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Differentiation of salivary gland acinic cell carcinoma from mucoepidermoid carcinoma can be diagnostically challenging as both may have prominent mucin production. P63 is a p53 homologue required for limb and epidermal morphogenesis. It is expressed in basal and myoepithelial cells of normal salivary gland tissues. In this immunohistochemical study, we examined the expression of p63 in salivary gland acinic cell and mucoepidermoid carcinomas (MEC) and its use in differentiating these two entities. A search was performed and appropriate cases were selected from Lifespan Hospital System archives as well as the consult archives of one author (DRG). 31 salivary gland acinic cell carcinomas (ACC) and 24 MEC were examined for p63 expression by immunohistochemistry. The nuclear immunoreactivity was examined by both authors and was graded semi-quantitatively with negative being less than 10 % of cells staining. Positive staining was graded as follows: 10–25 % of tumor cells staining was weakly positive, 26–75 % of tumor cells staining was moderately positive, and 76–100 % of tumor cells staining was strongly positive. Negative nuclear staining of the tumor cells was seen in 30/31 (96 %) of salivary gland ACC while 1/31 (3 %) showed diffuse nuclear staining of the tumor cells. This latter case was later reclassified as mammary analogue secretory carcinoma following confirmatory molecular testing for the ETV6-NTRK3 fusion gene. Strong positive nuclear staining of the tumor cells was seen in 24 (100 %) of salivary gland MEC cases. P63 is an immunohistochemical stain that can potentially aid in differentiating unusual ACC with prominent mucin production from MEC of the salivary gland. According to this study, acinic cell carcinoma is always negative for p63 immunoreactivity while mucoepidermoid carcinoma is always positive. 相似文献
994.
The purpose of this study was to evaluate the effectiveness of online mastery quizzes in enhancing dental students' learning and preparedness for anatomy examinations. First-year dental students taking an integrated anatomy course at The Ohio State University were administered online mastery quizzes, made available for five days before each examination. The mastery quizzes were comprised of ten multiple-choice questions representative of the upcoming examination in content and difficulty. The students were allowed to access this resource as many times as they desired during the five-day window before each examination; the highest score for each student was added to his or her final course grade. The results indicate that almost all the students took advantage of this resource to reinforce content, clarify concepts, and prepare for the examinations. Statistical analyses of the students' exam performance showed that the mastery quizzes neither improved nor reduced their exam scores, but multiple regression analyses showed that the initial mastery quiz scores had a predictive value for their examination performance, suggesting a potential for mastery quizzes as an intervention tool for such a course. Online mastery quizzes, when used effectively, may be an effective resource to further engage dental and other students in educational endeavors and examination preparation and as a predictor of success. 相似文献
995.
Nancy?ByattEmail author Kathleen?Biebel Gifty?Debordes-Jackson Rebecca?S.?Lundquist Tiffany?A.?Moore Simas Linda?Weinreb Douglas?Ziedonis 《The Psychiatric quarterly》2013,84(2):169-174
This is the first study evaluating obstetrics and gynecology (OB/Gyn) provider and staff perceptions of barriers to accessing pharmacotherapy for perinatal depression outside the obstetric setting. Four, 90 min focus groups were conducted with OB/Gyn physicians, advance practice nurses, and support and nursing staff (n = 28). Data were analyzed with a grounded theory approach. Participants perceived that community mental health providers and pharmacists often do not want to participate in pharmacotherapy for perinatal women. Participants believed the solution is training for community mental health providers in the risks and benefits of pharmacotherapy for perinatal depression and improved communication between OB/Gyn’s and community mental health providers. Community mental health provider and pharmacist reluctance to provide pharmacotherapy hinders OB/Gyn’s perceived ability to address perinatal depression. Community mental health provider and pharmacist training are needed to mitigate precipitous discontinuation of treatment and to improve access to pharmacotherapy for perinatal women. 相似文献
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997.
