0000000000235314
AUTHOR
W. Baumann
showing 18 related works from this author
Voltammetric behavior and assay of the contraceptive drug levonorgestrel in bulk, tablets, and human serum at a mercury electrode.
2004
The cyclic voltammograms of levonorgestrel (LNG) in Britton-Robinson buffers of pH 2-11 at the hanging mercury drop electrode showed a single two-electron irreversible cathodic peak over the whole pH range. This peak may be attributed to the reduction of the 3-keto-delta-4-group in the A-ring of the LNG molecule. The interfacial adsorptive character of levonorgestrel onto the surface of the hanging mercury drop electrode was identified by means of both cyclic voltammetry and chronocoulometry techniques. A simple, sensitive, and selective square-wave adsorptive cathodic stripping voltammetric procedure was developed for the quantitation of levonorgestrel. Under the optimized operational cond…
Real-time ultrasound in Crohn's disease: characteristic features and clinical implications.
1986
Thirty-two children with Crohn's disease were evaluated by real-time ultrasonography. The typical pattern of Crohn's disease caused by bowel wall thickening is the “bull's eye phenomenon”, the elongated tubular stiff bowel loop with narrowing of the lumen and the small bowel conglomerate tumor. In indefinable abdominal complaints sonography may lead to the correct diagnosis. The differential diagnosis of similar sonographic features and the limitations of ultrasound in gastrointestinal disease must be considered. In proven Crohn's disease the findings in follow-up match the clinical course and may delineate complications, such as ileus, abscess, hydronephrosis, gallstones or involvement of …
Congenital renal arteriovenous malformation (aneurysmal type) in childhood.
1985
We report on a 9-year-old boy with a congenital renal arteriovenous fistula of the aneurysmal type, a form previously not observed in childhood. The clinical picture was unusual with severe arterial hypertension, excessive polyuria and decreased levels of serum sodium and chloride as main signs. Clinical and biochemical findings normalised after nephrectomy of the kidney involved.
A new shape-oriented classification method for UV/VIS-spectra
1996
A new shape-oriented classification method is described. It is shown, how shapes of UV/VIS-spectra can be classified and coded and how a classification technique can be used to improve database search operations for pre-selections or even shape-oriented identifications.
The diagnostic significance of cholescintigraphy and ultrasound examination in cholestatic syndromes in infancy
1988
Thirty-three neonates and infants with cholestatic syndromes of various etiologies were evaluated by cholescintigraphy and ultrasound examinations. The results of these two diagnostic procedures were compared with the final diagnosis as confirmed by liver biopsy and/or laparotomy and the clinica follow-up of the infants. Fourteen patients had an obstructive cholangiopathy (11 biliary atresia, 2 choledochal cysts, 1 congenital choledochal stenosis), 13 had neonatal hepatitis, and 6 had cholestasis of another etiology. Typical ultrasonic and/or scintigraphic findings confirmed or excluded the need for surgical exploration in 28 patients. Thus, for must infants with cholestatic syndromes it is…
Meßmethoden bei elektrooptischen Untersuchungen
1976
Es werden als Kernprobleme, wie sie bei optischen Untersuchungen an Molekulen in elektrischen Feldern auftreten, die relative und die absolute Mesgenauigkeit getrennt diskutiert. Mit einfachen Uberlegungen werden zur Optimierung der experimentellen Anordnung auf ihre relative Mesgenauigkeit hin Forderungen aus der Photonenstatistik abgeleitet. Die absolute Mesgenauigkeit wird als Problem der Bestimmung der mittleren Feldstarken in einer praktisch verwirklichbaren Meszelle behandelt, und eine geeignete Eichzelle wird beschrieben. The main problem of all optical research on molecules in electric fields is that of relative and absolute accuracy. From simple photon statistics, a procedure for o…
A new fast and fault-tolerant identification algorithm for spectral databases
1995
A new method for an automatic, computer and database driven identification of UV/VIS spectra is described. It is shown that an identification algorithm must consider the spectral differences as well as their common features. The described identification method allows identifications, even if the spectra are distorted or shifted.
Sonographic biometry of liver and spleen size in childhood.
1983
In 194 healthy children of all ages, sonographic measurements of the liver and spleen were performed on standardized section planes and normal values established. These measurement values showed an approximately linear increase in the course of development and correlated best with the body length. For a rapid orientational evaluation of the liver size, sonographic nomograms of the individual measurements were developed. The spleen size was determined by volume calculation. On the basis of an index of liver size, which was calculated from the individual measurements, a diagram for simultaneous determination of liver and spleen size could be developed. These nomograms permit objective morphom…
Molecular Stark-effect spectroscopy of Prodan and Laurdan in different solvents and electric dipole moments in their equilibrated ground and Franck–C…
2007
Abstract The results from electrooptical absorption measurements (EOAM) on the ground and excited Franck–Condon state dipole moments of Prodan and Laurdan in 1,4-dioxane and cyclohexane are presented. The ground and excited Franck–Condon state electric dipole moments as well as the respective transition moment of both probes are parallel. The electric dipole moments of Prodan and Laurdan in the ground state in cyclohexane and 1,4-dioxane have values within the range (15.7–16.5) × 10 −30 C m. On optical excitation the dipole moments increase by (42.1–49.5) × 10 −30 C m. The obtained results are compared with the values of the dipole moments of Prodan and Laurdan determined by other methods.
Cellular cytotoxicity against autologous hepatocytes in children with different forms of chronic hepatitis B.
