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Chin Chin Ooi BAppSc MMedUS Foong Koon Cheah MBChB MRCP FRCR Siew Kune Wong MBBS FRCR FAMS 《Journal of clinical ultrasound : JCU》2015,43(7):438-442
We report a case of rare Castleman's disease of the kidney that mimicked a renal neoplasm with emphasis on the imaging and histologic findings. A 47‐year‐old man presented with dyspeptic symptoms. Ultrasound revealed a vascular, heterogeneous mass in the left kidney. Multiphasic CT scan confirmed an enhancing lesion with enlarged left para‐aortic lymph nodes suspicious for nodal metastases. The provisional diagnosis was renal cell carcinoma. Percutaneous biopsy yielded a diagnosis of Castleman's disease of the hyaline‐vascular type. Despite advancement in imaging modalities, differentiation of hyaline‐vascular variant of Castleman's disease from hypervascular renal neoplasm remains difficult and the final diagnosis requires histopathological confirmation. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43 :438–442, 2015 相似文献
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Jamal Kazmi Poh Choon Ooi Boon Tong Goh Min Kai Lee M. F. Mohd. Razip Wee Siti Shafura A Karim Syed Raza Ali Raza Mohd Ambri Mohamed 《RSC advances》2020,10(39):23297
Room-temperature ferromagnetism in the large and direct bandgap diluted magnetic semiconductor zinc oxide (ZnO) is attributed to the intrinsic defects and p-orbital–p-orbital (p–p) coupling interaction. However, due to oxidation, the ferromagnetism induced by defects is unstable. In the present work, the solution process synthesis route was utilized to grow pristine and bismuth-doped, highly crystalline ZnO nanowire (ZnO NW)-based samples. The FE-SEM images showed that the grown ZnO NWs have a preferred orientation along the c-axis in the (001) direction due to the anisotropic crystal nature of ZnO. X-ray photoelectron spectroscopy (XPS) confirmed the presence of Bi, and at a higher doping content, the bismuth oxide phase appeared. The XRD patterns showed the wurtzite crystal structure, and the large intensity of the (002) peak suggests that most of the reflection was from the top hexagonal face of the NWs, and thus, the wires are predominantly aligned along the c-axis. The TEM analysis further confirmed the crystal growth direction along the (001) direction. The UV-Visible absorption and PL measurements also showed a decrease in the bandgap with an increase in doping concentration, which may be associated with the sp–d exchange interaction between the localized d-electrons and band electrons of the Bi ions. Bi-doping tended to increase the PL intensity in the visible region. The magnetic properties measured by SQUID at 4 and 300 K showed ferromagnetic behaviour for both the pristine and Bi-doped samples. However, the saturation magnetization for the Bi-doped samples was higher compared to that of the pristine ZnO samples until the threshold doping value. The obtained results demonstrated that Bi-doping can be used to tune both the optical and magnetic properties of ZnO NWs, hence paving the way for future spintronics and spin-polarized optoelectronics applications.Room-temperature ferromagnetism in the large and direct bandgap diluted magnetic semiconductor zinc oxide (ZnO) is attributed to the intrinsic defects and p-orbital–p-orbital (p–p) coupling interaction. 相似文献
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Dr. P.M. Lissel LL.M 《Notfall & Rettungsmedizin》2013,16(5):389-392