17results about How to "Avoid False Positive Results" patented technology

The invention belongs to the technical field of biology, and relates to a pathogen detection technology based on a CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) system, in particular to a tubercle bacillus detection and activity determination method based on fluorescent T7-CRISPR. The first purpose is to provide a reagent combination for detecting viable tubercle bacillus, and the reagent combination comprises a) a T7 reverse transcription reaction reagent and b) a CRISPR-Cas13a reaction system; a) the T7 reverse transcription reaction reagent comprises a T7 reverse transcription primer and a T7 reverse transcriptase; and b) the CRISPR-Cas13a reaction system comprises specific crRNA, a fluorescence labeled ssRNA reporter, a reaction buffer solution, a Cas13a protein, RNase-Free H2O and a T7 reverse transcriptase. The invention also provides application of the reagent combination in detection of viable tubercle bacillus. The primer combination disclosed by the invention has the advantages of strong specificity and high sensitivity in detection application, can realize rapid detection and visual detection, and is low in detection cost, simple and convenient to operate and suitable for large-scale clinical application.

The invention discloses a biosensor based on an ultraviolet light triggered bio-barcode release technology (OBCA) and construction and application of the biosensor. The biosensor comprises nucleic acid functionalized silver nanoparticles, nucleic acid functionalized magnetic beads and a CRISPR (clustered regularly interspaced short palindromic repeats) / Cas12a detection system, the DNA bar code modified on the surface of the silver nanoparticle contains a light cleavable linker, a CRISPR / Cas12a activation sequence and a target capture sequence I, and a DNA capture probe containing a target capture sequence II is fixed on the surface of the magnetic bead through biotin-streptavidin action. During detection, target miRNA mediates two capture sequences to form a sandwich compound, after magnetic separation and thermal denaturation elution, 365nm ultraviolet radiation releases DNA bar code fragments, and the Cas12a trans-cleavage fluorescence quenching reporter probe is activated to generate a signal. According to the method, nucleic acid amplification and reverse transcription are not needed, the detection limits of miR-21, miR-155 and mi-210 respectively reach 158.94 aM, 763.56 aM and 197.82 aM, single-base mismatch and precursor miRNA can be distinguished, the serum sample detection result is highly consistent with that of RT-PCR, and the method is suitable for high-sensitivity quantitative detection of miRNA.

The application discloses a two-stage radiomics lesion identification and positioning method and device, adopts a multilayer perceptron network to analyze multi-modal image data, detects FCD by extracting features taking the gray matter as a region of interest by using a radiomics method, and the features combine shape, first-order statistics and texture features from multi-modal and wavelet images. In addition, the application also introduces asymmetric features of left and right hemispheres, avoids potential interference in the contralateral area of the unilateral FCD patient caused by the compensatory mechanism of the left and right hemispheres of epilepsy. According to the rich high-dimensional features and asymmetric features of radiomics, the sensitive features of FCD are fully explored, the two-stage detection method is combined to identify FCD abnormalities, the extracted features are more perfect, false positive results are avoided, and the accuracy and sensitivity of detecting FCD are improved from different scales from coarse to fine granularity.

The invention relates to the technical field of food safety detection, and discloses an immunochromatography kit for rapidly detecting rice yeast acid in food, which comprises a test strip and an extracting solution. The test strip is in lap joint with a sample pad, a combination pad, a nitrocellulose membrane and a water absorption pad in sequence; the nitrocellulose membrane is provided with a detection line coated with a rice yeast acid conjugate and a quality control line coated with an anti-mouse IgG antibody. The sample pad is pretreated by polyvinylpyrrolidone to intercept impurities; introducing a steric hindrance protective agent into the combination pad probe; the extracting solution contains methanol and a surfactant. Through a specific formula and process, the technical problems that in a lipid-containing and high-viscosity complex matrix, rice yeast acid is difficult to extract, chromatography is prone to blockage and false positive is caused by an organic solvent are solved, and the method has the advantages of being high in sensitivity, high in anti-interference capacity and rapid in detection and is particularly suitable for food poisoning site emergency disposal and daily rapid screening.

