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排序方式: 共有548条查询结果,搜索用时 15 毫秒
1.
参照GenBank中牛支原体脂蛋白P48基因序列,设计并合成特异性引物Mb-F/Mb-R,建立了牛支原体PCR检测方法,并在扩增条件优化的基础上,对该方法的特异性和灵敏度进行了分析,进而应用建立的方法完成了疑似牛支原体肺炎临床病料的检测。结果显示,建立的PCR方法对牛支原体的核酸样品能扩增出534 bp的特异性目的片段,而对无乳支原体、丝状支原体、大肠杆菌、绿脓杆菌、链球菌、多杀性巴氏杆菌、金黄色葡萄球菌、沙门菌、肺炎克雷伯氏菌、黏质沙雷氏菌、变形杆菌等牛常见条件病原微生物核酸样品均未见明显的扩增条带,且其可检测出的牛支原体DNA最低浓度约为0.000 002 875μg/mL。对临床样品的检测结果显示,该方法的检出率与与病原分离的符合率为100%。上述结果表明,本研究成功建立了牛支原体PCR检测方法,可用于临床上牛支原体肺炎的快速诊断。  相似文献   
2.
Lophophora is a member of the Cactaceae family, which contains two species: Lophophora williamsii and L. diffusa. Lophophora williamsii is an illegal plant containing mescaline, a hallucinogenic alkaloid. In this study, a novel method based on a single nucleotide polymorphism (SNP) assay was developed for identifying L. williamsii; this assay reliably detects SNPs within chloroplast DNA (rbcL, matK, and trnL-trnF IGS) and was validated for identifying Lophophora and L. williamsii simultaneously. The chloroplast DNA sequences from four L. williamsii and three L. diffusa plants were obtained and compared using DNA sequence data from approximately 300 other Cactaceae species available in GenBank. From this sequence data, a total of seven SNPs were determined to be suitable for identifying L. williamsii. A multiplex assay was constructed using the ABI PRISM® SNaPshot™ Multiplex Kit (Applied Biosystems, Forster City, CA) to analyze species-specific SNPs. Using this multiplex assay, we clearly distinguished the Lophophora among 19 species in the Cactaceae family. Additionally, L. williamsii was distinguished from L. diffusa. These results suggest that the newly developed assay may help resolve crimes related to illegal distribution and use. This multiplex assay will be useful for the genetic identification of L. williamsii and can complement conventional methods of detecting mescaline.  相似文献   
3.
为建立检测非洲猪瘟病毒(African swine fever virus,ASFV)的快速诊断方法,本研究根据ASFV SY18株p17蛋白的编码基因D117L的保守序列设计并合成引物和探针,建立了基于ASFV p17蛋白的编码基因D117L的TaqMan荧光定量PCR检测方法,并验证其特异性、灵敏性和重复性。结果显示,本研究建立的TaqMan荧光定量PCR检测方法的C_t值与标准品在1×10^9~1×10^1copies/μL范围内呈良好的线性关系,相关系数为0.998,斜率为-3.192,检测下限为10 copies/μL,且与其他能引起相似症状的猪源病毒无交叉反应。重复性试验结果显示,组间与组内变异系数均小于1.920 7%,重复性好。此方法可用于ASF的早期诊断和ASFV快速检测。  相似文献   
4.
The onus of proof in criminal cases is beyond any reasonable doubt, and the issue on the lack of complete internal validation data can be manipulated when it comes to justifying the validity and reliability of the X-chromosomal short tandem repeats analysis for court representation. Therefore, this research evaluated the efficiency of the optimized 60% reduced volumes for polymerase chain reaction (PCR) amplification using the Qiagen Investigator® Argus X-12 QS Kit, as well as the capillary electrophoresis (CE) sample preparation for blood samples on Flinder's Technology Associates (FTA) cards. Good-quality DNA profile (3000–12,000 RFU) from the purified blood sample on FTA card (1.2 mm) were obtained using the optimized PCR (10.0 μL of PCR reaction volume and 21 cycles) and CE (9.0 μL Hi-Di™ Formamide and 0.3 μL DNA Size Standard 550 [BTO] and 27 s injection time) conditions. The analytical and stochastic thresholds were 100 and 200 RFU, respectively. Hence, the internal validation data supported the use of the optimized 60% reduced PCR amplification reaction volume of the Qiagen Investigator® Argus X-12 QS Kit as well as the CE sample preparation for producing reliable DNA profiles that comply with the quality assurance standards for forensic DNA testing laboratories, while optimizing the analytical cost.  相似文献   
5.
