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81.
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Increased circulating growth hormone (GH) levels and aberrant response to different stimuli characterize both type 1 diabetes mellitus and chronic uremia and are associated with severe retinal, kidney and heart complications. Combined kidney and pancreas transplantation is a therapy that restores the endogenous, closed-loop, insulin secretion in diabetes and cure uremia. To evaluate if combined transplantation can restore a normal secretion and response of GH to growth hormone releasing hormone (GH-RH), we studied four groups of subjects: (1) seven type 1 diabetic patients with end-stage renal failure who had received pancreas and kidney transplantation (KPTx); (2) six diabetic uremic subjects, candidates for combined transplantation (IDDUP); (3) nine patients with chronic uveitis on immunosuppressive therapy comparable to pancreas recipients, six of whom treated only with prednisone (UVEST), while three (4) were treated with both prednisone and cyclosporin (UVESTCY). All subjects underwent a GH-RH test (50 microg intravenously, i.v., at 13:00 h). Serum insulin levels were significantly higher in IDDUP compared to UVEST (P=0.05) both at baseline and post GH-RH stimulus, while were similar to KPTx (P=0.2) and UVESTCY (P=0.7). In contrast, plasma free fatty acids were similar in all groups. In IDDUP baseline plasma glycerol was higher than in KPTx (P=0.04) and UVEST (P=0.02) and similar to UVESTCY (P=0.36); glycerol concentration did not change after GH-RH (P=0.08). Before and after GH-RH, serum GH levels tended to be higher in IDDUP (P=0.5) and KPTx (P=0.2) compared to UVEST and UVESTCY. Our results indicate that: 1) kidney-pancreas transplantation does not normalize the GH response to GH-RH; 2) GH abnormalities are not due either to the chronic immunosuppressive therapy or to the insulin effect on GH release; 3) GH abnormalities are probably secondary to functional and/or organic complications of the hypothalamus and/or pituitary as a sequela of diabetes mellitus.  相似文献   
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PURPOSE: Imatinib (Glivec) is a potent inhibitor of bcr/abl, an oncogenic fusion protein that causes chronic myelogenous leukemia (CML). alpha1 acid glycoprotein (AGP) binds to imatinib with high affinity and inhibits imatinib activity in vitro and in vivo in an animal model. A pharmacokinetics analysis of imatinib was undertaken in CML patients. EXPERIMENTAL DESIGN: Imatinib plasma concentrations were measured in 19 CML patients treated with imatinib (400 or 600 mg/day). Five patients received a concomitant short-term course of clindamycin (CLI). RESULTS: A positive correlation between AGP and imatinib plasma levels was observed. CLI administration decreased imatinib plasma concentrations, evaluated as area under the curve (AUC) and peak concentrations (C(max)). The effects of a bolus of CLI was studied in three patients on imatinib 23 h after the last imatinib dose. Within 5-10 min in three of three cases, CLI caused a decrease in imatinib plasma concentrations of 2.6-, 2.7-, and 4.7-fold, respectively. In vitro experiments using fresh blasts from CML patients showed that AGP, at concentrations observed in the patients, decreased imatinib intracellular concentrations up to 10 times and blocked imatinib activity. The incubation with CLI restored imatinib intracellular concentrations and biological activity. CONCLUSION: AGP exerts significant effects of the pharmacokinetics, plasma concentrations, and intracellular distribution of imatinib in CML patients; these data indicate that plasma imatinib levels represent unreliable indicators of the cellular concentrations of this molecule.  相似文献   
85.
In vitro exposure to ecstasy (3,4-methylenedioxymethamphetamine, MDMA) alters some immune parameters such as T-cell regulatory function, cytotoxic T-lymphocyte activity, natural killer cell activity and macrophage function. Administration of MDMA in rats produces a suppression of lympho-proliferation response and a decrease in circulating lymphocytes, accompanied by an increase in plasma corticosterone. It was postulated a direct action of MDMA on lymphocytes or rather an indirect action mediated by the hypothalamic pituitary adrenal axis (HPA-AXIS) and/or the sympathetic nervous system (SNS). Acute MDMA treatment effected on healthy-volunteers produces an immune dysfunction associated with pharmaceutical characteristics and so with MDMA plasma concentrations. There is a decrease in CD4+ T-cells and functional responsiveness of lymphocytes, while percentage of natural killer cells increases. A contemporary rise of cortisol plasma concentrations supports the hypothesis of MDMA-induced release of corticotrophin-releasing factor from the hypothalamus and subsequent HPA-axis and SNS activation.  相似文献   
86.
