private void button1_Click(object sender, EventArgs e)
{
ThemThongTinBenhNhan bn = new ThemThongTinBenhNhan();
bn.ShowDialog();
this.Hide();
}
private void thêmBệnhNhânToolStripMenuItem1_Click(object sender, EventArgs e)
{
ThemThongTinBenhNhan x = new ThemThongTinBenhNhan();
x.ShowDialog();
}