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BACKGROUND: Surgical defects of the central upper lip (philtrum) are a particularly difficult area to achieve satisfactory cosmetic and functional repair. Reconstruction of the central upper lip has been accomplished primarily through the use of side-to-side closure, bilateral advancement or rotation flap, and full-thickness graft. Repair may be complicated by distortion of the vermilion border, obliteration of the normal contour of the philtrum, eclabium, and trapdooring of the flap. OBJECTIVE: We review the options for reconstruction of this area and describe our experience using an island pedicle flap to complete reconstruction. METHODS: Four patients presented with basal cell carcinomas of the mid upper lip (philtrum). Tumors were cleared by Mohs micrographic surgery. Reconstruction was achieved by island pedicle flaps utilizing donor tissue from the superior philtrum. RESULTS: The patients had excellent cosmetic results with minimal distortion of the vermilion border or obliteration of the philtrum or philtral ridges. Scars healed in a nearly imperceptible fashion, keeping within one cosmetic unit (the philtrum) without extending along the vermilion border as seen in bilateral advancement or rotation flaps. CONCLUSIONS: Island pedicle flaps may be an effective cosmetic and functional repair of selected surgical defects of the central upper lip involving the philtrum. 相似文献
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CG Salomon CL Kalbhen CM Dudiak MC Olson ME Flisak RC Flanigan 《Canadian Metallurgical Quarterly》1998,206(2):533-538
The effects of denervation of central noradrenergic system on the interpartner relationships of adult cats were examined in a predatory test in the competitive situation for paired animals. Direct administration of the noradrenaline neurotoxin, N-2-chloroethyl-N-ethyl-2-bromobenzylamine (DSP-4 12 microg) into the medial forebrain bundle (MFB) of submissive cats changed previously established dominant-submissive relationship. Biochemical analysis demonstrated a significant reduction of noradrenaline (NA) concentration in the hypothalamus (AH), amygdala (AM), hippocampus (HC), and frontal cortex (CTX), and elevation of NA content in the midbrain central gray matter (CG) in MFB-lesioned cats. Simultaneously, DSP-4-induced lesions exerted significant decrease of 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) content in AH, CG, HC and CTX, and increased GABA level in AH, CG, AM, and HC. These results suggest that a coincident decrease of NA metabolism and increase of GABA metabolism led to fear drive reduction. 相似文献
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SA Sweeney RC Kelly JA Bourland T Johnson WC Brown H Lee E Lewis 《Canadian Metallurgical Quarterly》1998,22(6):418-424
Human hair was collected from the occipital crown region of the head from several subjects; these hair samples were presumptively positive for amphetamines by a previously evaluated immunoassay. Hair was washed briefly with methanol to remove external contamination, then extracted with hot methanol for 2 h to recover the drugs. The extracts were evaporated to dryness, reconstituted in buffer, and analyzed using a new enzyme-linked immunosorbent assay (ELISA) technique adapted for the detection of amphetamines in hair. Gas chromatography-mass spectrometry was used as the reference technique. Cross-reactivity of several related compounds was evaluated by equating the inverse of the ligand concentration at 50% antibody binding to the affinity constant for each compound. The ratio of a compound's affinity constant to that for d-methamphetamine was used to derive percent crossreactivity. These experiments yielded values of 30.8% for d-amphetamine, 7.4% for I-methamphetamine, 4.3% for phentermine, 2.9% for I-amphetamine, and <1% for ephedrine, methylenedioxyamphetamine, and methylenedioxymethamphetamine. Cross-reactivity of unrelated compounds was found to be non-existent. The optimum cutoff concentration was determined by receiver operating characteristic curve analysis to be 300 pg/mg and the observed limit of detection was 60 pg/mg. Intra-assay precision at 300 pg/mg was 3.3% (coefficient of variation, CV), and the interassay CV was 10.5%. The sensitivity and specificity of the method were 83% and 92%, respectively. 相似文献
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RS Poston M Ennen J Pollard EG Hoyt ME Billingham RC Robbins 《Canadian Metallurgical Quarterly》1998,116(3):386-396
There continues to be considerable effort towards the construction of compound libraries targeted for the inhibition of protease enzymes. New tag-encoding methods for library deconvolution have been applied to this problem and there has been particular interest in novel solid-phase linkers for the introduction of key pharmacophore groups required for protease inhibition. Recent reports have tended to focus on nonpeptidic libraries, and, notably, structure-based design methods are now being applied to direct library design. 相似文献