We speculate that repeated application may be necessary for treating difficult wounds with the lyophilized product, because the lyophilized cells release the mediators in a single, transient burst.
Estimates of genetic correlations may be necessary for accurate predictions (Grant and Grant 1995) but are difficult to estimate mainly because of the large number of families required to obtain a reasonably small standard error (Roff 1997; Lynch and Walsh 1998).
Difficult times are necessary for a good performance — the big spill of emotion, from tragedy to enormous joy".
The lesson I draw is that while "decentralisation is necessary for effective governance", it is risky, difficult and needs constant thought, strong structures and tools, and regular evaluation.
In contrast, siderophores are necessary for Fe uptake, which becomes increasingly difficult at higher pH.
In certain cases, your doctor may believe that a course of abstinence is necessary for you to heal from a difficult birth, an abdominal wound or surgery, or a trauma.
Certainly innovations like Wikipedia would become very difficult if it were necessary for us to police everything that users were doing against some blacklist of websites.
All participants expressed great satisfaction with IOI using the BIG, particularly in cases with difficult IVI. IVI is necessary for fluid infusion and medication administration in acutely affected patients as an emergency treatment in prehospital settings [15].
Overall, building trust with clients was said to take time, but it was necessary for strengthening clients, especially with clients with difficult life experiences and often a feeling of constant failure.
Promotion and relegation between the two "leagues", which is necessary for a really dynamic university sector, will become more difficult.
