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The present research work was carried out to determine stability of cefditoren pivoxil, an orally absorbed prodrug that is rapidly hydrolysed by intestinal esterases to the active cephalosporin cefditoren. Cefditoren was subjected to stress conditions recommended by the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use guideline Q1A (R2). Cefditoren pivoxil was susceptible for degradation under acidic, alkaline and neutral hydrolytic conditions while it was stable under photolytic and thermal stress conditions. Separation of cefditoren and degradation products were carried out by using HPLC. The unknown degradation products were characterized by liquid chromatography-mass spectrometry/time of flight studies. Structures were proposed for each fragment based on best possible molecular formula and complete degradation pathways were reported for cefditoren and its degradants.  相似文献   
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ObjectivesCocaine is the second most frequently used illicit drug worldwide (after cannabis), and cocaine use disorder (CUD)-related deaths increased globally by 80% from 1990 to 2013. There is yet to be a regulatory-approved treatment. Emerging preclinical evidence indicates that deep brain stimulation (DBS) of the nucleus accumbens may be a therapeutic option. Prior to expanding the costly investigation of DBS for treatment of CUD, it is important to ensure societal cost-effectiveness.AimsWe conducted a threshold and cost-effectiveness analysis to determine the success rate at which DBS would be equivalent to contingency management (CM), recently identified as the most efficacious therapy for treatments of CUDs.Materials and MethodsQuality of life, efficacy, and safety parameters for CM were obtained from previous literature. Costs were calculated from a societal perspective. Our model predicted the utility benefit based on quality-adjusted life-years (QALYs) and incremental-cost-effectiveness ratio resulting from two treatments on a one-, two-, and five-year timeline.ResultsOn a one-year timeline, DBS would need to impart a success rate (ie, cocaine free) of 70% for it to yield the same utility benefit (0.492 QALYs per year) as CM. At no success rate would DBS be more cost-effective (incremental-cost-effectiveness ratio <$50,000) than CM during the first year. Nevertheless, as DBS costs are front loaded, DBS would need to achieve success rates of 74% and 51% for its cost-effectiveness to exceed that of CM over a two- and five-year period, respectively.ConclusionsWe find DBS would not be cost-effective in the short term (one year) but may be cost-effective in longer timelines. Since DBS holds promise to potentially be a cost-effective treatment for CUDs, future randomized controlled trials should be performed to assess its efficacy.  相似文献   
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Adenomatoid odontogenic tumor (AOT) is an uncommon benign tumor of odontogenic origin composed of odontogenic epithelium in a variety of histopathological patterns. These lesions are usually solid but are occasionally cystic. AOT has been reported to occur in association with odontogenic cysts. Very few cases have been described that arise in association with a dentigerous cyst. A systematic search of the English-language medical literature in PubMed and Medline search (keywords adenomatoid odontogenic tumor, dentigerous cyst) data bases revealed only ten such cases.The present case is very unique, exceptional and first of this kind that occurred in the posterior mandible associated with an impacted lower first premolar in a 19-year old female patient. The intraosseous follicular AOT, as this case reported here, frequently resemble dentigerous cysts. There is an uncertainty whether the lining of an associated cyst represents a true dentigerous cyst, cystic change within an AOT or may represent a distinct entity. We believe that this case represents an odontogenic cyst with neoplastic change. Hence, in such cases, the final diagnosis should be made on the basis of histological examination of extensive tissue sampling of entire excised tissue specimen. Further studies to determine whether the AOT derived from an odontogenic cyst could represent a distinct variant are to be done.  相似文献   
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