患儿，1岁。发热1d，全身见散在细小淡红色皮疹，喷嚏，流涕，偶有咳嗽，精神不振，胃纳

下列关于疫苗的叙述正确的是 [ ]

A．所有的疫苗都是用杀死的病原体制成的

B．所有的疫苗都是用减毒的病原体制成的

C．疫苗可使人体产生抗体

D．一种疫苗能抵抗多种病原体

肥达反应中，若"O"正常而"H"高，可能是（）

A.有过伤寒病史

B.以上都不对

C.感染早期

D.交叉反应

E.其他沙门菌感染

病历摘要：女，17岁。昨晚与家人吵架后，今晨起床四肢无力，行走不能，抬手困难，送院急诊。无头痛、头晕，无呼吸困难。既往甲亢病史3年，已治愈停药1年；2周前腹泻多次，外院门诊治疗好转。查体：T36.7℃，神清，对答切题，语利，颅神经（-），四肢肌张力低，肌力近端Ⅱ级，远端Ⅲ级，腱反射迟钝，病理征（-），四肢感觉麻木。

Guillain-barre综合征的诊断标准和临床治疗原则有以下哪些？（）

A.病前1～4周有感染史，急性或亚急性起病

B.四肢对称性软瘫

C.末梢型感觉障碍

D.F波或H反射延迟，CSF蛋白细胞分离是早期诊断的重要依据

E.颅神经受累，以眼外肌麻痹最常见，其次为球麻痹

F.呼吸肌麻痹是GBS的主要死因，缺氧时应接呼吸机辅助呼吸

G.皮质类固醇治疗效果最佳，及早使用

H.血浆交换可缩短病程，减少并发症

一方控制、共同控制另一方或对另一方施加重大影响，以及两方或两方以上同受一方控制、共同控制或重大影响的，构成关联方。 ( )

There were two widely divergent influences on the early development of statistical methods. Statistics had a mother who was dedicated to keeping orderly records of governmental units (state and statistics come from the same Latin root, status) and a gentlemanly gambling father who relied on mathematics to increase his skill at playing the odds in games of chance. The influence of the mother on the offspring, statistics, is represented by counting, measuring, describing, tabulating, ordering, and the taking of censuses—all of which led to modem descriptive statistics. From the influence of the father came modem inferentical statistics, which is based squarely on theories of probability.

Descriptive statistics involves tabulating, depicting, and describing collections of data. These data may be either quantitative, such as measures of height, intelligence, or grade level—variables that are characterized by an underlying continuum or the data may represent qualitative variable, such as sex, college major, or personality type.

Large masses of data must generally undergo a process of summarization or reduction before they are comprehensible. Descriptive statistics is tool for describing or summarizing or reducing to comprehensible form the properties of an otherwise unwieldy mass of data.

Inferential statistics is a formalized body of methods for solving another class of problems that present great difficulties for the unaided human mind. This general class of problems characteristically involves attempts to make predictions using a sample of observations. For example, a school superintendent wishes to determine the proportion of children in a large school system who come to school without breakfast, have been vaccinated for flu, or whatever. Having a little knowledge of statistics, the superintendent would know that it is unnecessary and inefficient to question each child; the proportion for the entire district could be estimated fairly accurately from a sample of as few as 100 children. Thus, the purpose of inferential statistics is to predict or estimate characteristics of a population from knowledge of the characteristics of only a sample of the population.

Which of the following is true of descriptive statistics（）

A. It leads to increased variability

B. It solves all numerical problems

C. It simplifies unwieldy masses of data

D. It changes qualitative variables to quantitative variables