ABSTRACT
Objective To explore the best time period of pulse oximetry in congenital heart disease (CHD) screening. Methods Totally 5433 newborns delivered or treated in Ningbo Women and Children’s hospital were enrolled in the study. Cardiac color ultrasound was used to arrive diagnosis and every screening time period (0?~?24 h、24 h?~?48 h、48 h?~?72 h) was analysed. Results Among the three time periods: the sensibility was in the range of 54.72%?~?67.92%, specificity was 99.11%?~?99.61%, false negative rate was 32.08%?~?43.40%, false positive rate was 0.39%?~?0.89%, Youden index was 0.54?~?0.68, coincidence rate was 98.67?~?99.30, and kappa was 0.44?~?0.65. Conclusion The best screening time is the period between 48h and 72 h after birth.
ABSTRACT
Objective:To compare the differences of bond strength usi ng gold intermediate layer between Ni-Cr alloy and opaque porcelain(OP) baked at different temperatures. Methods:36 standard samples of Ni-Cr al loy and 36 of gold were prepared. The samples were divided into 4 groups with 9 in each. In group 1,OP was smeared to the surface of the samples and then baked at 950 ℃. In group 2,3 and 4 blendgold neu(a gold past) was put on the surface of the samples, then baked at 820 ℃,890 ℃ and 960 ℃ respectively. The samples were proccessed for further tests.The bond strength was tested by shear bond te st, and the electron probe was used to observe interfacial bond state and diffus ion of interfacial elements. Results:The bond strength(MPa) in g roup 1,2,3 and 4 was 19.66? 1.83,22.34?2.73,21.33?2.75 and 28.02?5.71 res pectively(group 1 vs group 4 P