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)
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)
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)
We studied the relation between the fetal cerebral circulation and changes in the cerebral circulation directly after birth. With a combined real time ultrasound/pulsed Doppler technique flow velocity waveforms from the fetal umbilical- and carotid-circulation were monitored. Pulsatility Index (PI) was computed and the ratio between Umbilical PI and Carotid(More)
OBJECTIVE To compare safety and cost-effectiveness of domiciliary antenatal fetal monitoring (cardiotocography and obstetric surveillance) with in-hospital monitoring in high-risk pregnancies. METHODS From September 1992 to June 1994, 150 consecutive women with high-risk pregnancies, who would otherwise be monitored in the hospital, entered a randomized(More)
In the pathogenesis of neonatal intracranial pathology and adverse neurologic outcome, severe instability of the neonatal cerebral circulation might play an important role. To examine this hypothesis the relationship was explored between intracranial pathology as detected by neurosonography during the first week of life, changes in cerebral blood flow(More)
OBJECTIVE To assess maternal health outcome, comparing high-risk pregnant women to either domiciliary monitoring or in-hospital monitoring, and a low risk pregnant group. DESIGN Paper and pencil questionnaire, distributed antenatal and 8 weeks after the delivery. SETTING A university hospital. SUBJECTS Three groups: 130 high-risk pregnant women, who(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)
PURPOSE We determined the outcome of pregnancy and long-term renal function in cases of sonographically detected fetal urinary tract anomalies (UTAs). METHODS This was a retrospective cohort study done at an academic hospital (tertiary referral center). All records of prenatal sonographic examinations done between January 1985 and October 1994 that(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)