The phrase 'fruitful effect' is correct and usable in written English.
It is usually used to describe a positive outcome or result of an action. For example, "The changes made to the team's work ethic had a fruitful effect on their productivity."
The former has been a fruitful field of research; many side effects of drugs have been discovered by these observational studies.
A FRUITFUL result for you!
Further, fruitful investigations could target the specific genetic loci that underlie the parent-of-origin dependency of alcohol effects.
This research will be carried out on the (currently being built) OMEGA EP petawatt and OMEGA lasers at the University of Rochester in New York and at the GEKKO XII laser at the Institute for Laser Engineering in Osaka, Japan, which, if fruitful, may have the effect of greatly reducing the cost of a laser fusion-based power source.
While it's still too early to apply the research to the human brain, the effects could prove fruitful for people struggling with mental illness, since disorders like depression and PTSD are often linked with damaged neurites in the prefrontal cortex.
On the basis of these results and similar outcomes in larger studies (J.M. Hagberg, personal communication), it would be fruitful to study the effects of exercise and/or metformin in the different subgroups of prediabetes to better understand the effects of fasting hyperglycemia.
The fMRI results brought us fruitful information to scrutinize effects of reward motivation over action inhibition and relevant processes.
For this reason, the study of unconscious states, such as sleep, may prove to be especially fruitful in understanding the effects of attention in the waking state.
This illustrates that multilevel models and analyses of interactions effects are fruitful tasks.