In order to evaluate the risk connected with hand-arm vibration exposure and associated disorders of the peripheral nervous system a study was made to assess the relationship between nervous symptoms and laboratory data to determine the kind of disorder. 40 male subjects with hand-arm vibration exposure for more than 5 years and nervous symptoms of the hands for more than 1 year and 2 control groups of non-symptomatic non-exposed subjects were considered. An electroneurophysiological study of the exposed subjects revealed 18 nerve conduction speed changes (12 median nerve, 4 ulnar nerve, 2 median and ulnar nerve), most of which were sensitivity-motor changes; only 9 Carpal Tunnel Syndromes were diagnosed. Some statistically significant differences between exposed subjects with negative results of the electroneurophysiological study and non-exposed subjects were observed. Prolonged vibration exposure seems to induce a hand-arm nerve suffering, initially with a progressive nerve conduction speed change and non-specific symptoms, but subsequently a peripheral nervous system disorder associated or not to a Carpal Tunnel Syndrome may occur.  相似文献   
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PURPOSE: A drug utilization trial was performed to investigate acute versus short-term effects after switching or adding bimatoprost in open-angle glaucoma patients over a 3- month observation period. METHODS: One (1) eye was randomly chosen from 47 glaucomatous patients (abnormal visual field and/or abnormal optic nerve and intraocular pressure (IOP) above 21 mmHg without treatment). Only patients who did not reach the target IOP with their ongoing treatment were recruited in this study. IOP was measured at baseline, after 1 hour, and 2 hours from the first instillation and after 1 week, 1, and 3 months of treatment. RESULTS: The IOP before bimatoprost administration was 20.16+/-3.6 mmHg (mean+/-standard deviation). There was no statistically significant decrease of IOP after 1 hour (mean IOP, 19.96+/-4.25 mmHg) and after 2 hours (mean IOP, 17.73+/-3.24 mmHg). Statistically significant (p<0.001) decreases after 1 week (mean IOP, 16.48+/-2.9 mmHg), after 1 month (mean IOP, 16.48+/-2.9 mmHg) and after 3 months (mean IOP, 16.15+/-2.7 mmHg) were found. CONCLUSION: The results suggested that bimatroprost had a significant acute effect on IOP in monotherapy, while no significant effect was found when the therapy was switched or added. The effect for primary open-angle glaucoma was very evident. There was no specific side effect attributable to combining bimatoprost with any of the treatments in use.  相似文献   
89.
BACKGROUND: A review of the experience with laparoscopic cholecystectomy to evaluate the impact of the efficacy, safety, and complications on the learning curve. Study design: Retrospective study. METHODS: Between 1993 and 1998, 415 patients, 123 males and 292 females, median age 52.1 years (range 23-96 years), with symptomatic cholelithiasis, underwent laparoscopic cholecystectomy. On the basis of different selection criteria and surgical techniques adopted, our experience was divided into two periods (93-95 and 96-98). RESULTS: The success rate was 89.4% (371 patients) with a conversion rate of 10.6% (44 patients). Overall complications rate was 2.9% (12 patients): 7 major complications (2 biliary tract injuries, 2 hemorrhages, 1 sub-phrenic abscess, 1 gastric perforation and 1 choleperitoneum) and 3 minor complications (1 biliary leakage and 2 wound infections) with 2 long-term sequela (umbilical site eventration). Median hospital stay was 3.3 days, 2.2 days for uncomplicated cases and 5.6 in those converted or complicated. Comparison between the two groups showed a conversion rate of 10.6 vs 10.4% (23 vs 21 patients), with a complication rate of 4.2% vs 2.2%. CONCLUSIONS: Laparoscopic cholecystectomy can be considered a safe and effective procedure for the treatment of simple or complicated cholelithiasis. French surgical technique seems to be easier in the management of acute cholecystitis or lithiasis occurring after acute pancreatitis. Specific training in laparoscopy surgery is mandatory to avoid major complications.  相似文献   
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