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排序方式: 共有270条查询结果,搜索用时 31 毫秒
61.
This report describes the fine needle aspiration (FNA) cytologic findings in 17 rare malignant breast tumors. The series consisted of invasive cribriform carcinoma, papillary carcinoma, apocrine carcinoma, carcinoma with pseudosarcomatous metaplasia, carcinosarcoma, fibrosarcoma, malignant phyllodes tumors, primary malignant lymphomas, plasmocytoma, metastatic melanoma and metastatic renal clear cell carcinoma. Besides cytomorphology, the results of immunostaining in eight cases are presented, as is a review of the literature. It is important for rare primary malignancies, as well as for metastatic tumors, to be diagnosed, or at least have the diagnosis suggested, preoperatively by FNA and immunocytochemistry, permitting better therapy planning. 相似文献
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Curtis Huttenhower Avi I Flamholz Jessica N Landis Sauhard Sahi Chad L Myers Kellen L Olszewski Matthew A Hibbs Nathan O Siemers Olga G Troyanskaya Hilary A Coller 《BMC bioinformatics》2007,8(1):250
Background
The availability of microarrays measuring thousands of genes simultaneously across hundreds of biological conditions represents an opportunity to understand both individual biological pathways and the integrated workings of the cell. However, translating this amount of data into biological insight remains a daunting task. An important initial step in the analysis of microarray data is clustering of genes with similar behavior. A number of classical techniques are commonly used to perform this task, particularly hierarchical and K-means clustering, and many novel approaches have been suggested recently. While these approaches are useful, they are not without drawbacks; these methods can find clusters in purely random data, and even clusters enriched for biological functions can be skewed towards a small number of processes (e.g. ribosomes). 相似文献64.
Zuo D Bzdega T Olszewski RT Moffett JR Neale JH 《The Journal of biological chemistry》2012,287(26):21773-21782
The "glutamate" theory of schizophrenia emerged from the observation that phencyclidine (PCP), an open channel antagonist of the NMDA subtype of glutamate receptor, induces schizophrenia-like behaviors in humans. PCP also induces a complex set of behaviors in animal models of this disorder. PCP also increases glutamate and dopamine release in the medial prefrontal cortex and nucleus accumbens, brain regions associated with expression of psychosis. Increased motor activation is among the PCP-induced behaviors that have been widely validated as models for the characterization of new antipsychotic drugs. The peptide transmitter N-acetylaspartylglutamate (NAAG) activates a group II metabotropic receptor, mGluR3. Polymorphisms in this receptor have been associated with schizophrenia. Inhibitors of glutamate carboxypeptidase II, an enzyme that inactivates NAAG following synaptic release, reduce several behaviors induced by PCP in animal models. This research tested the hypothesis that two structurally distinct NAAG peptidase inhibitors, ZJ43 and 2-(phosphonomethyl)pentane-1,5-dioic acid, would elevate levels of synaptically released NAAG and reduce PCP-induced increases in glutamate and dopamine levels in the medial prefrontal cortex and nucleus accumbens. NAAG-like immunoreactivity was found in neurons and presumptive synaptic endings in both regions. These peptidase inhibitors reduced the motor activation effects of PCP while elevating extracellular NAAG levels. They also blocked PCP-induced increases in glutamate but not dopamine or its metabolites. The mGluR2/3 antagonist LY341495 blocked these behavioral and neurochemical effects of the peptidase inhibitors. The data reported here provide a foundation for assessment of the neurochemical mechanism through which NAAG achieves its antipsychotic-like behavioral effects and support the conclusion NAAG peptidase inhibitors warrant further study as a novel antipsychotic therapy aimed at mGluR3. 相似文献
65.
Scott CL Hartweck LM de Jesús Pérez J Chen D García JA Olszewski NE 《FEBS letters》2006,580(25):5829-5835
The capsid protein of Plum pox virus (PPV-CP) is modified with O-linked GlcNAc (O-GlcNAc). While Arabidopsis has two O-GlcNAc transferases, SECRET AGENT (SEC) and SPINDLY (SPY), previous work suggests that SEC modifies PPV-CP and that the modification plays a role in the infection process. Here, we show that when co-expressed in Escherichia coli SEC modifies PPV-CP. Deletion mapping and site-directed mutagenesis identified three threonine and a serine located near the N-terminus of PPV-CP that are modified by SEC. Two of these threonines have recently been shown to be modified in virus from plants suggesting that SEC has the same specificity in plants and E. coli. 相似文献
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Inbar Maymon Yaarit Greenboim-Wainberg Sivan Sagiv Joseph J. Kieber Menachem Moshelion Neil Olszewski David Weiss 《The Plant journal : for cell and molecular biology》2009,58(6):979-988
Specific plant developmental processes are modulated by cross-talk between gibberellin (GA)- and cytokinin-response pathways. Coordination of the two pathways involves the O-linked N -acetylglucosamine transferase SPINDLY (SPY) that suppresses GA signaling and promotes cytokinin responses in Arabidopsis. Although SPY is a nucleocytoplasmic protein, its site of action and targets are unknown. Several studies have suggested that SPY acts in the nucleus, where it modifies nuclear components such as the DELLA proteins to regulate signaling networks. Using chimeric GFP–SPY fused to a nuclear-export signal or to a glucocorticoid receptor, we show that cytosolic SPY promotes cytokinin responses and suppresses GA signaling. In contrast, nuclear-localized GFP–SPY failed to complement the spy mutation. To examine whether modulation of cytokinin activity by GA and spy is mediated by the nuclear DELLA proteins, cytokinin responses were studied in double and quadruple della mutants lacking the activities of REPRESSOR OF GA1-3 (RGA) and GA-INSENSITIVE (GAI) or RGA, GAI, RGA Like1 (RGL1) and RGL2. Unlike spy , the della mutants were cytokinin-sensitive. Moreover, when GA was applied to a cytokinin-treated quadruple della mutant it was able to suppress various cytokinin responses. These results suggest that cytosolic SPY and GA regulate cytokinin responses via a DELLA-independent pathway(s). 相似文献
67.
