Related by context. Frequent words. (Click for all words.) 84 embryonic stem cells 72 adult stem cells 72 stem cells 70 embryonic stem cell 70 human embryos 69 human embryonic stem 67 stem cell 66 embryo 65 cloned embryos 65 embryos 65 iPS cells 65 induced pluripotent stem cells 64 ES cells 63 therapeutic cloning 62 Embryonic stem cells 62 stem cells derived 61 stem cell research 60 somatic cell nuclear 59 embryonic 59 pluripotent 58 stem cell therapies 57 Stem cells 56 reproductive cloning 56 human cloning 55 adult stem cell 55 fertilized egg 54 neural stem cells 54 Stem cell 54 cloning 53 oocytes 52 fertilized eggs 52 islet cells 51 stem cell therapy 51 gene therapy 49 Harvard Stem Cell 49 mesenchymal stem cells 49 progenitor cells 49 Stem Cell Research 48 bone marrow transplants 47 mammalian cells 47 frozen embryos 47 fertility treatments 46 ovarian tissue 46 genetically engineered 46 regenerative medicine 46 vitro fertilization 46 Stem Cells 46 Stem Cell 46 synthetic biology 46 vitro fertilization IVF 45 assisted reproduction 45 insulin producing 45 stem cell biology 45 islet cell 45 genetic abnormalities 44 miRNAs 44 stem cell transplantation 44 cells 44 genetically modified 44 stem cell transplants 44 PGD 44 genetic manipulation 44 cannabinoids 43 Cloning 43 IVF 43 bone marrow transplantation 43 quantum computers 43 telomerase 43 grafts 43 genetically identical 43 genetic modification 43 Advanced Cell 43 ovary 43 zebrafish 43 infertile couples 43 umbilical cord blood 43 transgenic 42 pancreatic 42 Geron 42 transplantation 42 vitro 42 quantum dots 42 fibroblasts 42 umbilical cords 42 malignant tumors 42 reprogramming 42 flu vaccines 42 sperm 42 microRNAs 42 genetically altered 42 RNA molecules 42 retrovirus 42 immunotherapies 42 organ transplants 42 cloned 42 miRNA 42 biomedical research 42 fetuses 41 tumors 41 knockout mice 41 RNA interference