Hans A Zondervan

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BACKGROUND The Rh system is complex and consists of as many as 45 different antigens. Red cells of about 25 percent of the black population carry VS an Rh-system antigen (Rh20), but this antigen is very rare in whites. VS positivity is always associated with a weak expression of e, and usually also of C. STUDY DESIGN AND METHODS The RH genes of 11 black(More)
BACKGROUND VS and V are common red cell antigens in persons of African origin. The molecular background of these Rh system antigens is poorly understood. STUDY DESIGN AND METHODS Red cells from 100 black South Africans and 43 black persons from Amsterdam, the Netherlands, were typed serologically for various Rh system antigens. Allele-specific polymerase(More)
OBJECTIVE To determine whether baseline characteristics during early pregnancy, proposed as potential risk factors for preeclampsia, show differences in prevalence and effects within distinct ethnic groups. METHODS In a prospective cohort study of 2413 healthy nulliparous women from eight midwives' practices, we analyzed risk factors for preeclampsia(More)
Intrauterine growth restriction (IUGR), occurring preterm, may be related to impaired neurodevelopmental outcome. We measured neurodevelopmental outcome (Hempel examination) at the age of three years in a cohort of infants born between 26 and 33 weeks in 1989. Fetuses were studied haemodynamically, using Doppler ultrasound. The ratio between the umbilical(More)
OBJECTIVE Our purpose was to assess the effects that fetal growth restriction exerts on the myelination of the developing brain. STUDY DESIGN Fetal haemodynamic centralization, an adaptive strategy to growth restriction caused by placental insufficiency, was determined by Doppler ultrasonography. Infants with a raised ratio between umbilical artery(More)
OBJECTIVES This study was designed to compare the effects of transcervical chorionic villus sampling (CVS) and amniocentesis on the prevalence of hemangiomas of infancy. METHODS This is a cohort study of 250 consecutive assessable transabdominal amniocentesis procedures and 250 consecutive assessable transcervical CVS procedures performed between January(More)
To explore the relevance of the rheological properties of maternal blood in pregnancy to fetal growth a study of whole blood viscosity (WBV) was conducted in the early third trimester of 138 pregnancies. A significant negative correlation was found between WBV at low shear rate and birthweight centile. As the rheological parameters were found to be(More)
A survey among workers in a steel factory was conducted to determine the risk for low-back pain (LBP) among male crane operators. Crane operators (n = 33) were matched for age with male control workers (n = 30) and examined for frequency and nature of LBP by the on-site medical service. Comparison between crane operators and controls showed a statistically(More)
The effect of antenatal brainsparing on subsequent neonatal cerebral blood flow velocity (CBFV) was studied in very preterm infants. CBFV was determined, using a pulsed Doppler technique, both in the fetal and neonatal period. Neonatally, blood pressure and transcutaneous carbon dioxide tension (TcPCO2) was monitored simultaneously; daily cranial ultrasound(More)