Use {{Endocrine system procedures |state=collapsed}} to show this template in its collapsed (hidden) state.
Use {{Endocrine system procedures |state=expanded}} to show this template in its expanded (fully visible) state.
Use {{Endocrine system procedures |state=autocollapse}} to show this template in its collapsed (hidden) state only if there is another template of the same type on the page.
Unless set otherwise (see state parameter within the template's code), autocollapse is the default state.