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991.
992.
EGFR mutation testing in non-small cell lung cancer (NSCLC) is a novel and important molecular pathological diagnostic assay that is predictive of response to anti-epidermal growth factor receptor (EGFR) therapy. A comprehensive compilation of a large number of EGFR mutation analyses of the German Panel for Mutation Analyses in NSCLC demonstrates (a) a higher than previously reported mutation frequency outside the conventionally tested exons 19 and 21 and (b) an overall superiority of sequencing based assays over mutation-specific PCR. The implications for future diagnostic EGFR mutation testing are discussed.  相似文献   
993.
An oxygen-sensitive and highly unstable L -serine dehydratase was partially purified from the Grampositive anaerobe Clostridium sticklandii. The final active preparation contained five proteins of 27, 30, 44.5, 46, and 58 kDa as judged by SDS-PAGE. The N-terminal sequence of the 30 kDa subunit showed some similarity to the α-subunits of the iron-containing L -serine dehydratases from Clostridium propionicum and Peptostreptococcus asaccharolyticus. Oxygen-inactivated L -serine dehydratase from C. sticklandii was reactivated by incubation with Fe2+ under reducing conditions. Furthermore, the enzyme was inactivated by iron-chelating substances like phenanthroline and EDTA. Pyridoxal-5-phosphate (PLP) did not stimulate the activity, and known inhibitors of PLP-containing enzymes such as NaBH4 had no effect on the activity of L -serine dehydratase from C. sticklandii.  相似文献   
994.
ObjectivesTo systematize the scientific knowledge of empirically tested strategies for verbally providing medical information in patient-physician consultations.MethodsA scoping review searching for terms related to physician, information, oral communication, and controlled study. Four pairs of reviewers screened articles. For each selected study, we assessed the quality and summarized aspects on participants, study, intervention, and outcomes. Information provision strategies were inductively classified by types and main categories.ResultsAfter screening 9422 articles, 39 were included. The methodological quality was moderate. We identified four differently used categories of strategies for providing information: cognitive aid (n = 13), persuasive (n = 8), relationship- (n = 3), and objectivity-oriented strategies (n = 4); plus, one “mixed” category (n = 11). Strategies were rarely theoretically derived.ConclusionsCurrent research of tested strategies for verbally providing medical information is marked by great heterogeneity in methods and outcomes, and lack of theory-driven approaches. The list of strategies could be used to analyse real life communication.Practice implicationsFindings may aid the harmonization of future efforts to develop empirically-based information provision strategies to be used in clinical and teaching settings.  相似文献   
995.
Obesity is frequently associated with a chronic low-grade inflammation in the adipose tissue (AT) and impaired glucose homeostasis. Adipose tissue macrophages (ATMs) have been shown to accumulate in the inflamed AT either by means of recruitment from the blood or local proliferation. ATM proliferation and activation can be stimulated by TH2 cytokines, such as IL-4 and IL-13, suggesting involvement of CD4-positive T cells in ATM proliferation and activation. Furthermore, several studies have associated T cells to alterations in glucose metabolism. Therefore, we sought to examine a direct impact of CD4-positive T cells on ATM activation, ATM proliferation and glucose homeostasis using an in vivo depletion model. Surprisingly, CD4 depletion did not affect ATM activation, ATM proliferation, or insulin sensitivity. However, CD4 depletion led to a significant improvement of glucose tolerance. In line with this, we found moderate disturbances in pancreatic endocrine function following CD4 depletion. Hence, our data suggest that the effect on glucose metabolism observed after CD4 depletion might be mediated by organs other than AT and independent of AT inflammation.  相似文献   
996.
We assessed c-MET expression and oncogene amplification in a cohort enrolling 92 surgically treated penile squamous cell carcinomas (PSCCs). A tissue microarray was constructed for c-MET immunohistochemistry (IHC) and chromogenic silver in situ hybridization (SISH). Two independent pathologists evaluated IHC by employing the breast cancer scoring rules, and scored the presence of MET oncogene amplification and/or polysomy-7. Eighty study cases (87%) showed c-MET expression. No study case had MET oncogene amplification, but 42 patients (45.7%) had polysomy-7. Polysomy-7 showed a significant positive correlation with c-MET expression (ρ = 0.323, p = 0.002). Neither c-MET expression nor polysomy-7 was associated with histopathologic parameters or with cancer-specific survival (median post-surgical follow-up 32 months). Our data suggest that the majority of PSCCs exhibit c-MET expression which is not associated with oncogene amplification, but might be attributable to polysomy-7. Further studies should investigate the expression and activation of downstream molecules functionally involved in c-MET pathway signaling, and clarify the so far unresolved role of c-MET inhibitors as potential targeted therapies in PSCCs with metastatic dissemination.  相似文献   
997.
