Vaccinations were first used in the year 1796.
HIV is the virus that causes <span>acquired immune deficiency syndrome (AIDS)</span>
<span>Weight
gain occurs either through intentional or unintentional way. Intentional way of
weight gain is where an individual is over eating or having meals that have
high calories which makes a person obese. The unintentional way of weight gain
is when an individual is experiencing medical problems like urinary problems,
endocrine system problems like hormonal imbalances and the likes, due to
stress, etc. An individual who are having a weight gain problem should consult
a doctor immediately to check the cause of the weight gain and to solve the
problem. </span>
Answer:
Human subject research is systematic, scientific investigation that can be either interventional (a "trial") or observational (no "test and Human subject research can be either medical (clinical) research or non-medical (e.g., social science) research.