为了检测牛传染性鼻气管炎病毒,本研究建立了牛传染性鼻气管炎病毒SYBR Green I实时荧光定量PCR检测方法。通过设计特异性引物扩增病毒基因,将扩增的目的片段(119 bp)连接到pMD19-T载体中,构建重组质粒。将重组质粒作为阳性标准品,用于SYBR Green I实时荧光定量PCR检测方法的建立。结果显示,特异性引物扩增的目的片段约为119 bp,符合预期的大小,经测序鉴定所扩增的目的片段正确。敏感性结果显示,用该方法检测阳性质粒标准品的最低限度为3.04 X101 copies/mL,是Nano-PCR的10倍。将牛病毒性腹泻病毒、牛呼吸道合胞体病毒、牛副流感病毒3型与牛传染性鼻气管炎病毒进行特异性检测。结果显示,只有牛传染性鼻气管炎病毒被检测到,其他病毒均未有特异性的扩增曲线,表明该方法的特异性良好。批内和批间重复变异系数均小于1%,显示该方法具有良好的重复性。用建立的方法对20份疑似IBRV的临床样品进行检测,并与Nano-PCR检测方法进行对比,结果显示本方法的阳性样晶率高于Nano-PCR检测方法。本研究建立的牛传染性鼻气管炎病毒SYBR Green I实时荧光定量PCR方法特异性好、灵敏度高、重复性好,可用于牛传染性鼻气管炎病毒的检测。  相似文献   
6.
《Science & justice》2020,60(4):388-397
The Quantiplex® Pro RGQ kit quantifies DNA in a sample, supports the detection of mixtures and assesses the extent of DNA degradation based on relative ratios of amplified autosomal and male markers. Data show no significant difference in the accuracy and sensitivity of quantification between this and the Promega PowerQuant® System, both detecting the lowest amount of DNA tested, 4 pg. Laboratory controlled mixed male:female DNA samples together with mock sexual assault samples were quantified across a range of mixture ratios. Analysis software detected mixed DNA samples across all ratios for both quantification kits. Subsequent STR analysis using the Investigator® 24Plex QS Kit was able to corroborate mixture detection down to 1:25 male:female DNA ratios, past which point mixtures appeared identical to single-source female samples. Analysis software also detected laboratory degraded DNA samples, with data showing a positive trend between the Degradation Index (DI) and length of time of sonication. When used on ancient remains the assay was able to triage samples for further analysis, and STR profiles were concordant with DNA quantification results in all instances. STR analyses of laboratory-controlled sensitivity, mixture, and degradation studies supports the quality metric obtained from quantification. These data support the use of the Quantiplex® Pro RGQ kit for sample screening and quantification in forensic casework and ancient DNA studies.  相似文献   
7.
In this cross-sectional study of substance users in Norway, the authors describe the patterns of victimization and investigate the factors associated with victimization, for nonoffenders and offenders separately. Recent victimization was reported by 59%, and the victimization rate was higher among offenders compared with nonoffenders (69% and 43%, p < .001). Women, regardless of offender status, experienced more victimization. Unstable housing was associated with victimization among nonoffenders, whereas markers for more severe substance use and indicators for poor mental health were associated with victimization in both groups. Addressing these factors may be important in reducing victimization and its negative outcomes among substance users.  相似文献   
8.
以法院庭审为界限,庭审之前的准备程序称为刑事审判前程序,庭审之后的程序,称为刑事审判后程序。这样划分的目的,是为了更好地对辩护律师开庭前后的诉讼活动进行区分。应将辩护律师在休庭后择日宣判、一审判决送达后到上诉程序启动前以及死刑复核等阶段的诉讼活动纳入到刑事审判后程序中,作为一个整体来思考,探究这一程序中辩护律师介入的立法缺陷、具体路径以及实践操作等层面的问题。  相似文献   
9.
Agroecology has played a key role in helping Cuba survive the crisis caused by the collapse of the socialist bloc in Europe and the tightening of the US trade embargo. Cuban peasants have been able to boost food production without scarce and expensive imported agricultural chemicals by first substituting more ecological inputs for the no longer available imports, and then by making a transition to more agroecologically integrated and diverse farming systems. This was possible not so much because appropriate alternatives were made available, but rather because of the Campesino-a-Campesino (CAC) social process methodology that the National Association of Small Farmers (ANAP) used to build a grassroots agroecology movement. This paper was produced in a ‘self-study’ process spearheaded by ANAP and La Via Campesina, the international agrarian movement of which ANAP is a member. In it we document and analyze the history of the Campesino-to-Campesino Agroecology Movement (MACAC), and the significantly increased contribution of peasants to national food production in Cuba that was brought about, at least in part, due to this movement. Our key findings are (i) the spread of agroecology was rapid and successful largely due to the social process methodology and social movement dynamics, (ii) farming practices evolved over time and contributed to significantly increased relative and absolute production by the peasant sector, and (iii) those practices resulted in additional benefits including resilience to climate change.  相似文献   
10.
采用资金型REITs发展模式的美国,经过近50年的发展已经成为全球最成熟的市场.本文在对我国房地产金融市场和初期REITs过程存在问题进行探讨的基础上,分析美国REITs成长性的成功原因,并探讨有利于我国REITs可持续发展的外延式扩张模式.  相似文献   
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