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Y Talmon

Publications and source records attributed to Y Talmon.

7 recordsLinked to original sources
PubMed1992

A temperature-jump device for time-resolved cryo-transmission electron microscopy.

We describe a temperature-jump device that permits time-resolved studies of thin cryo-transmission electron microscopy specimens. The specimen is rapidly heated to induce a change in microstructure just prior to cryo-fixation. The apparatus consists of a xenon arc lamp equipped with a shutter controlled by timing circuitry, used in conjunction with an environmental specimen preparation chamber. The specimen is heated by exposure to focused light from the lamp, and then plunged into cryogen. Using a thermocouple constructed from an electron microscope grid, we show that temperature jumps of 30-60 K are achieved with exposure times of 150-450 milliseconds. Micrographs of dimyristoyl phosphatidylcholine (DMPC) vesicles and n-docosane films, subjected to these exposures, show that the specimens are still at least 20-30 K above their initial temperature when they contact the cryogen. This method could be applied to a variety of biological and chemical systems which undergo structural changes activated by a rise in temperature.

Dimyristoylphosphatidylcholine↗
PubMed1992

["Saddam syndrome:" acute psychotic reactions during the Gulf War--renewal of concept of brief reactive psychosis].

6 patients came to our psychiatric emergency room during the first 2 weeks of the Gulf War presenting the clinical picture of acute delusional paranoid psychosis (4 women and 2 men between the ages of 30-77). 4 were without previously known psychopathology, while the other 2 were known to have had some nonpsychotic cognitive impairment. The first 4 recovered completely within a short time while the other 2 continued to have psychopathological symptoms. We discuss psychogenic or reactive psychosis, and the concept of reactivation when cumulative trauma exceed the individual's personal threshold, as may occur during a war. Different phenomenological syndromes may follow.

Acute Disease↗
PubMed1992

[Combined tricyclic antidepressants and ritalin in elderly depressives].

Psychostimulants, including ritalin (methylphenidate), were used as antidepressives in the '50s but were then replaced by tricyclics and MAO inhibitors. Treatment of depression with psychostimulants is still controversial. Several anecdotal reports in the past decade approved the use of tricyclic antidepressants (TCA) together with methylphenidate in apathetic and withdrawal states in medically ill and in elderly patients. Ritalin elevates mood by releasing catecholamines and blocking their re-uptake, and also increases serum TCA levels. 5 men and 5 women between the ages of 65 and 79 were diagnosed as suffering from major depressive disorders, either single or recurrent, based on the Revised Diagnostic and Statistical Manual for Mental Disorders (DSM-III-R). They had been treated with TCA for up to several months with no response. Following addition of methylphenidate, 5-15 mg/d for 2 weeks, 4 men and 3 women improved rapidly, 2 of them within 24 hours.

Aged↗
PubMed1991

Physico-chemical characterization of Intralipid emulsions.

Fat emulsions containing soy triacylglycerols (100-300 g/l) and egg-yolk phospholipids (12 g/l) are often used for intravenous feeding. Previous studies have shown that these emulsions contain chylomicron-like emulsion particles of diameters of 300-400 nm and excess phospholipids aggregated as vesicles (liposomes), which remain in the infranatant upon floatation of the emulsion particles by ultracentrifugation. This work is devoted to the characterization of the commercial lipid emulsions commonly denoted Intralipids, with special emphasis on the presently ill-defined liposomes. The lipid particles composing commercial lipid emulsions (10%, 20% and 30% Intralipids, Kabivitrum Nutrition) were characterized by the combined use of physical and chemical methods. Each of the emulsions was fractionated by ultracentrifugation in saline into a 'cream' layer which floats to the top of the dispersion upon ultracentrifugation and a relatively transparent infranatant. The cream layer contains large emulsion particles of diameters ranging from 300 to 400 nm, in agreement with theoretical considerations based on their chemical composition as determined by chemical analysis. The infranatants contain about 1 g/l triacylglycerols in addition to phospholipids (from 7.2 g/l in 10% Intralipid to 2.4 g/l in 30% Intralipid) in the form of smaller particles of 70-100 nm diameter. Cryo-transmission electron microscopy shows that the infranatants contain vesicles (mostly unilamellar) at the side of residual small emulsion particles. This conclusion is also consistent with the distribution of phospholipids between outer and inner lamellae, as determined by 31P-NMR.

Fat Emulsions, Intravenous↗
PubMed1979

Primary lymphoma of the parotid gland.

Primary lymphomas of the salivary glands are very rare. Approximately fifty possible cases have been reported. Whether primary malignant lymphoma of the parotid gland is extranodular or not, is not yet clear. We describe two cases of primary lymphoma of the parotid gland and review the literature of this condition.

Aged↗
PubMed1978

Malignant lymphoma of the maxillary sinus.

Extranodular lymphoma is not frequent and primary lymphoma of the paranasal sinuses is rare. An unusual case of malignant lymphoma of the maxillary sinus in a boy, involving the C.N.S. is reported.

Adolescent↗