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41.
Margret S. Magid Wallace G. Campbell Jr MD Sutini Ngadiman Thomas A. Godwin MD Robert Ward 《Fetal and pediatric pathology》1997,17(2):303-314
We report a case of an infantile myofibromatosis with hemangiopericytoma-like features arising in the tongue of a 5-month-old female infant. Many authors now classify neoplasms as infantile myofibromatosis that were previously called infantile hemangiopericytoma. The ultrastructural features of our tumor illustrate its biphasic nature and provide a possible explanation for its histogenesis. Infantile myofibromatosis, including those diagnosed as infantile hemangiopericytomas, rarely arise in any intraoral location. Despite the generally good prognosis associated with these neoplasms, complete surgical excision is recommended to avoid recurrences. 相似文献
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Chad Galer Anthony Yonkers Wallace Duff Barbara Heywood 《Otolaryngology--head and neck surgery》2007,136(2):241-245
OBJECTIVE: To examine the clinical significance of acoustic data recorded by the SNAP home polysomnography system (SNAP Laboratories, Glenview, IL). STUDY DESIGN AND SETTING: Retrospective analysis of SNAP data from 59 patients undergoing evaluation for sleep apnea at the University of Nebraska Medical Center and an associated private practice in Omaha, NE. RESULTS: Snoring did not correlate with anthropometric variables such as body mass index and neck circumference. Statistical analysis showed no correlation between respiratory disturbance index and the maximum or average loudness of snoring. Average loudness was predictive of the presence of sleep apnea. Spectral analysis of snoring sonography found that the proportion of snoring events associated with a palatal source correlated strongly with the loudness of snoring. CONCLUSION: These data suggest that analysis of snoring has limited utility in the evaluation of the patient with sleep apnea but may be able to select patients who would benefit from palatal procedures to reduce snoring. 相似文献
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Characterization of RAFTK, a novel focal adhesion kinase, and its integrin-dependent phosphorylation and activation in megakaryocytes 总被引:19,自引:3,他引:16
We have recently isolated a cDNA encoding a novel human intracellular tyrosine kinase, termed RAFTK (for a related adhesion focal tyrosine kinase). The RAFTK cDNA, which encodes a polypeptide of 1,009 amino acids, shares 65% homology to the focal adhesion kinase (FAK), including several consensus motifs. In this report, we describe the biochemical characterization and functional analysis of the RAFTK protein. Coexpression of RAFTK and FAK proteins in megakaryocytic cells and blood platelets was observed. Using a specific antibody to RAFTK and the monoclonal antibody 2A7 to FAK, FAK and RAFTK could be distinguished antigenically. RAFTK had intrinsic tyrosine kinase and autokinase activities. It was phosphorylated on tyrosine in growing cultures of COS cells transfected with the pCDNAIII/flag-RAFTK expression vector containing the RAFTK cDNA ligated with the 8 amino acid flag peptide sequence. Similar to FAK, dephosphorylation of RAFTK was observed when adherent transfected COS cells were detached. Phosphorylation was regained upon replating of these cells on the fibronectincoated dishes. Analysis of tyrosine-phosphorylated RAFTK from adherent transfected COS cells showed that the Src homology 2 (SH2) domains of the Src and Fyn protein kinases as well as the Grb2 adaptor protein were able to specifically associate with RAFTK. Tyrosine phosphorylation of endogenous RAFTK was observed upon fibronectin-induced activation of human megakaryocytic cells. Furthermore, colocalization of RAFTK protein with vinculin, a focal adhesion protein, was observed by confocal microscopy in focal adhesion- like structures in adherent CMK cells and in transfected pCDNAIII/flag- RAFTK COS cells upon fibronectin activation. These data suggest that RAFTK is a novel member of the FAK family, that it localizes to focal adhesion-like structures in CMK megakaryocytic cells, that it participates in integrinmediated signaling pathways in megakaryocytes, and that it is able to associate with the tyrosine kinases Src and Fyn as well as the adaptor protein Grb2 via SH2-phosphotyrosine interactions. 相似文献
46.
Oligoclonal immunoglobulins in HIV infection 总被引:1,自引:0,他引:1
We tested 150 patients infected with human immunodeficiency virus (HIV) for the presence of oligoclonal bands in serum, prompted by reports that these abnormal proteins may have prognostic significance. Sixty HIV-negative individuals from "at-risk" groups were tested along with 80 HIV-negative, healthy blood donors for the presence of these bands. All sera were tested by isoelectric focusing, because it is more sensitive for this purpose than more-conventional electrophoretic techniques. In the HIV-positive group, 61% of the sera had oligoclonal bands; in the HIV-negative "at-risk" group, 36% had bands. No bands were detectable in sera from the healthy blood-donor group. Some patients were also followed for differing periods throughout their infection, and changes in their oligoclonal banding patterns could not be correlated with disease progression. The fact that oligoclonal bands were found to be present without HIV infection in a substantial number of individuals from within the "at-risk" groups leads us to conclude that the presence of oligoclonal bands in HIV infection is of limited prognostic significance. 相似文献
47.
Daniel J. Wallace MD Associate Clinical Professor of Medicine 《Seminars in arthritis and rheumatism》1989,18(4):282-296
Atabrine has been available for nearly 60 years. It has a variety of actions and has been administered to millions of individuals. Its antirheumatic properties have been well documented but have not been exploited optimally for a variety of reasons. The drug is generally quite safe and could be used in low doses in lupus and rheumatoid arthritis patients as a steroid-sparing agent or synergistically with hydroxychloroquine. Its bothersome side effects should not deter the clinician from using it, because they are easy to deal with or prevent (Table 5). Future studies should attempt to better characterize the immunosuppressive actions of this powerful drug, particularly in the treatment of lupus erythematosus and rheumatoid arthritis. Studies of the role of combination or single-agent antimalarial therapy in combination with other "remittive" drugs could be of great potential benefit. 相似文献
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Bell CJ Wallace JL 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1997,7(4):273-284
Infiltration of leucocytes into the mucosa is a hallmark feature of a number of inflammatory bowel disorders, most notably Crohn's disease and ulcerative colitis. The interactions between circulating leucocytes and the vascular endothelium that permit leucocyte migration to a site of injury or infection are mediated via a variety of adhesion molecules. There is now ample evidence for alterations in adhesion molecule expression and function in inflammatory bowel disorders. This raises the possibility that adhesion molecules could be targets for novel therapies. Indeed, many existing anti-inflammatory drugs are capable of modulating adhesion molecule expression or function. Moreover, intensive research is under way to develop more selective and effective modulators of adhesion molecules, in the hope that they will be useful for treating various inflammatory disorders. 相似文献