可屈
趾的肌是 ()
A:
展肌 B:
收肌 C:
短屈肌 D:趾短屈肌 E:足底方肌
创伤对牙周组织的影响是()。
A:单纯、短期的
创伤可引起牙周袋 B:牙动度增加是诊断创伤的惟一指征 C:
创伤可加重牙周炎时牙周袋和牙槽骨吸收 D:
创伤不增加牙松动 E:引起牙龈炎
某井发生卡钻事故,查钻井手册知,本井所用127毫米钻杆的计算系数K为715,经实验,几次拉伸钻杆伸长的总和ΔL为20厘米,所需的拉力差总和P为98千牛,经计算,该井卡点以上钻杆长度L为()米。
A:715 B:1000 C:1430 D:2145
某井发生卡钻事故时,查钻井手册可知,本井所用127mm钻杆的计算系数K=715,经实验,几次拉伸钻杆伸长的总和△L=20cm,所需的拉力差总和T=98kN,经计算,该井卡点以上钻杆长度L=()。
A:715m B:1000m C:1430m D:2145m
为废用牙()
A:X线牙片显示
根分叉处骨质吸收 B:X线牙片显示
骨质致密,骨小梁排列整齐 C:X线牙片显示
牙周膜增宽,牙槽骨吸收至根尖1/3 D:X线牙片显示
牙槽骨疏松,骨小梁排列紊乱,牙槽骨吸收至根尖1/2 E:X线牙片显示
根尖米粒大小阴影
上颌第一磨牙的近中颊尖对着下颌第一磨牙颊沟的近中时,此时的
称为()
A:中性
B:远中
C:近中
D:垂直
E:水平
对乙酰氨基酚的含量测定方法为:取本品约40mg,精密称定,置250mg量瓶中,加0.4%氢氧化钠溶液50ml溶解后,加水至刻度,摇匀,精密量取5ml,置100ml量瓶中,加0.4%氢氧化钠溶液10ml,加水至刻度,摇匀,照分光光度法,在257nm波长处测定吸收度,按C8H9NO2的吸收系数为715计算,即得,若样品称样量为W(g),测得的吸收度为A,测含量百分率的计算式为( )。
A:(A/715)×(250/5)×(1/m)×100% B:(A/715)×(100/5)×250×(1/m)×100% C:A715×(250/5)×(1/m) ×100% D:A715×(100/5)×250×(1/m) ×100% E:(A/715)×(1/m)×100%
There were around two and a half hours between the time the Titanic rammed into the iceberg and its fatal submersion. In this time 705 people were loaded into the twenty lifeboats. There were 473 empty seats available off lifeboats while over 1,500 people drowned. These figures raise two important issues. Firstly, why there were not enough lifeboats to seat every passenger and crew members on board. And secondly, why the lifeboats were not full.
How many people could all the lifeboats hold
A:705 B:473 C:1,178 D:1,500