The enormous number of sperms produced daily and over the lifetime of mammals requires a stable source of stem cells that give rise to progenitor cells that proceed through spermatogenesis. Spermatogenic stem cells develop from primitive germ cells that occupy the developing gonad. A transplantation assay was developed for the spermatogenic stem cells, and it remains the only functional measure of authentic stem cells in the testis. Somatic cells comprise a "niche" environment that is essential for the maintenance of stem cell activity. Dividing progenitor cells have intercellular bridges and form syncytia with 2, 4, 8, or 16 cells. Fragmentation of these syncytia may allow some progenitor cells to occupy "niches" and function as stem cells, but this notion requires further investigation. Spermatogenic stem cells can be maintained in culture and are influenced by a number of growth factors. Thus far, the ultimate differentiation of cultured stem cells into functional gametes has not been demonstrated with any efficiency and reproducibility. The ability to maintain spermatogenic stem cells in culture and to induce differentiation into haploid cells and sperm could have many important implications for human medicine.
This research output has an Altmetric Attention Score of 4. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 04 October 2014.
All research outputs
#6,915,761
of 22,681,577 outputs
Outputs from Stem Cells
#1,942
of 3,894 outputs
Outputs of similar age
#75,322
of 280,092 outputs
Outputs of similar age from Stem Cells
#12
of 33 outputs
Altmetric has tracked 22,681,577 research outputs across all sources so far. This one has received more attention than most of these and is in the 68th percentile.
So far Altmetric has tracked 3,894 research outputs from this source. They typically receive more attention than average, with a mean Attention Score of 8.7. This one is in the 48th percentile – i.e., 48% of its peers scored the same or lower than it.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 280,092 tracked outputs that were published within six weeks on either side of this one in any source. This one has gotten more attention than average, scoring higher than 71% of its contemporaries.
We're also able to compare this research output to 33 others from the same source and published within six weeks on either side of this one. This one has gotten more attention than average, scoring higher than 57% of its contemporaries.