Johan Lennartsson Fatima Burovic Barbara Witek Aleksandra Jurek Carl-Henrik Heldin 《Cellular signalling》2010,22(6):955-960
Extracellular regulated kinase (Erk) 5 is a member of the mitogen activated protein (MAP) kinase family that has been implicated in both cell proliferation and survival. In the present study, we found that stimulation with platelet-derived growth factor (PDGF)-BB leads to a transient activation of Erk5, which was shown to be dependent on recruitment of both Src kinases and the tyrosine phosphatase Shp2 to the activated PDGF receptor β (PDGFRβ). We could also demonstrate that Shp2 docking to the receptor is critical for Src kinase activation, suggesting that Shp2 may contribute to Erk5 activation through its involvement in Src kinase activation. Under control conditions, PDGF-BB promoted a sustained Akt phosphorylation. However, reduction of the expression of Erk5 by siRNA resulted in only a transient Akt phosphorylation, and an inability of PDGF-BB to suppress caspase 3 activation and inhibit apoptotic nuclear morphological changes such as condensed or fragmented chromatin under serum-free conditions. 相似文献
68.
Anshu A. Herbert B. Cochand‐Priollet P. Cross M. Desai R. Dina J. Duskova A. Evered A. Farnsworth W. Gray S. S. Gupta K. Kapila I. Kardum‐Skelin V. Kloboves‐Prevodnik T. K. Kobayashi H. Koutselini W. Olszewski B. Onal M. B. Pitman Ž. Marinšek T. Sauer U. Schenck F. Schmitt I. Shabalova J. H. F. Smith E. Tani L. Vass P. Vielh H. Wiener 《Cytopathology》2010,21(3):147-156
Anshu, A. Herbert, B. Cochand‐Priollet, P. Cross, M. Desai, R. Dina, J. Duskova, A. Evered, A. Farnsworth, W. Gray, S. S. Gupta, K. Kapila, I. Kardum‐Skelin, V. Kloboves‐Prevodnik, T. K. Kobayashi, H. Koutselini, W. Olszewski, B. Onal, M. B. Pitman, ?. Marin?ek, T. Sauer, U. Schenck, F. Schmitt, I. Shabalova, J. H. F. Smith, E. Tani, L. Vass, P. Vielh and H. Wiener Survey of medical training in cytopathology carried out by the journal Cytopathology This report of the Editorial Advisory Board of Cytopathology gives the results of a survey of medical practitioners in cytopathology, which aimed to find out their views on the current situation in undergraduate and postgraduate training in their institutions and countries. The results show that training in cytopathology and histopathology are largely carried out at postgraduate level and tend to be organized nationally rather than locally. Histopathology was regarded as essential for training in cytopathology by 89.5% of respondents and was mandatory according to 83.1%. Mandatory cytopathology sections of histopathology were reported by 67.3% and specific examinations in cytopathology by 55.4%. The main deficiencies in training were due to its variability; there were insufficient numbers of pathologists interested in cytology and a consequent lack of training to a high level of competence. Pathologists without specific training in cytopathology signed out cytology reports according to 54.7% of responses, more often in centres where training was 3–6 months or less duration. Although 92.2% of respondents thought that specialist cytology should not be reported by pathologists without experience in general cytopathology, that practice was reported by 30.9%, more often in centres with small workloads. The survey report recommends that 6–12 months should be dedicated to cytopathology during histopathology training, with optional additional training for those wanting to carry out independent practice in cytopathology. Formal accreditation should be mandatory for independent practice in cytopathology. When necessary, temporary placements to centres of good practice should be available for trainees intending to practise independently in cytopathology. There should be adequate numbers of pathologists trained in cytopathology to a high level of competence; some of their time could be released by training cytotechnologists and trainee pathologists to prescreen cytology slides and assess adequacy of fine‐needle aspiration samples when immediate diagnosis was not required. The survey demonstrated a clear need for European and international guidelines for training in cytopathology. 相似文献
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Cristina C. Clement Elvira S. Cannizzo Maria-Dorothea Nastke Ranjit Sahu Waldemar Olszewski Norman E. Miller Lawrence J. Stern Laura Santambrogio 《PloS one》2010,5(3)