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Septic or inflammatory stimuli suppress drug metabolism by cytochrome P-450 in the liver, presumably at the pretranslational level. We have shown previously that nitric oxide is responsible at least in part for the inhibition by bacterial lipopolysaccharide of phenobarbital-induced CYP2B1/2 activity in vivo. This was attributed to the interaction of nitric oxide with heme in the active-center of cytochrome P450, leading to enzyme inactivation. Here, we report of nitric oxide with heme in the active-center of cytochrome P450, leading to enzyme inactivation. Here, we report that endogeneous nitric oxide also contributes to LPS-induced suppression of CYP2B1/2 in vivo by down-regulating the expression of CYP2B1/2 protein and mRNA. 相似文献
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Thuy T. Chau Thomas Walter Alan Katz Barry M. Weichman 《Drug development research》1993,28(4):488-495
Pemedolac Na, 1-ethyl-1,3,4,9-tetrahydro-4-(phenylmethyl)-pyrano [3,4-b] indole-1-acetic acid sodium salt, exhibited equipotent analgesic effects after oral, iv, and im administration, suggesting that it is well absorbed. In mouse writhing models, the ED50 values ranged from 0.3 mg (0.81 μmol)/kg (vs. acetylcholine) to 4.3 mg (11.6 μmol)/kg (vs. paraphenylbenzoquinone [PBQ]). In the rat Randall-Selitto model, the ED50 o the compound was approximately 0.001 mg (2.7 nmol)/kg, with a flat dose response curve. The peak effects lasted for 7–9 h, 10–18 h, and 5 h following oral, im, and iv injections, respectively. Intracerebroventricular (i.c.v.) injections of pemedolac Na inhibited the PBQ-induced writing in mice with an ED50 of 43.5 μg (0.12 μmol)/mouse, and this effect was not antagonized by naloxone. It was inactive in the hot plate and tail flick tests, demonstrating that pemedolac Na does not act via an opiate mechanism. These results indicate that pemedolac Na is a viable parenteral and oral analgesic, typified by high analgesic potency, a rapid onset and long duration of action, and an extremely wide safety index. © Wiley-Liss, Inc. 相似文献
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Volker Heinemann 《Breast cancer research and treatment》2003,81(1):43-48
Single-agent chemotherapy of metastatic breast cancer is the treatment of choice in patients with slow tumor progression and asymptomatic disease. In this patient group, the choice of drugs is based more on good tolerability than on efficacy. By contrast, symptomatic or rapidly progressing disease requires the use of highly active regimens where more weight is put on reliable antitumor activity. While anthraycline-based combination regimens have set the standard of effective treatment, the addition of docetaxel (and to a lesser extent paclitaxel) has improved tumor response, but failed to induce a consistent prolongation of survival. Based on retrospective analyses, it is hypothesised that the combined use of anthracyclines and taxanes in first-line therapy may be most beneficial in defined subgroups: after adjuvant chemotherapy, in patients with HER-2 gene amplification, possibly also in patients with rapidly progressing visceral disease. 相似文献
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Antegrade interlocking nailing of humeral shaft fractures 总被引:5,自引:0,他引:5
George Petsatodes Dimitrios Karataglis Pericles Papadopoulos John Christoforides John Gigis John Pournaras 《Journal of orthopaedic science》2004,9(3):247-252
The results of 39 humeral shaft fractures (37 patients) treated with antegrade locked nailing using a Russell–Taylor nail were reviewed. There were 30 acute fractures, 6 fractures malaligned in a hanging cast or brace, and 3 pathological fractures. Patient age ranged from 26 to 80 years (average, 59.7 years) and average follow-up was 25.7 months (range, 6–48 months). Fracture union was achieved in 92.3% of our cases, while shoulder function was excellent or good in 87.2% of cases. Antegrade locked nailing offers a dependable solution for the treatment of humeral shaft fractures, especially in polytrauma patients and cases of segmental or pathological fractures. Far less satisfactory results were obtained in comminuted fractures of the proximal third in the humerus, especially in osteoporotic patients, and we therefore advocate caution with the use of intramedullary nailing in this type of fracture. Certain technical aspects such as avoiding nailing the fracture in distraction, properly countersinking the tip of the nail, and achieving adequate fixation stability have been found to be of paramount importance to reduce the incidence of delayed union/non-union rate and to obtain better functional results from the shoulder joint. 相似文献
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