Highlighting text in a PDF document is handy for marking important areas you can access later. You can use Microsoft Edge to highlight PDF or any other software with a PDF highlighting feature.

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Despite accumulating evidence in support of sex-based differences in innate and adaptive immune responses, in the susceptibility to infectious diseases and in the prevalence of autoimmune diseases, ...

For a definitive list of which limits are mandatory please visit the submission checklist page. We allow the use of up to 6 keywords/key phrases that can be used for indexing purposes. These should ...