The invention discloses a preparation method and application of an electrochemical biosensor based on a self-protection palindromic DNA (deoxyribonucleic acid) nanosphere. The electrochemical biosensor comprises an HP-trigger, a target miRNA (micro ribonucleic acid) and a self-protection DNA palindromic nanosphere core structure. The DNA nanosphere is of a three-dimensional spherical structure formed by four single-stranded DNAs through complementary base pairing, the three single strands of SEP-Sa, SEP-Sb and SEP-Sc contain 12 nt palindromic cohesive ends and 15 nt single-stranded arms, the single strand of HP-Sc contains 35 nt prolonged hairpin structures, the structural stability is enhanced through a self-protection mechanism of a palindromic sequence, and structural dissociation triggered by target miRNA is achieved. The target miRNA is combined with an HP-Sc hairpin structure to trigger conformational change, release complementary chains and dissociate palindromic nanospheres, and exposed DNA sites are combined with MB to generate electrochemical signals, so that a novel tool is provided for early diagnosis of tumors.

The utility model provides a multi-channel medicine sampling device for sulfur tire compound metabolic kinetics research, which comprises a first section and a second section, the tail part of the first section is fixedly connected with the second section, the first section is made of glass, and the front end of the first section is detachably connected with a sampling head. The utility model has the advantages that the most part of the needle cylinder is made of inert materials such as glass, so that sample degradation or false positive results are prevented, the single sampling amount is small, the first section is designed to be made of enough glass materials, and the sampling head is made of stainless steel, so that sample residues and adsorption are reduced; the labels are large in area and capable of marking channel types, sampling time and animal numbers in an eye-catching mode, and manual recording errors are reduced. Meanwhile, in order to prevent the label from being mistakenly attached to the sampling device, an angle plate structure is designed for the first section, and the angle of the label is tilted, so that the label can be conveniently removed to replace a correct label.

This invention discloses a method and system for detecting pathogens in the conjunctival sac using fluorescence staining image analysis, belonging to the field of medical image processing technology. The method includes: acquiring multi-wavelength fluorescence images and performing inter-channel differential operations to construct a spectral response surface; identifying regions of abrupt curvature changes to determine candidate pathogen locations; extracting radial fluorescence intensity distribution curves; calculating attenuation gradients and transition band width matching rules to determine pathogen types; acquiring temporal fluorescence intensity; screening locations where the intensity change rate exceeds an activity threshold as active pathogen locations; identifying the diffusion axis based on spatial distribution; calculating the spatial density gradient based on statistical density changes; coupling the intensity change rate to calculate the diffusion rate and determine the warning region; identifying abnormal pixels within the warning region; verifying continuous growth characteristics through temporal tracking; confirming and marking early infection areas. This invention improves detection accuracy and timeliness, enabling early warning.

This invention discloses a TaqMan real-time fluorescent PCR detection primer and probe set, kit, and detection method for Cuscuta pentaphyllum. The primer and probe set includes: an upstream primer C. pan F, whose nucleotide sequence is shown in SEQ ID NO.1; a downstream primer C. pan R, whose nucleotide sequence is shown in SEQ ID NO.2; and a TaqMan probe C. pan P, whose nucleotide sequence is shown in SEQ ID NO.3. The primers and probe target specific fragments of the rbcL gene sequence of Cuscuta pentaphyllum, achieving specific recognition of Cuscuta pentaphyllum through sequence complementarity matching. This avoids false positive results caused by cross-reactions with closely related species and host plants at the molecular targeting level, effectively solving the problem of difficulty in distinguishing closely related species in traditional morphological identification. Compared with traditional morphological identification and conventional PCR, this invention also features high detection efficiency, short processing time, simple operation, and wide applicability. It is suitable for precise identification in professional laboratories and can also meet the practical applications in grassroots quarantine and field monitoring scenarios.

