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101.
Spontaneous spinal epidural hematoma (SSEH), is a rare and potentially fatal condition that responds favorably to early surgical intervention and should be considered in the differential diagnosis of spinal cord compression. There are few reported cases in children. We present a case of spontaneous spinal epidural hematoma in an 18-month-old child and review the literature. 相似文献
102.
KI Hirsch-Ernst S Gaini-Rahimi BP Ernst C Schmitz-Salue S Blume GF Kahl 《Canadian Metallurgical Quarterly》1998,249(1):151-155
After feeding a commercial rodent chow for 8 weeks, tissues from male and female rats were collected and examined for selenium content, glutathione peroxidase (GPX) activities and selenoprotein W (Se-W) levels. There were no differences (P > 0.05) between plasma selenium content, plasma GPX activity, whole blood selenium content, or whole blood GPX activity between male and female rats. There was also no gender effect on selenium concentration in muscle, brain, spleen, and skin, but selenium concentration in liver was higher (P < 0.05) in female than in male rats. Western blots indicated that the tissue distribution of Se-W was similar in male and female rats. Se-W protein level was high in testes of male rats but very low in ovaries of female rats. Muscle and skin from female rats had significantly higher (P < 0.05) Se-W levels than from male rats. Consistent with Se-W content, the Se-W mRNA levels from female skins were significantly higher (P < 0.05) than from male rats. The expression of Se-W was different in various tissues and gender influenced this regulation in some tissues. 相似文献
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LM Barone HH Mu CJ Shih KB Kashlan BP Wasserman 《Canadian Metallurgical Quarterly》1998,118(1):315-322
Plasma membrane vesicles from red beet (Beta vulgaris L.) storage tissue contain two prominent major intrinsic protein species of 31 and 27 kD (X. Qi, C.Y Tai, B.P. Wasserman [1995] Plant Physiol 108: 387-392). In this study affinity-purified antibodies were used to investigate their localization and biochemical properties. Both plasma membrane intrinsic protein (PMIP) subgroups partitioned identically in sucrose gradients; however, each exhibited distinct properties when probed for multimer formation, and by limited proteolysis. The tendency of each PMIP species to form disulfide-linked aggregates was studied by inclusion of various sulfhydryl agents during tissue homogenization and vesicle isolation. In the absence of dithiothreitol and sulfhydryl reagents, PMIP27 yielded a mixture of monomeric and aggregated species. In contrast, generation of a monomeric species of PMIP31 required the addition of dithiothreitol, iodoacetic acid, or N-ethylmaleimide. Mixed disulfide-linked heterodimers between the PMIP31 and PMIP27 subgroups were not detected. Based on vectorial proteolysis of right-side-out vesicles with trypsin and hydropathy analysis of the predicted amino acid sequence derived from the gene encoding PMIP27, a topological model for a PMIP27 was established. Two exposed tryptic cleavage sites were identified from proteolysis of PMIP27, and each was distinct from the single exposed site previously identified in surface loop C of a PMIP31. Although the PMIP31 and PMIP27 species both contain integral proteins that appear to occur within a single vesicle population, these results demonstrate that each PMIP subgroup responds differently to perturbations of the membrane. 相似文献
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CA Bernhart PM Perreaut BP Ferrari YA Muneaux JL Assens J Clément F Haudricourt CF Muneaux JE Taillades MA Vignal 《Canadian Metallurgical Quarterly》1993,36(22):3371-3380
Starting from the structure of the novel nonpeptide AT1 receptor antagonist DuP 753 (losartan), a new series of potent antagonists was designed. In these compounds the central imidazole nucleus was replaced by the dihydroimidazol-4-one structure. The most active compounds had a spirocyclopentane or a spirocyclohexane ring in position 5. Like the imidazole series, the best substituents were the linear butyl chain in position 1 and the [2'-(tetrazol-5-yl)biphenylyl]methyl group in position 3. Antagonistic activity was assessed by the ability of the compounds to competitively inhibit [125I]AII binding to the AT1 subtype receptor and to antagonize AII-induced contractions in rabbit aorta rings. The most active compounds had IC50 values in the nanomolar range. In conscious rats, compounds 4 and 21 antagonized the AII pressor response when administered orally. Compound 21 (SR 47436) was the most active; it was recently shown to also be active in cynomolgus monkeys both intravenously and orally. This molecule is now undergoing clinical trials for the treatment of hypertension. 相似文献
109.
M Sukumar M Bommaraju JE Fisher FC Morin MC Papo BP Fuhrman LJ Hernan CL Leach 《Canadian Metallurgical Quarterly》1998,84(1):327-334
Partial liquid ventilation using conventional ventilatory schemes improves lung function in animal models of respiratory failure. We examined the feasibility of high-frequency partial liquid ventilation in the preterm lamb with respiratory distress syndrome and evaluated its effect on pulmonary and systemic hemodynamics. Seventeen lambs were studied in three groups: high-frequency gas ventilation (Gas group), high-frequency partial liquid ventilation (Liquid group), and high-frequency partial liquid ventilation with hypoxia-hypercarbia (Liquid-Hypoxia group). High-frequency partial liquid ventilation increased oxygenation compared with high-frequency gas ventilation over 5 h (arterial oxygen tension 253 +/- 21.3 vs. 17 +/- 1.8 Torr; P < 0.001). Pulmonary vascular resistance decreased 78% (P < 0.001), pulmonary blood flow increased fivefold (P < 0.001), and aortic pressure was maintained (P < 0.01) in the Liquid group, in contrast to progressive hypoxemia, hypercarbia, and shock in the Gas group. Central venous pressure did not change. The Liquid-Hypoxia group was similar to the Gas group. We conclude that high-frequency partial liquid ventilation improves gas exchange and stabilizes pulmonary and systemic hemodynamics compared with high-frequency gas ventilation. The stabilization appears to be due in large part to improvement in gas exchange. 相似文献
110.
Mediators of septic shock: new approaches for interrupting the endogenous inflammatory cascade 总被引:1,自引:0,他引:1
BP Giroir 《Canadian Metallurgical Quarterly》1993,21(5):780-789
OBJECTIVES: To review the molecular pathogenesis of septic shock, with particular emphasis on the induction of cytokines by endotoxin. By understanding the mechanisms that result in the systemic inflammatory response, novel clinical interventions may be more effectively studied. DATA SOURCES: The English medical literature was reviewed, including human clinical trials, animal experiments, and in vitro studies elucidating cellular and molecular interactions. Expert testimony from the Roundtable Conference on Sepsis (Brussels, March 1992) was also used to synthesize emerging concepts and to ensure inclusion of ongoing investigations. STUDY SELECTION: Emphasis on controlled experimental studies which elucidated the molecular and cellular interactions during sepsis. DATA EXTRACTION: This study focused only on data that directly involved the induction and regulation of protein mediators of sepsis, especially tumor necrosis factor (TNF) and interleukin-1. Data concerning the role of TNF during health were extracted from the author's peer-reviewed data. DATA SYNTHESIS: Information concerning the many facets of the systemic inflammatory response was integrated into a chronological, clinically oriented model of cytokine induction during endotoxemia. CONCLUSIONS: The induction of inflammation during sepsis is a complex, but increasingly understood, biological cascade that is dependent on inter- and intracellular signaling. Novel biotherapies may improve patient outcome in sepsis by interrupting any or all points of signal transduction. 相似文献