皮皮学，免费搜题
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【单选题】
已知如下定义:String s="story";下面那个语句不是合法的( )A.
s+="books";
B.
s=s+100;
C.
int len=s.length;
D.
String t=s+"abc";
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举一反三
【多选题】Types of clinical research include:
A.
Epidemiology, which improves the understanding of a disease by studying patterns, causes, and effects of health and disease in specific groups.
B.
Behavioral, which improves the understanding of human behavior and how it relates to health and disease.
C.
Health services, which looks at how people access health care providers and health care services, how much care costs, and what happens to patients as a result of this care.
D.
Clinical trials, which evaluate the effects of an intervention on health outcomes.
【简答题】The four common types of clinical research include epidemiology, behavioral study, _________________, and _____________.
【简答题】简述美国的电子商务立法的情况
【多选题】Based on the nature and purpose of the study, clinical research includes the following types:
A.
Prevention trials look for better ways to prevent a disease in people who have never had the disease or to prevent the disease from returning. Approaches may include medicines, vaccines, or lifestyle changes.
B.
Screening trials test new ways for detecting diseases or health conditions. Diagnostic trials study or compare tests or procedures for diagnosing a particular disease or condition.
C.
Treatment trials test new treatments, new combinations of drugs, or new approaches to surgery or radiation therapy. Behavioral trials evaluate or compare ways to promote behavioral changes designed to improve health.
D.
Quality of life trials (or supportive care trials) explore and measure ways to improve the comfort and quality of life of people with conditions or illnesses.
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