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These studies examined the role of (+)-methamphetamine ((+)METH) administration route on spontaneous behavioral activity vs. time relationships, and pharmacokinetic mechanisms for differences in effects. Male Sprague-Dawley rats (n=6 per administration route) received saline and three doses (0.3, 1.0 and 3.0 mg/kg) of (+)METH in a mixed-sequence design by intravenous (iv), subcutaneous (sc) or intraperitoneal (ip) administration. Locomotion and stereotypy were quantified by video-tracking analysis. The effects of (+)METH on spontaneous behavior were dose- and route-dependent. In particular, total locomotor activity was greatest following 3.0 mg/kg intraperitoneally (P<0.05) and stereotypy ratings were greatest following 3.0 mg/kg subcutaneously (P<0.05). In addition, the duration of locomotor effects was greatest after 3.0 mg/kg subcutaneously (P<0.05). Serum pharmacokinetic parameters were determined in separate rats given 3.0 mg/kg by subcutaneous and intraperitoneal administration (n=4 per administration route). The (+)METH elimination half-life was not different between the routes, but the (+)METH AUC was greater (P<0.05), and the (+)METH and (+)-amphetamine (AMP) maximum concentrations occurred later following subcutaneous than after intraperitoneal dosing (P<0.05), increasing and prolonging drug exposure. In conclusion, the overall pattern of (+)METH effects on locomotor activity depend on dose and the route of administration, which affects serum concentration and the time course of behavioral effects.  相似文献   
996.
Percutaneous coronary intervention (PCI) in acute myocardial infarction (MI) has been associated with a high incidence of slow-, no-reflow. The slow-, no-reflow phenomenon is known to complicate both thrombolytic therapy and PCI. Removing intracoronary thrombus before PCI in acute MI patients may reduce the incidence of slow-, no-reflow phenomena. We studied the procedural outcome of 21 patients who underwent rheolytic thrombectomy using Possis® rheolytic thrombectomy catheter in the setting of acute MI as compared to twenty-eight patients who underwent PCI in the setting of acute MI using other modalities (PTCA with or without stenting) without thrombectomy. The study included 49 consecutive patients with 21 patients in the rheolytic thrombectomy group, and 28 patients in the no-rheolytic thrombectomy group. There was no significant difference between the two groups as regards to gender, age, and prevalence of coronary artery risk factors. The left ventricular ejection fraction was 44.7 ± 12 in the rheolytic thrombectomy group, and 37.6 ± 10.8 in the no-rheolytic thrombectomy group (p = 0.08). Thirty eight percent of the patients in the rheolytic thrombectomy group experienced slow flow, no-reflow, while 28.6% of the patients in the no-rheolytic thrombectomy group experienced slow flow, no-reflow (p = 0.5). In this matched series of patients with acute MI undergoing PCI, rheolytic thrombectomy by the Possis rheolytic thrombectomy catheter device does not appear to reduce the risk of slow flow, no-reflow, or in-hospital death, compared to standard PTCA and stenting of the infarct-related artery.  相似文献   
997.
Endoscopic features of esophageal tuberculosis   总被引:5,自引:0,他引:5  
BACKGROUND: Esophageal tuberculosis is rare. Clinical and endoscopic features are variable, diverse, nonspecific, and poorly described. These findings may be confused with those of esophageal cancer and deep fungal infection. METHODS: Medical records from a 5-year period (January 1997 to December 2001) were searched for cases of esophageal tuberculosis. For identified cases, the clinical, radiologic, and endoscopic features were evaluated. OBSERVATIONS: Four cases of esophageal tuberculosis were encountered during the 5-year period studied. Three of the patients presented with dysphagia and weight loss. One patient had aspiration pneumonia and another fatal hematemesis. Endoscopic features included deep and large proximal esophageal ulcers in 2 patients, tracheo-esophageal fistula in one, and nonhealing proximal esophageal ulcer in another patient. CONCLUSION: The present case series indicates that certain endoscopic features, such as deep and large esophageal ulcers, tracheoesophageal fistula, and nonhealing ulcer, are strongly suggestive of tuberculosis-related esophageal lesions.  相似文献   
998.
Chylothorax after myocardial revascularization is a rare but serious complication. There is as yet no definitive treatment. We report a case in which chylothorax was diagnosed on the 3rd postoperative day. Conservative management with dietary restriction to medium-chain triglyceride led to reduction of chyle leakage from 300 to 400 mL/day to 50 to 60 mL/day 3 days later. However, the leak persisted until talc pleurodesis was performed.  相似文献   
999.
Bening fibrous histiocytoma is one of the most frequent benign tumors. Most tumors are found in the skin, particularly on the limbs. Tumor size is usually small. According to the WHO, a deep location is found for less than 1% of all benign fibrous histiocytomas. Most deep tumors occur in the subcutaneous tissue. Deep locations in other organs have also been reported. We report a case and discuss the pathological and clinical aspects of this rare tumor.  相似文献   
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