Mutation analysis of very-long-chain acyl-coenzyme A dehydrogenase(VLCAD)deficiency: identification and characterization of mutant VLCAD cDNAs from four patients(極長鎖脂肪酸アシルCoAデヒドロゲナーゼ(VLCAD)欠損症の遺伝子変異解析: 4例の患者におけるVLCAD cDNA変異の同定とその特徴)