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991.
This study is an evaluation of short- and long-term benefits of total parenteral nutrition (TPN) in 20 patients with active Crohn's disease but without fistulae. TPN was done during 42 (14-80) days (median-range) after failure of medical therapy including patients with steroid-resistant (11 SR) or steroid-dependent (9 SD) active Crohn's disease. Efficacy of short-term TPN was demonstrated by nutritional repair and achievement of clinical remission in all but one patients. Follow-up was 28 (8-78) months in the 19 patients (10 SR, 9 SD) discharged improved after the end of TPN. At 1 yr, the cumulative recurrence rate was 26% (5/19). During the follow-up, three patients (2 SR, 1 SD) remained symptom-free, 13 (6 SR, 7 SD) had a partial remission defined as relapse controlled by medication, and only three patients (2 SR, 1 SD) had a relapse uncontrolled by medical therapy leading to surgery. Therefore in our selected population without fistula or abscess, after failure of medical therapy TPN was obviously an effective therapy which avoided surgery. Furthermore follow-up indicated that SD and SR were only transient events in the course of Crohn's disease patients.  相似文献   
992.
One hundred and sixty-three patients treated with electroconvulsive therapy (ECT) in a district psychogeriatric unit during 1981 were followed up after 3 years. After the original course (mean 11·2 treatments) 51% were rated as fully recovered and 23% as much improved. Two-thirds experienced one or more relapse within 3 years but half of these regained full remission. Of the 113 patients alive at 3 years 59% were free of depression and 29% showed mild symptoms only. Those making full initial recoveries had fared best subsequently. It is suggested that ECT has an important and generally underestimated place in the management of depression in the elderly.  相似文献   
993.
994.
The effect of gemfibrozil on the pharmacokinetics of rosuvastatin   总被引:13,自引:0,他引:13  
BACKGROUND: Coadministration of statins and gemfibrozil is associated with an increased risk for myopathy, which may be due in part to a pharmacokinetic interaction. Therefore the effect of gemfibrozil on rosuvastatin pharmacokinetics was assessed in healthy volunteers. Rosuvastatin has been shown to be a substrate for the human hepatic uptake transporter organic anion transporter 2 (OATP2). Inhibition of this transporter could increase plasma concentrations of rosuvastatin. The effect of gemfibrozil on rosuvastatin uptake by cells expressing OATP2 was also examined. METHODS: In a randomized, double-blind, 2-period crossover trial, 20 healthy volunteers were given oral doses of gemfibrozil, 600 mg, or placebo twice daily for 7 days. On the fourth morning of each dosing period, a single oral dose of rosuvastatin, 80 mg, was coadministered. Plasma concentrations of rosuvastatin, N-desmethyl rosuvastatin, and rosuvastatin-lactone were measured. In addition, the effect of gemfibrozil on the uptake of radiolabeled rosuvastatin by OATP2-transfected Xenopus oocytes was studied. RESULTS: Gemfibrozil increased the rosuvastatin area under the plasma concentration-time curve from time 0 to the time of the last quantifiable concentration [AUC(0-t)] 1.88-fold (90% confidence interval, 1.60-2.21) and the maximum observed rosuvastatin plasma concentration (C(max)) 2.21-fold (90% confidence interval, 1.81-2.69) compared with placebo. N-desmethyl rosuvastatin AUC(0-t) and C(max) decreased by 48% and 39%, respectively. Pharmacokinetics of rosuvastatin-lactone was unchanged. The in vitro results indicate that the maximum gemfibrozil inhibition of rosuvastatin OATP2-mediated uptake was 50%; the inhibition constant for the inhibitory process was 4.0 +/- 1.3 micromol/L. CONCLUSIONS: Gemfibrozil increased rosuvastatin plasma concentrations approximately 2-fold, which is similar to the effect of gemfibrozil on pravastatin, simvastatin acid, and lovastatin acid plasma concentrations and substantially less than the effect observed for cerivastatin. Gemfibrozil inhibition of OATP2-mediated rosuvastatin hepatic uptake may contribute to the mechanism of the drug-drug interaction. Care is warranted when gemfibrozil is coadministered with rosuvastatin and other statins.  相似文献   
995.
Expression of drug-resistant forms of dihydrofolate reductase (DHFR) in hematopoietic cells confers substantial resistance of animals to antifolate administration. In this study, we tested whether the chemoprotection conferred by expression of the tyrosine-22 variant DHFR could be used for more effective therapy of the 32Dp210 murine model of chronic myeloid leukemia (CML). 32Dp210 tumor cells were found to be sensitive to methotrexate (MTX) in vitro, whereas cells expressing the tyrosine-22 DHFR gene were protected from MTX at up to micromolar concentrations. MTX administered at low dose (2 mg/kg/day) did not protect normal C3H-He/J mice from 32Dp210 tumor infused intravenously, with drug toxicity limiting the administration of higher doses. Animals engrafted with transgenic tyrosine-22 DHFR marrow were protected from greater MTX doses (up to 6 mg/kg/day). However, the increased doses of MTX afforded by drug-resistance gene expression surprisingly resulted in decreased survival of the transplanted tumor-bearing animals, with increased levels of tumor detected in peripheral blood. This apparent exacerbation of tumor progression by MTX was not observed in DHFR transgenic mice in which all cells and tissues contain the drug-resistance gene. This suggests that increased tumor progression in MTX-administered animals resulted from MTX sensitivity of a nonhematopoietic host component, thus allowing tumor expansion. We conclude that MTX exacerbates tumor progression in the 32Dp210 model of CML, and that based on this model alternate DHFR inhibitors combined with drug-resistant DHFR or other chemotherapeutic agent/drug-resistance gene combinations may be required for the application of drug-resistance gene expression to the treatment of CML.  相似文献   
996.
OBJECTIVE: To test the hypothesis that elevated concentrations of interleukin-8 associated with anti-interleukin-8 autoantibodies (anti-interleukin-8:interleukin-8 complexes) are found in patients at risk for acute respiratory distress syndrome who developed the disease. DESIGN: Measurement of anti-interleukin-8:interleukin-8 complex concentrations in previously collected bronchoalveolar lavage fluids. These fluids were obtained from patients at risk for acute respiratory distress syndrome who subsequently either recovered or developed acute respiratory distress syndrome. PATIENTS: A unique population of patients at risk for acute respiratory distress syndrome was studied. There were 26 patients at risk for acute respiratory distress syndrome who were divided into three groups. Group I patients had high interleukin-8 concentrations and developed acute respiratory distress syndrome, group II had high interleukin-8 concentrations and did not develop acute respiratory distress syndrome, and group III had low interleukin-8 concentrations and did not develop acute respiratory distress syndrome. These patients were selected to test the hypothesis that presence of elevated concentrations of anti-interleukin-8:interleukin-8 complexes differentiates patients at risk for acute respiratory distress syndrome who developed acute respiratory distress syndrome from patients who did not. MEASUREMENTS AND MAIN RESULTS: Bronchoalveolar lavage fluid concentrations of interleukin-8 associated with the anti-interleukin-8 autoantibodies were significantly different between groups (p <.03). The amount of interleukin-8 bound to the anti-interleukin-8 autoantibody was higher in group I than in group II and group III. CONCLUSIONS: Bronchoalveolar lavage fluid concentration of anti-interleukin-8:interleukin-8 complexes may serve as a marker of disease progression in patients at risk for acute respiratory distress syndrome.  相似文献   
997.
Cell surface proteins major histocompatibility complex (MHC) class I-related chain A (MICA) and UL16-binding proteins (ULBP) 1, 2, and 3 are up-regulated upon infection or tumor transformation and can activate human natural killer (NK) cells. Patches of cross-linked raft resident ganglioside GM1 colocalized with ULBP1, 2, 3, or MICA, but not CD45. Thus, ULBPs and MICA are expressed in lipid rafts at the cell surface. Western blotting revealed that glycosylphosphatidylinositol (GPI)-anchored ULBP3 but not transmembrane MICA, MHC class I protein, or transferrin receptor, accumulated in detergent-resistant membranes containing GM1. Thus, MICA may have a weaker association with lipid rafts than ULBP3, yet both proteins accumulate at an activating human NK cell immune synapse. Target cell lipid rafts marked by green fluorescent protein-tagged GPI also accumulate with ULBP3 at some synapses. Electron microscopy reveals constitutive clusters of ULBP at the cell surface. Regarding a specific molecular basis for the organization of these proteins, ULBP1, 2, and 3 and MICA are lipid modified. ULBP1, 2, and 3 are GPI anchored, and we demonstrate here that MICA is S-acylated. Finally, expression of a truncated form of MICA that lacks the putative site for S-acylation and the cytoplasmic tail can be expressed at the cell surface, but is unable to activate NK cells.  相似文献   
998.
We have previously reported that modest dietary sodium restriction, as advocated in management guidelines for diabetes, may reduce insulin sensitivity. It has since been suggested that this effect may be mediated via cross-talk between insulin and angiotensin II (AII)-stimulated intracellular second messengers. In order to assess the effect of 5 days of modest sodium restriction (to <80 mmol/day target sodium intake) on insulin sensitivity, 15 healthy males underwent a double-blind, placebo-controlled, randomized, cross-over euglycaemic hyperinsulinaemic clamp study. One phase was supplemented with sodium tablets and the other with matched placebo. Insulin sensitivity (M) was reduced during dietary sodium restriction [median M value, 10.2 mg/kg per min (interquartile range 9.50-13.85) versus 12.8 mg/kg per min (interquartile range 9.60-14.30), P <0.05]. To elucidate potential mechanisms that may explain this observation, we investigated the effect of AII on insulin action in isolated adipocytes obtained from healthy females. No effect of AII on insulin-mediated glucose transport or suppression of lipolysis was observed. In conclusion, despite the observation that dietary sodium restriction was associated with a median 15% reduction in insulin sensitivity, we found no evidence of a direct effect of AII on insulin action in human adipocytes.  相似文献   
999.
1000.

