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1.
《HPB : the official journal of the International Hepato Pancreato Biliary Association》2022,24(5):681-690
BackgroundThe American Joint Committee on Cancer (AJCC) made improvements for staging pancreatic neuroendocrine tumors (pNETs) in its 8th Edition; however, multicenter studies were not included.MethodsWe collected multicenter datasets (n = 1,086, between 2004 and 2018) to validate the value of AJCC 8 and other coexisting staging systems through univariate and multivariate analysis for well-differentiated (G1/G2) pNETs.ResultsCompared to other coexisting staging systems, AJCC 7 only included 12 (1.1%) patients with stage III tumors. Patients with European Neuroendocrine Tumor Society (ENETS) stage IIB disease had a higher risk of death than patients with stage IIIA (hazard ratio [HR]: 4.376 vs. 4.322). For the modified ENETS staging system, patients with stage IIB disease had a higher risk of death than patients with stage III (HR: 6.078 vs. 5.341). According to AJCC 8, the proportions of patients with stage I, II, III, and IV were 25.7%, 40.3%, 23.6%, and 10.4%, respectively. As the stage advanced, the median survival time decreased (NA, 144.7, 100.8, 72.0 months, respectively), and the risk of death increased (HR: II = 3.145, III = 5.925, and IV = 8.762).ConclusionThese findings suggest that AJCC 8 had a more reasonable proportional distribution and the risk of death was better correlated with disease stage. 相似文献
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Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl2-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl2 treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl2, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl2-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca2+-CaMKII-dependent Akt/mTOR pathway. 相似文献
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《Journal of thoracic oncology》2020,15(1):91-100
IntroductionClinical studies have shown that a combination of a tyrosine kinase inhibitor (TKI) and pemetrexed overcame acquired resistance to epidermal growth factor receptor (EGFR) TKI in NSCLC. Previously, pemetrexed+gefintib (P+G) had improved progression-free survival (PFS) compared with gefitinib. We present OS, updated PFS, biomarker analysis, and safety of P+G versus gefitinib.MethodsThis was a phase 2, multicenter, randomized study conducted in East Asian patients with advanced nonsquamous NSCLC with EGFR mutations. Patients were randomized (2:1) to receive P+G (500 mg/m2 intravenously 3-weekly + 250 mg/day orally) or gefitinib.ResultsIn total, 191 patients (P+G, n=126; gefitinib, n=65) comprised the intent-to-treat and safety populations. Median OS was 43.4 months in P+G versus 36.8 months in gefitinib arm; adjusted HR 0.77 (95% CI, 0.5-1.2); one-sided P=0.105. Median PFS was significantly longer in the P+G (16.2 months) versus gefitinib arm (11.1 months); adjusted HR 0.67 (95% CI, 0.5-0.9); one-sided P=0.009. In the P+G and gefitinib arms, median PFS was 22.6 and 11.0 months, respectively, in patients with low thymidylate synthase (TS) expression, and 12.6 and 9.9 months, respectively, in patients with high TS expression. Common second-line post-discontinuation systemic therapies were EGFR-TKIs and chemotherapy. Most patients experienced at least one adverse event.ConclusionsAddition of pemetrexed to EGFR TKI gefitinib resulted in significantly improved PFS and numerically longer OS compared with gefitinib in treatment-naïve patients with EGFR-mutated advanced nonsquamous NSCLC. Low TS expression appeared to be a good predictor for treatment outcomes. 相似文献
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目的探讨低能体外冲击波(ESW)和低剂量间歇人重组甲状旁腺素1-34(rhPTH1-34)对体外培养大鼠成骨细胞(ROBs)增殖和成骨分化的影响。方法分别用不同次数的低能ESW刺激、不同浓度及作用方式的rhPTH1-34刺激,以及ESW和低剂量间歇性rhPTH1-34刺激共同作用于ROBs后,用细胞计数、MTY和流式细胞术细胞周期分析检测ROBs的增殖,用酶标仪检测ALP活性,用免疫组化检测I型胶原表达来观察ROBs成骨分化。结果60~150次0.18mJ/mm^2 ESW刺激、间歇性rhPTH1-34(1×10^-11和1×10^-10 mol/L)刺激以及ESW+间歇性rhPTH1-34(1×10^-11mol/L)刺激均可显著促进体外培养ROBs细胞增殖和成骨分化(与对照组比较,P〈0.05);其中60~150次ESW刺激+间歇性rhPTH1-34(1×10^-11 mol/L)刺激各组作用最强。结论适当的ESW应力刺激和低剂量间歇性rhPTH1-34刺激可显著促进体外培养ROBs细胞增殖和成骨分化,两者联合应用作用最强。 相似文献
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中下段颈椎的应力松弛特性及前、后路手术对其的影响 总被引:3,自引:1,他引:2
目的 研究中下段颈椎的应力松弛特性,并评估椎间盘切除植骨术与椎板切开术对其影响。方法 6例新鲜尸体完整颈椎及手术后颈椎,在模拟生理状态下进行屈曲及伸展位的应力松弛实验。结果 在恒应变条件下,绘制术前及不同术式后的中下段颈椎的应力松弛函数及曲线;术后的中下段颈椎的应力和初始化应力比值G(t)比术前明显增大,前路椎间盘切除植骨术后的G(t)值比椎板切开术大,两者均有统计学意义。结论 在恒应变条件下,颈椎具有快速应力松弛敏感性,屈曲位比伸展位大。椎板成形术及颈椎前路椎间盘切除植骨术都使颈椎的应力松弛能力减弱,前路椎间盘切除植骨术的影响更大。 相似文献
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高效液相色谱法测定复方万年青胶囊中大黄素 总被引:1,自引:0,他引:1
目的建立复方万年青胶囊中大黄素的含量测定方法。方法采用高效液相色谱(HPLC)法,以Diamonsil C18(4.6 mm×250 mm×5μm)为分析柱,甲醇-0.1%磷酸溶液(80∶20)为流动相,流速为1.0 ml/min,柱温为35℃,检测波长254 nm。结果大黄素在0.039~0.355μg范围内呈良好线性关系,r=1.0000。平均回收率为99.3%,RSD=0.4%(n=5)。结论HPLC法是一种简便、准确、可靠的分析方法。 相似文献