Sentence examples for substances are difficult from inspiring English sources

They wanted an implant that wouldn't degrade over time, but permanent substances are difficult to control once they're in the body.

The primary limitation is the sensitivity: Many substances are difficult to detect at clinical field strengths (3 T and below), both due to limited concentration and spectral overlap of signals from different nuclei, potentially in different molecules (the frequency difference between signals from protons with different chemical shift increases with the strength of the magnetic field).

Recovery from any substance is difficult but staying substance-free is the really hard bit.

In rat motor thalamus, distinguishing the border between VA and VL on the basis of cytoarchitecture (i.e. labeling of Nissl substance) is difficult (Fig.  1 A).

Prosecutors have depicted Ms. de Berk as a dangerous, cunning woman -- either increasing dosages of medicines already being administered, or giving her victims large doses of substances that are difficult to detect.

The effect of these factors in envenoming probably renders the bite site more susceptible to other components of the venom and distribute the substances that are difficult to infiltrate the target tissue [ 39].

However, particular abstract concepts (e.g. keep frozen and cancer-causing substance), which are difficult to represent symbolically, may need to rely on verbal cues, which is the only cue type that did not receive strong support from the results of this study.

Like hypergolic fuel, the oxidizers are extremely toxic substances and so are difficult to handle.

Because the effect concentrations of human or synthetic hormones are often below the limits of quantitation (LOQs) of analytical methods, these substances are analytically difficult to monitor but their effects can be measured with specifically designed assays [12].

Unfortunately, it is common for patients in substance abuse treatment that they are difficult to contact after dropout, probably because they often suffer from various psychosocial problems as well.

Poorly water-soluble drug substances that exhibit high melting points are difficult to process by melt extrusion due to chemical instability at high temperatures required for processing.