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171.
Four cases of acute ileal diverticulitis are presented wherein early diagnosis helped avoid emergent surgery. All patients did well initially with conservative medical management. Acute ileal diverticulitis, although uncommon, should be suspected when the clinical presentation indicates an inflammatory condition of the lower right abdomen. Surgery, when required for recurrent disease, can be reserved for the interval between acute episodes. 相似文献
172.
PC Kouretas RL Hannan NK Kapur R Hendrickson EM Redmond AK Myers YD Kim PA Cahill JV Sitzmann 《Canadian Metallurgical Quarterly》1998,30(12):2669-2682
Heparin, which is widely used clinically, has recently been shown to have specific properties affecting the vascular endothelium. We hypothesized that heparin stimulates endothelial nitric oxide synthase (eNOS) activity by a mechanism independent of its anticoagulant properties and dependent on an inhibitory guanine nucleotide regulatory protein (Gi). We determined the effect of both heparin and N-acetyl heparin (Non-Hep), a heparin derivative without anticoagulant properties, on eNOS activity in cultured bovine aortic endothelial cells and on endothelium-dependent relaxation in isolated vascular rings. The eNOS activity was determined by measuring both citrulline and nitric oxide (NO) metabolite formation. Heparin and Non-Hep dose-dependently increased basal eNOS activity (ED50 1.0 microgram/ml or 0.15 U/ml), an effect that was significantly inhibited by pertussis toxin (100 ng/ml), a Gi-protein inhibitor. Agonist-stimulated (acetylcholine, 10 microM) eNOS activity was potentiated following pre-treatment with both heparin and Non-Hep and reversed by pertussis toxin. Heparin and Non-Hep induced a dose-dependent relaxation in preconstricted thoracic aortic rings, an effect that was significantly inhibited by pertussis toxin, endothelial inactivation (following treatment with sodium deoxycholate) and NG-nitro-L-arginine-methyl ester (L-NAME). We conclude that heparin and non-anticoagulant heparin induce endothelium-dependent relaxation following activation of eNOS by a mechanism involving a Gi-protein. Administration of heparin derivatives without anticoagulant properties may have therapeutic implications for the preservation of eNOS in conditions characterized by endothelial dysfunction. 相似文献
173.
S Singh IP Korah SV Gibikote NK Shyam A Nair A Korula 《Canadian Metallurgical Quarterly》1998,27(9):518-521
We present a case of primary hydatid disease of the sacrum. The diagnosis was made on MR imaging obtained to evaluate the spine for recurrent disc disease. The patient had previously undergone laminectomy elsewhere for L4-5 radiculopathy. Ultrasound-guided aspiration and visualisation of scolices confirmed the diagnosis. No other site of involvement was found. 相似文献
174.
AS Shashkov SN Senchenkova FV Toukach A Ziolkowski NA Paramonov W Kaca IuA Knirel' NK Kochetkova 《Canadian Metallurgical Quarterly》1996,61(9):1554-1562
An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Proteus mirabilis O10 and studied after full acid hydrolysis and carboxyl reduction by 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected heteronuclear 1H,13C multi-quantum coherence (HMQC), and rotating-frame nuclear Overhauser effect spectroscopy (ROESY). It was found that the polysaccharide contains 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, D-galacturonic acid, and L-altruronic acid, and the following structure of the branched tetrasaccharide repeating unit of the polysaccharide was established: [sequence: see text] 相似文献
175.
R. V. Vasil’eva E. A. D’yakonova A. V. Erofeev T. A. Lapushkina 《Technical Physics Letters》1998,24(7):562-564
An experimental investigation was made of the evolution of ionization instability in a model of a disk-shaped Faraday magnetogasdynamic
channel connected to a shock tube in a pure rare gas (xenon) with an alkaline additive. The main components of the average
electron energy balance were determined: the Joule heating power, the average rate of energy transport of the heavy component
by elastic collisions, and the average rate of energy lost through ionization. It was found that the electron energy defect
which includes losses not taken into account, increases abruptly at supercritical values of the magnetic induction and accounts
for approximately half of the Joule heating power. It is concluded that some of the electron energy is transferred to pulsations.
Pis’ma Zh. Tekh. Fiz. 24, 48–53 (July 26, 1998) 相似文献
176.
Genetic analysis of the population structure of the western blacklegged tick, Ixodes pacificus Cooley & Kohls, was conducted using allozymes. This vector tick transmits the Lyme disease spirochete, Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner, in the far-western United States. It ranges from British Columbia to Baja California and disjunct populations are present in Oregon, Nevada, Utah, and Arizona. Host-seeking adult ticks were collected from vegetation across the range of the species and were partially fed on rabbits prior to analysis. Twelve putative loci were resolved using starch gel electrophoresis. One locus, glucose-6-phosphate isomerase, formed an apparent north/south latitudinal cline and showed significant geographic structure. None of the remaining loci exhibited much genetic differentiation. Estimates of gene flow were high relative to other arthropods. Isolation-by-distance analysis suggests a recent and rapid range expansion. We conclude that the overall lack of differentiation is due high rates of gene flow. 相似文献
177.
178.
Radiographic findings associated with small talar dome fractures were analyzed in 21 patients. Representative cases are presented. The classification of talar dome fractures, and the role of the radiologist in their evaluation, are discussed. 相似文献
179.
180.