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免疫性血小板减少症(immune thrombocytopenia,ITP)是一种因免疫系统介导的血小板破坏过多进而导致血小板减少的疾病,具有高出血风险。冠心病(coronary artery disease,CAD)和经皮冠状动脉介入(percutaneous coronary intervention,PCI)术后的患者需要常规抗血小板治疗,与ITP的治疗相矛盾。本文报道1例ITP合并急性冠脉综合征(acute coronary syndrome,ACS)行PCI术的老年男性,因血小板数量低下、出血风险高而未行充分抗血小板治疗,导致ACS数次发作,于原冠脉支架内形成血栓,病程中数次行PCI术并调整抗血小板治疗方案和激素治疗剂量,以期为这类患者的临床处理提供参考。  相似文献   
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Ibrutinib inhibits Bruton tyrosine kinase (BTK), a key component of early B‐cell receptor (BCR) signalling pathways. A multicentre phase 2 trial of ibrutinib in patients with relapsed/refractory mantle cell lymphoma (MCL) demonstrated a remarkable response rate. However, approximately one‐third of patients have primary resistance to the drug while other patients appear to lose response and develop secondary resistance. Understanding the molecular mechanisms underlying ibrutinib sensitivity is of paramount importance. In this study, we investigated cell lines and primary MCL cells that display differential sensitivity to ibrutinib. We found that the primary cells display a higher BTK activity than normal B cells and MCL cells show differential sensitivity to BTK inhibition. Genetic knockdown of BTK inhibits the growth, survival and proliferation of ibrutinib‐sensitive but not resistant MCL cell lines, suggesting that ibrutinib acts through BTK to produce its anti‐tumour activities. Interestingly, inhibition of ERK1/2 and AKT, but not BTK phosphorylation per se, correlates well with cellular response to BTK inhibition in cell lines as well as in primary tumours. Our study suggests that, to prevent primary resistance or to overcome secondary resistance to BTK inhibition, a combinatory strategy that targets multiple components or multiple pathways may represent the most effective approach.  相似文献   
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BackgroundContrast-induced acute kidney injury is an adverse outcome resulting from radiocontrast medium exposure during coronary angiography and percutaneous coronary intervention.MethodsA systematic search was conducted to retrieve studies that investigated the impact of statin exposure before coronary angiography or percutaneous coronary intervention on the development of contrast-induced acute kidney injury. The primary outcome was the development of contrast-induced acute kidney injury. We separately analyzed statin/placebo comparisons and high-/low-dose statin comparisons.ResultsFifteen randomized controlled trials met inclusion criteria: 11 studies with statin-naïve subjects, 2 studies with chronic statin users, and 2 studies with unspecified prior statin exposure. Statin exposure reduced the risk of contrast-induced acute kidney injury relative to placebo (relative risk [RR] 0.63, P = .01) with a nonsignificant reduction in the need for hemodialysis (RR 0.25, P = .08). This benefit was also observed in high-dose versus low-dose statin trials (RR 0.46, P = .004), in statin-naïve patients (RR 0.53, P <.0001), and with all studied statins. Higher statin exposure reduced contrast-induced acute kidney injury in patients with acute coronary syndromes compared with placebo or low-dose statins (RR 0.49, P <.00001), with no significant benefit among patients undergoing elective procedures (RR 0.86, P = .50). Subgroup analyses confirmed the benefit of statins in patients with diabetes, chronic kidney disease, congestive heart failure, and those receiving >140 mL of contrast dye.ConclusionStatin therapy is effective at reducing the risk of contrast-induced acute kidney injury. It should thus be considered, at least on a short-term basis, for patients at increased risk of this complication.  相似文献   
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目的 探讨泮托拉唑钠肠溶胶囊联合吉法酯片对经皮冠状动脉介入治疗(PCI)术后双联抗血小板药物治疗的患者上消化道出血的预防作用。方法 选取2014年10月-2017年10月在西电集团医院行PCI的患者121例作为研究对象,按照入院先后顺序分为两组。对照组在术后第1天开始口服吉法酯片,100 mg/次,3次/d。观察组在对照组的基础上联合泮托拉唑钠肠溶胶囊,40 mg/d。比较两组患者术后6个月内上消化道出血的发生率、心血管不良事件、消化道不良反应和血小板聚集率。结果 术后6个月观察组患者的上消化道出血发生率显著低于对照组(P<0.05);心血管不良事件发生率两组比较无统计学差异,观察组消化道不良反应发生率显著低于对照组(P<0.05)。两组患者治疗前后的血小板聚集率相比无统计学差异。结论 泮托拉唑钠肠溶胶囊联合吉法酯片对PCI术后双联抗血小板药物治疗患者上消化道出血具有较好的预防作用,且显著降低消化道不良反应发生率,不增加心血管不良事件发生率,值得临床应用。  相似文献   
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Introduction

