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1.
目的 研究黄芪-丹参对动脉粥样硬化(atherosclerosis,AS)大鼠肠道菌群的影响。方法 将大鼠随机分为空白组、模型组、辛伐他汀组(1 mg/kg)、黄芪-丹参组(0.75 g/kg),采用高脂饲料喂养联合腹腔注射维生素D3 8周的方法复制AS模型,同时灌胃给药。采用自动生化分析仪检测大鼠血清总胆固醇(total cholesterol, TC)、三酰甘油(Triacylglycerol, TG)、低密度脂蛋白胆固醇(low-density lipoprotein cholesterol, LDL-C)水平,采用酶联免疫吸附试验检测血清肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-6(interleukin-6,IL-6)、白细胞介素-1β(interleukin-1β,IL-1β)水平,光学显微镜下观察胸主动脉病理变化,采用生物信息分析方法观察大鼠结肠内容物肠道菌群变化。结果 与空白组比较,模型组大鼠血清TC、TG、LDL-C、TNF-α、IL-6、IL-1β水平明显升高(P<0.05),HDL-C水平明显降低(P<0.05),胸主动脉血管内皮损伤严重,可见明显蓝色钙状斑块,结肠内容物肠道菌群Berger-Parker、Simpson指数明显降低(P<0.05),放线菌门(Actinobacteria)、乳杆菌属(Lactobacillus)、双歧杆菌属(Bifidobacterium)和杜氏杆菌属(Dubosiella)群落丰度明显降低(P<0.05),变形菌门(Proteobacteria)、疣微菌门(Verrucomicrobia)以及布劳特氏菌属(Blautia)、unclassified_f_Ruminococcaceae和Lachnospiraceae_NK4A136_group群落丰度明显升高(P<0.05)。与模型组比较,黄芪-丹参组大鼠血清血脂和炎症因子水平明显改善(P<0.05),胸主动脉血管内皮无明显损伤及增厚,大致恢复正常,结肠内容物肠道菌群Berger-Parker、Simpson指数明显升高(P<0.05),放线菌门、乳杆菌属、双歧杆菌属和杜氏杆菌属群落丰度明显升高(P<0.05),变形菌门、疣微菌门以及布劳特氏菌属、unclassified_f_Ruminococcaceae和Lachnospiraceae_NK4A136_group群落丰度明显降低(P<0.05)。〖JP〗结论 黄芪-丹参治疗AS的作用机制可能是通过调控肠道菌群改善血脂代谢和抑制炎症水平实现的。  相似文献   
2.
This study aimed at identifying the frequency of kit-dependent discordances and genetic specialties in STR DNA typing, which is particularly important for the interpretation of DNA profiles as well as national and international database searches. We analyzed a total of 27′510 buccal swabs with the PowerPlex ESI 17 and NGM SElect amplification kits and documented discordances and other anomalies. We found kit-dependent full dropouts to be the most frequent events, most of which were associated with the NGM SElect kit. The total kit-dependent discordance rate determined in this study amounts to 0.74%. With this dataset, we also provide dropout rates, which can be used to estimate silent allele frequencies for 16 common STR loci amplified with the PowerPlex ESI17 and NGM SElect amplification kits.  相似文献   
3.
Abstract

There are debates on the relevance of Eurocentric normative frameworks for studying the media in post-colonial Africa. Emerging from these debates is a rebuttal of the dominant Western-derived paradigms for the conceptualisation of journalistic norms, values and practices. Given that the dominant Western liberal models for normative media ethics are incongruent to the needs of Africa, there is a growing call to reconceptualise media ethics anchored upon alternative epistemologies and moral foundations such as ubuntuism. Although there is existing scholarship on ubuntuism as a framework for media ethics in Africa, none of these studies has focused particularly on Zimbabwe. Using the 16 August 2019 (hereafter August 16) protests as a photojournalistic “moment” as a frame, this article explores the views and perspectives of Zimbabwean journalists on their understanding of media ethics and professionalism. Further, it probes the possibilities of ubuntuism as a moral foundation of journalistic practice in the country. Journalists’ views are diverse and contested on the nature and practice of media ethics in the country. Although ubuntuism is touted as a normative framework for media ethics, the Western liberal perspectives remain dominant. As such, post-colonial theory offers a useful approach to understanding the interconnections, contradictions and tensions underpinning media ethics in post-colonial Zimbabwe.  相似文献   
4.
