The phrase "has long accumulated" is correct and commonly used in written English.
It can be used to describe something that has been building up or growing over a long period of time. Example: The city's pollution problem has long accumulated due to the increase in industrial activity over the past few decades.
The treatment is based on a deep insight into the nature of cancer cells and will, if it works, become one of the first practical contributions to cancer therapy of the theoretical knowledge that has long been accumulating.
"I've tended to take the attitude, 'Don't throw electronic things away.' " Although he has long been accumulating this data, he never got around to analyzing it until a few months ago.
(2) The U.S. has incurred trade deficits repeatedly for far longer than can be explained by its having the world reserve currency, and the Chinese Central Bank has long been accumulating reserves, thanks to its trade surpluses.
It has long been thought that abnormal tau accumulates in a cell-autonomous manner and that its distribution reflects the greater vulnerability of some neuronal populations, possibly related to variations in tau expression.
Fluoroquinolones have long been known to accumulate in eukaryotic cells.
Many of these workers have long been employed and have accumulated savings and assets such as houses, which makes them ineligible for support, he said.
An ideal siRNA delivery vehicle for systemic administration should have long circulation time in blood, accumulate at tumor site, and sufficiently internalize into cancer cells for high-efficiency of gene silence.
Since only stem cells have long enough life spans to accumulate mtDNA mutations to detectable levels of homoplasmy, a clonal population marked by a particular mtDNA mutation likely represents the progeny of a single mutated stem cell (Elson et al., 2001; Greaves et al., 2006; Fellous et al., 2009).
Kentucky's commissioner of education, Terry Holliday, said high school graduation requirements there had long been based on having students accumulate enough course credits to graduate.
Pharmacokinetic studies with both radiolabeled dexamethasone and polymer showed that these polymeric systems have long circulating half-lives and may accumulate at the tumor site to a higher extent than liposomes.
For example, reporter gene assays have been used to measure c-Myb activity, but rely on the production of reporter enzymes, which must accumulate and could have long half-lives.
