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31.
We investigated whether exposure to noise, in addition to its well-known potentiating effect on toluene-induced ototoxicity, may also exacerbate behavioral disturbances and brain neurochemical alterations produced by subchronic exposure to low toluene concentration. To test this hypothesis, we evaluated whether subchronic combined exposure (16 weeks, 104 h per week) to noise at 80 dB-A and toluene at 40 ppm potentiates the recently reported neurotoxic effects of subchronic exposure to 40 ppm toluene. Locomotor and rearing activities, sensitization to narcosis induced by acute toluene at high concentration, and tyrosine and tryptophan hydroxylase activities in the caudate-putamen and hippocampus were investigated in both male and female rats. Our results confirm that subchronic exposure to 40 ppm toluene significantly decreases rearing activity and leads to a sensitization to toluene-induced narcosis, as evaluated by loss of righting reflex, but fails to demonstrate any adverse effect of noise, alone or in combination with toluene. Given that toluene has addictive properties, the lack of potentiating behavioral and neurochemical effect of noise is discussed with regards to a recent study that has shown that methamphetamine neurotoxicity is potentiated by exposure to loud noise.  相似文献   
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The aim of imaging the brain in Multiple Sclerosis (MS) is to prove the dissemination of lesions, so critical for the diagnosis and so difficult to ascertain clinically. Our study included 21 patients with clinically definite (12) and probable (9) MS. A 21 patients underwent a neurological standard examination, a double-dose delayed CT scan and a Magnetic Resonance Imaging with a superconducting 0.5 Tesla magnet. Jointed slices were performed with a T2-weighted Spin-Echo sequence (TE 60, 120; TR 2000 msec). MRI detected 640 lesions in 20 patients while CT scan detected only 24 lesions in 9 patients. Technical limiting factors are discussed. Abnormalities in MRI were high-intense spots, blotches and streaks, located predominantly in the periventricular area. Capping lesions were common around the ventricular horns. "Plaques" were visualized in the posterior fossa. For each patient, the total surface of the lesions was calculated and was found to be related with the presence of lesions and with the cortical atrophy on CT scan. A correlation between the surface of lesions calculated by MRI and the disability scale was found especially in the group of patients with clinically proven cerebral lesions, while patients with predominantly spinal forms had a significantly lower surface of lesions. This finding could yield a new quantitative evaluation of the MS pathologic process which could be used to assess therapeutic efficacy.  相似文献   
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Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
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BackgroundEndoscopy plays a pivotal role in the management of adverse events (AE) following bariatric surgery. Leaks, fistulae, and post-operative collection after sleeve gastrectomy (SG) may occur in up to 10% of cases.ObjectivesTo evaluate the efficacy and safety of endoscopic internal drainage (EID) for the management of leak, fistula, and collection following SG.SettingRetrospective, observational, single center study on patients referred from several bariatric surgery departments to an endoscopic referral center.MethodsEID was used as first-line treatment for the management of leaks, fistulae, and collections. Leaks and fistulae were treated with double pigtail stent (DPS) deployment in order to guarantee internal drainage and second intention cavity obliteration. Collections were treated with endoscropic ultrasound (EUS)–guided deployment of DPS or lumen apposing metal stents.ResultsA total of 617 patients (83.3% female; mean age, 43.1 yr) were enrolled in the study for leak (n = 300, 48.6%), fistula (n = 285, 46.2%), and collection (n = 32, 5.2%). Median follow-up was 19.5 months. Overall clinical success was 84.7% whereas 15.3% of cases required revisional surgery after EID failure. Clinical success according to type of AE was 89.5%, 78.5%, and 90% for leak, fistula, and collection, respectively. A total of 10 of 547 (1.8%) presented a recurrence during follow-up. A total of 28 (4.5%) AE related to the endoscopic treatment occurred. At univariate logistic regression predictors of failure were: fistula (OR 2.012), combined endoscopic approach (OR 2.319), need for emergency surgery (OR 1.755), and previous endoscopic treatment (OR 4.818).ConclusionEarly EID for the management of leak, fistula, and post-operative collection after SG seems a safe and effective first-line approach with good long-term results.  相似文献   