The present application relates to the field of antibodies, and in particular, the present application provides a high affinity PADI2 antibody and a preparation method thereof. Through antibody screening experiments, eight high affinity PADI2 antibodies are screened, the antibodies can specifically bind to PADI2 protein, and have high affinity. Experimental results show that the antibodies of the present application exhibit excellent binding capacity in ELISA, Western blot and cell experiments, and can be used for detection, diagnosis and treatment of PADI2 related diseases.

The invention relates to the technical field of biological detection, and discloses a primer, a probe and a kit for detecting aeromonas hydrophila based on fluorescent PCR (Polymerase Chain Reaction) and application of the primer, the probe and the kit. A primer and fluorescent probe combination is obtained by designing and screening a specific gene conserved region of aeromonas hydrophila. The specific amplification of the aeromonas hydrophila gene based on the fluorescent PCR technology can be successfully realized. According to the method, the detection accuracy and sensitivity are improved, the aeromonas hydrophila can be detected in the early stage of bacterial septicemia of silver carps and bighead carps, prevention and control of bacterial septicemia of silver carps and bighead carps are facilitated, and the basic requirements of field detection of farms can be met.

The present application relates to the technical field of molecular detection and diagnosis, and particularly relates to a tetrahedral probe, a preparation method thereof and application of the tetrahedral probe in detection of apurinic / apyrimidinic endonuclease 1 (APE1). The DNA tetrahedral probe is formed by self-assembly of a frame DNA chain, a triple helix complex and a hairpin H chain. The frame DNA chains interact to form a stable tetrahedral skeleton; when APE1 exists in a sample, it can specifically recognize and cut apurinic / apyrimidinic sites on the triple helix complex and the hairpin H chain, trigger a cascade reaction and realize signal amplification; nucleic acid drugs in the probe are released with the cutting, and thus the synergy of detection and treatment is realized. The technical solution can solve the technical problem of unsatisfactory sensitivity and accuracy of in vitro detection of APE1 enzyme in the prior art, has low detection limit and wide linear range. The technical solution has important clinical application value and scientific research significance, and is expected to promote the development of non-small cell lung cancer diagnosis and treatment technology.

The invention discloses a rabbit-derived single B cell antibody of porcine reproductive and respiratory syndrome virus (PRRSV) nucleocapsid protein, a fusion protein, a detection kit and a detection method. The invention provides two rabbit-derived single B cell antibodies T-11 and T-12, wherein amino acid sequences of variable regions of a heavy chain and a light chain of the rabbit-derived single B cell antibodies T-11 and T-12 are respectively shown as SEQ ID No.1-4; also provided are PRRSV-1 type and type 2 nucleocapsid protein fusion proteins BiN-2 (SEQ ID No.5) and antibody compositions comprising T-11 and T-12. Based on the antibody and the fusion protein, a competitive ELISA detection method and a kit are established, T-11 is used for capturing BiN-2 to construct an indirect coating antigen, biotin-labeled T-12 is used as a competitive antibody, and a judgment result is detected through an enzymatic reaction and a light absorption value. The method can be used for simultaneously detecting the PRRSV-1 type and the PRRSV-2 type antibodies, the sensitivity and the specificity both reach 97% or above, the method has no cross reaction with other porcine virus antibodies, the operation is simple and convenient, the stability is good, and a reliable tool is provided for accurate prevention and control of PRRS and epidemiological monitoring.

The invention discloses an NFE2L3-multi-tag fusion stable cell line, a special tool and a construction method and application of the NFE2L3-multi-tag fusion stable cell line, and belongs to the technical field of crossing of molecular biology and cell biology. According to the invention, a CRISPR-Cas9 gene editing technology is adopted, multiple types of tags such as GFP, Flag and the like are inserted in the same frame in front of a termination codon of an NFE2L3 gene, and specific sgRNA targeting NFE2L3, a universal HDR donor vector and a construction composition are provided in a matched manner. The construction method comprises the steps of sgRNA design, donor vector construction, adaptability delivery and positive screening, and overcomes the defects of unstable expression, gene function interference and the like in the prior art. The obtained cell line can avoid the problem of insufficient NFE2L3 special antibodies, is suitable for ChIP-seq, living cell imaging and other experiments, assists downstream target gene analysis, upstream regulatory factor screening and stress condition response identification, and provides an efficient tool for NFE2L3 functional mechanism and tumor related research.

