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问题 单项选择题

磺胺类药物对于二氢叶酸合成酶的影响属于

A．反竞争抑制
B．底物抑制
C．竞争抑制
D．非竞争抑制
E．共价修饰调节

答案

参考答案：C

解析：磺胺类药物与对氨基苯甲酸的结构类似，是二氢叶酸合成酶的竞争性抑制剂。答案选C。

填空题


A patrol team of sea lions and dolphins featured in a large-scale military exercises being conducted by the U. S. and its allies in the Pacific Ocean. The machine (1) took part in simulated mine recovery and mine detection missions during the biennial Rim of the Pacific Exercise (RIMPAC) war games. The (2) started on June 19 and will run (3) Friday.
"There are a number of mechanical systems that work in those areas. (4) high-tech gadgets deployed by the military can’t (5) the natural skills of dolphins and lions," said Tom Lapuzza, spokesman for UN Navy’s Marine Mammal Program. Sea lions have "incredible good underwater (6) " and can dive down to 300 meters to catch a recovery line to a mine, he said. Dolphins use sonar to (7) mine.
Human beings have a long (8) of training animals to join the military. Horses have been the most widely-used animals (9) the recorded history of (10) . In early times, horses were used to (11) chariots or to (12) armored forces. With the development of modem weapons and motorized (13) , the use of horses for military purposes fell into (14) . (15) , horses were still used (16) by the German army during World War II for transporting (17) and equipment, including artillery.
During World War II, (18) with explosives strapped to their backs were used as anti-tank weapons. In other (19) , they were used for detecting mines. Some dogs were also used as messengers.
Other animals have also (20) in the military. Recorded history shows the use of elephants for military purposes as early as 1,100 B. C.. They were employed during World War II by both the Japanese army and the (21) .
There are records showing that over 100,000 reindeer were used by Finland to tow sleds during World War II. They carried the (22) to hospitals, brought supplies to the troops and moved heavy anti-tank weapons. It is well documented that oxen have been (23) used in war as improvised beasts of burden. During World War II, spiders were employed by the Allies to spin silk for (24) in cross-hairs on bomb scopes and other optical instruments. People also are finding that Vampire bats’ ability to use echolocation is very interesting as we (25) to learn how it works and it may benefit the army.
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单项选择题

对注射剂的质量检查叙述不正确的是

A．检查降压物质以猫为实验动物

B．澄明度检查应在黑色背景，20W照明荧光灯光源下用目检视

C．中国药典规定热原检查采用家兔法

D．鲎试剂法是利用鲎的变形细胞溶解物与内毒素间的胶凝反应

E．鲎试剂法检查热原无需做阳性对照和阴性对照
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