When suggesting a restriction, information about possible substitutes is essential: Some substitutes are already known but not much is known about their properties and their long-term effects.
In most recipes, using a particular cheese is usually not essential, and substitutes are given.
This suggested that these non-essential genes might substitute for one another in performing essential functions.
Family relations often attend obstetrics and gynecology departments, and it is essential not to substitute an explanation to a family member for an explanation to the patient, who must herself consent.
Some divalent metal ions such as Cd2+ tend to substitute physiologically essential metal ions that act as enzyme cofactors or as structural constituents of proteins.
The ceasing of Global Fund support in China in 2013 will pose a threat to the development of integrated model because the local government in poorer provinces may not substitute the essential financial support.
However, other metals, such as lead (Pb), mercury (Hg), and cadmium (Cd) may displace or substitute for essential trace metals and interfere with proper functioning of enzymes and associated cofactors.
As a substitute to essential oils, try some Lush bath bombs.
If you don't have essential oils, you can substitute 4-5 tablespofns of the dried herb of the respective oil.
The control of the in vivo vascularization of engineered tissue substitutes is essential in order to obtain either a rapid induction or a complete inhibition of the process (e.g. in muscles and hyaline-cartilage, respectively).
In surgical disciplines, where bones have to be repaired, augmented or improved, bone substitutes are essential.
