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Biliary tract cancers (BTCs) are a group of invasive neoplasms, with increasing incidence and dismal prognosis. In advanced disease, the standard of care is represented by first-line chemotherapy with cisplatin and gemcitabine. In subsequent lines, no clear recommendations are currently available, highlighting the need for novel therapeutic approaches.The PI3K/AKT/mTOR pathway is a core regulator of cell metabolism, growth and survival, and is involved in BTCs carcinogenesis and progression. Mutations, gene copy number alterations and aberrant protein phosphorylation of PI3K, AKT, mTOR and PTEN have been thoroughly described in BTCs and correlate with poor survival outcomes.Several pre-clinical evidences state the efficacy of PI3K/AKT/mTOR pathway inhibitors in BTCs, both in vitro and in vivo. In the clinical setting, initial studies with rapamycin analogs have shown interesting activity with an acceptable toxicity profile. Novel strategies evaluating AKT and PI3K inhibitors have risen serious safety concerns, pointing out the need for improved patient selection and increased target specificity for the clinical development of these agents, both alone and in combination with chemotherapy.This review extensively describes the role of the PI3K/AKT/mTOR pathway in BTCs and examines the rationale of its targeting in these tumors, with particular focus on clinical activity, toxicities and perspectives on further development of PI3K/AKT/mTOR pathway inhibitors.  相似文献   
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ObjectiveTo analyse the length and area of corneal surface occupied by vessels, and their location in an experimental model of alkali burn-induced corneal neovascularization.MethodsAn injury to the central cornea of the right eye in 91 Sprague-Dawley rats was induced using a silver nitrate pencil. The rats were divided in 7 groups that were sacrificed 2, 4, 6, 8, 10, 12 and 14 days post-injury, and then perfused with a mixture of Chinese ink in PBS -phosphate buffer saline-. Corneas were flat-mounted processed and divided in 4 quadrants. Corneal neovascular growth parameters (length and area) and the location of these vessels were performed blind. The results were statistically analysed.ResultsNeovascular growth was observed from day 2, reaching its maximum peak in length and area on the 12th day post-injury. A slight reduction in corneal neovascularization was observed after this day. The vessels were initially located in the middle third of the stroma and tended to be observed in the anterior third during the course of the experiment.ConclusionsNeovascularisation was observed on day 2 post-injury in all sectors of corneal surface. Neovascular growth was uniform during the experiment. Neovessels were located in the middle and anterior third of the cornea.  相似文献   
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Background: Severe acute hepatitis B (SAHB) is an insufficiently described clinical entity, with relatively scarce data on anti-viral therapy available in field literature. Methods: We performed an open-label study to evaluate specific anti-viral therapy in SAHB in Bucharest, Romania, during 2005–2009. Patients were allocated to two treatment groups and one control group: Group 1 – lamivudine 100 mg/day, Group 2 – entecavir 0.5 mg/day and Group 3 – standard of care, without anti-viral therapy. The primary endpoint was hepatitis B surface antigen (HBsAg) to hepatitis B surface antibody (anti-HBs) seroconversion by 24 weeks. Additional analyses included assessment of HBsAg clearance and hepatitis B e antigen (HBeAg) to hepatitis B e antibody (anti-HBe) seroconversion. Results: In Group 1, 7/69 patients (10.14%, P = 0.032) reached HBsAg/Ab seroconversion by 24 weeks, compared with 9/21 (42.85%, P = 0.053) in Group 2 and 25/110 (22.72%) in Group 3. HBsAg clearance by 24 weeks: 16/69 patients (23.18%, P = 0.027) in Group 1, 11/21 (52.38%, P = 0.256) in Group 2 and 43/110 (39.09%) in Group 3. HBeAg/Ab seroconversion: 46/61 (75.40%, P = 0.399) in Group 1, 9/19 (47.36%, P = 0.001) in Group 2 and 74/100 (74.00%) in Group 3. Conclusion: Anti-viral therapy can be considered for managing selected cases of SAHB. Biochemical as well as virological parameters need to orient the choice of the anti-viral agent. Lamivudine displayed a greater decrease in viral load compared to controls, but it was associated with lower levels of HBsAg to anti-HBs seroconversion. Patients treated with entecavir showed a better response in terms of HBs seroconversion by 24 weeks.  相似文献   
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Objective: Evaluation of the Sennheiser HD 202 II supra-aural headphones as an alternative headphone to enable more affordable hearing screening. Design: Study 1 measured the equivalent threshold sound pressure levels (ETSPL) of the Sennheiser HD 202 II. Study 2 evaluated the attenuation of the headphones. Study 3 determined headphone characteristics by analyzing the total harmonic distortion (THD), frequency response and force of the headband. Study sample: Twenty-five participants were included in study 1 and 15 in study 2 with ages ranging between 18 and 25. No participants were involved in study 3. Results: The Sennheiser HD 202 II ETSPLs (250–16000?Hz) showed no significant effects on ETSPL for ear laterality, gender or age. Attenuation was not significantly different (p?>?0.01) to TDH 39 except at 8000?Hz (p?3%. Conclusion: Sennheiser HD 202 II supra-aural headphones can be used as an affordable headphone for screening audiometry provided reported MPANLs, maximum intensities and ETSPL values are employed.  相似文献   
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