某雄黄矿工人,男性,48岁。从事雄黄矿开采20年。近期出现皮肤过度角化、色素沉着及溃

题型:单项选择题

问题:

某雄黄矿工人,男性,48岁。从事雄黄矿开采20年。近期出现皮肤过度角化、色素沉着及溃疡等病变。该工人可能接触了何种毒物

A.铬酸盐

B.石蜡

C.沥青

D.石棉

E.砷化物

考点:公卫执业医师公卫执业医师71
题型:单项选择题

依据《道路交通安全法》,下列说法错误的是( )。

A.机动车、非机动车实行右侧通行
B.根据道路条件和通行需要,道路划分为机动车道、非机动车道和人行道的,机动车、非机动车、行人实行两侧通行
C.道路划设专用车道的,在专用车道内,只准许规定的车辆通行,其他车辆不得进入专用车道内行驶
D.公安机关交通管理部门根据道路和交通流量的具体情况,可以对机动车、非机动车、行人采取疏导、限制通行、禁止通行等措施

题型:单项选择题

某次实验需用0.4 mol/L NaOH溶液480 mL。配制方法如下:

(1)配制该溶液应选用_______________mL容量瓶;   

(2)用托盘天平准确称量__________g 固体NaOH;

(3)将称量好的NaOH固体放在500 mL大烧杯中,倒入约300 mL蒸馏水,用玻璃棒搅拌,使固体全部溶解,待__________________后,将烧杯中的溶液注入容量瓶中;用少量蒸馏水洗涤烧杯          次,洗涤后的溶液一并转入容量瓶,轻轻晃动容量瓶,使溶液混合均匀;向容量瓶中加入蒸馏水,到液面_____________________时,改用__________加蒸馏水至液面最低点与刻度线相切。盖好瓶塞,上下颠倒混合均匀;若在配制过程中出现下列情况,将使所配制的NaOH溶液的浓度偏高的是___________,偏低的是___________,对实验结果没有影响的是___________(填各选项的序号)。

A.所用的NaOH中混有少量Na2O

B.用托盘天平称量一定质量固体NaOH时,所用的小烧杯内壁不太干燥

C.配制溶液所用的容量瓶洗净后没有烘干

D.固体NaOH在烧杯中溶解后,立即将溶液转移到容量瓶内并接着进行后续操作E.转移溶液后,未洗涤烧杯和玻璃棒就直接定容

F.最后确定NaOH溶液体积(定容)时,俯视观察液面与容量瓶刻度线

G.定容摇匀后静止,发现液面低于刻度线,再加蒸馏水至刻度线。

题型:单项选择题

初产妇,足月产,产后2小时,宫底脐上一横指, * * 出血量较多,血色为暗红色。

下列错误的是哪一项()。

A.行子宫按摩

B.乙醚刺激 * *

C.压迫腹主动脉

D.行子宫切除术

E.宫腔内填至纱条

题型:单项选择题

What is distance learning It means that you study on your own, at home or wherever suits you. Recently, the world famous Open University in the United Kingdom has designed a new style of distance learning, which is called (1) . The phrase "Open Learning" means you study (2) . You read course material, work on course activities, and write (3) . The word "Supported" means you have help (4) , the student services staff at regional centres, and centralized areas such as (5) . You can also contact other students through tutorials and (6) , the University’s online conferencing system, and events and clubs organized by (7) . Most distance learning courses use printed paper materials. They also include some (8) materials such as a CD, DVD or video. Many courses have a web site and an (9) . You’ll need access to a computer (10) to make use of these. The Open University can help its students buy a computer and (11) the cost of accessing the Internet.

With most distance learning courses, no (12) are required to study. of course, you have to be aged 18 when your course starts but there is no (13) . Currently the Open University has around (14) undergraduate and more than 30,000 postgraduate students, of which 10,000 have (15) . Nearly all students are studying (16) . About 70 per cent of undergraduate students are in (17) . More than 50,000 students (18) by their employers for their studies. Most distance learning courses (19) . Some of them are even available in other parts of the world. With over 25,000 of its students living outside the UK, the Open University is the (20) that offers distance learning throughout the world.

5()

题型:单项选择题

简述代位继承的概念和条件。

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