# Number in newtheoremstyle is not italic

I defined and used a new theormestyle using amsmath package:

\newtheoremstyle{standard}
{\topsep}      % ABOVESPACE
{\topsep}      % BELOWSPACE
{\normalfont}  % BODYFONT % \itshape
{0pt}          % INDENT (empty value is the same as 0pt)
{0pt}          % HEADSPACE. plain default: {5pt plus 1pt minus 1pt}


When I see it correctly this leads e.g. to Remark 1. instead of Remark 1.
So the number is not italized. How should I do that?
Maybe internally the \emph environment is applied to the number, neutralizing italics already in place.

Use

{\thmname{#1} \thmnumber{#2}}             % CUSTOM-HEAD-SPEC


MWE:

\documentclass{article}
\usepackage{mathtools,amsthm,amsfonts}
\newtheoremstyle{standard}
{\topsep}      % ABOVESPACE
{\topsep}      % BELOWSPACE
{\normalfont}  % BODYFONT % \itshape
{0pt}          % INDENT (empty value is the same as 0pt)
{0pt}          % HEADSPACE. plain default: {5pt plus 1pt minus 1pt}
Let $I \subset \mathbb{R}$ be an interval.