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The predominant metabolic pathway of gemcabene in humans is glucuronidation. The principal human UDP-glucuronosyltransferases (UGTs) involved in the glucuronidation of gemcabene were determined in this study. Glucuronidation of gemcabene was catalyzed by recombinant UGT1A3, recombinant UGT2B7, and recombinant UGT2B17, as well as by human liver microsomes (HLM). Gemcabene glucuronidation in recombinant UGTs and HLM followed non-Michaelis-Menten kinetics consistent with homotropic activation, but pharmacokinetics in humans were linear over the dose range tested (total plasma C(max), 0.06-0.88 mM). Gemcabene showed similar affinity (S(50)) for recombinant UGTs (0.92-1.45 mM) and HLM (1.37 mM). S-Flurbiprofen was identified as a more selective inhibitor of recombinant UGT2B7-catalyzed gemcabene glucuronidation (>23-fold lower IC(50)) when compared with recombinant UGT1A3- or recombinant UGT2B17-catalyzed gemcabene glucuronidation. The IC(50) for S-flurbiprofen inhibition of gemcabene glucuronidation was similar in HLM (60.6 microM) compared with recombinant UGT2B7 (27.4 microM), consistent with a major role for UGT2B7 in gemcabene glucuronidation in HLM. In addition, 5,6,7,3',4',5'-hexamethoxyflavone inhibited recombinant UGT1A3 and recombinant UGT2B17-catalyzed gemcabene glucuronidation (with 4-fold greater potency for recombinant UGT1A3) but did not inhibit gemcabene glucuronidation in HLM, suggesting that UGT1A3 and UGT2B17 do not contribute significantly to gemcabene glucuronidation. Reaction rates for gemcabene glucuronidation from a human liver bank correlated well (r(2)=0.722, P<0.0001; n=24) with rates of glucuronidation of the UGT2B7 probe substrate 3'-azido-3'-deoxythymidine. In conclusion, using the three independent experimental approaches typically used for cytochrome P450 reaction phenotyping, UGT2B7 is the major enzyme contributing to gemcabene glucuronidation in human liver microsomes.  相似文献   
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OBJECTIVE: To evaluate both institutional and individual learning curves with focused abdominal ultrasound for trauma (FAST) by analyzing the incidence of diagnostic inaccuracies as a function of examiner experience for a group of trauma surgeons performing the study in the setting of an urban level I trauma center. SUMMARY BACKGROUND DATA: Trauma surgeons are routinely using FAST to evaluate patients with blunt trauma for hemoperitoneum. The volume of experience required for practicing trauma surgeons to be able to perform this examination with a reproducible level of accuracy has not been fully defined. METHODS: The authors reviewed prospectively gathered data for all patients undergoing FAST for blunt trauma during a 30-month period. All FAST interpretations were validated by at least one of four methods: computed tomography, diagnostic peritoneal lavage, celiotomy, or serial clinical evaluations. Cumulative sum (CUSUM) analysis was used to describe the learning curves for each individual surgeon at target accuracy rates of 85%, 90%, and 95% and for the institution as a whole at target examination accuracy rates of 85%, 90%, 95%, and 98%. RESULTS: Five trauma surgeons performed 546 FAST examinations during the study period. CUSUM analysis of the aggregate experience revealed that the examiners as a group exceeded 90% accuracy at the outset of clinical examination. The level of accuracy did not improve with either increased frequency of performance or total examination experience. The accuracy rates observed for each trauma surgeon ranged from 87% to 98%. The surgeon with the highest accuracy rate performed the fewest examinations. No practitioner demonstrated improved accuracy with increased experience. CONCLUSIONS: Trauma surgeons who are newly trained in the use of FAST can achieve an overall accuracy rate of at least 90% from the outset of clinical experience with this modality. Interexaminer variations in accuracy rates, which are observed above this level of performance, are probably related more to issues surrounding patient selection and inherent limitations of the examination in certain populations than to practitioner errors in the performance or interpretation of the study.  相似文献   
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Restorative proctocolectomy with J-pouch ileoanal anastomosis   总被引:6,自引:0,他引:6  
Restorative proctocolectomy with ileoanal anastomosis, complemented by a pouch formed with the last foot of terminal ileum, is the procedure of choice for patients in need of surgical treatment for ulcerative colitis and familial polyposis. The procedure has undergone many technical modifications that have ensured a very high degree of continence and an acceptable number of daily bowel movements. Herein we describe the operative technique we use in the majority of our patients, a restorative proctocolectomy with hand-sewn J-pouch ileoanal anastomosis with protecting ileostomy. We also comment on the immediate postoperative care and on the long-term functional results.  相似文献   
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ABSTRACT: BACKGROUND: Systemic therapeutics targeting the peroxisome proliferator-activated receptors have been found to be beneficial in the treatment of diabetic retinopathy. In this paper, we provide a rationale for the use of these therapeutics as intraocular agents. In addition, we introduce the peroxisome proliferator-activated receptors and describe their functions in response to the drugs. DISCUSSION: Based on the evidence of large-scale clinical studies investigating the systemic administration of fenofibrate, this ligand for peroxisome proliferator-activated receptor-alpha is potentially a good candidate for intraocular delivery. Here, we describe the mechanisms by which it might be acting to improve diabetic retinopathy, its relative safety and we speculate on how it could be developed for intraocular delivery. SUMMARY: In this paper, we provide a rationale for the further investigation of peroxisome proliferator-activated receptor-alpha agonists as intraocular agents for the treatment of diabetic retinopathy.  相似文献   
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Modern medical simulation technology (MST) debuted in 1960 with the development of Resusci Annie (Laerdal 2007), which assisted students in the acquisition of proper ventilation and compression techniques used during basic life support. Following a steady stream of subsequent technological advances and innovations, MST manufacturers are now able to offer training aids capable of facilitating innovative learning in such diverse areas as human patient simulators, simulated clinical environments, virtual procedure stations, virtual medical environments, electronic tutors, and performance recording. The authors list a number of the most popular MSTs presently available while citing evaluative efforts undertaken to date regarding the efficacy of MST to the medical profession. They conclude by proposing a variety of simulation innovations of prospective interest to both medical and technology personnel while offering healthcare administrators a series of recommended considerations when planning to integrate MST into existing medical systems.  相似文献   
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