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1. Mean concentrations of total 14 C and of dexloxiglumide at the end of single 20-min infusion doses of 14 C-dexloxiglumide (200?mg) to four healthy male subjects were 18.5 µ?g eq. ml ? 1 and 19.5 µ?g ml ? 1, respectively. The mean plasma clearance (0.22 l?h ? 1 kg ? 1) and mean volume of distribution (V ss = 0.18?l kg ? 1) were low. 2. Single oral doses of a solid formulation of 14 C-dexloxiglumide (200?mg) to the same subjects appeared to be rapidly and well absorbed. Mean peak plasma concentrations (C max) of total 14 C (2.8 µ?g eq. ml ? 1) and of dexloxiglumide (2.2 µ?g ml ? 1) occurred at about 1.5?h. Systemic availabilities of the oral dose based on total 14 C and dexloxiglumide were 70 and 48%, respectively. Thus, a proportion of an oral dose was subjected to presystemic elimination and the absorbed dose mainly eliminated by metabolism. Binding of dexloxiglumide to plasma proteins was extensive (96.6-99.2%). 3. Total 14 C was excreted mainly in the faeces. Mass balance of 14 C excretion was almost complete within 7 days when a mean of > 93% of the dose had been recovered. After the intravenous (i.v.) dose, mean totals of 23.7 and 69.8% of the dose were excreted in urine and faeces, respectively, during 7 days, and 19.5 and 73.7% of the dose, respectively, after the oral dose. The data were consistent with biliary excretion and perhaps some enterohepatic circulation of conjugates of dexloxiglumide and at least one of its metabolites. 4. LC-MS/MS of urine extracts showed that dexloxiglumide was metabolized by oxidation and conjugation. The former included at least two metabolites formed by monohydroxylation in the N- (3-methoxypropyl) pentyl side chain, and O-demethylation of this side chain followed by subsequent oxidation of the resultant alcohol to the dicarboxylic acid. At least one glucuronide was also present in urine. The main components in faeces appeared to be dexloxiglumide and a dicarboxylic metabolite formed by O-demethylation followed by oxidation of the N- (3-methoxypropyl) side chain. Both compounds were identified as their corresponding methyl esters formed because acid and methanol were used in the extraction procedure. Dexloxiglumide and the dicarboxylic acid were presumably excreted in bile as the glucuronic acid conjugates.  相似文献   
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OBJECTIVES: Some patients and oncologists choose to treat localized esophageal cancer with definitive chemotherapy and radiation therapy rather than surgery. A subset of these patients have local relapse without distant metastases and therefore have no other curative intent treatment option but salvage esophagectomy. METHODS: We reviewed our experience with salvage esophagectomy from 1987 to 2000 at M.D. Anderson Cancer Center (n = 13, salvage after chemotherapy and radiotherapy group) and compared the data with those of patients receiving esophagectomy in a planned fashion 4 to 6 weeks after preoperative chemotherapy and radiation therapy (n = 99, preoperative chemotherapy and radiotherapy group). RESULTS: Increases in morbidity were seen after resection in the salvage after chemotherapy and radiotherapy group relative to the preoperative chemotherapy and radiotherapy group: mechanical ventilation (9.0 days vs 3.3 days, P =.08), intensive care unit stay (11.2 days vs 5.1 days, P =.07), hospital stay (29.4 days vs 18.4 days, P =.03), and anastomotic leak rates (5/13 [39%] vs 7/99 [7%], P =.005). Operative mortality (within 30 days) also tended to be increased statistically nonsignificantly (2/13 [15%] vs 6/99 [6%], P =.2). Salvage esophagectomy resulted in long-term survival (25% 5-year survival) in a subset of patients. Improved survival after salvage esophagectomy was associated with early pathologic stage (T1 N0, T2 N0), prolonged time to relapse, and R0 surgical resection. CONCLUSION: Patients who undergo salvage esophagectomy for relapse of tumor after definitive chemoradiation therapy have increased morbidity, mortality, and hospital use relative to patients undergoing planned esophagectomy after preoperative chemoradiation. Nevertheless, long-term survival can be achieved in this group, and such treatment should be considered for carefully selected patients at an experienced center.  相似文献   
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Summary  

During and after prolonged bed rest, changes in bone metabolic markers occur within 3 days. Resistive vibration exercise during bed rest impedes bone loss and restricts increases in bone resorption markers whilst increasing bone formation.  相似文献   
