Coronary echocardiography in tetralogy of fallot: diagnostic accuracy, resource utilization and surgical implications over 13 years.

Objectives: This study sought to determine the diagnostic accuracy and impact of the systematic use of coronary echocardiography in a large group of preoperative patients with tetralogy of Fallot (TOF).

Background: Accurate preoperative identification of an anomalous coronary artery crossing the right ventricular outflow tract (RVOT) in patients with TOF is important to prevent coronary injury during surgical repair.

Methods: A retrospective review identified 598 patients with TOF between 1983 to 1995 who underwent an echocardiogram at <2 years old before complete surgical repair.

Isolation and characterization of the rat thyrotropin beta-subunit gene. Differential regulation of two transcriptional start sites by thyroid hormone.

The gene encoding the beta-subunit of rat thyrotropin (TSH beta) has been isolated and characterized. Blot hybridization of restriction enzyme digests of rat genomic DNA suggests that the gene is present in a single copy. The transcriptional unit is 4.

Regulation of rat luteinizing hormone subunit messenger ribonucleic acids by gonadal steroid hormones.

Little is known about the hormonal regulation of luteinizing hormone (LH) biosynthesis. We have studied the regulation of LH messenger RNA (mRNA) levels by gonadal-steroid hormones in the rat. In one set of experiments, male and female rats were surgically gonadectomized (GDX) and killed 1, 3, 7, 14, 22, and 31 d postoperatively.