C60 reacted with PhH, PhCl, BnH, BnNH2, and o-C2H2B10H10 in the electron impact (EI) ion source of a mass spectrometer at 300 °C forming phenyl, benzyl, and o-carboranyl adducts, respectively, stabilized by hydrogen addition and loss. Besides, the additions to C60 of methyl and phenyl radicals for toluene, and a phenyl radical for benzylamine were observed. A homolytic reaction mechanism was suggested involving the reaction of the radicals formed from the aromatics under EI with C60 at the ionization chamber walls.
View Article and Find Full Text PDFOur previous investigations showed that homolytic reactions of C(60) with a number of perfluoroorganic and organomercury(II) compounds occurring under electron impact (EI) in the ionization chamber (IC) of a mass spectrometer could predict the reactivity of C(60) towards these compounds in solution or solid state. To expand the scope of this statement, C(60) and C(70) have been reacted with ketones RCOR(1), where R and R(1) are alkyl, aryl, benzyl, and CF(3), in an IC under EI to yield products of the addition of R(·) and R(1)(·) radicals to the fullerenes, paramagnetic ones being stabilized by hydrogen addition and loss. Experimental evidence in support of a mechanism involving homolytic dissociation of ketone molecules via superexcited states to afford these radicals that react with the fullerenes at the IC surface has been obtained.
View Article and Find Full Text PDFThe regularities of mass spectrometric fragmentation under electron impact of new 9-(o-chlorobenzyl)-8-azahypoxantines with (N-aryl)amidocarbonylmethylthiomethyl substituents in position 2 were studied. The main fragmentation pathways are the elimination of Ar-NH+ and o-chlorobenzyl ions and cleavage of C-S bonds, characteristic of organic sulfides. During the fragmentations, some rearrangements occur, consisting in the transfer of labile hydrogen atoms from the alpha-positions to ions being eliminated.
View Article and Find Full Text PDFAn original variant of minimally invasive gastrostomy is described which is recommended for use in cases of a necessary temporary exclusion of the esophagus passage in patients with lesions of the esophagus in combination with a severe concomitant pathology.
View Article and Find Full Text PDFExperience of surgical treatment of 48 patients with postburn cicatricial gastric stenosis was presented. In 28 of them the combined gastric and esophageal stricture were reveal. Gastric resection according to Billroth-I was performed in 26 patients, gastroduodenostomy according to Finney--in 4, gastric resection according to Hoffmeister-Finsterer--in 5, gastroenterostomy according to Belfler-Brown--in 10 and other operations--in 3.
View Article and Find Full Text PDFWhile performing forceful esophageal bougienage for postburn cicatricial stricture its wall perforation have occurred in 9 of 57 patients. All the patients were operated on. For perforation of thoracic esophagus transabdominal transdiaphragmatic mediastinal drainage was performed and for subdiaphragmatic perforation--closure of the defect with Nissen fundoplication, gastrostomy with temporary conduction of ring--like guide fishing-line.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
July 2001
The paper presents results of dynamic and equilibrium surface tension measurements (using a maximum bubble pressure instrument) of serum and urine samples that were obtained from 80 healthy human of various sexes and ages. These data were compared with surface tension measurements of biological liquids obtained from patients suffering from malignant neoplasm of corpus uteri (n=5) and cervix uteri (n=31). In addition, surface dilatational rheology was determined on 32 samples using a drop shape method.
View Article and Find Full Text PDFChronic dust bronchitis in miners is associated with increase in dynamic surface tension of blood at short (t = 0.01 s) and medium (t = 1 s) surface lifetimes with lower declination angle of interphase tensiograms curve. Surface tension disorders were similar to those in experimental dust bronchitis.
View Article and Find Full Text PDFThe disease was simulated by inhalation of dust containing 29% of free silica in Wistar male rats during 8 months. One group of the subjects was kept under 26-28 degrees C and other one--under 38-40 degrees C. Dynamic surface tension of lung tissue homogenate was studied by means of computer tensiometer MRT (Lauda, Germany).
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