Purpose

Topical therapy (TT) for upper tract urothelial carcinoma (UTUC) has been explored as a kidney sparing approach to treat carcinoma in situ (CIS) and as adjuvant for endoscopically treated Ta/T1 tumors. In bladder cancer, data support use of salvage TT for repeat induction. We investigate the outcomes of salvage TT for UTUC in patients ineligible for or refusing nephroureterectomy.

Methods

A single-center retrospective review on patients receiving salvage TT via percutaneous nephrostomy tube or cystoscopically placed ureteral catheters was performed. Primary outcome was response to therapy based on International Bladder Cancer Group criteria.

Results

51 patients with 58 renal units (RUs) received TT. Of these, 17 patients with 18 RUs received the second-line TT, with a median follow-up of 36.5 months (IQR 24.5–67 months). 44% (8/18) received salvage TT for refractory disease and 56% (10/18) as reinduction. 5 RUs with CIS were unresponsive to initial TT and went on to receive salvage TT, of which 20% (1/5) responded. 13 RUs recurred or relapsed following initial TT and received salvage TT for papillary tumors, with 62% (8/13) responding.

Conclusion

Our data provide preliminary clinical rationale for the second-line TT for refractory and recurrent, endoscopically managed papillary UTUC in patients ineligible for or refusing nephroureterectomy. However, refractory upper tract CIS appears to have poor response to salvage TT.
  相似文献   
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