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61.
Despite the presence of hepatitis B virus (HBV) in the human breastmilk of mothers infected with HBV, it has been shown that breastfeeding does not increase the risk of mother-to-child transmission (MTCT) of HBV. We tested the hypothesis that human breastmilk may contain active components that bind to HBV and inhibit the infectivity of HBV. The results show that human whey significantly inhibited the binding of the hepatitis B surface antigen (HBsAg) to its antibodies in competitive inhibition immunoassays. The far-western blotting showed that HBsAg bound to a protein of 80 kD in human whey, which was identified as lactoferrin by mass spectrometry. Competitive inhibition immunoassays further demonstrated that both human lactoferrin and bovine lactoferrin bound to HBsAg. Human whey, human lactoferrin, and bovine lactoferrin each significantly inhibited the infectivity of HBV in vitro. Our results indicate that human breastmilk can bind to HBsAg and inhibit the infectivity of HBV, and the active component is lactoferrin. The findings may explain the reason that breastfeeding has no additional risk for MTCT of HBV, although human breastmilk contains HBV. Our study provides experimental evidence that HBV-infected mothers should be encouraged to breastfeed their infants  相似文献   
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李冲  王钰  张文静  韩冰冰  张义敏 《中草药》2024,55(12):4235-4247
糖尿病周围神经病变(diabetic peripheral neuropathy,DPN)是指糖尿病患者出现周围神经功能障碍相关症状的慢性并发症,是足部溃疡、感染和截肢的高危因素。临床主要采用疼痛管理、控制血糖和营养神经的药物治疗,多产生耐药性和不良反应,治疗效果并不理想。研究发现黄芪桂枝五物汤(Huangqi Guizhi Wuwu Decoction,HGD)在防治DPN方面具有较好的效果,通过对HGD治疗DPN的药效基础、临床应用及相关作用机制进行综述,为HGD治疗DPN的进一步开发利用提供理论依据和参考。  相似文献   
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Background Substantial evidence indicates that dysbiosis of the gut microbial community is associated with colorectal neoplasia. This review aims to systematically summarise the microbial markers associated with colorectal neoplasia and to assess their predictive performance.Methods A comprehensive literature search of MEDLINE and EMBASE databases was performed to identify eligible studies. Observational studies exploring the associations between microbial biomarkers and colorectal neoplasia were included. We also included prediction studies that constructed models using microbial markers to predict CRC and adenomas. Risk of bias for included observational and prediction studies was assessed.Results Forty-five studies were included to assess the associations between microbial markers and colorectal neoplasia. Nine faecal microbiotas (i.e., Fusobacterium, Enterococcus, Porphyromonas, Salmonella, Pseudomonas, Peptostreptococcus, Actinomyces, Bifidobacterium and Roseburia), two oral pathogens (i.e., Treponema denticola and Prevotella intermedia) and serum antibody levels response to Streptococcus gallolyticus subspecies gallolyticus were found to be consistently associated with colorectal neoplasia. Thirty studies reported prediction models using microbial markers, and 83.3% of these models had acceptable-to-good discrimination (AUROC > 0.75). The results of predictive performance were promising, but most of the studies were limited to small number of cases (range: 9–485 cases) and lack of independent external validation (76.7%).Conclusions This review provides insight into the evidence supporting the association between different types of microbial species and their predictive value for colorectal neoplasia. Prediction models developed from case-control studies require further external validation in high-quality prospective studies. Further studies should assess the feasibility and impact of incorporating microbial biomarkers in CRC screening programme.Subject terms: Prognostic markers, Microbiome  相似文献   
65.
This study was focused on investigating the involvement of polyamine metabolism in the myocardial ischemia-reperfusion injury (MIRI) in an in vivo rat model. A branch of the descending left coronary artery was occluded for 30 min followed by 2 h, 6 h, 12 h, and 24 h reperfusion. Then the expression of spermidine/spermine N1-acetyltransferase (SSAT) and ornithine decarboxylase (ODC) and the concentrations of polyamines were assessed. It was found that the expression of SSAT and ODC were upregulated after reperfusion and the concentrations of spermidine and spermine were significantly decreased, while putrescine concentration was significantly increased. The results suggest that MIRI may cause disturbance of polyamine metabolism, and it may play a critical role in MIRI.  相似文献   
66.
