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81.
Molecular determinants of cetuximab efficacy.   总被引:17,自引:0,他引:17  
PURPOSE: To investigate whether mRNA expression levels of cyclin D1 (CCND1), cyclooxygenase 2 (Cox-2), epidermal growth factor receptor (EGFR), interleukin 8 (IL-8), and vascular endothelial growth factor (VEGF), all members of the EGFR signaling pathway, are associated with clinical outcome in patients with EGFR-expressing metastatic colorectal cancer (CRC) treated with cetuximab. PATIENTS AND METHODS: Thirty-nine patients with metastatic CRC, refractory to both irinotecan and oxaliplatin, were enrolled on IMCL-0144 and treated with single-agent cetuximab. The intratumoral mRNA levels of CCND1, Cox-2, EGFR, IL-8, and VEGF were assessed from paraffin-embedded tissue samples using laser-capture microdissection and quantitative real-time polymerase chain reaction. RESULTS: There were 21 women and 18 men with a median age of 64 years (range, 35 to 83 years). Higher gene expression levels of VEGF were associated with resistance to cetuximab (P = .038; Kruskal-Wallis test). The combination of low gene expression levels of Cox-2, EGFR, and IL-8 was significantly associated with overall survival (13.5 v 2.3 months; P = .028; log-rank test). Both findings were independent of skin toxicity that was itself significantly correlated to survival. Patients with a lower mRNA amount of EGFR had a longer overall survival compared with patients that had a higher mRNA amount (7.3 v 2.2 months; P = .09; log-rank test). Patients with lower expression of Cox-2 had a significantly higher rate of grade 2 to 3 skin reactions under cetuximab treatment. CONCLUSION: This pilot study suggests that gene expression levels of Cox-2, EGFR, IL-8, and VEGF in patients with metastatic CRC may be useful markers of clinical outcome in single-agent cetuximab treatment.  相似文献   
82.
In addition to the rhodopsin crystal structure, high-resolution crystal structures of ligand-mediated G-protein-coupled receptors (GPCRs) have recently become available, and these have become attractive templates for developing homology models of several GPCRs of therapeutic interest. These crystal structures and the homology models derived from them have provided significant insights into ligand–receptor interactions. Moreover, several studies have demonstrated that the structural models are indeed suitable for virtual screening of compound databases to identify new ligands for various GPCRs. Recent examples of such virtual screening against GPCRs are discussed in this review.  相似文献   
83.

Background  

Bortezomib, a proteasome-specific inhibitor, has emerged as a promising cancer therapeutic agent. However, development of resistance to bortezomib may pose a challenge to effective anticancer therapy. Therefore, characterization of cellular mechanisms involved in bortezomib resistance and development of effective strategies to overcome this resistance represent important steps in the advancement of bortezomib-mediated cancer therapy.  相似文献   
84.
试析陆懋修从阳明论治温病之特色   总被引:1,自引:0,他引:1  
陆懋修(1818-1886),又名免研,字九芝,号江左下工,又号林屋山人,江苏元和(今江苏吴县)人,为清代后期著名的医学家。陆氏出身于官宦之家,儒医兼通,陆氏秉承家学,对先人的医学成就颇为敬重。他曾三十余年坚持潜心研究《内经》、《伤寒》等医学经典著作,终于贯通医理而成为一代名医。陆氏一生博览群书之余,著述不断,  相似文献   
85.
86.
陈晨  汪凯 《中国卒中杂志》2007,15(11):1239-1243
尼麦角林是一种麦角生物碱衍生物,广泛应用于脑血管病患者认知障碍的治疗。多项临
床前研究显示,尼麦角林对于认知障碍的改善可能与以下因素有关:尼麦角林除能够改善脑循环,
促进神经递质释放外,还具有营养神经及抗氧化等作用。目前的研究认为,尼麦角林能够改善患者
卒中后抑郁相关的情绪障碍以及有效改善血管性痴呆,提高患者的日常生活能力。同时,尼麦角林具
有良好的安全性,目前暂无尼麦角林治疗导致纤维化或麦角中毒的研究报道。本文就尼麦角林在神
经系统的作用机制、临床疗效及安全性进行综述,以期为临床应用提供参考。  相似文献   
87.
This study evaluated the safety and efficacy of batroxobin in treating hyperfibrinogenemia for secondary stroke prevention. Patients with ischemic stroke or transient ischemic attack (TIA) were measured for plasma fibrinogen levels. Selected participants had concomitant hyperfibrinogenemia (plasma fibrinogen > or = 3.0 g/l). Patients enrolled between 1 July 2003 and 31 December 2004 were treated with batroxobin; patients enrolled between 1 January 2002 and 30 June 2003 were treated without batroxobin. Batroxobin was administered intermittently via intravenous injection at 3-monthly intervals. Patients in both groups were followed for 1 year. Any cerebrovascular events and suspected adverse events were recorded. In total, 112 ischemic stroke/TIA patients with concomitant hyperfibrinogenemia were enrolled, 52 being treated with batroxobin and 60 without batroxobin. Six patients (11.5%) with batroxobin and 16 patients (26.7%) without batroxobin had recurrent cerebral ischemic events during follow-up. Stroke/TIA recurrence in patients without batroxobin was higher than that in patients with batroxobin (P < 0.05). Two patients with batroxobin and two patients without batroxobin developed hemorrhagic stroke during follow-up. There were five deaths (9.6%) in the batroxobin group, and seven deaths (11.7%) in the nonbatroxobin group during follow-up (P > 0.05). Intermittent intravenous injection of batroxobin can efficiently reduce the risk for stroke/TIA recurrence in patients with concomitant hyperfibrinogenemia.  相似文献   
88.
支架内血栓形成是支架置入术后的一种常见并发症。术后血管内皮损伤、胶原组织暴露和作为异物的支架均为引发血栓形成的可能机制。不能及时识别处理则成为再狭窄的重要原因。我们报告1例发生在大脑中动脉(middle cerebral artery,MCA)支架内的血栓形成,探讨其识别处理过程和可能的机制。  相似文献   
89.
90.
目的探讨臂丛加强化麻醉后颈部抽动的原因及防治。方法对近年来在麻醉方法、用药相同,术后颈部抽动患者的观察治疗过程进行分析。结果臂丛麻醉并发颈部抽动给予充分镇静后可完全治愈。结论麻醉后并发颈部抽动为药物副作用及颈局部刺激的综合作用。  相似文献   
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