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Diverticula arising from the mitral valve are very rare. They are usually detected by echocardiography as masses arising from the cardiac valves. We present a case of an incidental finding of a diverticulum arising from the mitral valve. This was initially detected by transesophageal echocardiography, and later confirmed by pathologic appearance. The case illustrates the unique findings on echocardiography that would help to differentiate diverticula from other valvular masses.  相似文献   
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A case of primary amyloidosis, initially detected by fine-needle aspiration of the liver, is reported here. Amorphous acellular metachromatic material was seen extracellularly in between the hepatocytic cords compressing them. This material showed typical apple-green birefringence under crossed bipolars after alkaline Congo-red staining proved its amyloid nature. It was resistant to potassium permanganate pretreatment, indicating it to be of the AL type. © 1994 Wiley-Liss, Inc.  相似文献   
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Fine-needle aspiration cytology (FNAC) was performed on 195 cases of salivary gland lesions. The smears were technically adequate in 178 cases. Tissue examination was available for subsequent histocytologic correlation in 57 cases. The cytodiagnosis included inflammatory lesions (59) and benign (68) and malignant (51) tumors (total, 119). The accuracy of cytodiagnosis was 87.7% with a sensitivity of 80.9% and a specificity of 94.3%. Exact histologic typing was possible in 61.9% of the malignant tumors. Mucoepidermoid tumors and cellular-atypical pleomorphic adenoma posed difficulties in cytodiagnosis.  相似文献   
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Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration.Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy.  相似文献   
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Lasers in Medical Science - The evaluation of pigmented lesions on tattooed skin poses a diagnostic challenge for dermatologists, as a nevus may be partially or completely obscured by tattoo...  相似文献   
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BACKGROUND AND PURPOSE: Radiation therapy (RT) for cancer induces cell death by apoptosis. The major apoptotic regulatory molecules include Bcl-2, Bcl-XL (antiapoptotic), and Bax (proapoptotic) proteins. Invasive squamous cell carcinoma of the cervix is mainly treated by radiation, and hence our aim was to evaluate the changes induced by RT in the apoptotic index (AI) and to correlate this to the levels of the major pro- and antiapoptotic molecules. MATERIALS AND METHODS: Paired biopsies were obtained in 30 cases of invasive carcinoma cervix before and after 10 Gy RT. The TUNEL assay was performed to detect apoptotic nuclei and Bcl-2, Bcl-XL, and Bax proteins detected by immunohistochemistry (IHC). Statistical analysis was performed using the Spearman rank correlation coefficient test. RESULTS: Following RT, there was a significant increase in the mean AI [2.25 (+/-2.28) in post-RT vs 0.90 (+/-0.53) in the pre-RT group]. Bax, a major proapoptotic protein, was significantly increased following RT (P < 0.05), whereas the antiapoptotic Bcl-XL showed a significant decrease (P = 0.006). There was no significant change in Bcl-2 expression. The Bcl-2 and Bax IHC scores and the Bcl-2/Bax ratio did not correlate with AI in the 2 groups. There was an inverse correlation of Bcl-XL to AI in the pre-RT group (P = 0.003) but not in the post-RT group. CONCLUSIONS: RT for invasive squamous cell carcinoma of cervix results in increased apoptotic cell death with the up-regulation of Bax, a proapoptotic protein, and the down-regulation of Bcl-XL, an antiapoptotic protein, without any significant change in the levels of Bcl-2.  相似文献   
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Rationale:Nitrous oxide (NO) is a commonly used drug in medical practice, restoration, and the automobile industry. Recreational abuse is an emerging public health problem owing to its accessibility and drug properties.Patient concerns:A 25-year-old male was hospitalized with acute psychosis and lower-extremity sensorimotor proprioceptive ataxia due to nitrous oxide abuse.Diagnosis:Laboratory studies confirmed a vitamin B12 deficiency. Magnetic resonance imaging of the spinal cord showed normal findings. Electrophysiological testing confirmed length-dependent sensorimotor polyneuropathy, with a predominant motor component and axonal degeneration.Intervention and outcomes:Abstinence from toxic substances was suggested, and vitamin B12 substitution was introduced. The patient was lost to follow up.Lessons:Nitrous oxide toxicity is multisystemic and is thought to result from vitamin B12 inactivation. Recent case reports postulated direct paranodal lesions resulting from nitrous oxide consumption. Neurological, neuropsychiatric, and hematological toxicities are among those explored in this case report. Correction of the functional vitamin B12 status and nitrous oxide abstinence are essential in the treatment process.  相似文献   
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