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21.
Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
22.
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.  相似文献   
23.
Odontology - To investigate the characterization and function of a novel porous osteogenic material (PLLA / DDM) containing polylactic acid and demineralized dentin matrix. The surface morphology...  相似文献   
24.
癫痫发作后状态(PIS)是指癫痫发作停止到恢复至发病前水平的异常状态,包括认知、运动、感觉、自主神经和精神行为等异常,症状多样,严重程度不一,持续数秒至数天不等,对患者的健康和生活质量产生很大影响。然而,目前国内外相关的研究较少,临床医生对此缺乏正确认识,容易误诊误治。本文将从PIS的定义、病理生理机制、临床表现、诊断和鉴别诊断、临床意义以及干预策略等进行综述,以提高临床医生的认识,并为今后临床研究提供参考。  相似文献   
25.
孙莉  赵毅 《现代肿瘤医学》2019,(13):2420-2424
三阴性乳腺癌(triple negative breast cancer,TNBC)是雌激素受体(estrogen receptor,ER)、孕激素受体(progesterone receptor,PR)及人类表皮生长因子受体(human epidermal growth factor-2,HER-2)均不表达的乳腺癌。按其功能特征可归纳为5类分子分型:以DNA修复缺陷或生长因子为途径的基底细胞样三阴性乳腺癌;以上皮-间充质转化和肿瘤干细胞为特征的间质样三阴性乳腺癌;免疫调节型三阴性乳腺癌;雄激素受体过表达的管腔/分泌型三阴性乳腺癌;HER-2富集型三阴性乳腺癌。三阴性乳腺癌恶性程度高且异型性较大,其治疗困难且预后较差,内分泌治疗及靶向治疗不敏感。目前很多学者对于三阴性乳腺癌的治疗各有研究,并有临床试验证实下述治疗有效。  相似文献   
26.
目的:探索健脾生血片治疗慢性心力衰竭伴贫血的疗效、安全性和作用机制。方法:选取2016年5月至2017年2月同济医院收治的慢性心力衰竭贫血患者144例,按照随机数字表法分为观察组和对照组,每组72例。观察组给予健脾生血片治疗,3片/次,3次/d,疗程3个月;对照组给予生血宝合剂治疗,15 m L/次,3次/d,3个月为1个疗程。比较2组患者治疗前与治疗后血红蛋白、红细胞计数、网织红细胞、血清铁、转铁蛋白饱和度、血清铁蛋白、血清铁调素(Hepcidin)、血清IL-1β、血清肿瘤坏死因子-α(TNF-α)、血清C反应蛋白(CRP)、左室射血分数(LVEF)、6 min步行距离、明尼苏达心力衰竭生命质量量表(MLHFQ)和不良事件。并随访2组心血管事件次数,住院次数与全因死亡率。结果:观察组72例患者完成了前3个月的治疗,随访期间脱失2例;对照组治疗期间1例患者退出研究,随访期间脱失4例。2组一般资料比较,差异无统计学意义(P 0. 05),具有可比性。观察组贫血有效率98. 6%,对照组有效率11. 3%,差异有统计学意义(P0. 05)。治疗后观察组红细胞计数和网织红细胞、均显著高于对照组(P 0. 05)。观察组血清铁、转铁蛋白饱和度水平均高于对照组,差异有统计学意义(P 0. 05),但血清铁调素水平显著低于对照组,差异有统计学意义(P 0. 05),血清铁蛋白水平2组差异无统计学意义(P 0. 05)。观察组IL-1β、血清TNF-α、血清CRP均显著低于对照组,差异有统计学意义(P 0. 05)。观察组LVEF、6 min步行距离、明尼苏达心力衰竭生命质量量表(MLHFQ)均显著高于对照组,差异有统计学意义(P 0. 05)。2组不良事件总发生率比较,差异无统计学意义(P 0. 05),但对照组4例患者出现血清肌酐、尿素氮水平异常,发生率高于观察组,差异有统计学意义(P 0. 05)。经1年随访,观察组心血管事件人均发生次数显著少于对照组(P 0. 05),但2组住院次数和全因死亡率比较,差异无统计学意义(P 0. 05)。结论:健脾生血片可有效治疗心力衰竭伴贫血,减少心血管发生次数,并且安全性良好,其作用机制与提供准确足量铁元素、抑制铁调素表达,抑制慢性炎性反应有关。  相似文献   
27.
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.  相似文献   
28.
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
29.
30.
MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
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