胆绞痛、发热、黄疸见于（） A．胰头癌 B．慢性胆囊炎 C．急性胰腺炎 D．急性胆囊

心房颤动发生后患者心排血量下降的比例是（）

A.50%

B.30%～50%

C.30%

D.25%

E.20%

一个游泳池长50米，宽25米，高3米，如果往游泳池中放2.5米深的水，一共放水______立方米，合______立方分米，合______升．

阅读理解。

      People from East Asia tend to have more difficulty than those from Europe in distinguishing facial

expressions-and a new report published online in Current Biology explains why.

      Rachael Jack, University of Glasgow researcher, said that rather than scanning evenly (均匀地) across

a face as Westerners do, Easterners fix their attention on the eyes.

      "We show that Easterners and Westerners look at different face features to read facial expressions,"

Jack said. "Westerners look at the eyes and the mouth in equal measure, whereas Easterners favor the eyes

and neglect (忽略) the mouth."

      According to Jack and her colleagues, the discovery shows that human communication of emotion is

more complex than previously believed. As a result, facial expressions that had been considered universally

recognizable cannot be used to reliably convey emotion in cross-cultural situations.

      The researchers studied cultural differences in the recognition of facial expressions by recording the

eye movements of 13 Western Caucasian and 13 East Asian people while they observed pictures of expressive

faces and put them into categories: happy, sad, surprised, fearful, disgusted, angry, or neutral. They compared

how accurately participants read those facial expressions using their particular eye movement strategies.

      It turned out that Easterners focused much greater attention on the eyes and made significantly more errors

than did Westerners. "The cultural difference in eye movements that they show is probably a reflection of

cultural difference in facial expressions," Jack said. "Our data suggest that whereas Westerners use the whole