The estrogen antagonist tamoxifen (TAM) increases the thrombotic risk similar to estrogen containing oral contraceptives (OC). In OC users this risk is attributed to alterations of hemostasis resulting in acquired resistance to activated protein C (APC). TAM-induced APC resistance has not been reported yet.

Materials and Methods

Blood samples were collected prospectively from women with breast cancer before (n = 25) and monthly after start of adjuvant TAM treatment (n = 75). APC resistance was evaluated on basis of the effect of APC on the endogenous thrombin generation potential. To detect increased in vivo APC generation APC plasma levels were measured using a highly sensitive oligonucleotide-based enzyme capture assay. Routine hemostasis parameters were measured additionally.

Results

APC sensitivity decreased by 41% (p = 0.001) compared to baseline after one month of TAM application and remained significantly decreased during the study period. Free protein S increased (p = 0.008) while other analyzed procoagulant factors, inhibitors, and activation markers of coagulation decreased or did not change significantly. In five patients the APC concentration increased to non-physiological levels but an overall significant increase of APC was not observed.

Conclusions

This is the first study showing acquired APC resistance under TAM therapy. Acquired APC resistance might explain the increased thrombotic risk during TAM treatment. Observed changes of hemostasis parameters suggest different determinants of TAM-induced APC resistance than in OC-induced APC resistance. The presence of acquired APC resistance in TAM patients warrants further evaluation if these patients may benefit from antithrombotic prophylaxis in the presence of additional thrombotic risk factors.  相似文献   
90.
Background/AimsTo assess the factors causing delay in attaining DTB time of <90 min.MethodsEighty-five patients who underwent primary PCI from August 2008 to July 2009 were studied. From door-to-balloon, time was divided into 6 stages; any reason for delay was studied.ResultsThe mean DTB time was 80.5 min (SD = 34.4, median time 75 min, range 30–195). DTB time was <90 min in 76.5%, and DTB time >90 min occurred in 23.5%. Mean door to ECG – 6.5 min (SD = 2.7), mean time for the decision of PCI – 7.5 min (SD = 10.5), mean time taken for the patient's consent – 19.6 min (SD = 17.6), for STEMI team activation – 6.7 min (SD = 7.6), average time for financial process – 39.2 min (SD = 22.9). Average time for sheath to balloon – 5.2 min (SD = 1.7). Hospital related delay occurred in 5%, patient related delay in 80%, both together in 15%. 89.5% of patient related delay was due to delay in giving consent and financial reasons. There was no statistically significant delay for patients presented at morning or night and during the weekdays or weekend. Total mortality was 4.7%. Mortality among <90 min was 3.1%, mortality among >90 min was 10% (‘p’ = 0.2).ConclusionsWith effective hospital strategies, the DTB time of 90 min can be achieved in majority of patients. The chief delay in DTB time in this study was due to a delay in obtaining consent and financial reasons.  相似文献   
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