Multiple myeloma management has undergone profound changes in the past thanks to advances in our understanding of the disease biology and improvements in treatment and supportive care approaches. This article presents recommendations of the European Myeloma Network for newly diagnosed patients based on the GRADE system for level of evidence. All patients with symptomatic disease should undergo risk stratification to classify patients for International Staging System stage (level of evidence: 1A) and for cytogenetically defined high- versus standard-risk groups (2B). Novel-agent-based induction and up-front autologous stem cell transplantation in medically fit patients remains the standard of care (1A). Induction therapy should include a triple combination of bortezomib, with either adriamycin or thalidomide and dexamethasone (1A), or with cyclophosphamide and dexamethasone (2B). Currently, allogeneic stem cell transplantation may be considered for young patients with high-risk disease and preferably in the context of a clinical trial (2B). Thalidomide (1B) or lenalidomide (1A) maintenance increases progression-free survival and possibly overall survival (2B). Bortezomib-based regimens are a valuable consolidation option, especially for patients who failed excellent response after autologous stem cell transplantation (2A). Bortezomib-melphalan-prednisone or melphalan-prednisone-thalidomide are the standards of care for transplant-ineligible patients (1A). Melphalan-prednisone-lenalidomide with lenalidomide maintenance increases progression-free survival, but overall survival data are needed. New data from the phase III study (MM-020/IFM 07-01) of lenalidomide-low-dose dexamethasone reached its primary end point of a statistically significant improvement in progression-free survival as compared to melphalan-prednisone-thalidomide and provides further evidence for the efficacy of lenalidomide-low-dose dexamethasone in transplant-ineligible patients (2B).  相似文献   
998.
BACKGROUND AND METHODS: 5-Iodo-2'-deoxyuridine (IdUrd) radiolabelled with the positron emitter I or with the gamma and Auger electron emitters I or I has been proposed for cancer diagnosis and therapy. We modified the synthesis to reliably obtain [I]IdUrd and [I]IdUrd by using an Iodogen supported destannylation reaction of 5-(tri-n-butylstannyl)-2'-deoxyuridine (Bu3SndUrd) which meets the requirements for good laboratory practice (GLP) and good clinical practice (GCP). A method of purification was developed to eliminate by-products as well as any unreacted starting material. RESULTS: [I]IdUrd, which originated from a trace of iodide in the Bu3SndUrd precursor, was identified as the unknown by-product reported for this method. This trace could be eliminated by modified purification of Bu3SndUrd. Stabilization of pH was essential for unequivocal identification of radiolabelled IdUrd and possible degradation products in the different systems tested for quality control. Biodistribution in tumour bearing nude mice was measured as early as 3 and 6 h after i.v. injection of [I]IdUrd. This compound showed high and specific activity uptake in tumour and dividing tissues when combined with 5-fluoro-2'-deoxyuridine pre-treatment. Uptake was specifically inhibited by injection of excess thymidine.  相似文献   
999.
Retinal glial (Müller) cells may play a major role in vascular eye diseases as they secrete vascular endothelial growth factor (VEGF), a hypoxia-induced angiogenic cytokine. They also release significant amounts of the anti-angiogenic factors, transforming growth factor (TGF)-beta2, pigment epithelium derived factor (PEDF), and thrombospondin-1 (TSP-1). Exposure of human (MIO-M1) and guinea-pig Müller cells to hypoxia resulted in a decreased release of TGF-beta2 and PEDF but in an elevated secretion of TSP-1. When retinal endothelial cells were exposed to VEGF/anti-angiogenic factor ratios mimicking those found in culture media of Müller cells under normoxia or hypoxia, their proliferation was significantly inhibited by TGF-beta2, PEDF or TSP-1. Thus Müller cells may provide a permanent anti-proliferative condition for retinal endothelial cells.  相似文献   
1000.
Clopidogrel is an effective and specific inhibitor of ADP-induced platelet aggregation. After metabolic activation, the active clopidogrel metabolite irreversibly impairs the human platelet P2Y12 ADP receptor. Gialpha-protein activation and inhibition of vasodilator-stimulated phosphoprotein (VASP) phosphorylation are two key elements of the P2Y12 receptor pathway suitable for quantitation of clopidogrel effects. So far, only limited data exist about a diminished responsiveness to clopidogrel and underlying possible mechanisms. We investigated clopidogrel effects in 57 patients after percutaneous coronary intervention and stent implantation by flow cytometry for the analysis of intracellular VASP phosphorylation. Patients were treated with a 300 mg clopidogrel loading dose, followed by 75 mg/day clopidogrel in combination with 100 mg/day aspirin. Samples were drawn after a median of 5 days of clopidogrel treatment. Considerable differences in the responsiveness to clopidogrel could be observed and it was shown that 17.5% (10/57) of the patients revealed an inadequate responsiveness to clopidogrel despite continuation of clopidogrel intake. Comparable amounts of Gialpha and VASP were found in two clopidogrel low-responding patients as well as in two responding patients. To exclude a molecular defect of P2Y12 ADP receptor, the P2Y12 receptor gene of eight clopidogrel treated patients (seven patients with inadequate responsiveness, one responder) was sequenced. We only found a single silent mutation in exon 2 at position 1828 (GA). We suggest that individual differences in clopidogrel metabolization could cause relevant variations in clopidogrel responsiveness despite the use of a 300 mg clopidogrel loading dose.  相似文献   
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