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问题 多项选择题

关于二次谐波的接收及图像质量的改善，叙述正确的有（）。

A.接收时提取2f0的谐波回声信号（自然组织与造影剂谐波信号）

B.通过锐利接收滤波器提取纯净谐波成分，消除基波与二次谐波重叠成分

C.谐波可以明显改善图像质量，是因谐波频率比基波频率高

D.消除近场伪像干扰，包括表层腹壁和旁瓣伪像

E.消除远场混响，使紊乱和模糊影像被消除

答案

参考答案：A, B, D

问答题

Turkey’s Bodrum peninsula is different. The tourist boom in this part of the world (1) turned some small villages into resorts yet left neighbouring beaches undisturbed, making it quite (2) southern France or the Spanish Coasts where few stretches of coastline are undevelopeD．
The (3) for this happy set of circumstances is simple. For thousands of years, travel here (4) easier by boat than by lanD．So when mass tourism arrived in the (5) 1980s, there was no coast road for ribbon development to follow. So the peninsula, just (6) hour from Bodrum airport, has not become one long littoral of resort.
The building (7) new hotels has mainly been confined to places easily reached by then relatively (8) roads. Such ease of access has made Gumbet, near Bodrum, a busy resort, while the little fishing village of Gumusluk, 12 miles further west and only recently reachable by (9) , remains tranquil and undisturbeD．
It’s worth thinking carefully about location when planning a family (10) on the peninsulA．Choose a place that is centrally located, preferably out of earshot (11) Bodrum town’s "lively"—which means nosy—nightlife, and you can then use (12) area’s comfortably small scale to your advantage. Today’s new roads mean most places can (13) reached in under an hour by taxi or the ubiquitous dolmus-minibus.
The (14) of facilities at the Tamarisk Beach Hotel near the small village of Ortakent makes (15) a good base. The family-run hotel—rooms and suites are in two-storey buildings (16) by palm trees and flowers in terracotta pots—sits above its own sandy (17) beach, shaded by tamarisk trees and sheltered by nearby islands.
The hotel is (18) child-friendly, too. Children, from infants up to young teenagers, can take part in a (19) of games and activities that include tuition in windsurfing, dinghy (20) catamaran sailing.

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单项选择题

小儿阑尾炎的诊断中，不正确的做法是（）。

A.争取患儿的合作，必要时可使用镇静剂

B.检查腹部时，最后检查右下腹

C.为减轻患儿痛苦，不必反复检查

D.白细胞计数上升不明显不能否定诊断

E.部分病例压痛可不在右下腹
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