矫治力来源于患者的口颌系统肌力的矫治器是()。 A.活动矫治器 B.固定矫治器 C.

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问题:

矫治力来源于患者的口颌系统肌力的矫治器是()。

A.活动矫治器

B.固定矫治器

C.功能矫治器

D.磁力矫治器

E.以上都不是

考点:山东住院医师口腔颌面外科口腔颌面外科专业理论口腔颌面外科专业理论题库
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化学与生产生活、社会热点紧密联系.试回答:

(1)2008年9月28日,随着翟志刚、刘伯明、景海鹏三名航天员的平安返回,我国2008年最具代表性和影响力的国家级重大科研实践活动--神舟七号载人航天飞行任务取得圆满成功,实现了我国空间技术发展具有里程碑意义的重大跨越.为防止载人飞船在高温烘烤下表面被氧化,可在载人飞船表面涂上一层纳米硅酸盐涂料.这种涂料应具有哪些性质?(至少答两条)

(2)三聚氰胺(C3N6H6)性状为纯白色单斜棱晶体,无味,快速加热升华,升华温度300℃.溶于热水,低毒.在一般情况下较稳定,但在高温下可能会分解放出氰化物,分解时同时放出不支持燃烧的氮气,因此可作阻燃剂.你能从题中所给信息得到哪些有关三聚氰胺的组成、性质和用途(各写一条)

题型:单项选择题

Jockeys(职业赛马骑师) are the smallest athletes. They are rarely over five feet six, or 120 pounds. The lighter the weight on the horse, the faster it can go.

Riding fast horses on the track is tough on the small jockeys. The jockey doesn’t“sit”on the horse. He leans forward on his legs. The strain is on his thighs(大腿) and calf(小腿) muscles. As jockeys age, their legs“go”first. Jockeys also need arm strength. It’s a strain holding a 1000-pound racehorse.

On muddy days, jockeys get a pounding of mud. The mud comes flying off the hooves(蹄) of the horses in front. “It feels like someone is punching you all over,”says one rider.

And a jockey can be hurt. A jockey can have a leg jammed between two horses. Or it can get caught between horse and the rail. The worst accidents are from falls. A horse may fall on his rider. Or horses behind may trample if he hits the track. In one year about 240 riders are hurt badly. That’s one out of six jockeys.

But the jockeys are well-paid. A jockey keeps about ten percent of the money his horses win. Jacinto Vasquez, a five-foot-three comer, has ridden horses to $7,000,000 in wins in the last eight years, which means he does almost $100,000 a year.

Why do some jockeys do better than others? “It isn’t the way a boy sits on a horse or uses the reins or the whip,”says Conn McCreary. McCreary was a top jockey of the 1950’s. He rode two Kentucky Derby winners. “Most jockeys do this the same. It’s the ‘feel’ he has for the horses.”

“When you come right down to it, it just seems that horses run better for some riders,” McCreary says. “A real good jockey doesn’t lose with the best horse. And sometimes he’ll win with the second or third best.”

Many Latin-American riders, like Jacinto, seem to have the knack. “Maybe it’s because we grew up with horses,”says Jacinto. “Maybe it’s because we like to ride. There was a strike at Aqueduct last year. We, Jorge Velasquez, and Angel Cordero (two other top Latin riders) went to a park. We rented horses, and rode around the bridle path(骑马专用道)!”

小题1:The main idea of Paragraph 1 is about ______________.

A.the size of jockeys.

B.the age of jockeys

C.the size of the horse

D.the speed of the horse小题2:When a jockey is riding a fast horse, he doesn’t __________.

A.really sit on the horse

B.lean forward on his legs

C.use much arm strength

D.get any mud on wet track小题3: The most dangerous problem for a jockey arises __________________.

A.when his leg is jammed between two horses

B.when his clothes are splashed over with mud.

C.when the jockey’s horse falls on the jockey

D.when the jockey is not well paid小题4:A really good jockey can often win a race ____________.

A.only when he rides on the best horse

B.even when he rides the second best horse

C.when he rides on a rented horse

D.if the horse is just a Kentucky Herby小题5: The underlined word “Knack” in the last paragraph probably means__________________.

A.special skill

B.dangerous hobby

C.riding culture

D.excellent horses.

题型:单项选择题

下列属于天然培养基的是()

A.牛肉膏蛋白胨

B.尿素

C.氨基酸

D.麦芽汁培养基

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流体是液体和()的总称。

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对HTML代码“同一个世界
同一个梦想

”描述不正确的是()。

A、文本“同一个世界同一个梦想”自成一个段落。

B、文本“同一个世界同一个梦想”将居中对齐。

C、文本“同一个世界同一个梦想”将分两行显示。

D、文本“同一个世界同一个梦想”中间会有一个空格。

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