问题 单项选择题 A型题

关于起搏器的工作参数的表述,正确的是()。

A.AV间期通常不能被程控调整

B.起搏器的输出电压通常设定为起搏阈值的2~3倍

C.感知电极的极性设定为单极时可减少外界电磁干扰

D.当起搏器输出电压固定时,脉宽越宽输出能量越小

E.通常将起搏设定为双极,感知设定为单极

答案

参考答案:B

解析:为确保有效起搏,起搏器的输出电压通常设定为起搏阈值的2~3倍。起搏与感知均可设定为单极或双极,通常将起搏设定为单极,感知设定为双极,这既可保证心电图的起搏脉冲幅度较高,又可减少外界电磁场干扰。

单项选择题 A1/A2型题
问答题

Vilhelm Hammershoi has been a well-kept secret since his death in 1916. All his best- known paintings are of household interiors that are drained of color and tell no stories. 46. His windows cannot be seen through, his doors cannot be opened and the figures produce no element of vitality into the rooms. Hammershoi is defiantly inscrutable; the mood is melancholic and enigmatic, but the paintings are oddly compelling. Quite why, no one seems sure.
Of the 71 paintings in a new exhibition in London, 21 come from his native Copenhagen, 15 from other Scandinavian collections and 20 from private collections, principally Danish. Hammershoi’s focus was not as narrow as this show might suggest, but to see his nudes it is necessary to visit the Statens Museum for Kunst in Denmark. He did some fine, if bleak, landscapes too, but it was the interiors that sold in his lifetime, and he is best remembered for paintings of the sun shining through curtainless window-panes, casting shadows on carpetless floors. 47.Anxious to transform the prosaic into the romantic, his admirers speak of a poet of light and the poetry of silence.
Hammershoi himself was guileless. 48."What makes me choose a motif are the lines, what I like to call the architectural context of an image," he said in 1907. Light was also very important, but it was lines, he insisted, that had the greatest significance for him. His wife, Ida, makes appearances in the empty rooms, but she is usually painted from the back, with the emphasis on the bare nape of her neck. The heroic figures are white doors and windows, and tables, chairs, a piano and a sofa. No painter can have got so much pleasure from painting brown furniture. One work, titled "Interior with a Woman at a Sewing Table", is a symphony of three shades of shiny brown.
Hammershoi was influenced by Vermeer and the 17th-century Dutch genre painters and by Caspar David Friedrich, a German, but there is no one like him. His work shows traces of an unexpected subversive sense of humor. 49.Felix Kramer, the show’s curator, identifies irregularities, for example, that create an almost surreal quality: a piano with two legs, table legs casting shadows in different directions, chests of drawers with no knobs or handles. Even some of Hammershoi’s admirers wonder what it all means.
50.Trying to pin Hammershoi down is as profitless as Waiting for Godot. However, the new exhibition at the Royal Academy of Arts might encourage some excitement in the marketplace. The highest price made by a Hammershoi interior is £ 520,000 ($1 million) in 2006 and the price boom in the auction houses is passing him by. Perhaps the secret of Hammershoi has been kept a bit too well.