Soil analysis is a valuable resource in forensic investigation. Classical forensic soil analysis involves examination of its physical characteristics and chemical composition, such as soil type, colour, particle size, shape, pH, elemental, mineral and organic content. However the limited variability of these parameters is not always allowing adequate discrimination between soil samples. As soil supports extreme diversity of microorganisms and eukaryotic communities, microbiological approaches have been proposed. Several molecular approaches for microbial DNA profiling are available; however there is a lack of published data of implementation of the next generation sequencing (NGS) approaches for forensic soil analysis.The aim of the current study was elaboration of criteria for soil metagenome data management and database searching. We used our previously sequenced collection of 11 samples collected from different environments (forests, fields, grasslands, urban park) with different flora. The single sample collection includes 9 soil samples per one sampling area (30 m × 30 m) spaced by 15 m. In the current study we concentrated mainly on 18S rRNA gene V2-V3 region for fungi however SSU rRNA region for arbuscular mycorrhizal (AMF) fungi and V2-V3 hypervariable region of 16S rRNA gene for bacterial communities were taken into account. The sequencing was performed by Roche/454 platform. For data analysis OTU based approach on mothur software and NCBI BLASTN search were used. NCBI BLASTN analysis revealed altogether 2983 AMF matches and 8997 18S matches as well as 25477 OTUs (16S) were determined. Several data filtration approaches were used for data management. We found that 18S marker results could be used to create and run a filtered database that is computationally much more efficient and flexible. Our results have broad impact; however more samples have to be analysed, additional studies performed and cooperation between soil scientists and forensic scientists is required to be able to implement these novel techniques into the routine forensic practice.  相似文献   
5.
Abstract: The quality and efficiency of a standard organic DNA isolation method and a silica‐based method using the QIAGEN Blood Maxi Kit were compared to obtain human DNA and short tandem repeats (STRs) profiles from 39 exhumed bone samples for paternity testing. DNA samples were quantified by real‐time PCR, and STR profiles were obtained using the AmpFlSTR® Identifiler® PCR amplification kit. Overall, the silica‐based method recovered less DNA ranging from 0 to 147.7 ng/g (average 7.57 ng/g, median = 1.3 ng/g) than did the organic method ranging from 0 to 605 ng/g (average 44.27 ng/g, median = 5.8 ng/g). Complete profiles (16/16 loci tested) were obtained from 37/39 samples (95%) using the organic method and from 9/39 samples (23%) with the silica‐based method. Compared with a standard organic DNA isolation method, our results indicate that the published silica‐based method does not improve neither the quality nor the quantity of DNA for STR profiling.  相似文献   
6.
四川某猪场暴发保育猪与育肥猪水样腹泻,病理剖解可见胃黏膜大面积脱落、胃溃疡等症状,采集病死猪扁桃体与肠系膜淋巴结进行病毒检测;以肠内容物做寄生虫卵检测;选取其中一代表病例做细菌分离,经小鼠致死试验、仔猪回归试验确定病原菌,并对病原菌进行了形态学观察、生化鉴定、16SrDNA序列分析及药敏试验。结果显示,猪瘟病毒、伪狂犬病病毒等的检测结果为阴性;无寄生虫感染;从十二指肠内容物中分离到1株疑似致病性大肠杆菌,并命名为SCDC-1。用SCDC-1株人工感染健康仔猪成功复制出水样腹泻、胃溃疡病例。对SCDC-1株进行16SrDNA克隆测序,并与GenBank中的8株肠杆菌科和4株巴氏杆菌科菌株的16S基因进行同源性分析,发现SCDC-1株与大肠杆菌16S基因的相似性高达99.5%~99.9%。药敏试验结果显示,该病原菌仅对头孢曲松钠、头孢吡肟、丁胺卡那霉素敏感。试验结果证实,引起此次保育猪与育肥猪胃溃疡的主要病原为致病性大肠杆菌。  相似文献   
7.
