0000000000125768

AUTHOR

S. Wellek

showing 8 related works from this author

Prospective randomised trial of chemotherapy given before radiotherapy in childhood medulloblastoma. International society of paediatric oncology (SI…

1995

In a multicentre randomised clinical trial 364 children with biopsy proven medulloblastoma were randomly assigned to receive or not pre-radiotherapy chemotherapy. Children with total or subtotal removal of the tumour, no evidence of invasive brain stem involvement, and no evidence of metastatic disease either within or without the cranium were designated "low risk", those with gross residual tumour, evidence of invasive brain stem involvement or metastases in the central nervous system were designated "high risk". All children were prescribed 55 Gy to the tumour bearing area. "Low risk" children could be randomised to "standard" radiotherapy 35 Gy to the craniospinal axis or "reduced" dose …

MaleCancer ResearchVincristinemedicine.medical_specialtyPediatricsTime FactorsAdolescentmedicine.medical_treatmentProcarbazinelaw.inventionRandomized controlled trialRecurrenceRisk FactorslawAntineoplastic Combined Chemotherapy ProtocolsHumansMedicineProspective StudiesCerebellar NeoplasmsChildProspective cohort studyMedulloblastomabusiness.industryInfantRadiotherapy Dosagemedicine.diseaseCombined Modality TherapySurvival AnalysisSurgeryRadiation therapyClinical trialOncologyChild PreschoolPediatrics Perinatology and Child HealthFemalebusinessCraniospinalMedulloblastomamedicine.drugMedical and Pediatric Oncology
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Prenatal Risk Calculation (PRC) 3.0: An Extended DoE-Based First-Trimester Screening Algorithm Allowing For Early Blood Sampling

2015

Aim: Both previous versions of the German PRC algorithm developed by our group for routine first-trimester screening relied on the assumption that maternal blood sampling and fetal ultrasonography are performed at the same visit of a pregnant women. In this paper we present an extension of our method allowing also for constellations where this synchronization is abandoned through preponing blood sampling to dates before 11 weeks of gestation. Methods: In contrast to the directly measured concentrations of the serum parameters PAPP-A and free ß-hCG, the logarithmically transformed values could be shown to admit the construction of reference bands covering the whole range from 16 to 84 mm CRL…

lcsh:Medical physics. Medical radiology. Nuclear medicinemedicine.medical_specialtylcsh:R895-920lcsh:MedicinePrenatal diagnosisScreening algorithm030218 nuclear medicine & medical imaging03 medical and health sciences0302 clinical medicineStatisticsMedicineCutoffRadiology Nuclear Medicine and imagingprenatal diagnosisfirst trimester screening030219 obstetrics & reproductive medicinebusiness.industrylcsh:RSampling (statistics)risk calculationmedicine.diseaseSurgeryGestationFalse positive ratebusinessTrisomyBlood samplingUltrasound International Open
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OP07.07: First trimester screening: comparison of different risk calculation programs in 115,864 patients

2012

First trimestermedicine.medical_specialtyReproductive MedicineRadiological and Ultrasound Technologybusiness.industryObstetricsObstetrics and GynecologyMedicineRadiology Nuclear Medicine and imagingGeneral MedicineRisk assessmentbusinessUltrasound in Obstetrics & Gynecology
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Reference values of fetal aortic flow velocity waveforms and associated intra-observer reliability in normal pregnancies

2001

Objectives It was the aim of the present study to calculate new Doppler reference ranges for blood flow velocities (Vmax, Vmean, Vmin) and resistance indices (PI, RI) for the fetal descending aorta by automatic waveform analysis. Design Cross-sectional prospective study. Subjects Nine hundred and twenty-six low-risk pregnancies at 18–41 weeks' gestation. Methods Aortic blood flow velocities were derived with pulsed-wave color Doppler. Measurements were carried out at the level of the diaphragm. Reference ranges for the individual measuring parameters were constructed based on a growth function from a four-parameter class of monotonic continuous functions according to the smallest square pri…