1990
Cell-mediated immune reactions play the most important role in the pathogenesis of chronic viral and auto-immune hepatitis. Cellular cytotoxicity (CC) of peripheral blood lymphocytes against autologous hepatocytes isolated from liver biopsies was studied in 29 children with different types of hepatitis B surface antigen (HBsAg)-positive hepatitis. Children with chronic hepatitis B showed higher cytotoxicity than control patients. However, a correlation of cytotoxicity to serum amino-transferases, HBeAg-/Anti-HBe-status, and hepatitis B virus DNA in serum could not be found. Children with a higher percentage of hepatitis B core antigen (HBcAg) expression in their liver tissue presented lower…
Chromatographic and spectroscopic properties of regioisomers of some 1H-1,5-benzodiazepines
1994
The separation of the two regioisomeric derivatives of 1H-1,5-benzodia- zepine yielded from the reaction of 1,2-diamino-4-methylbenzene with 4-substituted acetophenones was performed by reversed phase high per- formance liquid chromatography, and the absorption spectra of the sepa- rated isomers have been determined for three isomer pairs which have been obtained starting from acetophenones with substituents of different electronegativity. The isomer ratio then could be estimated as well from the ratio of the peak areas as from the absorption spectra. They agree well with the known ratio determined from nmr intensities
Studies on the kinetics and renal excretion of low and high molecular weight dextrans in preterm babies, newborns and young infants.
1977
Administration of low and high molecular weight dextrans in the initial phase of shock is no longer controversial. The special conditions in newborns, however, have been insufficiently considered in planning therapy. This investigation aimed at determining the biological half-lives of dextran 40 (Rheomacrodex®) and dextran 60 (Macrodex®) in this age group. The half-life of dextran 40 was found to be 60 min and that of dextran 60 3 h. Preterm babies and newborns excrete up to 25% less dextran 40 and 60 in 24 h than infants and adults. Normal adult values for excretion are only reached towards the end of the first year of life.
N-Acetylneuraminic acid storage disease
1985
Increased amounts of free sialic acid were found in body fluids, leukocytes, cultured fibroblasts, and liver tissue of a four-year-old boy with mental retardation, ataxia, and clinical and radiologic findings of a mild mucopolysaccharidosis. A diagnosis of Salla disease was made though in contrast to earlier reports, recurrent upper respiratory infections and hepatosplenomegaly were present already in infancy, and skeletal abnormalities of dysostosis multiplex were found in early childhood. Free sialic acid in the urine was identified as N-acetylneuraminic acid by 1H-NMR spectroscopy. Sialidase activities were normal. Increased amounts of bound sialic acid were found in liver and cultured f…
Zur Morphologie, Klinik und Immunpathologie der Virus B-Hepatitis im Säuglings- und Kindesalter
1980
In Abhangigkeit von der Funktion des Immunsystems reagiert der kindliche Organismus nach einer Hepatitis Virus B-Infektion mit einem breiten Spektrum von verschiedenen HB s Ag-positiven Lebererkrankungen. Wahrend eine normale Immunantwort mit einer Elimination des Hepatitis B-Virus und seiner assoziierten Antigene einhergeht, fuhrt eine inadaquate Immunreaktivitat zu einer Virus- und/oder Antigenpersistenz im Serum und Lebergewebe.
IN SITU HYBRIDIZATION FOR DETECTION OF HEPATITIS B VIRUS GENOMES IN LIVER TISSUE OF CHRONIC INFECTED CHILDREN
1990
Detection of hepatitis B virus (HBV)-DNA in the liver of chronic infected patients is presently the most sensitive marker of viral replication and infectivity. In situ hybridization (ISH) allows the direct visualization of HBV infected liver cells and distribution of the viral sequences. This study was done to establish ISH and correlate the findings with conventional markers for HBV infection. Methods. Liver biopsies of 50 patients (28 ♂, 22 ♀) aged 0.5-20 years (mean 10.3) with various histological diagnoses were tested by 1SH. The HBV-DNA probe was labeled by nick translation with 35S-CTP to a specific activity of 3-5×108 cpm/μg DNA. Results. HBV-DNA/mRNA could be demonstrated in 38 pati…
Klinische Manifestation der Lyme-Borreliose im Kindesalter
1989
We report on 4 children with different clinical manifestations of Lyme-Borreliosis. One patient presented with a stage 2 typical aseptic meningitis and 2 others with symptoms of Schonlein-Henoch purpura and rheumatic disease respectively. A further case had bilateral palsy of abducens nerve and unilateral palsy of trochlearis nerve which are described for the first time in Lyme-Borreliosis. Diagnosis was established by detection of specific antibodies to Borrelia in all patients. Differential diagnosis of these symptoms should include Lyme-Borreliosis.
First experiments with the heidelberg test storage ring TSR
1989
Abstract The Heidelberg heavy ion test storage ring TSR started operation in May 1988. The lifetimes of the ion beams observed in the first experiments can be explained by interactions with the residual gas. Multiple Coulomb scattering, single Coulomb scattering, electron capture and electron stripping are the relevant processes. Electron cooling of ions as heavy as O 8+ has been observed for the first time. With increasing particle number, the longitudinal Schottky noise spectrum becomes dominated by collective waves for cooled beams, allowing a determination of velocities of sound. After correcting for these coherent distortions fo the Schottky spectrum, the longitudinal beam temperature …
Evaluation of the concept of heterology in a monoclonal antibody-based ELISA utilizing direct hapten linkage to polystyrene microtiter plates.
2005
A series of new heterologous haptens has been synthesized and used as coating haptens in an antigen-immobilized immunoassay with a monoclonal antibody against atrazine. Coating was achieved by covalently linking the different haptens to a glutaraldehyde network directly bound to the polystyrene surface of a standard 96-well microtiter plate. With the assay designed in the antigen-immobilized format with direct chemical linkage of the hapten to the solid polystyrene surface well-defined hapten densities were achieved in all experiments. The results of different experiments with different coating haptens were comparable. Using different heterologous haptens it appears that the concept of hete…