Jachin A. Monteon Hongying Wang Julio Martinez‐Trujillo J. Douglas Crawford 《The European journal of neuroscience》2013,37(11):1754-1765
The frontal eye field (FEF), in the prefrontal cortex, participates in the transformation of visual signals into saccade motor commands and in eye–head gaze control. The FEF is thought to show eye‐fixed visual codes in head‐restrained monkeys, but it is not known how it transforms these inputs into spatial codes for head‐unrestrained gaze commands. Here, we tested if the FEF influences desired gaze commands within a simple eye‐fixed frame, like the superior colliculus (SC), or in more complex egocentric frames like the supplementary eye fields (SEFs). We electrically stimulated 95 FEF sites in two head‐unrestrained monkeys to evoke 3D eye–head gaze shifts and then mathematically rotated these trajectories into various reference frames. In theory, each stimulation site should specify a specific spatial goal when the evoked gaze shifts are plotted in the appropriate frame. We found that these motor output frames varied site by site, mainly within the eye‐to‐head frame continuum. Thus, consistent with the intermediate placement of the FEF within the high‐level circuits for gaze control, its stimulation‐evoked output showed an intermediate trend between the multiple reference frame codes observed in SEF‐evoked gaze shifts and the simpler eye‐fixed reference frame observed in SC‐evoked movements. These results suggest that, although the SC, FEF and SEF carry eye‐fixed information at the level of their unit response fields, this information is transformed differently in their output projections to the eye and head controllers. 相似文献
998.
999.
Rachael I. Scahill Nicola Z. Hobbs Miranda J. Say Natalie Bechtel Susie M.D. Henley Harpreet Hyare Douglas R. Langbehn Rebecca Jones Blair R. Leavitt Raymund A.C. Roos Alexandra Durr Hans Johnson Stéphane Lehéricy David Craufurd Christopher Kennard Stephen L. Hicks Julie C. Stout Ralf Reilmann Sarah J. Tabrizi the TRACK‐HD investigators 《Human brain mapping》2013,34(3):519-529
TRACK‐HD is a multicentre longitudinal observational study investigating the use of clinical assessments and 3‐Tesla magnetic resonance imaging as potential biomarkers for future therapeutic trials in Huntington's disease (HD). The cross‐sectional data from this large well‐characterized dataset provide the opportunity to improve our knowledge of how the underlying neuropathology of HD may contribute to the clinical manifestations of the disease across the spectrum of premanifest (PreHD) and early HD. Two hundred and thirty nine gene‐positive subjects (120 PreHD and 119 early HD) from the TRACK‐HD study were included. Using voxel‐based morphometry (VBM), grey and white matter volumes were correlated with performance in four domains: quantitative motor (tongue force, metronome tapping, and gait); oculomotor [anti‐saccade error rate (ASE)]; cognition (negative emotion recognition, spot the change and the University of Pennsylvania smell identification test) and neuropsychiatric measures (apathy, affect and irritability). After adjusting for estimated disease severity, regionally specific associations between structural loss and task performance were found (familywise error corrected, P < 0.05); impairment in tongue force, metronome tapping and ASE were all associated with striatal loss. Additionally, tongue force deficits and ASE were associated with volume reduction in the occipital lobe. Impaired recognition of negative emotions was associated with volumetric reductions in the precuneus and cuneus. Our study reveals specific associations between atrophy and decline in a range of clinical modalities, demonstrating the utility of VBM correlation analysis for investigating these relationships in HD. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc. 相似文献
1000.
Hereditary hemorrhagic telangiectasia (HHT) is an inherited mucocutaneous disease characterized by recurrent epistaxis, lesions on skin and oral mucosa, and arteriovenous malformations of the soft tissues. This article describes the treatment of a 64-year-old woman with a bleeding nodule, which was diagnosed as an arteriovenous malformation of the gingival mucosa. She was treated using sclerotherapy. Patients with HHT can be treated in the dental office and vascular malformations of these patients can be successfully managed with sclerotherapy, which eliminates the need for invasive surgical procedures and the possibility of postsurgical complications. 相似文献