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Biomedical subjects

Lj Nikolić

Publications and source records attributed to Lj Nikolić.

At least 19 recordsLinked to original sources
PubMed2002

Stimulated electron-acoustic-wave scattering in a laser plasma.

Intense laser-plasma interaction can be a source of various electronic instabilities. Recently, stimulated backscattering from a trapped electron-acoustic wave (SEAS) [Montgomery et al., Phys. Rev. Lett. 87, 155001 (2001)] was proposed to reinterpret spectra previously attributed to stimulated Raman scattering (SRS) from unrealistically low densities. By particle simulations in a uniform plasma layer, which is overdense for ordinary SRS, strong reflection by SEAS at the electron plasma frequency is found. Transient SEAS reflectivity pulsations are followed by strong relativistic heating of electrons. Physical conditions are explained by three-wave parametric coupling between laser light, standing backscattered wave and slow electron-acoustic wave. Regions in which SEAS reflection can dominate over SRS are singled out.

Journal Article↗
PubMed1991

[Human placental lactogen levels in normal pregnancy monitored by serial ultrasound].

Parallel to the great use of ultrasound in diagnostical purposes the interest for biological effects of ultrasound is growing every day. The present studies of the biological action of ultrasound concerned the cytogenetic investigations as well as those of animals and men. Taking into account that the extrapolation of results from animals to men is uncertain all data obtained in human population are of utmost importance. We tried to define the possible biological action of routine diagnostical ultrasound on foetoplacental unit. Women with physiological pregnancy were exposed to ultrasound during regular antenatal control-examinations in the 20th, 30th and 38th week of gestation. The follow-up concerned HPL levels in the serum 1 hour before and 1 hour after exposure to ultrasound. There was no significant difference in concentrations of the examined hormone in both blood samples.

Embryonic and Fetal Development↗
PubMedDate not supplied

[Electroretinography findings in the other eye in patients with central retinal vein occlusion].

ERG assessment in 32 patients with recent OVCR was done over the period of 6 years. The aim was to check the hypothesis whether ERG values in the affected and "healthy" eye of the same patient are same. The control group consisted of patients of the same age but without eye disease. Scotopic "b" wave and photopic b/a ratio, known as indicators of oxygenation of the retina, were studied. In bs wave and b/a ratio the statistically significant difference between the group with OVCR and the other groups was found. Other groups showed no significant differences. The hypothesis that OVCR associated with a systemic disease is necessarily accompanied with changes in the other eye, has been challenged. However, the safety of the other eye is not absolute.

Aged↗
PubMedDate not supplied

[Surgical treatment of destructive diseases of the cornea].

The role of surgery in destructive corneal disease is: to protect cornea; remove the cause of the disease; remove the altered tissue and transplant the healthy one; and to repair ocular surface. This can be achieved by penetrating keratoplasty, lamellar keratoplasty, sclerokeratoplasty, keratectomy, peritomy, conjunctival transplantation or keratoepithelioplasty. Some of the combinations of these surgical techniques in our hands are presented, and the relevant literature is reviewed.

Corneal Diseases↗