The stem cells that could potentially allow us to regenerate are the pluripotent ones. Since adult mammals basically don't have any, we can't regenerate.
That's what you're missing. Well, one of the things.
" stem cell.[4]
Totipotent (a.k.a omnipotent) stem cells can differentiate into embryonic and extraembryonic cell types. Such cells can construct a complete, viable, organism.[4] These cells are produced from the fusion of an egg and sperm cell. Cells produced by the first few divisions of the fertilized egg are also totipotent.[5]
Pluripotent stem cells are the descendants of totipotent cells and can differentiate into nearly all cells,[4] i.e. cells derived from any of the three germ layers.[6]
Multipotent stem cells can differentiate into a number of cells, but only those of a closely related family of cells.[4]
Oligopotent stem cells can differentiate into only a few cells, such as lymphoid or myeloid stem cells.[4]
Unipotent cells can produce only one cell type, their own,[4] but have the property of self-renewal which distinguishes them from non-stem cells (e.g. muscle stem cells).
Embryonic
Main article: Embryonic stem cell
Embryonic stem cell lines (ES cell lines) are cultures of cells derived from the epiblast tissue of the inner cell mass (ICM) of a blastocyst or earlier morula stage embryos.[9] A blastocyst is an early stage embryo—approximately four to five days old in humans and consisting of 50–150 cells. ES cells are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm and mesoderm. In other words, they can develop into each of the more than 200 cell types of the adult body when given sufficient and necessary stimulation for a specific cell type. They do not contribute to the extra-embryonic membranes or the placenta.
Fetal
Fetal stem cells are primitive cell types found in the organs of fetuses.[18] The classification of fetal stem cells remains unclear and this type of stem cell is currently often grouped into an adult stem cell. However, a more clear distinction between the two cell types appears necessary.
[edit] Adult
Main article: Adult stem cell
Stem cell division and differentiation. A - stem cell; B - progenitor cell; C - differentiated cell; 1 - symmetric stem cell division; 2 - asymmetric stem cell division; 3 - progenitor division; 4 - terminal differentiationThe term adult stem cell refers to any cell which is found in a developed organism that has two properties: the ability to divide and create another cell like itself and also divide and create a cell more differentiated than itself. Also known as somatic (from Greek Σωματικóς, "of the body") stem cells and germline (giving rise to gametes) stem cells, they can be found in children, as well as adults.[19]
Pluripotent adult stem cells are rare and generally small in number but can be found in a number of tissues including umbilical cord blood.[20
http://en.wikipedia.org/wiki/Stem_cell
I am quoting above different type of stem cells. Other decendant lines to plripotent cells can also do much.
None of which allow us to regenerate lost limbs. None of which are in circulation or take part in the normal healing process or in fighting disease.
Links suggest few stem cells remain present in circulation. Probably, we have some miss or weaknesses(inherited or acquired due to our opted lifestyle & practices), that we can't heal completely which stem cell therapiest are trying. Cloning is other issue where every thing can be renewed even without stem cells.
No they don't. At least, not such painfully wrong ones.
You are not presenting coloured stones. You are presenting bits of bark, leaves, dead insects and so on, and asking us each time if you've found a gem. We explain to you that you have not only not found a gem, you haven't even found a stone, and off you go again.
Here, Kumar, this is what your thinking leads to:
Stem Cell Tourist Dies From Treatment In ThailandThe people researching stem cells are mostly good, honest scientists. The people pushing stem cell therapies are all too often outright frauds - and murderers. (Though it's likely this unfortunate woman would have died from her disease anyway, since autoimmune diseases can be very difficult to treat.)
At least I am trying by brain storming. It is wasteful hear to talk about delicate healing systems.
Thanks for link. I shall go through later.