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A biomechanical study comparing simulated lytic vertebral metastases treated with laser-induced thermotherapy (LITT) and vertebroplasty versus vertebroplasty alone. To investigate the effect of tumor ablation using LITT prior to vertebroplasty on biomechanical stability and cement fill patterns in a standardized model of spinal metastatic disease. Vertebroplasty in the metastatic spine is aimed at reducing pain, but is associated with risk of cement extravasation in up to 10%. Six pairs of fresh-frozen cadaveric thoracolumbar spinal motion segments were tested in axial compression intact, with simulated metastases and following percutaneous vertebroplasty with or without LITT. Canal narrowing under load, pattern of cement fill, load to failure, and LITT temperature and pressure generation were collected. In all LITT specimens, cement filled the defect without extravasation. The canal extravasation rate was 33% in specimens treated without LITT. LITT and vertebroplasty yielded a trend toward improved posterior wall stability (P = 0.095) as compared to vertebroplasty alone. Moderate rises in temperature and minimal pressure generation was seen during LITT. In this model, elimination of tumor by LITT, facilitates cement fill, enhances biomechanical stability and reduces the risk of cement extravasation.  相似文献   
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The open components separation technique (CST) for hernia repair allows for autologous tissue repair with approximation of the midline fascia in patients with complex hernias. CST requires creation of large undermining skin flaps, whereas the endoscopic component separation technique (ECST) is performed without division of the epigastric perforating vessels and may minimize wound morbidity. A review of patient demographics and outcome measures of patients undergoing CST and ECST between November 2008 and February 2010 was performed. Twenty-five patients were identified who underwent either CST (14 patients) or ECST (11 patients). There were no differences in body mass index (CST 34.8 kg/m(2), ECST 37.5 kg/m(2), P = 0.45), operating room times (CST 268 minutes, ECST 252 minutes, P = 0.54), or hospital length of stay (CST 5 days, ECST 5.8 days, P = 0.78). Wound complications occurred less with ECST (9 vs 57%, P = 0.03). The time to resolution of wound complications in ECST was reduced *1 vs 4 months). No recurrences were seen in either group with a mean follow-up of 4months (range, 1 to 12 months). ECST and CST require similar operative times and hospital lengths of stay. ECST is associated with reduced wound complications compared with CST. Short-term recurrence rates with CST and ECST are comparable.  相似文献   
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BACKGROUND: It was of interest to compare enteric-coated mycophenolate sodium (EC-MPS) versus mycophenolate mofetil (MMF) among renal transplant recipients receiving a tacrolimus-based immunosuppressive regimen. METHODS: Between December 2004 and February 2006, a single-center, open-label randomized trial of MMF (group A, n=75) versus EC-MPS (group B, n=75) was performed in primary renal transplant recipients receiving combined thymoglobulin/daclizumab induction along with reduced tacrolimus dosing and elimination of corticosteroids 1 week postoperatively. The primary endpoint was the incidence rate of acute rejection (AR) during the first 12 months posttransplant; secondary aims were to compare graft and patient survival, renal function, drug dosing and monitoring, gastrointestinal side effects, and other adverse events at 12 months of follow-up. RESULTS: Patient/graft survival in groups A and B were 100%/96% versus 99%/96%, respectively (N.S.). At 12 months, a total of nine patients (6%) experienced biopsy-proven AR, 3% (2/75) vs. 9% (7/75) in the MMF and EC-MPS arms, respectively (N.S.). At 12 months, the geometric mean*/SE serum creatinine concentration and arithmetic mean+/-SE calculated glomerular filtration rate in groups A and B, respectively, were 1.30*/1.03 and 61.4+/-2.0 vs. 1.26*/1.03 and 66.0+/-2.1 (N.S.). Incidence of new onset diabetes mellitus (11% vs. 11%), infections requiring hospitalization (13% vs. 15%), and gastrointestinal side effects (36% vs. 32%) appeared equivalent (N.S.). CONCLUSIONS: Early efficacy and toxicity were equivalent between the two study arms. Optimizing either MMF or EC-MPS along with a combined thymoglobulin/daclizumab induction, low tacrolimus dosing and steroid avoidance resulted in a low AR rate and an acceptably high renal function at 12 months.  相似文献   
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