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991.
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Introduction  

Hypoxia and hypoxemia can lead to an unfavorable outcome after severe trauma, by both direct and delayed mechanisms. Prehospital intubation is meant to ensure pulmonary gas exchange. Limited evidence exists regarding indications for intubation after trauma. The aim of this study was to analyze prehospital intubation as an independent risk factor for the posttraumatic course of moderately injured patients. Therefore, only patients who, in retrospect, would not have required intubation were included in the matched-pairs analysis to evaluate the risks related to intubation.  相似文献   
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Purpose  

Although widely used, there is a lack of evidence concerning the diagnostic accuracy of C-reactive protein (CRP) and white blood cell counts (WBCs) in the postoperative period. The aim of this study was to evaluate the diagnostic accuracy of CRP and WBCs in predicting postoperative inflammatory complications after open resection of colorectal cancer.  相似文献   
999.
Micelles are the simplest example of self-assembly found in nature. As many other colloids, they can self-assemble in aqueous solution to form ordered periodic structures. These structures so far all exhibited classical crystallographic symmetries. Here we report that micelles in solution can self-assemble into quasicrystalline phases. We observe phases with 12-fold and 18-fold diffraction symmetry. Colloidal water-based quasicrystals are physically and chemically very simple systems. Macroscopic monodomain samples of centimeter dimension can be easily prepared. Phase transitions between the fcc phase and the two quasicrystalline phases can be easily followed in situ by time-resolved diffraction experiments. The discovery of quasicrystalline colloidal solutions advances the theoretical understanding of quasicrystals considerably, as for these systems the stability of quasicrystalline states has been theoretically predicted for the concentration and temperature range, where they are experimentally observed. Also for the use of quasicrystals in advanced materials this discovery is of particular importance, as it opens the route to quasicrystalline photonic band gap materials via established water-based colloidal self-assembly techniques.  相似文献   
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Our objective is to outline the utility of adrenal venous sampling (AVS) with measurements of metanephrine to normetanephrine ratios for diagnostic localization of phaeochromocytoma in a patient with normal plasma levels of catecholamines. A 53-year-old-woman was referred for evaluation of recurrent pheochromocytoma following a right adrenalectomy 14 years earlier. Diagnosis of recurrent disease was established from elevations in plasma metanephrines with normal levels of catecholamines. Magnetic resonance imaging indicated two 1-2 cm masses in the right surgical bed and another 1-1.5 cm mass in the left adrenal. These masses were negative on (123)I-metaiodobenzylguanidine scintigraphy. There was no evidence of a hereditary syndrome. We, therefore, carried out two investigational approaches to identify the tumor masses. Hybrid positron emission tomography/computed tomography with (68)Ga-DOTATOC ((68)Ga-DOTATOC-PET/CT) confirmed the presence of recurrent disease in the right surgical bed and also suggested additional left adrenal involvement. Normal plasma catecholamines precluded the use of adrenal venous sampling (AVS) with catecholamine measurements. Hence, we performed AVS with measurements of plasma metanephrines, which were 4- to 7-fold higher in the left adrenal vein than in central venous plasma. We observed a reversal of the normally high metanephrine to normetanephrine ratio (mean value ± SD 5.28 ± 1.86; range 3.36-8.84, n = 13) to 0.73, establishing the presence of a left adrenal pheochromocytoma. Surgical pathology confirmed bilateral disease. This case highlights a scenario where a combination of (68)Ga-DOTATOC-PET/CT and AVS with measurement of the metanephrine to normetanephrine ratio was crucial for the preoperative assessment of a patient with bilateral pheochromocytoma.  相似文献   
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