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Epithelial‐myoepithelial carcinoma (EMC) is a rare salivary gland malignancy with variable cytologic findings. Its rarity, variable morphologic findings, and similarities with more common salivary gland entities make it a difficult cytologic diagnosis. As the name signifies, the key feature of this tumor is presence of an epithelial and myoepithelial component. However, when one of these two components is scant on the fine needle aspiration (FNA) smears, it may be overlooked. We present a case from a 62 year‐old female who presented to the clinic with a parotid nodule and episodes of sharp, throbbing pain. A fine needle aspiration was performed which revealed a highly cellular specimen comprised primarily of aggregates of cells with small, round nuclei and scant to absent cytoplasm. Abundant hyaline stromal material was also noted. The case was signed out as basaloid neoplasm with a recommendation for surgical resection. The subsequent resection specimen revealed EMC. By reviewing the FNA specimen following the surgical resection of the tumor, we were able to utilize the benefit of hindsight to more clearly identify the subtle, biphasic components of the tumor. Diagn. Cytopathol. 2016;44:422–425. © 2016 Wiley Periodicals, Inc.  相似文献   
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Using digital technology, we have assembled a virtual laboratory manual (VLM) that is a Web-based copy of our traditional laboratory manual. The VLM is used to enhance traditional laboratory instruction in histology. For each reference in the VLM to either a histological slide or an electron micrograph (EM), hyperlinks are included that download digital images derived from the students' glass slide sets or scanned EMs. The VLM serves as an atlas of digital images for concurrent study of similar sections by light microscopy during laboratory sessions. In addition, students can review the images from the VLM at remote locations. We have encouraged continued use of light microscopes in laboratories by basing the majority of practical examination identifications on analysis of marked histological slides that require students to use their own microscopes. The VLM provides the convenience of a Web-based resource with high-quality images, yet allows retention of the many excellent traditional aspects of our course. An example of a VLM laboratory on epithelium is available online (http://users.von.uc.edu/michaeje/VLM-Epithelium/exLab4.pdf).  相似文献   
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Hexanucleotide repeat expansions in C9ORF72 are a common cause of familial and apparently sporadic amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). The mechanism by which expansions cause neurodegeneration is unknown, but current evidence supports both loss-of-function and gain-of-function mechanisms. We used pooled next-generation sequencing of the C9ORF72 gene in 389 ALS patients to look for traditional loss-of-function mutations. Although rare variants were identified, none were likely to be pathogenic, suggesting that mutations other than the repeat expansion are not a common cause of ALS, and providing supportive evidence for a gain-of-function mechanism. We also show by repeat-primed PCR genotyping that the C9ORF72 expansion frequency varies by geographical region within the United States, with an unexpectedly high frequency in the Mid-West. Finally we also show evidence of somatic instability of the expansion size by Southern blot, with the largest expansions occurring in brain tissue.  相似文献   
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To determine whether the effects of low-level lead exposure persist, we reexamined 132 of 270 young adults who had initially been studied as primary school-children in 1975 through 1978. In the earlier study, neurobehavioral functioning was found to be inversely related to dentin lead levels. As compared with those we restudied, the other 138 subjects had had somewhat higher lead levels on earlier analysis, as well as significantly lower IQ scores and poorer teachers' ratings of classroom behavior. When the 132 subjects were reexamined in 1988, impairment in neurobehavioral function was still found to be related to the lead content of teeth shed at the ages of six and seven. The young people with dentin lead levels greater than 20 ppm had a markedly higher risk of dropping out of high school (adjusted odds ratio, 7.4; 95 percent confidence interval, 1.4 to 40.7) and of having a reading disability (odds ratio, 5.8; 95 percent confidence interval, 1.7 to 19.7) as compared with those with dentin lead levels less than 10 ppm. Higher lead levels in childhood were also significantly associated with lower class standing in high school, increased absenteeism, lower vocabulary and grammatical-reasoning scores, poorer hand-eye coordination, longer reaction times, and slower finger tapping. No significant associations were found with the results of 10 other tests of neurobehavioral functioning. Lead levels were inversely related to self-reports of minor delinquent activity. We conclude that exposure to lead in childhood is associated with deficits in central nervous system functioning that persist into young adulthood.  相似文献   
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Diagnosis of metastatic lesions to the stomach by salvage cytology   总被引:1,自引:0,他引:1  
Summary Secondary neoplasms of the stomach are rare and are often clinical and diagnostic problems. Three patients with bleeding volcano-like ulcers were diagnosed by combined endoscopic salvage cytology and surgical biopsy as having metastatic submucosal lesions from hematologic spread. The combination of endoscopic appearance, clinical findings, and tissue and cytologic examination can lead to the correct diagnosis. The results from these cases support the utility of this cytologic technique in combination with biopsy in this clinical setting.  相似文献   
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Background contextCharacteristic changes of the facet joints, including synovial cysts, facet joint hypertrophy, and facet joint effusions, on magnetic resonance imaging (MRI) and computed tomography have been associated with lumbar degenerative spondylolisthesis. The cervical facets have not been examined for associations with cervical degenerative spondylolisthesis similar to those seen in the lumbar spine.PurposeTo define abnormalities of the facet joints seen on supine MRI that correlate with cervical spondylolisthesis seen on upright radiographs.Study designRetrospective radiographic review of consecutive patients with a universally applied standard.Patient sampleA total of 204 consecutive patients from a single institution, with both an MRI and upright radiographs, were reviewed.Outcome measuresSagittal plane displacement on upright lateral radiographs was compared with MRI. The total area of the facet joint and the amount of facet joint asymmetry were measured on an axial MRI.MethodsThe data were analyzed to determine a significant association between the cervical degenerative spondylolisthesis and the following: facet joint asymmetry, increased total area of the facet joint, and age.ResultsDegenerative spondylolisthesis was seen in 26 patients at C3–C4 and in 27 patients at C4–C5. Upright radiographs identified significantly more degenerative spondylolisthesis than MRIs at levels C3–C4 and C4–C5, 26 versus 6 (p<.001) at C3–C4 and 27 versus 11 (p<.001) at C4–C5. Patients with degenerative spondylolisthesis were more likely to be older, have a larger total facet area, and more facet asymmetry at C3–C4 and C4–C5 (p<.05).ConclusionsSupine MRIs underestimate sagittal displacement compared with upright lateral radiographs. Asymmetric facet hypertrophy at C3–C4 and C4–C5 is associated with degenerative spondylolisthesis on upright lateral films even in the absence of anterolisthesis on supine MRIs.  相似文献   
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