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1.
Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) in particulate matter that has a diameter of ≤2.5 μm (PM2.5). Studies have demonstrated that BaP exposure causes oocyte meiotic arrest in mice. However, whether BaP exposure also affects oocyte maturation in offspring remains unclear. To test this, female mice were administered BaP before pregnancy to generate BaP-exposed offspring. Our findings showed that BaP exposure reduced the in vitro maturation and increased the abnormalities of meiotic apparatus in offspring oocytes. In addition, BaP exposure reduced the mitochondrial content and intracellular ATP generation, induced early apoptosis, increased reactive oxidative species accumulation and the genomic DNA 5-methylcytosine (5mc) level in offspring oocytes. Along with the abovementioned defective parameters, maternal BaP exposure further compromised the embryo developmental competence of offspring oocytes. In summary, our study demonstrated that maternal BaP exposure compromised offspring oocyte maturation and quality. 相似文献
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目的探讨舒芬太尼在肾母细胞瘤患儿术后镇痛中的应用效果及对患儿免疫功能的影响。方法采用随机数字表法将42例肾母细胞瘤患儿分为低剂量、中剂量和高剂量组,每组14例,低剂量组、中剂量组、高剂量组患儿术后舒芬太尼镇痛剂量分别为1.0、2.5、4.0μg/kg。术后6、24、48 h,采用中文版儿童疼痛行为量表(FLACC)评估三组患儿的镇痛效果,以及不良反应发生情况;麻醉前和术后1、24、72 h,检测三组患儿免疫功能指标,包括免疫球蛋白(Ig)G、IgA、IgM。结果术后6、24、48 h,中剂量组、高剂量组患儿FLACC评分均低于低剂量组患儿,差异均有统计学意义(P﹤0.05)。术后1、24、72 h,低剂量组患儿IgG、IgA、IgM水平均低于本组麻醉前,差异均有统计学意义(P﹤0.05);术后1、24 h,中剂量组和高剂量组患儿IgG、IgA、IgM水平均低于本组麻醉前,差异均有统计学意义(P﹤0.05),但术后72 h,中剂量组和高剂量组患儿IgG、IgA、IgM水平与麻醉前比较,差异均无统计学意义(P﹥0.05)。低剂量组患儿未发生不良反应,中剂量组患儿发生恶心1例,高剂量组患儿发生恶心5例、呕吐3例。结论2.5μg/kg的舒芬太尼在肾母细胞瘤患儿术后镇痛中效果明显,且对患儿的免疫系统发挥一定的保护作用,可以减轻患儿术后免疫功能抑制。 相似文献
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目的探讨维生素D(VitD)联合鱼油对糖尿病前期(PDM)患者糖脂代谢、胰岛β细胞功能的影响。 方法选取PDM患者132例,随机均分为联合组(VitD+鱼油)、VitD组(VitD)和对照组(不干预)。比较各组糖脂代谢、胰岛β细胞功能、炎症反应、血管内皮功能等指标。 结果与干预前比较,干预后联合组甘油三酯降低,白细胞介素-10增高(P<0.05),联合组和VitD组低密度脂蛋白胆固醇、肿瘤坏死因子-α、胰岛素抵抗指数、前列腺素E2、瘦素、抵抗素降低(P<0.05),空腹胰岛素、胰岛β细胞功能指数、脂联素增高(P<0.05),且联合组改善更为明显(P<0.05)。 结论维生素D联合鱼油治疗PDM患者可改善其脂代谢和胰岛功能相关指标,具有一定临床应用价值。 相似文献
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《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
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Angela Mauro Salvatore Mauro Roberto Rega Luigi Martemucci Rita Sottile 《Pediatric dermatology》2019,36(1):e34-e36
Henoch‐Schonlein purpura (HSP) is the most common systemic vasculitis in childhood. There is no consensus about the management for isolated cutaneous manifestations in HSP. We describe a case of HSP presenting with severe skin lesions that did not respond to standard therapy with corticosteroids. The 11‐year‐old child was treated with intravenous immunoglobulins, which induced rapid and persistent resolution of symptomatology. 相似文献
8.
《Vaccine》2021,39(26):3498-3508
Adenovirus infections are a major cause of epidemic keratoconjunctivitis (EKC), which can lead to corneal subepithelial infiltrates and multifocal corneal opacity. In the current study, we investigated the use of an E1/E3-deleted adenovirus serotype 5 (Ad5) vector as a vaccine administered intramuscularly (IM) or intranasally (IN) against subsequent challenges with a luciferase-expressing Ad5 (Ad5-Luci) vector via eyedrop. We evaluated the adaptive immune response to Ad5 vector vaccination and confirmed a robust polyfunctional CD8 T cell response in splenic cells. Neutralizing Ad5 antibodies were also measured in the sera of vaccinated mice as well as Ad5 antibody in the eye wash solutions. Upon challenge with Ad5-Luci vector 8 weeks post the primary immunization, transduction was significantly reduced by > 70% in the vaccinated mice, which was slightly better in IM- vs. that in IN-vaccinated animals. Resistance to subsequent challenge was observed 10 months post primary IM vaccination, with sustained reduction up to 60% in the Ad5-Luci vector transduction. Passive immunization of naive mice with antisera from IM to vaccinated mice subsequently challenged with the Ad5-Luci vector resulted in approximately 40% loss in transduction efficiency. Furthermore, the mice that received IM immunization with or without CD8 T cell depletion showed > 40% and 70% reductions, respectively, in Ad8 genomic copies after Ad8 topical challenge. We conclude that Ad-vector vaccination successfully induced an adaptive immune response that prevented subsequent Ad transduction in the cornea and conjunctiva-associated tissues in a mouse model of adenovirus keratoconjunctivitis, and that both cellular and humoral immunity play an important role in preventing Ad transduction. 相似文献
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《Burns : journal of the International Society for Burn Injuries》2021,47(8):1896-1907
Acute pain is prevalent following burn injury and can often transition to chronic pain. Prolonged acute pain is an important risk factor for chronic pain and there is little preclinical research to address this problem. Using a mouse model of second-degree burn, we investigated whether pre-existing stress influences pain(sensitivity) after a burn injury. We introduced a contribution of stress in two different ways: (1) the use of foot-shock as a pre-injury stressor or (2) the use of A/J mice to represent higher pre-existing stress compared to C57Bl/6 mice. C57Bl/6 and A/J mice were exposed to repeated mild foot shock to induce stress for 10 continuous days and mice underwent either burn injury or sham burn injury of the plantar surface of the right hind paw. Assessments of mechanical and thermal sensitivities of the injured and uninjured paw were conducted during the shock protocol and at intervals up to 82-day post-burn injury. In both strains of mice that underwent burn injury, thermal hypersensitivity and mechanical allodynia appeared rapidly in the ipsilateral paw. Mice that were stressed took much longer to recover their hind paw mechanical thresholds to baseline compared to non-stressed mice in both burn and non-burn groups. Analysis of the two mouse strains revealed that the recovery of mechanical thresholds in A/J mice which display higher levels of baseline anxiety was shorter than C57Bl/6 mice. No differences were observed regarding thermal sensitivities between strains. Our results support the view that stress exposure prior to burn injury affects mechanical and thermal thresholds and may be relevant to as a risk factor for the transition from acute to chronic pain. Finally, genetic differences may play a key role in modality-specific recovery following burn injury. 相似文献
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目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。 相似文献