We also tried PEA-10 cells (Lrp-1 +/-) and PEA-13 cells (Lrp-1 -/-), but encountered the difficulty that currently no PEDF-related assay has been established in these cellular models.
When States attempted to value railroad or telegraph companies for property tax purposes, they encountered the difficulty that what makes such a business valuable is the enterprise as a whole, rather than the track or wires which happen to be located within a State's borders.
As a young man, Wigglesworth had a reputation as a brilliant but uncompromising character on the podium, when he encountered the difficulty that all younger conductors must face when they try to get orchestras and opera houses to do things their way rather than they way they're used to.
In our attempt to obtain further in vivo evidence of caspase-4 down-regulation mediated by an FE65/Teashirt complex, we encountered the difficulty that the CASP4 gene was not represented in the mouse genome (discussed further below), preventing us from utilizing mouse models of AD as well as knockout mice.
The comparison of entirely different matrices such as gels, nanofibers and sponges has to encounter the difficulty that the physical properties of the matrices like stiffness/elasticity, stability, diffusion of nutrients, pore size and many others differ in a wide range.
Many are blessed with never having to encounter the difficulties that life can bring.
I can see the difficulties that might be encountered in bringing about these ideas.
For now, however, the mansion in Wichita that Ms. Alley helped refurbish stands as an outsider in the religious community, a testament to the difficulty that Scientology encounters, despite its celebrity friends.
This increases the difficulty that biologists encounter when analyzing these dataset and constructing a statistical model.
