Abstract: A needle guiding bracket with adjustable angles is provided, comprising a bracket body, a mounting base, and an angle block; the angle block and the mounting base are rotationally connected at corresponding first ends, and a cooperating limiting structure is provided between the angle block and the mounting base to enable the angle block and the mounting base to only relatively rotate; a second end of the angle block is provided with at least one elastic arm having raised positioning platforms; a second end of the mounting base is provided with at least one group of angle gear grooves for the raised positioning platforms to be embedded therein; and the angle block is further provided with an elastic element which applies elastic force to the elastic arms so as to enable the raised positioning platforms to be embedded within the angle gear grooves.

Abstract: The present application relates to a biopsy needle having three usage modes, comprising an upper cover, a base, an inner needle assembly, an outer needle assembly, a loading assembly, a first rear emission assembly, a second rear emission assembly, a first side emission assembly and a second side emission assembly. The outer needle assembly and the inner needle assembly are loaded in sequence by the loading assembly, the inner needle assembly is emitted by the first rear emission assembly or the first side emission assembly, the outer needle assembly is emitted by the second rear emission assembly or the second side emission assembly, and the inner needle assembly can also be emitted by the second rear emission assembly or the second side emission assembly when it is not emitted, so that three usage modes are provided for users, and the users can select a rear emission or side emission operation.

Abstract: The present disclosure provides methods and systems for systematic elimination of background DNA in a DNA mixture sample. Often, the DNA of interest is in a heavy background of DNAs from other tissues. For example, a majority of DNA in plasma cell-free DNA originates from white blood cells. The present disclosure exploits genome-wide background DNA methylation to systematically eliminate DNA from white blood cells and normal tissue(s), therefore enriching non-background DNA for diagnostics, for example, the diagnostics of cancer and infectious diseases. The methods and systems may comprise the selection of targeted regions to generate one or more hybrid capture panels, digest nucleic acid molecules of specific methylation status with one or more restriction enzymes, retrieve the remaining DNA using the hybrid capture panel, sequence the captured DNA, analyze the sequencing data of the captured DNA, and diagnose diseases.

Abstract: A device for adjusting biopsy angles and a biopsy needle guide are provided. The device for adjusting biopsy angles comprises an angle fixing base and a needle guiding base, the needle guiding base being rotatably connected with the angle fixing base at their first ends, the needle guiding base having a needle tract for guiding a biopsy needle, wherein an U-shaped limiting assembly formed on one side of the needle guiding base surrounds a angle fixing sheet extending from the angle fixing base at their second ends, and a positioning adjuster mounted on the U-shaped limiting assembly is movably engaged with positioning holes on the angle fixing sheet so as to be inserted into the positioning holes or be released out of the positioning holes. The needle guiding base can be rotated at a large angle to disengage from the angle fixing sheet, and is convenient for cleaning.

Abstract: A device for adjusting biopsy angles and a biopsy needle guide are provided. The device for adjusting biopsy angles comprises an angle fixing base and a needle guiding base, the needle guiding base being rotatably connected with the angle fixing base at their first ends, the needle guiding base having a needle tract for guiding a biopsy needle, wherein an U-shaped limiting assembly formed on one side of the needle guiding base surrounds a angle fixing sheet extending from the angle fixing base at their second ends, and a positioning adjuster mounted on the U-shaped limiting assembly is movably engaged with positioning holes on the angle fixing sheet so as to be inserted into the positioning holes or be released out of the positioning holes. The needle guiding base can be rotated at a large angle to disengage from the angle fixing sheet, and is convenient for cleaning.

Abstract: A needle guiding bracket with adjustable angles is provided, comprising a bracket body, a mounting base, and an angle block; the angle block and the mounting base are rotationally connected at corresponding first ends, and a cooperating limiting structure is provided between the angle block and the mounting base to enable the angle block and the mounting base to only relatively rotate; a second end of the angle block is provided with at least one elastic arm having raised positioning platforms; a second end of the mounting base is provided with at least one group of angle gear grooves for the raised positioning platforms to be embedded therein; and the angle block is further provided with an elastic element which applies elastic force to the elastic arms so as to enable the raised positioning platforms to be embedded within the angle gear grooves.

Abstract: The present disclosure provides methods and compositions for preparation of a nucleic acid library. In some embodiments, the nucleic acids comprise cell-free DNA, including cfDNA that is in need of analysis, such as by sequencing. The methods may comprise restriction enzyme digestion, adapter ligation, and subsequent amplification, and may provide improved approaches for reducing the number adapter dimers produced during the process. In an aspect, a method for preparing a library of nucleic acids may comprise: digesting DNA molecules with restriction enzymes to produce DNA fragments; ligating adapters to the DNA fragments by incubating with ligase to produce a mixture of adapter-ligated DNA fragments and adapter dimers; amplifying the adapter-ligated DNA fragments to produce amplified adapter-ligated DNA fragments; and reducing the quantity of the adapter dimers by differentiating between the junction between an adapter and a DNA fragment, and the junction between an adapter and another adapter.

Abstract: The present disclosure concerns embodiments related to methods of enriching particular DNA for analysis of methylation status and/or profiles, for example in the process of diagnosis of cancer. In particular embodiments, the methods utilize cell-free DNA as a source of DNA instead of genomic DNA and allow for focused enrichment of fragments having two or more enzyme digestion sites and containing at least one CpG site.