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41.
BACKGROUND Peutz-Jeghers syndrome(PJS) is a rare autosomal dominant disorder, and female patients may develop gynecologic tumours. The prognosis for such patients is poor and the specific pathogenesis remains uncertain. Therefore, there are currently no uniform treatment options.CASE SUMMARY Herein, we introduce the case of a 45-year-old female who was diagnosed with PJS for 45 years and cervical cancer for 3 years. Postoperative pathological examination showed metastases in the right external i...  相似文献   
42.
To evaluate the cost–utility of pembrolizumab versus chemotherapy as the first-line setting for metastatic nonsmall cell lung cancer (NSCLC) from the US health care system perspective, a Markov model was developed to compare the lifetime cost and effectiveness of pembrolizumab versus chemotherapy for untreated metastatic NSCLC, based on the clinical data derived from phase III randomized controlled trial (KEYNOTE- 042; ClinicalTrials.gov; NCT02220894). Weibull distribution was fitted to simulate the parametric survival functions. Drug costs were collected from official websites, and utility values were obtained from published literature. Total costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) were computed as primary output indicators. The impact of different PD-L1 expression levels on ICER was also evaluated. One-way and probabilistic sensitivity analyses were performed to assess the model uncertainty. Compared with chemotherapy, patients treated with pembrolizumab provided an additional 1.13, 1.01, and 0.59 QALYs in patients with PD-L1 expression levels of ≥50%, ≥20%, and ≥1%, with corresponding incremental cost of $53,784, $47,479, and $39,827, respectively. The resultant ICERs of pembrolizumab versus chemotherapy were $47,596, $47,184, and $68,061/QALY, in three expression levels of PD-L1, respectively, all of which did not exceed the WTP threshold of 180,000/QALY. Probability sensitivity analysis outcome supported that pembrolizumab exhibited evident advantage over chemotherapy to be cost-effective. One-way sensitivity analysis found that ICERs were most sensitive to utility value of pembrolizumab in progression survival state. All the adjustment of parameters did not qualitatively change the result. For treatment-naive, metastatic NSCLC patients with PD-L1+, pembrolizumab was estimated to be cost-effective compared with chemotherapy for all PD-L1 expression levels at a WTP threshold of $180,000/QALY in the context of the US health care system.  相似文献   
43.
目的探讨协同刺激分子程序性死亡受体1(PD-1)及程序性死亡受体配体1(PD-L1)在人脑胶质瘤中的表达及其临床意义。方法收集2013年1月至2017年12月长治医学院附属和济医院70例脑胶质瘤术后蜡块标本及35例正常脑组织蜡块标本。采用免疫组织化学SP法检测PD-1、PD-L1在胶质瘤组织及正常脑组织中的表达。分析两者表达与患者临床病理特征之间的关系以及PD-1、PD-L1两者在胶质瘤组织中表达的相关性。结果PD-1、PD-L1在胶质瘤组织中的阳性表达率分别为69%(48/70)、62%(43/70),均高于其在正常脑组织中的阳性表达率[29%(10/35)、31%(11/35)],差异均有统计学意义(χ2值分别为15.099、8.407,均P<0.05)。高级别胶质瘤中PD-1、PD-L1的阳性表达率分别为81%(30/37)、73%(27/37),均高于低级别胶质瘤中的阳性表达率[55%(18/33)、49%(16/33)],差异均有统计学意义(χ2值分别为5.699、4.415,均P<0.05)。不同性别、年龄、肿瘤最大径分层患者间PD-1、PD-L1阳性表达率差异均无统计学意义(均P>0.05)。胶质瘤组织中PD-1与PD-L1蛋白的表达呈正相关(r=0.372,P=0.002)。结论PD-1、PD-L1可能在胶质瘤的发生、发展过程中相互作用,有望成为评估胶质瘤发生、发展的生物学新指标。  相似文献   
44.
45.
近年来免疫检查点抑制剂(immune checkpoint inhibitor,ICI)陆续获批用于多种恶性肿瘤的治疗,为患者带来新的希望。但在一些瘤种中ICI单药客观缓解率仅10%~20%,如何提高临床获益是免疫相关临床研究关注的重点。近期研究显示,联合不同机制的ICI有助于提高缓解率和发挥持久的抗肿瘤作用,合适的剂量方案也能合理平衡疗效和安全性。拟对ICI联合治疗的机制、药代动力学和临床研究进展进行综述。  相似文献   
46.
《Clinical lung cancer》2020,21(5):e405-e414
BackgroundProgrammed cell death 1 (PD-1) inhibitors have become a standard treatment, albeit not completely effective, for patients with advanced non–small-cell lung cancer (NSCLC). Previous studies of advanced melanoma have revealed that the tumor burden predicted the response to PD-1 inhibitors, although this relationship has remained unclear for NSCLC.Patients and MethodsThe present single-center retrospective study evaluated 163 patients with advanced NSCLC who had received PD-1/programmed cell death ligand 1 (PD-L1) inhibitor monotherapy from December 2015 to December 2018. The clinical tumor burden was estimated using the baseline sum of the target lesions’ longest diameters (BSLDs), measured according to the Response Evaluation Criteria for Solid Tumors, and the baseline number of metastatic lesions (BNMLs).ResultsThe optimal cutoff values for predicting progression-free survival (PFS) were 5 for the BNMLs and 76 mm for the BSLDs, using the minimum P value method. The low-BNML group included 73 patients (44.8%). The median PFS was 12.2 months in the low-BNML group and 2.8 months in the high-BNML group (hazard ratio, 0.51; P = .0005). The low-BSLD group included 92 patients (56.4%). The median PFS was 9.6 months in the low-BSLD group and 3.4 months in the high-BSLD group (hazard ratio, 0.52; P = .0006). Multivariable analysis revealed that low-BSLD, low-BNML, nonsquamous histologic type and a PD-L1 tumor proportion score of ≥ 50% were independently associated with prolonged PFS.ConclusionsPD-L1 expression and the clinical tumor burden can predict the efficacy of PD-1/PD-L1 inhibitor monotherapy for NSCLC.  相似文献   
47.
