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M Bureau M Brun-Pascaud N Colas-Linhart P Vivet JJ Pocidalo 《Canadian Metallurgical Quarterly》1983,19(3):279-284
Vascular inflammatory response to hyperoxia (FIO2 greater than 0.98) was studied in awake jugular and carotid catheterized rats. Simultaneous i.v. injection of 125I albumin (125I A), 99mTc polymorphonuclear cells (99mTc PMN) and 51Cr red blood cells (51Cr RBC) allowed to study both the macromolecule exchange through vascular endothelium and the leukocyte uptake by several organs (liver, lungs, spleen) with respect to radiolabelled red blood cells, as an intravascular reference. Rats were exposed to O2 for 24, 38 and 45 h. They were anesthetized and killed by exanguination 15 to 120 min following the tracer injection. After 45 h exposure, the plasmatic 125I A half-life decreased significantly (158 +/- 42 min for the control; 106 +/- 34 min for the exposed animals). The ratio 125I A/51Cr RBC varied significantly in the lung. The iodinated albumin exchange through lung vascular endothelium was altered at the 24th h, with a significant difference reached by the 45th h. At the same time, the pulmonary decreasing curve of 99mTc/51Cr RBC ratio versus time was not not modified. In our experimental conditions, there was no detectable variation in the lung uptake and vascular transit of PMN cells. The discussion of the results must be related with the technics used in the present work when the albumin exchange increased. 相似文献
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The presence of a cardiodepressant factor of pancreatic origin has been reported in the plasma of experimental animals and man in a variety of shock states. It has been suggested that the depression of developed tension of the isolated cat papillary muscle may be caused by excess NaCl in the bathing medium rather than a specific cardiodepressant peptide. Incubated pancreatic homogenate was used as a source of this factor, and after protein precipitation, ultrafiltration (10,00 and 1,000 MW), dialysis and lyophilization, the residue was applied to a Sephadex G-10 column in order to ensure the removal of all salts. The protein effluent of the Sephadex column contained all the cardiodepressant activity of the filtered, dialyzed pancreatic homogenate and none of the salt content. To further isolate this cardiodepressant factor, the active residue was applied to a cellulose column and eluted with butanol: glacial acetic acid: water (25:26 v/v/v). This elution gave 8 distinct peptide peaks, one of which, peak 4, contained significant depressant activity. Thus, a cardiodepressant peptide of approximately 250-1,000 MW exists in pancreatic homogenates and this compound is not excess NaCl in the assay system. 相似文献
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BACKGROUND AND OBJECTIVE: The use of topical anesthetic cream in the periorbital region may be of clinical value. The potential for toxic effects from such use has not been studied in a controlled manner. This study was performed to evaluate the potential ocular toxicity of anesthetic cream topically applied to the eyelid in an animal model. MATERIALS AND METHODS: Ten rabbits underwent periorbital eutectic mixture of local anesthetics (EMLA) (2.5 percent lidocaine and 2.5 percent prilocaine) application and were observed for evidence of gross or microscopic ocular toxicity. Baseline external and anterior segment examinations were performed, including biomicroscopy and fluorescein staining, after which a standard quantity of EMLA cream (0.75 g) was applied along the upper eyelid and covered with an occlusive dressing. After 1 hour of treatment, the eyelid and anterior segment were examined for evidence of adverse reaction. The eyelids were excised and examined histopathologically. RESULTS: No significant adverse effects were noted on external lid and anterior segment examination. The histopathologic findings were within normal limits. CONCLUSIONS: This study suggests that external application of EMLA cream to the eyelid does not induce local toxicity in the rabbit model. The external application of EMLA cream may be safe in the periorbital region. 相似文献
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