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41.
S Delorme A Dietz V Rudat I Zuna ML Bahner G van Kaick 《Canadian Metallurgical Quarterly》1997,23(9):1311-1317
This summary of the practice parameters describes the assessment, differential diagnosis, and treatment of children, adolescents, and adults who present with symptoms of attention-deficit/hyperactivity disorder. The rationales for specific recommendations are based on a review of the scientific literature and clinical consensus which is contained in the complete document. Assessment includes clinical interviews with the child and parents and standardized rating scales from parent and teachers. Testing of intelligence and academic achievement is usually required. Comorbidity is common. The cornerstones of treatment are support and education of parents, appropriate school placement, and psychopharmacology. The primary medications are psychostimulants, but antidepressants and alpha-adrenergic agonists are used in special circumstances. Other treatments such as behavior modification, school consultation, family therapy, and group therapy address remaining symptoms. 相似文献
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DE Anderson XJ Yuan CM Tseng LJ Rubin GM Rosen ML Tod 《Canadian Metallurgical Quarterly》1993,193(3):878-885
Free radicals react with nitrones to form stable nitroxides which can be identified by ESR spectroscopy. Unfortunately, little is known regarding the pharmacological properties of these compounds. In this study, three commonly used nitrones, 5,5-dimethylpyrroline-N-oxide (DMPO), alpha-phenyl-tert-butylnitrone (PBN), and alpha-(4-pyridyl 1-oxide)-N-tert-butylnitrone (POBN), were found to induce relaxation of preconstricted isolated rat pulmonary artery rings. Additional experiments with PBN indicated that vasorelaxation could not be attributed to production of endothelial derived factors, prostaglandins, or free radicals. Patch-clamp techniques revealed reversible calcium channel blockade with PBN at a concentration below that needed to detect free radicals. Calcium channel blockade probably accounts for the vasorelaxation observed in the isolated ring preparations described here, and should be considered when using nitrone spin-traps both in in vivo and clinical studies. 相似文献
44.
A case of Macrozamia riedlei seed poisoning is described in a young Dachshund. Vomiting and depression commenced within 6 h of ingestion; other signs that developed included severe hepatopathy, jaundice, abdominal pain that was unresponsive to analgesics, severe gastro-intestinal haemorrhage and thrombocytopenia as well as crystalluria and marrow dyserythropoiesis. The dog was euthanased 6 days after ingestion of the seeds. 相似文献
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ML Calladine 《Canadian Metallurgical Quarterly》1996,13(1):51-57
Laparoscopic ultrasound combines the advantage of diagnostic laparoscopy with intraoperative ultrasonography. This new technique allows visualisation of deep structures that are not palpable. The technical aspects and the application in abdominal surgery are described. The principal indications are detection of common bile duct stones during laparoscopic cholecystectomy and staging of abdominal cancers. The information provided by laparoscopic ultrasound influences therapeutic decisions. 相似文献
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MJ van den Brand A van Miltenburg MJ de Boer LR van der Wieken PJ de Feyter ML Simoons 《Canadian Metallurgical Quarterly》1994,10(3):177-185
Patients with unstable angina, refractory to intensive medical therapy, are at high risk for developing thrombotic complications, such as recurrent ischemia, myocardial infarction and coronary occlusion during coronary angioplasty. As both platelet aggregation and/or thrombus formation play an important role in this ongoing ischemic process, a monoclonal platelet GPIIb/IIIa receptor antibody (c7E3) or thrombolytic therapy (alteplase) might be able to modify the clinical course and underlying coronary lesion morphology. To evaluate whether alteplase or c7E3 could influence the incidence of complications, we randomized 36 and 60 patients, respectively to alteplase or placebo, or c7E3 or placebo. All patients exhibited dynamic ECG changes and recurrent pain attacks, despite maximal tolerated medical therapy. Patients were randomized in both studies after initial angiography had demonstrated a culprit lesion amenable for angioplasty. After study drug infusion quantitative angiography was repeated and angioplasty performed. Recurrent ischemia during study drug infusion occurred in 5, 6, 9 and 16 patients from the alteplase, placebo, c7E3 and placebo group, respectively. Major events defined as death, myocardial infarction or urgent intervention occurred in 7, 3, 1 and 7 patients, respectively. Two patients died: one in the alteplase group and one in the placebo group from the c7E3 study. The first patient due to retroperitoneal hemorrhage, the second as a result of recurrent infarction. Qualitative angiography showed resolution of clots in the c7E3 group only, while the same group of patients showed in 20% an improvement in TIMI flow grade, without deterioration in any patient from this group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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A previous pilot study demonstrated that a force and frequency-weighted filter network could be developed for processing continuous biomechanical measures of repetitive wrist motions and exertions. The current study achieves the objective by modelling subjective discomfort for repetitive wrist flexion using controlled posture, pace and force. A three-level fractional factorial experiment was conducted involving repetitive wrist flexion (2 s/motion, 6 s/motion, 10 s/motion) from a neutral posture to a given angle (10 degrees, 28 degrees, 45 degrees) against a controlled resistance (5 N, 25 N, 50 N) using a Box Behnken design. Ten subjects participated. Discomfort was reported on a 10 cm visual analogue scale. Results of response surface regression analysis revealed that main effects of force, wrist flexion angle, and repetition were all significant (p < 0.05) and that no second-order effects were observed. Linear regression analysis on these factors established a discomfort model on which the filter characteristics were based. The pure error test model revealed no significant lack of fit (p > 0.05). The continuous model was compared and agreed with discrete psychophysical data from other published studies. The model was used for generating parameters for a force and frequency-weighted digital filter that weighs continuous wrist postural signals with corresponding force in proportion to the equal discomfort function as a function of frequency of repetition. These filters will enable integration of large quantities of biomechanical data in field studies. 相似文献