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951.
采用响应面优化法对超声波辅助法同步提取川芎精油(LCEO)和多糖(LCP)工艺条件进行优化,以总还原力和DPPH·清除率为指标评价LCEO和LCP的抗氧化活性.结果表明,川芎精油和多糖提取的最佳工艺条件为:液料比16mL/g,超声时间17 min,提取时间4.3 h,在此条件下,精油提取率为1.35%,多糖提取率为2....  相似文献   
952.
Background Rhizoctonia solani is a pathogenic fungus that causes serious diseases in many crops, including rice, wheat, and soybeans. In crop production, it is very important to understand the pathogenicity of this fungus, which is still elusive. It might be helpful to comprehensively understand its genomic information using different genome annotation strategies.MethodsAiming to improve the genome annotation of R. solani, we performed a proteogenomic study based on the existing data. Based on our study, a total of 1060 newly identified genes, 36 revised genes, 139 single amino acid variants (SAAVs), 8 alternative splicing genes, and diverse post-translational modifications (PTMs) events were identified in R. solani AG3. Further functional annotation on these 1060 newly identified genes was performed through homology analysis with its 5 closest relative fungi.ResultsBased on this, 2 novel candidate pathogenic genes, which might be associated with pathogen-host interaction, were discovered. In addition, in order to increase the reliability and novelty of the newly identified genes in R. solani AG3, 1060 newly identified genes were compared with the newly published available R. solani genome sequences of AG1, AG2, AG4, AG5, AG6, and AG8. There are 490 homologous sequences. We combined the proteogenomic results with the genome alignment results and finally identified 570 novel genes in R. solani.ConclusionThese findings extended R. solani genome annotation and provided a wealth of resources for research on R. solani.  相似文献   
953.
综合性医院重症监护病房病原菌分离情况分析   总被引:1,自引:0,他引:1  
目的探讨重症监护病房(Icu)医院内感染的临床特点及病原菌种类、分布情况,为临床合理使用抗菌药物、预防和控制医院感染提供参考和依据。方法采用前瞻性监测与回顾性调查相结合的方法,对ICU患者的临床资料进行统计分析。结果ICU病人标本中分离出病原菌593株,得出菌种分布与感染情况。结论重症监护病房医院内感染发生率高,以呼吸道感染为主,主要病原菌以革兰阴性非发酵菌为主,加强ICU患者感染的控制,可减少ICU医院内感染的发生。  相似文献   
954.
Acinetobacter baumannii poses a serious threat to human health, mainly because of its widespread distribution and severe drug resistance. However, no licensed vaccines exist for this pathogen. In this study, we created a conjugate vaccine against A. baumannii by introducing an O-linked glycosylation system into the host strain. After demonstrating the ability of the vaccine to elicit Th1 and Th2 immune responses and observing its good safety in mouse a model, the strong in vitro bactericidal activity and prophylactic effects of the conjugate vaccine against infection were further demonstrated by evaluating post-infection tissue bacterial loads, observing suppressed serum pro-inflammatory cytokine levels. Additionally, the broad protection from the vaccine was further proved via lethal challenge with A. baumannii. Overall, these results indicated that the conjugate vaccine could elicit an efficient immune response and provide good protection against A. baumannii infection in murine sepsis models. Thus, the conjugate vaccine can be considered as a promising candidate vaccine for preventing A. baumannii infection.  相似文献   
955.
The aim of this study was to investigate the effects of forkhead box protein P3 (FOXP3) intron single nucleotide variants (SNVs) in high‐risk human papilloma virus (HR‐HPV) infection and cervical cancer (CC) malignant lesions. We performed FOXP3 genotyping in 350 patients with CC and 350 healthy controls using the ImLDR multiple single nucleotide polymorphism genotyping technology. The heterozygous mutation TC in rs2294021 decreased the risk of HR‐HPV infection and CC malignant lesions (TC vs. TT: OR = 0.71, 95% CI = 0.51–0.99); the dominant model TC+CC and allele C in rs2294021 decreased the risk of CC malignant lesions (TC+CC vs. TT: OR = 0.69, 95% CI = 0.50–0.95; C vs. T: OR = 0.78, 95% CI = 0.63–0.97). The heterozygous mutation GA, dominant model GA+AA and allele A in rs3761549 also decreased the risk of HR‐HPV infection and CC malignant lesions (GA vs. GG: OR = 0.70, 95% CI = 0.51–0.96; GA+AA vs. GG: OR = 0.69, 95% CI = 0.51–0.94; A vs. G: OR = 0.75, 95% CI = 0.58–0.96). Patients with CC and HR‐HPV infection carrying rs2294021 TC and rs3761549 GA had lower expression of FOXP3 protein. Haplotype analysis revealed that T‐C‐A decreased the risk of HR‐HPV infection. Furthermore, we found a significant association between immune cells infiltration and prognosis in patients with CC. Our findings demonstrated that rs2294021 and rs3761549 variants may protect against HR‐HPV and CC malignant lesions by downregulating FOXP3 and that FOXP3 was associated with immune cells infiltration, which affected the prognosis of CC.  相似文献   
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957.
Alzheimer’s disease (AD) is the prevalent cause of dementia in the ageing world population. Apolipoprotein E4 (ApoE4) allele is the key genetic risk factor for AD, although the mechanisms linking ApoE4 with neurocognitive impairments and aberrant metabolism remains to be fully characterised. We discovered a significant increase in the ApoE4 content of serum exosomes in old healthy subjects and AD patients carrying ApoE4 allele as compared with healthy adults. Elevated exosomal ApoE4 demonstrated significant inverse correlation with serum level of thyroid hormones and cognitive function. We analysed effects of ApoE4-containing peripheral exosomes on neural cells and neurological outputs in aged or thyroidectomised young mice. Ageing-associated hypothyroidism as well as acute thyroidectomy augmented transport of liver-derived ApoE4 reach exosomes into the brain, where ApoE4 activated nucleotide-binding oligomerisation domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome by increasing cholesterol level in neural cells. This, in turn, affected cognition, locomotion and mood. Our study reveals pathological potential of exosomes-mediated relocation of ApoE4 from the periphery to the brain, this process can represent potential therapeutic target.Subject terms: Cognitive neuroscience, Alzheimer''s disease, Cellular neuroscience  相似文献   
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960.
鸭绿江香鱼耳石日轮与生长的研究   总被引:13,自引:0,他引:13  
1992年对鸭绿江香鱼耳石日轮与生长进行了研究。人工受精卵胚胎发育后期和前仔鱼期连续剖察表明,受精后约96小时胚体听囊内出现一对矢耳石,孵出后第2天耳石上出现第一个日轮,之后每天形成一轮。在光镜和扫描电镜下测定了幼、成鱼矢耳石的形态、直径、日轮数及其间距变化。耳石短径(v, μm)与鱼体长(x, mm)呈线性关系, 75尾幼、成鱼的关系式为y=3.28x+248.30。以耳石日轮数推算其产卵孵化期与实地调查结果一致。耳石日轮数(D)可用孵化后日数(N)减1表示。日轮间距有规律性变化,与鱼体生长发育和生态条件密切有关。依据日龄和相关体长体重资料进行了香鱼生长特性研究,用生长方程描绘的生长速度曲线和生长拐点(位于283日龄)等均较客观地反映了其生长特点。  相似文献   
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