The invention relates to a drainage biotoxicity monitoring device and method based on a camera tracing technology, and the device comprises a monitoring box body, the box body comprises a box wall, the interior of the box body comprises an upper continuous toxicity test area and a lower mixed control area, the continuous toxicity test area is internally provided with a monitoring auxiliary device, and the continuous toxicity test area comprises a breeding container. The monitoring auxiliary device comprises a camera, a sliding rail and a lamp box, the sliding rail and the lamp box are arranged on the box wall, the camera is installed on the sliding rail, the mixing control area comprises a wet area, a mixing area and a dry area, a temperature control structure, an aeration structure and a sewage premixing structure are arranged in the wet area, and the mixing area is provided with a water pump and a water pipeline box. The dry area is provided with a power supply controller for controlling the continuous toxicity test area, the mixed control area and the monitoring auxiliary device. The device is high in anti-interference capability and can be arranged on site in an industrial device area with a complex environment, parallel experimental groups are arranged, and false positive results caused by individual differences of experimental fishes are effectively avoided.

The invention relates to the technical field of PCR (polymerase chain reaction) detection, in particular to a specific primer pair, a primer probe combination and a kit for detecting white spot syndrome virus, the primer probe combination comprises a specific primer and a probe aiming at the white spot syndrome virus, and the primer and the probe have good specificity, sensitivity and repeatability. And in combination with an optimized real-time fluorescent PCR detection method, rapid and accurate identification of the white spot syndrome virus can be realized. The kit can realize high-sensitivity detection of the white spot syndrome virus, is suitable for early diagnosis of low-load viruses, is stable and reliable in detection result, and can meet standard detection requirements of laboratories; the kit is simple and convenient to operate, short in detection period and suitable for rapid screening application in primary laboratories. The invention provides efficient and practical detection technical support for early warning of white spot syndrome virus, prevention and control of epidemic situation and healthy development of shrimp and crab breeding industry, and has good popularization and application prospects.

This invention discloses a primer set, probe set, and kit for genetic risk detection of venous thromboembolism (VTE) in the Han Chinese population, belonging to the field of gene detection technology. The primer set is designed for seven key SNP sites associated with VTE in the Han Chinese population, covering anticoagulation, fibrinolysis, and metabolic systems. The probe set is paired with the primer set and uses multicolor fluorescent labeling. The kit contains the aforementioned primer set, probe set, and PCR buffer, and other core reagents, employing fluorescent multiplex PCR technology to accurately distinguish genotypes based on differences in melting curves. This invention closely matches the genetic characteristics of the Han Chinese population, offering excellent detection accuracy and specificity. It is simple and quick to operate, requires no complex equipment, and is cost-effective. It can rapidly assess genetic risk, facilitating early screening and prevention of VTE, and is suitable for large-scale application in medical institutions at all levels.

This invention discloses a method for fine mapping of QTLs for important traits in mulberry trees based on chromosome segment substitution lines, belonging to the field of molecular breeding technology. It includes: S1: Constructing a genotype-phenotype association matrix: The backcross population is screened through high-heterozygous parental hybridization and multiple generations of backcrossing, and the genomes of the screened backcross population are marked using targeted sequencing and recombination hotspots; S2: Phenotypic modeling: Samples are collected from the experimental plants, and a hybrid model is obtained based on the environmental effects of the experimental plants and the covered CSSL lines; S3: Gene screening: Hub genes are screened using the constructed co-expression network model and hybrid model. This invention dynamically marks the genome through multiple generations of backcrossing, targeted sequencing, and recombination hotspot analysis, and constructs a tiered covered CSSL library, thereby effectively compressing QTL intervals and overcoming the mapping ambiguity problem caused by limited recombination events in traditional F2 or RIL populations.