Abstract

Most of the literature on state transformation focuses on China’s relations with African, Asian and Latin American countries and the National Oil Companies’ overseas expansion to show that China has become fragmented, decentralised and internationalised. This article contributes novel findings by focusing on China’s relations with Europe and the actions of China’s National Nuclear Companies (NNCs). It shows that NNCs, which have become relatively autonomous actors, often pursue their agendas of expansion into Europe without much coordination with, or even in contradiction to, other ministries’ agendas and interests, especially the Ministry of Foreign Affairs. Instead of being orchestrated by the central government, their expansion reflects considerable disorganisation and sometimes undermines China’s official strategy. The article demonstrates this through case studies of NNCs’ involvement in the UK and Romania.  相似文献   
8.
目的应用mt DNA中COI(348bp)、COII(637bp)及16Sr DNA(513bp)基因序列鉴定贵阳地区常见尸食性蝇类的种属。方法收集贵阳地区常见尸食性蝇类标本,经形态学分类鉴定后提取胸肌DNA,扩增COI(348bp)、COII(637bp)及16Sr DNA(513bp)基因片段,测序后用DNAMAN 4.0序列分析软件进行序列拼接,NCBI中的BLAST、MEGA 5.2软件包对所得序列分析建立种内及种间进化分歧率,并构建系统发育树。结果 COI种间平均进化分歧率为12.55%,种间范围在3.0%~18.6%,种内范围在0%~0.7%;COII种间平均进化分歧率为13.73%,种间范围在5.3%~21.6%,种内范围在0%~0.6%;16Sr DNA种间平均进化分歧率为4.54%,种间范围在0.4%~7.6%,种内范围在0%~0.4%。结论 COI、COII及16Sr DNA可用于尸食性蝇类的种属鉴定,该方法可作为传统分类方法的补充手段。  相似文献   
9.
When a body is discovered in water, it is difficult to conclude whether the cause of death was drowning, even today. Although diatom testing by the digestive method is classical, we hypothesized that aquatic bacteria, as well as diatoms, might be detected in drowned bodies, and conducted temperature gradient gel electrophoresis (TGGE)‐targeting 16S rDNA. DNA was extracted from the site water, and from heart blood and liver samples from 27 bodies concluded as drowning deaths by autopsy and subjected to TGGE after amplification of 16S rDNA by polymerase chain reaction. We observed whether the feature point of each 16S rDNA from the site water and blood or liver samples matched. Considerably higher correspondence was observed in drowned bodies, and the rate was higher than that achieved with the digestive method. Moreover, TGGE is safer than the digestive method. Our study suggests that this method can aid diagnosis of drowning.  相似文献   
10.
On 26 July 2017, the Grand Chamber of the European Court of Justice rendered its seminal Opinion 1/15 about the agreement on Passenger Name Record data between the EU and Canada. The Grand Chamber considered that the decision of the Council about the conclusion, on behalf of the Union, of the agreement between the EU and Canada about the transfer and processing of PNR data must be based jointly on Article 16(2) about the protection of personal data and Article 87(2)(a) about police co-operation among member states in criminal matters, but not on Article 82(1)(d) about judicial co-operation in criminal matters in the EU of the Treaty on the Functioning of the EU. The Grand Chamber also considered that the agreement is incompatible with Article 7 on the right to respect for private life, Article 8 on the right to the protection of personal data, Article 21 on non-discrimination and Article 52(1) on the principle of proportionality of the Charter of Fundamental Rights of the EU since it does not preclude the transfer, use and retention of sensitive data. In addition to the requirement to exclude such data, the Grand Chamber listed seven requirements that the agreement must include, specify, limit or guarantee to be compatible with the Charter.The opinion of the Grand Chamber has far-reaching implications for the agreement on PNR data between the EU and Canada. It has also far-reaching implications for international agreements on PNR data between the EU and other third states. Last, it has far-reaching implications for Directive 681 of 27 April 2016 on PNR data.  相似文献   
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