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Biomedical subjects

R Schach

Publications and source records attributed to R Schach.

7 recordsLinked to original sources
PubMed2004

Formation of weak polyelectrolyte multilayers studied by spin labeling.

Multilayers of alternately adsorbing poly(allylamine) (PAH) and poly(acrylic acid) (PAA) of opposite charges on silica have been studied by the spin labeling technique, as a function of pH. The two polyelectrolytes have been labeled independently by a nitroxide free radical. Its electron paramagnetic resonance spectrum is mainly sensitive to the local Brownian motion and shows lines typical of two different environments, namely, loops protruding in solution with a fast motion and trains adsorbed on the solid with a hindered motion. These two parts have been evaluated for each of the polymer layers separately, and the thickness of the coatings has been described more precisely by characterizing the four contributions existing, for example, for a bilayer. Complexation is demonstrated by the loss of loops and tails belonging to the first polyelectrolyte. The overall picture emerging from the data is explained in terms of compensation of charges and entropy of confinement.

Journal Article↗
PubMed1988

Low dose heparin versus low molecular weight heparin (Kabi 2165, Fragmin) in the prophylaxis of thromboembolic complications of abdominal oncological surgery.

Eighty patients undergoing pelvic or abdominal surgery for cancer were randomized in two groups for prevention of postoperative thromboembolism: 40 patients received a 15,000 IU day-1 Calciparine prophylaxis and 40 patients a 5000 anti-Xa U/d Fragmin prophylaxis for 10 days. In the Calciparine group, two patients (5%) developed postoperative pulmonary embolism but none developed it in the Fragmin group. Two patients in the Fragmin group (5%) developed isotopic DVT, which was not confirmed by phlebography. There was no deep vein thrombosis of the lower limbs in the two groups. Important postoperative bleeding (one patient in the Calciparine group and two patients in the Fragmin group) was similar in both groups. Moderate and minor bleeding were significantly lower in the Fragmin group. Haemoglobin and haematocrit changes, total blood loss and transfusion requirements were not different in both groups. It is concluded that, over a 10-day period, one daily 5000 U Fragmin prophylaxis was as effective and safe as three daily 5000 IU Calciparine injections.

Abdominal Neoplasms↗
PubMed1981

[Clamped umbilical cord. Effect on the puerperium and the newborn's hematocrit].

This study investigated the effect of clamped and unclamped cord on third stage of labor in two patient groups and correlated the drained placental blood volume with the newborn hematocrit. In the first group (trial group, n = 215) the placental part of the cord was left unclamped and the drained blood volume was measured. In the second group (control group, n = 199) the placental part of the umbilical cord was left clamped. Both groups were nearly equal regarding history, age and parity. The following results were obtained: Unclamped umbilical cord was associated with a shorter third stage of labor, unclamped umbilical cord was associated with less blood loss during third stage of labor, unclamped umbilical cord was associated with fewer operative procedures (i.e. manual removal of the placenta), differences regarding the number of incomplete or possibly incomplete placentae were not evident, a highly significant negative correlate was found between placental blood volume drained from the umbilical cord and newborn hematocrit (r = 0.38; p less than 0.001).

Adult↗