目的 比较不同脉冲间隔时间下程控硬膜外间歇脉冲注入(PIEB)模式和持续恒速输注(CEI)模式用于分娩镇痛的临床效果。方法 选择单胎妊娠、头位、足月初产妇95例,年龄20~40岁,ASAⅡ或Ⅲ级,孕期37~41周,随机分为三组:传统CEI模式组(C组,n=31)、PIEB模式间隔时间60 min组(P60组,n=32)和PIEB模式间隔时间40 min组(P40组,n=32)。在宫口扩张至1~4 cm时,采用硬膜外阻滞行分娩镇痛,注射负荷量后15 min为产妇镇痛开始时间。C组于镇痛开始后立即开启CEI模式,持续以10 ml/h恒速输注。P60组于镇痛开始后60 min开启PIEB模式,单次脉冲10 ml,脉冲间隔时间60 min。P40组于镇痛开始后40 min开启PIEB模式,单次脉冲10 ml,脉冲间隔时间40 min。镇痛泵配方为0.075%罗哌卡因+0.5μg/ml舒芬太尼100 ml,单次按压量5 ml,锁定时间15 min。记录镇痛前(t0)、镇痛后1 h(t1)、镇痛后2 h(t2)、宫口开全(t  相似文献   
48.
目的研究自身免疫性肝炎患者外周血CD8+T淋巴细胞程序性死亡受体1(PD-1)表达的变化。方法选择自身免疫性肝炎患者22例和健康人20例,使用流式细胞仪检测所有被研究者外周血CD8+T淋巴细胞PD-1分子的表达状况,比较不同分期和不同性别疾病患者PD-1表达水平。结果自身免疫性肝炎患者外周血CD8+T淋巴细胞PD-1分子阳性百分比为2.5±0.5%,显著高于健康对照组(0.5±0.1%,P<0.001);自身免疫性肝炎发病期患者CD8+T淋巴细胞表达PD-1百分比为2.6±0.7%,与缓解期比无统计学差异(3.4±0.8%);16例女性AIH患者外周血CD8+T淋巴细胞PD-1阳性百分比为3.5±0.7%,亦略高于6例男性患者的1.3±0.3%,但无显著统计学差异(P=0.1021),可能与例数较少有关。结论自身免疫性肝炎患者CD8+T淋巴细胞PD-1表达率增加,PD-1可能在自身免疫性肝炎的发病中起了重要作用。  相似文献   
49.
目的研究HBV转基因小鼠肝脏中NKT细胞的功能与表面PD1、CD28表达的关系。方法分离小鼠肝脏、脾脏、胸腺和腹膜淋巴结单个核细胞,利用流式细胞检测技术,分别检测其淋巴细胞中NKT细胞的频率,同时检测肝脏NKT细胞PD1、CD28的表达及IFN-γ、IL-4的分泌功能,比较肝脏、脾脏、胸腺和腹膜淋巴结这几个主要免疫组织淋巴细胞中NKT细胞所占的比例,并分析肝脏NKT细胞PD1、CD28的表达与细胞功能的关系。结果与正常同品系小鼠比较,HBV转基因小鼠肝脏、脾脏、胸腺和腹膜淋巴结NKT细胞数量明显减少(P<0.05),与脾脏、胸腺和腹膜淋巴结相比,肝脏淋巴细胞中含有大量的NKT细胞;与正常同品系小鼠比较,HBV转基因小鼠肝脏NKT细胞PD1的表达明显增多(P<0.05),CD28的表达明显减少(P<0.05),肝脏NKT细胞IFN-γ、IL-4的分泌功能明显降低(P<0.05)。结论肝脏中含有大量的NKT细胞,HBV转基因小鼠肝脏NKT细胞的功能存在明显的缺陷,并提示PD1的增加和CD28的降低可能与NKT细胞功能的下调密切相关。  相似文献   
50.
The immune system is responsible for defending the host from a large variety of potential pathogens, while simultaneously avoiding immune reactivity towards self-components. Self-tolerance has to be tightly maintained throughout several central and peripheral processes; immune checkpoints are imperative for regulating the immunity/tolerance balance. Dendritic cells (DCs) are specialized cells that capture antigens, and either activate or inhibit antigen-specific T cells. Therefore, they play a key role at inducing and maintaining immune tolerance. DCs that suppress the immune response have been called tolerogenic dendritic cells (tolDCs). Given their potential as a therapy to prevent transplant rejection and autoimmune damage, several strategies are under development to generate tolDCs, in order to avoid activation and expansion of self-reactive T cells. In this article, we summarize the current knowledge relative to the main features of tolDCs, their mechanisms of action and their therapeutic use for autoimmune diseases. Based on the literature reviewed, autologous antigen-specific tolDCs might constitute a promising strategy to suppress autoreactive T cells and reduce detrimental inflammatory processes.  相似文献   
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