Aortic archmedicine.medical_specialtyDuplex ultrasonographyAortaRadiological and Ultrasound Technologybusiness.industryObstetrics and GynecologyHemodynamicsGeneral MedicineBlood flowSurgerysymbols.namesakemedicine.anatomical_structureReproductive MedicineInternal medicinemedicine.arteryDescending aortaVascular resistancemedicinesymbolsCardiologyRadiology Nuclear Medicine and imagingbusinessDoppler effectUltrasound in Obstetrics and Gynecology
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Biometry of the fetal corpus callosum by three-dimensional ultrasound

2013

Objectives To construct reference ranges of quantitative characteristics of the fetal corpus callosum. Methods Women referred to a tertiary center for sonographic examination were recruited to undergo a detailed fetal scan from 17 to 41 weeks of gestation. Three-dimensional (3D) sonographic volumes of normal fetal brains were acquired and analyzed offline. We obtained three different measurements of the corpus callosal length, as well as the height (/thickness) of its segments, namely the rostrum, genu, body and splenium. Results Initially we recruited 604 pregnant women, of whom 138 were excluded because of various disorders/abnormalities, multiple pregnancy or gestational age < 18 weeks. …

FetusRadiological and Ultrasound Technologymedicine.diagnostic_testbusiness.industryUltrasoundRostrumObstetrics and GynecologySpleniumGestational ageGeneral MedicineAnatomyCorpus callosumDysgenesisReproductive MedicineMedicineRadiology Nuclear Medicine and imaging3D ultrasoundbusinessUltrasound in Obstetrics &amp; Gynecology
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Age-Related Reference Ranges for Fetal Foot Length

2000

AIM The aim of this study was to establish age-dependent reference ranges for fetal foot length with gestation as well as for the femur/foot length ratio, based on a mathematical growth model. METHOD In a prospective cross-sectional study of 610 pregnancies with sonographically confirmed gestational age (< 12 weeks' gestation), fetal biometry was performed in addition to measurements of fetal foot length between 12 and 42 completed weeks of gestation. Reference ranges for the fetal foot and for the femur/foot length ratio were constructed with an overall coverage of 90% of the measured data, using a previously established method of determining reference bands for growth parameters. RESULTS …

FetusFootbusiness.industryGestational ageGestational AgeReference rangeGrowth modelAnatomyUltrasonography PrenatalEmbryonic and Fetal DevelopmentCross-Sectional StudiesFetusPregnancyReference ValuesAge relatedHumansGestationMedicineFemaleRadiology Nuclear Medicine and imagingFemurFemurNuclear medicinebusinessFoot (unit)Ultraschall in der Medizin
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Vergleich der DNS-Analyse mit histomorphologischen parametern beim Magenkarzinom

1992

After curative resection of stomach carcinomas (adenocarcinomas: n=58, signet ring cell carcinomas: n = 24, undifferentiated carcinomas: n = 21) the DNA content of the tumor cells was compared with the histomorphological parameters. There was a correlation between the DNA content and the histomorphological parameters. The DNA analysis had no additionally prognostic influence. In the multivariate regression analysis the prognosis depended on lymph node status (p=0.0009), pT-stage (p = 0.02), tumor localization (p = 0.03) and the histological type (p=0.05). The prognosis was independent of the DNA content. Furthermore, neither did the degree of differentiation, the operative procedure, the sa…

Curative resectionPathologymedicine.medical_specialtyHistological typeSignet ring cellbusiness.industryStomachTumor cellsmedicine.anatomical_structureSTOMACH CARCINOMAmedicineSurgeryUndifferentiated carcinomabusinessLymph nodeLangenbecks Archiv fur Chirurgie
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Parametrische Tests für den Vergleich von Mittelwertsprofilen bei Unverbundenen Beobachtungen mit Homogenen Varianzen

1981

Sowohl in experimentellen als auch in klinischen Zusammenhangen sind nicht selten Parameter von Interesse, deren wiederholte Messung an derselben Beobachtungseinheit aus technischen Grunden unmoglich ist.

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