射野输出因子(OUT)是描述射野输出剂量随射野增大而增加的关系,它定义为()。 A.

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问题:

射野输出因子(OUT)是描述射野输出剂量随射野增大而增加的关系,它定义为()。

A.射野在空气中的输出剂量与参考射野在空气中的输出剂量之比

B.射野在模体中的输出剂量与参考射野在模体中的输出剂量之比

C.射野在空气中的输出剂量与参考射野在模体中的输出剂量之比

D.射野在模体中的输出剂量与参考射野在空气中的输出剂量之比

E.参考射野在空气中的输出剂量与射野在空气中的输出剂量之比

考点:山东住院医师肿瘤放疗科Ⅱ阶段专业理论专业理论题库
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下图1表示生态系统中各成分之间的联系,C表示分解者。图2为一定时间内某一生态系统中的几个种群数量变化曲线,请据图回答:

(1)图1中能构成群落的是____________,图2中的甲相当于图1中的_____________。

(2)种群丙在b、c、d、e四个时期中种内斗争最激烈的是期_____________。

(3)某地区因环境污染造成E中出现大量白化苗,则F、D、B的数量将会____________。为了提高E的产量,农民在田问施放某种物质,该物质能够吸引大量昆虫为其传粉,这是__________信息传递在农业生产上的应用。如果污染加重,会使农田变为__________。若干年后,又出现了新的生物群落,这种演替称为________。

(4)图3是某人工鱼塘生态系统能量流动过程中部分环节涉及的能量值,有机物输入均表示同化量(单位为103kJ/m2·a)。回答下列有关问题:

Ⅰ.图中②代表的能量主要以___________的形式贮存;能量从该生态系统的第一营养级到第二营养级的传递效率为_________________。

Ⅱ.试分析图中植食动物、肉食动物和顶位肉食动物随营养级的升高需要的有机物输入越来越多的原因:______________。

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女,25岁。2年以来和丈夫吵架或遇到不高兴的事后,即出现四肢强直和抽搐样表现。发作时能听清楚家人的呼唤但不予回答。无唇舌咬伤和大小便失禁,瞳孔无散大,对光反射存在。该患者最可能的诊断是()。

A.癫痫

B.创伤后应激障碍

C.癔症

D.神经衰弱

E.适应性障碍

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救生照明线适用于浓烟、地下室、无照明场所和水下等场所的作业。

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B Egyptian Villages 埃及村落

Most of the inhabitants live in mud-brick homes, their (1)  walls insulating against the afternoon heat. Flat roofs, exposed (2)  the northern evening breezes, serve as cool sleeping (3)  as well as storage areas. Villagers plaster the outer walls (4)  often trim them in blue, a color they believe (5)  off the evil eye. As a man becomes richer, (6)  can add a second story to his house perhaps (7)  his married son. Those villagers who have made the (8)  to Mecca paint the legend of their trip on (9)  outer walls of their homes. Such hajj houses, along (10)  the mosques, are the most distinguished buildings in a (11)

Some villagers build ornate pigeon coops close to their (12) , using the birds as food and their droppings to (13)  crops. Many houses still have dirt floors and lack (14)  or running water; women with jars balanced on their (15)  make the trek to the community well, and children donkeys haul the (16)  liquid in jerry cans.

All (17)  said, government sponsored building programs have also brought newer (18)  residences and utilities to some villages, particularly those outside (19)  Nile Valley in the Oases and the Red Sea (20)  areas.

4.()

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AgCl、Hg2Cl2和PbCl2三种沉淀中,只有AgCl可以溶解在NH3·H2O中。( )

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