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51.
GV Matiushin VA Shul'man AI Balog SE Golovenkin OV Smirnova 《Canadian Metallurgical Quarterly》1998,70(9):71-73
AIM: To investigate the effectiveness of superfrequent transesophageal left atrial stimulation (TLAS) and its combination with cordarone in management of atrial flutter (AF). MATERIALS AND METHODS: 650 patients with paroxysmal AF underwent TLAS. The paroxysm duration varied from 1 hour to 1 month. In 312 patients TLAS was performed prior to treatment with antiarrhythmic drugs (group 1), in 338 patients--after intravenous administration of cordarone (group 2). RESULTS: Superfrequent TLAS has restored sinus rhythm (SR) in 85(27.2%) and 169(50%) patients of groups 1 and 2, respectively (p < 0.001). TLAS promoted conversion of AF in atrial fibrillation (AFi) in 185(59.3%) and 159(47.1%) patients of groups 1 and 2, respectively (p < 0.01). Moreover, SR recovered 24-48 hours after TLAS in 87(27.9%) and 64(18.9%) patients of groups 1 and 2 respectively (p < 0.01). Sinus rhythm recovered in a total of 172(55.1%) and 233(69.0%) patients, AF was converted to AFi in a total of 88(31.4%) and 95(28.1%) patients (p > 0.05) of groups 1 and 2, respectively. TLAS was uneffective in 42(13.5%) and 10(2.9%) patients of groups 1 and 2, respectively. CONCLUSION: Superfrequent TLAS is a highly effective and non-invasive modality in the treatment of paroxysmal AF. It promotes recovery of SR. In some patients TLAS induces AFi which is more controllable by medication as regards the heart rate. Cordarone contributes to the response to TLAS in patients with paroxysmal AF. 相似文献
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A portable magnetometer to determine magnetic field anomalies is described. The block diagram of the magnetometer and its specifications are presented. 相似文献
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A Parent K Schrader SD Munger RR Reed DJ Linden GV Ronnett 《Canadian Metallurgical Quarterly》1998,79(6):3295-3301
Field potential recording was used to investigate properties of synaptic transmission and long-term potentiation (LTP) at Schaffer collateral-CA1 synapses in both hippocampal slices of mutant mice in which the alpha-subunit of the olfactory cyclic nucleotide-gated channel (alpha3/OCNC)1 was rendered null and also in slices prepared from their wild-type (Wt) littermates. Several measures of basal synaptic transmission were unaltered in the OCNC1 knockout (KO), including maximum field excitatory postsynaptic potential (fEPSP) slope, maximum fEPSP and fiber volley amplitude, and the function relating fiber volley amplitude to fEPSP slope and paired-pulse facilitation. When a high-frequency stimulation protocol was used to induce LTP, similar responses were seen in both groups [KO: 1 min, 299 +/- 50% (mean +/- SE), 60 min, 123 +/- 10%; Wt: 1 min, 287 +/- 63%; 60 min, 132 +/- 19%). However, on theta-burst stimulation, the initial amplitude of LTP was smaller (1 min after induction, 147 +/- 16% of baseline) and the response decayed faster in the OCNC1 KO (60 min, 127 +/- 18%) than in Wt (1 min, 200 +/- 14%; 60 min, 169 +/- 19%). Analysis of waveforms evoked by LTP-inducing tetanic stimuli revealed a similar difference between groups. The development of potentiation throughout the tetanic stimulus was similar in OCNC1 KO and Wt mice when high-frequency stimulation was used, but OCNC1 KO mice showed a significant decrease when compared with Wt mice receiving theta-burst stimulation. These results suggest that activation of cyclic nucleotide-gated channels may contribute to the induction of LTP by weaker, more physiological stimuli, possibly via Ca2+ influx. 相似文献
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To assess the relation between immunological disorders and recurrent abortion, 15 pregnant women with previous unexplained recurrent abortivity were submitted to serum screening for antiphospholyeid antibodies syndrome (APA) syndrome. The screening included specific tests for autoimmune diseases (ANA, specific organ antibodies, immune complexes research, etc.), the immunoenzymatic assay (ELISA) for the research of anticardiolipin antibodies (ACA) and the determination of the kaolin coagulation time (KCT) through Exener method for lupus anticoagulant (LAC). Nine gravids out of 15 were positive both to LAC and ACA antibodies, two gravids were positive to only ACA antibodies, while four had no antibody reaction. Therefore, whatever the effective mechanism is, it seems ascertained that several cases of unexplained recurrent abortion are related to APA syndrome. Nowadays the above-mentioned syndrome is successfully treated using corticosteroid immunosuppressors and platelet antiaggregators which reduce autoimmune reaction and thrombotic episodes. 相似文献
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Hand infections are common presentations among diabetic patients admitted to hospital in Tanzania. The morbidity and mortality are high and patients' hospital inpatient stay tend to be prolonged because of suboptimal therapy. We describe four diabetic patients with hand infections and fatal outcomes. In contrast to patients with foot infections, none of our patients had clinical evidence of peripheral neuropathy or vascular disease. All four patients eventually died in hospital after acquiring hand sepsis and diabetic ketoacidosis which did not respond to prolonged courses of intravenous insulin and antimicrobials. Literature review suggests such infections are at least as likely to include Gram-negative organisms as Staphylococcus aureus. Primary management should have included aggressive surgery with limb amputation if necessary with adjunctive antimicrobial therapy. 相似文献
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