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Pancreatoblastoma or infantile pancreatic carcinoma is a rare pancreatic tumor with distinct acinar and squamoid cell differentiation that generally affects infants and young children. Ultrasound and CT scan may be useful but preoperative diagnosis is often quite difficult. The outcome is generally favourable. A such case of 10 years old boy with an abdominal mass is being presented.  相似文献   
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Skeletal metastasis as a primary presentation of gall bladder carcinoma is rare. A 50-year-old lady presented with neck pain and weakness in her right upper limb of 3 months duration. Clinical and imaging work-up suggested locally advanced gall bladder carcinoma with metastasis to cervical vertebra and sternum. Only one case till date has been reported where the patient presented with neurological symptoms due to pathological fracture secondary to metastasis from an occult gall bladder carcinoma. Although rare, an occult gall bladder cancer may present with neurological symptoms due to pathological fracture of spine secondary to metastasis. We present a brief review of literature of patients who presented with skeletal metastases in clinically silent gall bladder malignancy. Palliative care issues in advanced gall bladder carcinoma have also been discussed.  相似文献   
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Tropospheric ozone (O3) is the most important regional atmospheric pollutant causing risk to food production across the globe due to its phytotoxicity and prevalence over agricultural areas. Peak O3 concentrations have declined in Europe and North America due to reductions in precursors during the last decades, however, emissions of O3 precursors have increased in Asia. The current critical level of ozone is determined by the threshold for yield loss which is based on the seasonal sum of the external concentration above 40?ppb. In the present article, the impact of tropospheric O3 on crop photosynthesis, defense mechanism, growth, reproductive processes and yield of crop plants have been documented. O3 upon its entry into the leaf intercellular spaces rapidly forms reactive oxygen species and reacts with components of the leaf apoplast to initiate a complex set of responses that constitute variable countermeasures by antioxidative enzymes. Ozone affects photosynthetic process by influencing photosynthetic pigments, chlorophyll fluorescence kinetics and electron transport as well as carbon fixation in terms of decreased Rubisco activity and quantity. Translocation and allocation pattern of photosynthate also get influenced under O3, which affect reproductive processes and yield of crops. Plant species and cultivars exhibit a range of sensitivity to O3, which is identifiable in terms of biochemical, physiological, molecular and yield responses. Hence, understanding of cultivar sensitivity in context to O3 would be helpful in development of potential O3 biomarkers and O3 tolerant variables.  相似文献   
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After radical resection of cancer of the right colonic flexure, a parietal defect can be created in case of duodenal invasion. In this paper the authors describe an "easy and safe" duodenoplasty surgical technique using an ileal patch.  相似文献   
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The different rotameric conformations of imidazo-[1,2-a]pyrazine have been synthesized and characterized by means of different experimental techniques, such as NMR, FTIR, and absorption spectroscopy and quantum chemical calculations. The different conformations were stabilized by hydrogen bonds, such as OH⋯N, ArH⋯N and ArH⋯ArH. The ground state optimizations and potential energy surface (PES) scanning profiles produced using density functional theory (DFT) show two stable rotameric forms for each molecule. The relative population of the conformations is affected by the strength of the hydrogen bonds. The calculated absorption spectra and isotopic shielding constants were acquired by time-dependent density functional theory (TD-DFT) and gauge invariant atomic orbitals (GIAO)-DFT, respectively. The strength of the hydrogen bonding interactions that resulted in the different conformations was studied by quantum theory of atoms in molecules (QTAIM).

The different rotameric conformations of imidazo-[1,2-a]pyrazine have been synthesized and characterized by means of different experimental techniques, such as NMR, FTIR, and absorption spectroscopy and quantum chemical calculations.  相似文献   
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