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991.
JH Dennis SB Mortazavi MJ French PJ Hewitt CR Redding 《Canadian Metallurgical Quarterly》1997,41(1):95-104
Topographical and quantitative features of medial thalamic neurons in which aspartate (ASP) or glutamate (GLU) might act as neurotransmitters were investigated in the rat. The calcium-binding protein calbindin D-28k (CB) was exploited as a marker of neuronal subsets, thus allowing us to study also the relationships between the CB-containing neurons and those immunoreactive to excitatory amino acids. Double immunocytochemistry of ASP and CB or GLU and CB was performed in 40-microm-thick sections. The three markers were distributed in the thalamic midline, mediodorsal, anterior intralaminar and ventromedial nuclei, with regional variations. ASP-immunoreactive neurons appeared more numerous than the GLU-immunoreactive ones throughout these structures; ASP-CB or GLU-CB double-immunostained neurons were evident. ASP-, GLU- and CB-immunoreactive cells were then quantitatively evaluated in 5-microm-thick consecutive sections. Interindividual variations and different anti-ASP and anti-GLU antibodies did not result in significant differences. ASP and GLU were not co-localized. Single ASP- or GLU-immunoreactive neurons accounted for 60% of the total number of immunostained cells, and single ASP-immunopositive cells represented more than half of these neurons. Among the CB-immunoreactive cells (40% of the total), half were double immunostained; the proportion of double CB-ASP-immunopositive neurons was sevenfold higher than that of the CB-GLU-immunoreactive ones. These results indicate that ASP may act as excitatory neurotransmitter in a relatively high proportion of medial thalamic neurons, in which ASP frequently coexists with CB. Approximately 50% of the CB-immunoreactive cells did not contain either ASP or GLU, suggesting that some medial thalamic neurons may utilize a different neurotransmitter. 相似文献
992.
993.
994.
ML Anthony BC Sweatman CR Beddell JC Lindon JK Nicholson 《Canadian Metallurgical Quarterly》1994,46(1):199-211
The computer-based pattern recognition procedures of nonlinear mapping and principal-component analysis have been applied to analyze 1H NMR-generated metabolic data on the biochemical effects of 15 acute nephrotoxin treatments affecting the renal cortex and/or renal medulla in rats. The 1H NMR signal intensities for 16 urinary metabolites representative of several major intermediary biochemical pathways were estimated using either a simple semiquantitative scoring system or complete peak intensity quantitation. NMR-derived data were treated as input coordinates in a multidimensional metabolic space and were analyzed by pattern recognition methods through which the dimensionality was reduced for display and categorization purposes. Different nephrotoxin treatments were initially classified using semiquantitative metabolite scores on the basis of their 1H NMR-detectable biochemical effects, and a good separation of renal cortical toxin treatments from renal medullary toxin treatments was achieved. The refinement of using exact peak heights rather than metabolic data scores utilized the available metabolic information more fully and provided a unique classification of each type of toxin according to its pattern of biochemical effects and site of toxic action. Principal-component analysis provided consistently better results than did nonlinear mapping in terms of discrimination between different sites of toxicity, and maps generated from correlation matrices gave improved discrimination, compared with those based directly on the original metabolic data. A comparison between the use of an added internal quantitation standard (3-trimethylsilyl-[2,2,3,3-2H4]-1-propionate) and independently determined glucose excretion rates for scaling to the NMR-detected urinary glucose levels demonstrated that the consistent classification of site-specific nephrotoxicity was independent of the quantitation standard used. This study has provided a rigorous assessment of data processing, relative quantitation, and pattern recognition methods, and the utility of applying these methods to the classification of NMR-derived toxicological data. The considerable potential of the NMR-pattern recognition approach in the assessment of nephrotoxicity has also been confirmed with the discovery of new combinations of molecular markers of renal cellular damage. 相似文献
995.
Most reports on dermolipomas describe the serious complications arising from their removal. The aim of this article was to describe a safe and effective method of removing dermolipomas. Forty-five consecutive eligible patients underwent surgical removal of their dermolipomas over a 20-year period. Of the two complications, only one, a restrictive symblepharon, required further surgery. The techniques for excising simple dermolipomas and dermolipomas associated with a deformity of the lateral canthal angle are described. Safe removal of dermolipomas may be accomplished with minimal resection of the conjunctiva, including the pilosebaceous area, identification of contiguous structures, and removal of only that portion of the dermolipoma anterior to the lateral orbital rim. 相似文献
996.
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998.
CE Parker S Nightingale GP Taylor J Weber CR Bangham 《Canadian Metallurgical Quarterly》1994,68(5):2860-2868
CD8+ T cells were freshly isolated from a human T-cell leukemia virus type I (HTLV-I)-infected patient with tropical spastic paraparesis. These cells, which were specific for HTLV-I Tax, simultaneously recognized a minimum of five, and possibly as many as seven, distinct peptide epitopes within the protein. A further Tax epitope was recognized after a short period of culture without exogenous peptide stimulation. All but one of these epitopes were clustered in the N-terminal third of Tax, and one of the epitopes was clearly immunodominant on two separate occasions of testing. Recognition of the immunodominant epitope was restricted by human leukocyte antigen (HLA) B15, and recognition of all the others was by HLA A2. Similar patterns of cytotoxic T lymphocyte recognition of the HLA A2-restricted Tax peptides in two healthy HTLV-I-seropositive individuals, each of whom carried the HLA A2 allele, were observed. 相似文献
999.
1000.
D Gur DA Rubin BH Kart AM Peterson CR Fuhrman HE Rockette JL King 《Canadian Metallurgical Quarterly》1997,10(3):103-107
Results are submitted of clinical and immunological investigation conducted in 30 pregnant women whose therapeutic programme incorporated acupuncture procedures apart from a complex of conventional antianemic measures. There have been examined pregnant women with varying degree anemia over different time periods of their pregnancy course. Antianemic treatment using acupuncture procedures in pregnant women with iron deficiency anemia was found to significantly activate the state of both cell-mediated and humoral immunity, mobilizing defensive and adaptive bodily reactions, being an efficient option designed to preserve the pregnant women's immunologic tolerance in the system mother-fetus. 相似文献