High risk factors analysis of stillbirth / 中华妇产科杂志

Objective To explore the high risk factors of stillbirth. Methods 176 cases of stillbirth were collected in the Obstetrics and Gynecology Hospital of Fudan University from January 1st, 2010 to December 31st, 2016. All cases were analyzed retrospectively, including general profile, high risk factors of stillbirth in different years and pregnancy periods. Results (1) The incidence of stillbirth was 0.178%(176/98 785). Stillbirth occured mostly at 28-28+6gestational weeks (10.8%,19/176), and the second peak was 29-29+6weeks(10.2%,18/176),while the third common period was 37-37+6weeks(9.1%,16/176).After 39 weeks,it maintained at a low level.(2)The top 5 high risk factors of stillbirth were infection (18.2%,32/176), unexplained (13.6%,24/176), hypertention disorders in pregnancy (13.1%, 23/176), umbilical cord torsion(12.5%,22/176)and fetal malformations(10.2%,18/176).(3)From 2010 to 2012,the top 3 high risk factors were unexplained, the umbilical cord torsion and infection, while hypertention in pregnancy,infection and fetal malformation became the top 3 high risk factors after 2013.(4)Early stillbirth (20-27+6weeks)accounted for 21.6%(38/176);and unexplained(47.4%,18/38),fetal edema(13.2%,5/38), infection(13.2%,5/38),umbilical cord torsion(5.3%,2/38)were the top 4 high risk factors.Late stillbirth(≥28 weeks)accounted for 78.4%(138/176),with infection(19.6%,27/138),hypertention in pregnancy(15.9%, 22/138), umbilical cord torsion (14.5%,20/138) and fetal malformation(12.3%,17/138)being the top 4 high risk factors. Conclusions More attention should be paid to maternal complications, especially infection and hypertension in pregnancy. Antenatal fetal monitoring, timely termination of pregnancy, standard management of stillbirth and looking for the causes may help reduce the incidence of stillbirth.

Method for determining o-tolidine in workplace air by gas chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish a method for determining o-tolidine in workplace air by gas chromatography.</p><p><b>METHODS</b>o-tolidine in workplace air was collected with a glass fiber filter, desorbed with methanol, and determined by gas chromatography-flame ionization detector.</p><p><b>RESULTS</b>The concentration of o-tolidine showed a linear relationship with peak area within 0.04∼9.00 µg/ml; the detection limit was 0.04 µg/ml; the minimum detectable concentration was 0.0002 mg/m(3) (calculated by 375 L air sample); the sampling efficiency was 93%∼100%; the elution efficiency was 94%∼96%; the relative standard deviation was 0.8-2.5%. Sample could be stored at 4 °C for at least 8 days and at room temperature for as long as 6 days.</p><p><b>CONCLUSION</b>This determination method meets the requirements of Guide for establishing occupational heath standards-Part 4 Determination methods of air chemicals in workplace (GBZ/T 210.4-2008) and is suitable for determination of o-tolidine in workplace air.</p>

Ion chromatography for determination of ammonia sampled by silica gel in air of workplace / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish an ion chromatography (IC) method for determination of ammonia in air of workplace.</p><p><b>METHODS</b>Ammonia in workplace air was collected in silica gel tube, desorbed with 10 mmol/L methanesulfonic acid by ultrasonic for 10 min, determined by IC.</p><p><b>RESULTS</b>The linearity range was 0.02-1.00 microg/ml. The linear equation was Y = 12041X-187 (r = 0.9997). The limit of quantification was 0.13 mg/m3 (the air volume was 1.5 L). Collection efficiency was 100%. Extraction efficiency was 99%. The relative standard deviation was 4.2%-6.3%. The penetration capacity was more than 264 microg. Sample could be stored for 14 days at least by ambient storage.</p><p><b>CONCLUSION</b>This method is convenient, applicable and sensitive, suitable to determinate ammonia in air of workplace.</p>