+ Symbol: Search engine math
illness + disease + “stem cell therapy”
risk + “stem cell therapy”
“umbilical cord blood” + “stem cell therapy”
- Symbol: Search engine math
“stem cell therapy” –ethical –controversy
“stem cell therapy” –debates
“stem cell applications” –embryonic
Phrases
“bone marrow transplant therapy”
“ethical issues in stem cell research” –United States + Europe
“stem cell risks” + women
Boolean Operators
(stem cell therapy) AND (childhood leukemia)
(pluripotent stem cell therapy) OR (adults)
(embryonic stem cell therapy) NOT (United States research)
(ethical stem cell issues) AND (international)
(new perspectives in human stem cell application) OR (children)
(stem cell diabetes) OR (adults)
(stem cell spinal cord injuries) NOT (children)
