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In order to define the cytologic features of pulmonary involvement by mycosis fungoides, 15 respiratory cytology specimens from four patients with biopsy-proven pulmonary mycosis fungoides were reviewed. The presence in sputum smears of occasional small or large cerebriform mononucleated cells against a background of numerous atypical lymphocytic cells permitted an antemortem cytologic diagnosis of probable or definite dissemination of mycosis fungoides with pulmonary involvement. Similar cells were seen in aspiration smears. The lymphocytic infiltrates were similar to those in corresponding skin biopsies in each case. The distinctive cytologic findings in these cases may therefore help to determine the underlying etiology of pulmonary lesions and may contribute to the antemortem diagnosis of visceral dissemination of mycosis fungoides. 相似文献
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S Rosen 《Current biology : CB》1999,9(18):R698-R700
Recent studies have found associations between auditory processing deficits and language disorders such as dyslexia; but whether the former cause the latter, or simply co-occur with them, is still an open question. 相似文献
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Daniel J. Arsenault Byong H. Yoo Kirill V. Rosen Neale D. Ridgway 《The Journal of biological chemistry》2013,288(1):633-643
Cancer cells have enhanced lipogenic capacity characterized by increased synthesis of fatty acids and complex lipids, including phosphatidylcholine (PC). As the rate-limiting enzyme in the CDP-choline pathway for PC synthesis, CTP:phosphocholine cytidylyltransferase α (CCTα) is implicated in the provision of membranes and bioactive lipids necessary of cell proliferation. In this study, we assessed the role of CCTα in malignant intestinal epithelial cells transformed with activated H-ras (IEC-ras). Three IEC-ras clones had significant up-regulation CCTα expression, but PC synthesis and in vitro activity of CCTα were similar to control IEC. RNA interference of CCTα in adherent IEC-ras did not affect PC synthesis, confirming that the enzyme was relatively inactive. However, CCTα silencing in ras-transformed IEC reduced anchorage-independent growth, a criterion for malignant transformation, as well as tumorigenicity in mice. Relative to their adherent counterparts, detached IEC-ras had increased PC synthesis that was attenuated by inducible CCTα silencing. Detachment of IEC-ras was accompanied by increased CCTα phosphorylation and cytosolic enzyme activity. We conclude that the expanded pool of CCTα in IEC-ras is activated by detachment. This provides the increased PC biosynthetic capacity that contributes to malignant transformation of intestinal epithelial cells when detached from the extracellular matrix. 相似文献
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