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The incidence and patterns of and factors associated with inappropriate antibiotic use were studied in a tertiary care center in Thailand. The incidence of inappropriate antibiotic use was 25%. Admission to the surgical department (adjusted odds ratio, 2.0; P=.02) and to the obstetrics and gynecology department (adjusted odds ratio, 2.0; P=.03) were associated with inappropriate antibiotic use, whereas consultation with an infectious diseases specialist was protective against inappropriate antibiotic use (adjusted odds ratio, 0.15; P=.01).  相似文献   
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The objective of this study was to test the safety of withholding anticoagulant treatment and additional call-back diagnostic testing with ultrasound in patients who have a negative D-dimer at presentation. Patients with signs and symptoms of deep-vein thrombosis who presented to the emergency department after regular hours and on weekends underwent D-dimer testing using the STA-Liatest D-di. In patients with negative D-dimer results, heparin therapy was withheld, and no further diagnostic testing for deep-vein thrombosis was done as part of the initial evaluation. Patients with positive D-dimer results underwent compression ultrasonography. The primary outcome measure was a diagnosis of new symptomatic venous thromboembolism confirmed by diagnostic testing during the 3-month follow-up period. Of the 260 eligible patients, 81 (31%) had a negative D-dimer and 179 (69%) had a positive D-dimer. No patient with a negative D-dimer at presentation had confirmed venous thromboembolism at 3-month follow-up. Three patients died: one by intracranial hemorrhage secondary to cerebrovascular accident; and two deaths of indeterminate cause almost 3 months after entry. The automated assay for D-dimer, the STA-Liatest D-di, seems to provide a simple method with high clinical utility for excluding acute first-episode deep-vein thrombosis in symptomatic patients who present to the emergency room after regular hours.  相似文献   
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Six thrombin-generation inhibitors or thrombin inhibitors were compared in the extrinsic coagulation activity assay (EXCA), where the normal thrombin generation is about 1 IU/ml within 1 min (37 degrees C). Unfrozen pooled normal citrated plasma was supplemented on flat-bottom wells (23 degrees C) with increasing concentrations of dalteparin, danaparoid, heparin, fondaparinux, hirudin, or argatroban. To 50 microl plasma, 5 microl of 1.5 ng/ml tissue factor, 6% bovine serum albumin, and 250 mmol/l CaCl2 were added. After 1 and 2 min coagulation reaction time at 37 degrees C (EXCA-1 and EXCA-2), 100 microl of 2.5 mol/l arginine and 0.16% Triton X 100, pH 8.6, were added. After 3 min (23 degrees C), 25 microl of 1 mmol/l CHG-Ala-Arg-pNA in 1.25 mol/l arginine, pH 8.7, were added, and the linear increase in absorbance with time was determined at 405 nm. The 50% inhibitory concentrations of plasmatic anticoagulants tested in the EXCA-1 (37 degrees C) were 0.025 IU/ml dalteparin, 0.13 U/ml danaparoid, 0.12 IU/ml heparin, 1.3 microg/ml fondaparinux, 2.4 ng/ml hirudin, and 1 microg/ml argatroban. From the 50% inhibitory concentration of hirudin it can be concluded that inhibition of about 30 mIU/ml thrombin halves the normal EXCA-1 value (i.e. if about 0.1 IU/ml thrombin are inactivated, then thrombin cannot self-amplify its generation 10-fold). The efficiency of any clinically used plasmatic anticoagulant can be monitored in the EXCA.  相似文献   
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