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91.
We report a series of seven patients who underwent fine-needle aspiration (FNA) for clinically apparent parotid gland lesions. In all seven cases, numerous to abundant polyhedral, multifaceted (nontyrosine) crystalloids were noted in the background of scanty cellular specimens composed predominantly of oncocytic cells. Subsequent surgical excision showed that three of the seven glands revealed sialolithiasis and sialadenitis without evidence of neoplasia. The histology of the remaining four cases consisted of two Warthin's tumor, one oncocytic papillary cystadenoma, and one cellular benign mixed tumor. In all seven cases the nontyrosine crystalloids were found in highest concentrations in cystic spaces lined with oncocytic metaplastic cells. We conclude that nontyrosine cystalloids can be associated with both neoplastic and nonneoplastic salivary gland disease, and they may be a product of oncocytic cell secretion. Diagn. Cytopathol. 2000;22:167-171.  相似文献   
92.
Fine-needle aspiration biopsy is a reliable and accurate method for the endoscopic diagnosis of gastrointestinal malignancies and it is particularly well suited for evaluation of submucosal lesions. We report the cytopathologic findings of a case of malignant carcinoid tumor of a 44-year-old male who presented with melena and a nonhealing duodenal ulcer. Endoscopic ultrasound examination revealed a submucosal lesion in the pyloric region. Fine-needle aspiration revealed abundant cellularity with tumor cells arranged in sheets and loose groups and dispersed single cells in a clean background. Papillary fragments, capillaries cuffed by tumor cells, and rosette formation were also noted. The cells were moderate in size, round to oval, with a small subpopulation of spindle-shaped cells. The nuclei were uniform, round to oval, with smooth nuclear borders. The chromatin pattern was finely granular with a salt-and-pepper appearance. The cytoplasm of the cells was small to moderate in amount, pale, and showed fine granularity. The differential diagnosis included a neuroendocrine neoplasm vs. an epithelioid gastrointestinal stromal tumor. The tumor cells were focally positive for chromogranin and negative for CD34, supporting the diagnosis of a neuroendocrine neoplasm. The differential diagnosis of primary gastrointestinal carcinoid tumors from gastrointestinal stromal tumors can be very difficult in cytologic material. In cases when diagnostic material is scant, or only present on one smear, the use of smear division and cell transfer in order to perform immunocytochemical stains may be of considerable value to confirm the neuroendocrine nature of the neoplasms.  相似文献   
93.
94.
Primary malignant lymphomas of the breast (PBL) are uncommon constituting only 0.04 to 0.53% of malignant breast neoplasms. We wish to report the clinical, cytological and histologic findings of PBL diagnosed in a 52 years old female.  相似文献   
95.
One of the most valuable tests for the rapid presumptive identification of Candida albicans is germ tube production. Previously researchers have concluded superior results with serum in germ tube test. However, handling of pooled human serum has danger of acquisition of hepatitis and HIV infections. Therefore, in the present study we compared various media--pooled human serum, sterile horse serum, peptone water and tryptic soy broth. It was observed that human serum remains to be the best with 100% positivity for identification of C. albicans followed by horse serum (76.3%), peptone water (61.8%) and tryptic soy broth (61.8%).  相似文献   
96.
Post cardiac injury syndrome (PCIS) is known to occur following myocardial infarction, cardiac surgery, blunt chest trauma, percutaneous left ventricular puncture and pace-maker implantation. The diagnosis is one of exclusion. We report a case of PCIS following cardiac surgery who showed false positive IgG, IgM antibodies to antigen A60 of Mycobacterium tuberculosis in pleural fluid.  相似文献   
97.
98.
Although atherosclerosis progresses in an indolent state for decades, the rupture of plaques creates acute ischemic syndromes that may culminate in myocardial infarction and stroke. Mechanical forces and matrix metalloproteinase activity initiate plaque rupture, whereas tissue inhibitors of metalloproteinases have an important (albeit indirect) role in plaque stabilization. In this paper, an enzyme that could directly stabilize the plaque is described. Tissue transglutaminase (TG) catalyzes the formation of epsilon(gamma-glutamyl)lysine isopeptide bonds that are resistant to enzymatic, mechanical, and chemical degradation. We performed immunohistochemistry for TG in atherosclerotic human coronary and carotid arteries. TG was most prominent along the luminal endothelium and in the medium of the vessels with a distribution mirroring that of smooth muscle cells. Variable, often prominent, immunoreactivity for TG was also seen in the intima, especially in regions with significant neovascularization. Additionally, TG was detected in fibrous caps and near the "shoulder regions" of some plaques. A monoclonal antibody to the transglutaminase product epsilon(gamma-glutamyl)lysine isopeptide demonstrated co-localization with TG antigen. Transglutaminase activity was found in 6 of 14 coronary artery atherectomy samples. Cross-linking of TG substrates such as fibrinogen, fibronectin, vitronectin, collagen type I, and protease inhibitors stabilized the plaque. Furthermore, the activation of transforming growth factor-beta-1 by TG might be an additional mechanism for the promotion of plaque stabilization and progression by increasing the synthesis of extracellular matrix components.  相似文献   
99.
During the last 4 yr, fine-needle aspiration cytology (FNAC) has been employed in 1,474 patients in 0-15-yr age group at our institute. Of these, 245 patients were found to have malignant disease, including primitive neuroectodermal tumors, hepatoblastoma, nephroblastoma, sarcoma, and epithelial malignancies. Four metastases from medulloblastoma and two each from astrocytoma and meningioma were confirmed without open biopsy. FNAC interpretation was easy when cytologic findings were correlated with relevant clinical and radiologic data.  相似文献   
100.
We report a patient with bilateral microphthalmia with cyst, limb anomalies, and multiple facial malformations. This patient has clinical features similar to Waardenburg ophthalmo-acromelic syndrome, cerebro-oculo-nasal syndrome, and craniotelencephalic dysplasia. Although all of these syndromes are characterized by microphthalmia, the presently reported patient does not have the complete pattern of any of these syndromes, It is possible that he has a previously undescribed syndrome, most closely related to the cerebro-oculo-nasal syndrome with malformations outside the craniofacial region. More case reports are needed to further delineate this possibly new syndrome.  相似文献   
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