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Biomedical subjects

S Levene

Publications and source records attributed to S Levene.

24 records · Page 2Linked to original sources
PubMed1987

Human umbilical arteries and veins: generation of leukotrienes and response to exogenous leukotrienes.

When human umbilical arteries and veins were challenged with calcium ionophore A23187 they released a leukotriene (LT)-like material. On bioassay using guinea-pig ileal smooth muscle, the release was equivalent to 37.4 +/- 7.5 ng LTD4 (mean +/- SEM) per gram of arterial tissue, and 29.0 +/- 4.7 ng LTD4/g of venous tissue. The LT was further purified by high pressure liquid chromatography, and characterised as LTC4 by bioassay and radioimmunoassay of purified fractions. Longitudinal strips from human umbilical arteries in vitro did not contract to doses of synthetic LTD4 in the range 5 X 10(-11) to 10(-9) mol.

Humans↗
PubMed1986

Once daily theophylline in childhood asthma.

A new sustained-release theophylline preparation has been designed with the purpose of providing 24-hour protection against bronchospasm in asthmatics when given as a single dose. Fifteen children with moderate asthma completed a double-blind, placebo-controlled crossover trial of this product given once a day before bed. There was a significant fall in night symptoms (P less than 0.05), a rise in the mean early morning peak expiratory flow rate (PEFR) (P less than 0.01) and a fall in the number of mornings on which PEFR was less than 2 SD under the mean for height (P less than 0.01). An improvement in mean day symptom scores and evening PEFR was not significant. Thus we have shown that this product given once a day before bed is suitable for this way.

Asthma↗
PubMed1986

Generation of leukotrienes from fetal and neonatal porcine blood vessels.

Various blood vessels from fetal and neonatal piglets were challenged with calcium ionophore A23187, to examine the release of leukotriene-like material. All tissues released as much or more leukotriene (LT) than adult porcine tissues previously examined. The release fell with increasing gestational age. The release from the intra-abdominal umbilical vein at 11 days preterm (480 ng of LTD4-like activity per gram of tissue) was an order of magnitude higher than that previously observed. The implications with regard to control of the fetal circulatory pattern are discussed.

Animals↗
PubMed1977

Partial hepatectomies with a hand-held laser knife: An experimental study.

Fifteen mongrel dogs underwent a left lateral non-anatomical partial hepatectomy using a carbon dioxide laser, diathermy or a surgical scalpel. An original prototype of a compact hand-held laser was used and its effects were compared with those of the other two instruments. An improved dry cat surface was achieved by placing a rubber snare proximal to the planned incision. While no significant differences in the blood loss or in the operating time were found among the experimental groups, the laser beam sealed vessels of up to about 6 mm in diameter without any complementary suture ligatures, which were needed in the other groups. Histological studies revealed less tissue trauma in the sections performed by the laser and only slight secondary inflammatory reaction.

Animals↗