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Because the dopamine reuptake inhibitors cocaine and BTCP produce different behavioral effects after repeated administration, we studied whether they could alter each other’s effects by examining the effects of crossing over repeated treatment with cocaine and BTCP on cocaine-induced locomotion. Male C57BL/6 mice were treated repeatedly with cocaine or BTCP during a first phase (days 1–3) and 3 days later, treated repeatedly with the same or the other compound during a second phase (days 7–9), after which they were administered one of several doses of cocaine on the next day. Locomotor activity was assessed after every daily treatment. The results show that 1) cocaine induced sensitization to its locomotor effects, 2) cocaine-induced sensitization was not altered by subsequent repeated treatment with BTCP, 3) initial repeated treatment with BTCP induced apparent cross-tolerance to cocaine, and 4) the initial effects of repeated BTCP were not markedly altered by subsequent repeated treatment with cocaine. The results indicate that the initial effects produced by repeated cocaine or BTCP are enduring and relatively difficult to alter by crossing over repeated treatment with the other compound. Thus, sensitization to the locomotor effects of cocaine in mice appeared to be attenuated by prior repeated treatment with BTCP but not reversed when followed by repeated treatment with BTCP. Received: 11 January 1998/Final version: 17 September 1998  相似文献   
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Vinflunine (VFL) is a novel derivative of vinorelbine (NVB, Navelbine®), which has shown markedly superior antitumor activity to NVB, in various experimental animal models. To establish whether this new Vinca alkaloid participates in P-glycoprotein (Pgp)-mediated multidrug resistance (MDR), VFL-resistant murine P388 cells (P388/VFL) were established in vivo and used in conjunction with the well established MDR P388/ADR subline, to define the in vivo resistance profile for VFL. P388/VFL cells proved cross-resistant to drugs implicated in MDR (other Vinca alkaloids, doxorubicin, etoposide), but not to campothecin or cisplatin and showed an increased expression of Pgp, without any detectable alterations in topoisomerase II or in glutathione metabolism. The P388/ADR cells proved cross-resistant to VFL both in vivo and in vitro, and this VFL resistance was efficiently modulated by verapamil in vitro. Cellular transport experiments with tritiated-VFL revealed differential uptake by P388 sensitive and P388/ADR resistant cells, comparable with data obtained using tritiated-NVB. In various in vitro models of human MDR tumor cells, whilst full sensitivity was retained in cells expressing alternative non-Pgp-mediated MDR mechanisms, cross resistance was identified in Pgp-overexpressing cells. Differences were, however, noted in terms of the drug resistance profiles relative to the other Vincas, with tumor cell lines proving generally least cross-resistant to VFL. Overall, these results suggest that VFL, like other Vinca alkaloids, participates in Pgp-mediated MDR, with tumor cells selected for resistance to VFL overexpressing Pgp, yet MDR tumor cell lines proved generally less cross resistant to VFL relative to the other Vinca alkaloids.  相似文献   
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OBJECTIVE: An adult trial reported the efficacy of recombinant human erythropoietin in critically ill patients with a 19% decrease in red blood cell transfusion. Our aim was to evaluate the relevance of this prophylactic treatment in children hospitalized in a pediatric intensive care unit (PICU). DESIGN: Cohort study from January 1995 to December 2004. SETTING: University hospital PICU. PATIENTS: Children between 1 month and 18 yrs of age. INTERVENTIONS: We searched through a prospective databank for all children hospitalized in the PICU for > or =4 days (potential recipients of erythropoietin, as proposed in the adult trial) and transfused with red blood cells after day 7 following PICU entry (in whom erythropoietin might prevent anemia, according to results of the adult trial). MEASUREMENTS AND MAIN RESULTS: We found that 799 of 2,578 children (31%) were hospitalized for > or =4 days. The study group comprised 787 patients who were hospitalized for > or =4 days in the PICU and for whom full records were available. One hundred eighty-three children in this study group were transfused during their stay in the PICU (median age, 7 months; weight, 6.60 kg). Hemoglobin levels before transfusion (mean +/- sd) were 7.7 +/- 1.5 g/dL. These transfused children represented 23% of the study group and 7% of the total PICU admissions. Forty-seven children (6% of the study group, 2% of the total PICU admissions) were transfused with red blood cells after 7 days of hospitalization and could have benefited from a prophylactic treatment with erythropoietin. Relative risk to benefit of a prophylactic treatment by erythropoietin was higher in cases of mechanical ventilation (relative risk, 1.18) and inotropic treatment (relative risk, 1.72) and if the main diagnosis involved dermatological (relative risk, 3.03) or oncologic disease (relative risk, 3.94). CONCLUSIONS: If we applied the results of the adult trial to our PICU, we would have to treat 31% of the children with prophylactic erythropoietin and thereby expect a reduction of one red blood cell transfusion for every 17 treated patients.  相似文献   
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