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Christopher R. Sidden MD Koenraad J. Mortele MD 《Seminars in Ultrasound, CT and MRI》2007,28(5):339-356
Cystic tumors of the pancreas are a subset of rare pancreatic tumors that vary from benign to malignant. Many have specific imaging findings that allow them to be differentiated from each other. This article aims to review the histopathologic and imaging findings of the relatively common lesions (serous microcystic adenoma, mucinous cystic tumor, intraductal papillary mucinous tumor, and solid pseudopapillary tumor) and uncommon lesions (cystic endocrine tumors, cystic metastases, cystic teratomas, and lymphangiomas) in this group. 相似文献
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Background: Established methods to stage development of third molars for forensic age estimation are based on the evaluation of radiographs, which show a 2D projection. It has not been investigated whether these methods require any adjustments in order to apply them to stage third molars on magnetic resonance imaging (MRI), which shows 3D information.Aim: To prospectively study root stage assessment of third molars in age estimation using 3 Tesla MRI and to compare this with panoramic radiographs, in order to provide considerations for converting 2D staging into 3D staging and to determine the decisive root.Subjects and methods: All third molars were evaluated in 52 healthy participants aged 14–26 years using MRI in three planes. Three staging methods were investigated by two observers. In sixteen of the participants, MRI findings were compared with findings on panoramic radiographs.Results: Decisive roots were palatal in upper third molars and distal in lower third molars. Fifty-seven per cent of upper third molars were not assessable on the radiograph, while 96.9% were on MRI. Upper third molars were more difficult to evaluate on radiographs than on MRI (p?.001). Lower third molars were equally assessable on both imaging techniques (93.8% MRI, 98.4% radiograph), with no difference in level of difficulty (p?=?.375). Inter- and intra-observer agreement for evaluation was higher in MRI than in radiographs. In both imaging techniques lower third molars showed greater inter- and intra-observer agreement compared to upper third molars. MR images in the sagittal plane proved to be essential for staging.Conclusion: In age estimation, 3T MRI of third molars could be valuable. Some considerations are, however, necessary to transfer known staging methods to this 3D technique. 相似文献
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Maarten Albersen Loes Linsen Hanna Tinel Peter Sandner Koenraad Van Renterghem 《The journal of sexual medicine》2013,10(5):1268-1277
IntroductionOverall efficacy rates of phosphodiesterase type 5 inhibitors (PDE5‐i) for erectile dysfunction (ED) are 60–70%. PDE5‐i treatment failures currently have to resort to invasive treatment options for restoration of erectile function.AimsTo assess changes in the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/protein kinase (PKG) pathway in human corpus cavernosum (HCC) of PDE5‐i nonresponders compared with healthy controls. To evaluate the effects of BAY 60‐4552, a stimulator of soluble guanylate cyclase (sGC), and vardenafil on relaxation of HCC strips from PDE5‐i nonresponders.Main Outcome MeasuresmRNA expression, morphological localization of the NO/cGMP/PKG pathway, and relaxant capacity of both compounds alone or combined. Analysis of variance, t‐test or Mann–Whitney test based upon number of groups and normality of data.MethodsHCC tissues were harvested after consent from individuals undergoing penile prosthesis implantation (patients) and potent patients undergoing transurethral surgery (healthy controls, needle biopsy). HCC tissues of patients were compared with those of healthy controls for the expression of mRNA coding for PDE5A, eNOS, PKGα1, PKG2, sGCα1, sGCα2, sGCβ1, sGCβ2, α‐smooth muscle actin (aSMA) and β‐actin by quantitative polymerase chain reaction (qPCR). The respective proteins were localized using immunofluorescence. Tissue strips of patients were precontracted with phenylepinephrine followed by incubation with 1 μM of either vardenafil or BAY 60‐4552, or both simultaneously.ResultsThe main targets in the NO/cGMP/sGC pathway were downregulated in PDE5‐i nonresponders. The pathway was morphologically located to HCC smooth muscle, of which the overall content was preserved in ED patients based on aSMA expression. BAY 60‐4552 and vardenafil have synergistic effects on relaxation of HCC of PDE5‐i nonresponders. The main limitation is the small amount of control tissue precluding functional testing on these samples.ConclusionDespite downregulation of the NO/cGMP/PKG pathway, combining BAY 60‐4552 with vardenafil significantly enhanced relaxation HCC strips of PDE5‐i nonresponders. 相似文献
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