The phrase "after extensive work" is correct and usable in written English.
You can use it to indicate that a significant amount of effort or time has been spent on a task or project before a certain point or outcome.
Example: "After extensive work on the project, we finally achieved the results we were aiming for."
Alternatives: "following thorough effort" or "after considerable effort".
His career at Skadden came in mid-life after extensive work in the non-profit sector.
After extensive work, the company designed a small box that would allow you to stream movies to your TV.
The high risk was calculated even after extensive work to make the area as unattractive as possible to birds, such as cutting down woodland, draining ponds, planting artificial grass and shooting birds when necessary.
After extensive work on fossils from localities such as Sirius Passet in Greenland, his name has more recently become synonymous with the study of fossil pigments: in ink sacs from ancient squid, and perhaps more famously in the feathers of avian dinosaurs and fossil birds from Brazil, Germany and China.
After extensive work in the 1960s and 1970s, McClintock and her collaborators published the seminal study The Chromosomal Constitution of Races of Maize, leaving their mark on paleobotany, ethnobotany, and evolutionary biology.
Despite an easy clinical diagnosis, precise identification of colovesical fistulas is often challenging and is obtained in only 55% of patients after extensive work-ups.
Our patient initially presented with multiple systemic disseminating infections and, after extensive work-up, was diagnosed with HIV infection with low CD4 count of 4 cells/μl.
Percutaneous biopsy may still be required in some of the patients for definitive diagnosis, even after extensive work-up with imaging studies.
After follow-up period of 5 years these patients were further divided into two groups: (a) patients that converted to relapsing remitting MS (RRMS) (Clinically Isolated Syndromes, CIS group); (b) patients that did not convert to MS and after extensive work-up a better explanation for the clinical and imaging findings was established (NonMS group).
Worcester conducted extensive work after the report at a cost of £3,431 £364,0000 at 2009 prices), and by 1788 the prison had 18 new cells for men and two for women, in addition to the dungeon and the sick-rooms.
But this patient's neutropenia was described as idiopathic; after an extensive work-up, they still hadn't found the cause.
