PubMed Health⌕ Search

Biomedical subjects

H Neff

Publications and source records attributed to H Neff.

9 recordsLinked to original sources
PubMed2005

dc-Sheet resistance as sensitive monitoring tool of protein immobilization on thin metal films.

The suitability of high resolution, in situ dc-sheet resistance monitoring (SRM) as a simplified and reliable sensing technique towards detection and tracking of protein immobilization has been explored. Non-specific adsorption of bovine serum albumin (BSA) onto a very thin gold film, acting as the sensing resistor, has been employed as a model system. For comparison, the novel sensing method was combined with surface plasmon resonance (SPR) spectroscopy, using the same flow cell and sensing surface. Two different, well known adsorption states, involving a composite layer of irreversibly and reversibly bound BSA, were clearly resolved by both methods. Clearly structured, pronounced and fully reproducible film resistance modulations have been resolved in the associated SRM data. The transition from reversibly bound BSA to the diluted protein phase is associated with an unusually large decrease in the dc-sheet resistance. The observed resistance modulation magnitude for an adsorbed BSA monolayer corresponds to approximately 1%, and up to 100 mOmega at a 10 Omega sensing resistor. The sheet resistance of irreversibly bound BSA was determined to 0.24 kOmega/cm2, and the associated specific resistivity estimated to 1-2x10(4) Omega cm.

Adsorption↗
PubMed2005

N-to-delta electromagnetic-transition form factors from lattice QCD.

The magnetic dipole (M1), the electric quadrupole (E2), and the Coulomb quadrupole (C2) amplitudes for gammaN-->Delta are calculated in quenched lattice QCD. Using a new method, which combines an optimal choice of interpolating fields for the Delta and an overconstrained analysis, we obtain statistically accurate results for the dipole form factor and for the ratios R(EM)=E2/M1 and R(SM)=C2/M1, up to momentum transfer squared 1.5 GeV2. We show for the first time, using lattice QCD, that both R(EM) and R(SM) are nonzero and negative, in qualitative agreement with experiment and indicating the presence of deformation in the N/Delta system.

Journal Article↗
PubMed1999

[Adhesion molecule ICAM-1 in patients with chronic polyarthritis--effects of inpatient rehabilitation].

In rheumatoid arthritis (RA) the adhesion molecule ICAM-1 mediates the adhesion of leucocytes following subsequent transendothelial migration including interactions and adhesion of several cell types such as fibroblasts, T-lymphocytes and synoviocytes. Significantly increased ICAM-1 levels were measured in the acute phase of RA. The correlation of ICAM-1 levels with the pteridine neopterin (p < or = 0.01) may reflect the role of this adhesion molecule in modulation of immune responses. Despite the significantly higher levels of acute phase reactions parallel to the elevated ICAM-1 levels, no correlations were found between ICAM-1 and erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and serum-Amyloid A (SAA). During an in-patient multidisciplinary rehabilitation programme the levels of ICAM-1 in serum and the majority of all investigated laboratory and clinical parameters such as ESR, CRP, SAA, fibrinogen, pain, swollen and painful joint count, morning stiffness and health assessment questionnaire improved.

Acute-Phase Proteins↗
PubMed1976

[Hazards in the operative treatment of Ductus Botallo (author's transl)].

Possible errors and risks in operations of the ductus Botallo are discussed by using the experience from 282 operations. In young patients and adults the operative closure has to be decided upon according to the degree of the pulmonary vascular resistance. In newborns the closure of the ductus should be performed when symptoms such as heart insufficiency, frequent pneumonias and cyanosis are present. Haemorrhage due to damage of the walls is most frequent intraoperative complication. The procedure of controlling is dealt with more in detail. At least possibilities to treat the so called recanalisation or pseudorecidive are discussed. No patient was lost by intraoperative complications. The total mortality amounted to 1.4 per cent.

Adult↗