliable   

adj.易受影响的；易弯的；柔顺的，易驾驭的

参考例句：

• Willow twigs are pliable.柳条很软。
• The finely twined baskets are made with young,pliable spruce roots.这些编织精美的篮子是用柔韧的云杉嫩树根编成的。

28 promising   

adj.有希望的，有前途的

参考例句：

• The results of the experiments are very promising.实验的结果充满了希望。
• We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。