The general preparation method for V2O5 is ammonium salt vanadium precipitation, which inevitably produces large amounts of ammonia nitrogen wastewater. In this paper, we propose an environmentally friendly method for preparing high-purity V2O5 with low ammonium consumption. The purity of the V2O5 product reaches more than 99% while reducing the level of ammonium consumption. The vanadium precipitation efficiency reaches 99.23% and the V2O5 purity of the product reaches 99.05% under the following conditions: precipitation time of 1.5 h, precipitation temperature of 98 °C, initial precipitation pH of 2, ammonium addition coefficient of 2, purification time of 5 min with purification performed twice, purification temperature of 65 °C. In this study, compared with the use of ammonia spirit for vanadium precipitation and ammonium salt vanadium precipitation, the ammonia consumption levels are reduced by 79.80% and 80.00%, and the purity levels are increased by 0.70% and 1.01%, respectively. The compositions of the precipitated (NaV3O8∙xH2O) and purified ((NH4)2V6O16·1.5H2O) hydrolysis products are characterized via XRD. The TGA results show that NaV3O8∙xH2O contains 1.5 times the amount of crystal water. The FTIR results explain that the two V3O8 layers are combined end-to-end to form a V6O162− layer. The change of the product image indicates that the purification process includes three stages. Firstly, heating and NH4+ attack expand the V3O8 layer. NH4+ diffuses more easily into the V3O8 layer. Secondly, NH4+ destroys the electrostatic interaction between Na+ with the V3O8 layer and replacing Na+. Finally, V3O8 is polymerized into V6O162− to keep the crystal structure stable.  相似文献   
67.
流式细胞分析技术(flow cytometry,FCM),又称流式细胞术,是一种在功能水平上对单细胞或其他生物粒子进行定量分析和分选的技术,具有广泛的科研应用价值.采用理论与实践并举,结合讨论的教学方式,在教师队伍开设针对性的培训课程,对深刻理解并在科研工作中有效利用该技术具有及其重要意义.同时以教学促科研,以科研促技...  相似文献   
68.
种植体-杆卡式附着体固位的覆盖全口义齿   总被引:8,自引:0,他引:8       下载免费PDF全文
目的:总结和评价种植体一杆卡式附着体在覆盖全口义齿中的应用经验和效果。方法:将种植体与杆式附着体结合,以粘膜支持式、混合支持式和种植体支持式3种设计形式,为46例患者制作种植式全口覆盖义齿,并检查义齿的固位力和稳定性;同时采用修复体测力仪对其中15例患者义齿的固位效果进行定量评价。结果:3种设计均可达到良好的固位效果,其中混合支持式和种植体支持式的稳定、支持效果更好;应用2 ̄3只尼龙卡可分别为覆盖  相似文献   
69.
无牙颌一侧上颌骨缺损种植修复后的有限元应力分析   总被引:2,自引:0,他引:2  
目的:探讨无牙颌一侧上颌骨缺损种植修复后在力作用下支持组织中的应力分布特点。方法:建立无牙颌一侧上颌骨缺损种植修复的三维有限元模型,观察计算机模拟的不同修复方式以及不同加载方式作用下骨组织中的应力分布情况。结果:无论何种加载方式,在单纯健侧种植修复时,1位种植体周围骨皮质应力值均很高;双侧种植修复后无论何种加载方式1位种植体周围骨皮质的应力值都大大降低。结论:患侧植入种植体能够降低单纯健侧种植时邻近缺损处的种植体周围骨皮质应力,使支持组织中应力分布均匀合理,提高修复成功率。  相似文献   
70.
目的:对临床最常见的半侧上颌骨缺损中不同种植修复设计进行比较研究,筛选出最优的临床设计方案。方法:建立无牙颌上颌骨种植修复三维有限元模型,进行应力分析。结果:获得无牙颌上有种植修复三维有限元模型,得到了各种应力条件下各种植体/骨界面应力值。结论:得到的最佳设计方案为:使用1只种植体,杆式支架过中线1cm,达到平衡He,可恢复部分患侧咬合功能。  相似文献   
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