[1] Mackay Med Coll, Inst Long Term Care, New Taipei 252, Taiwan
[2] Mackay Mem Hosp, Dept Med Res, Taipei 104, Taiwan
[3] Natl Yang Ming Univ, Inst Clin Sci, Taipei 112, Taiwan
[4] Natl Yang Ming Chiao Tung Univ, Inst Clin Sci, Taipei 112, Taiwan
[5] Huang Kuang Univ, Dept Nursing, Taichung 433, Taiwan
[6] Natl Def Med Ctr, Dept Microbiol & Immunol, Taipei 114, Taiwan