32results about How to "Avoid cancer risk" patented technology

The invention provides an amplification method of pancreatic cells. The amplification method comprises the following steps: sequentially carrying out digestion treatment, resuspension treatment, discontinuous density gradient centrifugation treatment and amplification treatment on pancreatic tissues. According to the amplification method disclosed by the invention, pancreatic ducts of mammals are used as sources of pancreatic precursor-like cells, and islet cells and acinar cells in obtained cell clusters are removed after the discontinuous density gradient centrifugal treatment, thus being good for improving the yield of pancreatic precursor-like cells, and avoiding ethical limitations and possible carcinogenic risk caused by the use of embryonic stem cells; and an amplification culture medium used in the invention comprises a reprogramming substance consisting of a plurality of small molecule compounds, so as to avoid the risks of nonspecificity, off-target deletion, etc., which are easily caused by changing gene sequences by using a gene editing method. The invention also provides a differentiation method and application of the pancreatic precursor-like cells obtained by the amplification method.

The invention discloses a chitosan quaternary ammonium salt couplant and a preparation method thereof. The chitosan quaternary ammonium salt couplant is prepared from 0.1-0.9wt% of Carbomer 941, 0.5-6wt% of phenoxyethanol, 0.01-1.0wt% of hydrochloric acid, 0.1-0.8wt% of chitosan quaternary ammonium salt, 1.2-10wt% of triethanolamine, 2-20wt% of a humectant and the balance distilled water. The chitosan quaternary ammonium salt couplant has the advantages of good bactericidal effects, good environmental performances, no carcinogenesis on the human body, clarification, transparency, alcohol fragrance, good homogeneity and good fineness.

The invention belongs to the field of metal machining fluids, and discloses a heavy-load metal machining total synthesis cutting fluid as well as a preparation method and an application thereof. The total synthesis cutting fluid comprises the following components in percentage by weight: 20%-30% of mixed alcohol amine, 6%-9% of anti-rust agents, 4%-6% of special amine, 6%-10% of lubricating agents, 15%-25% of extreme pressure agents, 6%-10% of cosolvents, 1%-2% of water-softening agents, 1%-3% of corrosion inhibitors and the balance of water. The total synthesis cutting fluid disclosed by the invention has excellent lubricating extreme pressure property, can meet the requirement for heavy-load machining, namely reaming, drilling, tapping, threading, broaching, thread machining and the like, of difficult-to-machine materials, namely high-temperature alloy steel, a titanium alloy and the like; a product is green and environment-friendly without containing boron, sodium nitrite, secondary amine, chlorine, phenol, formaldehyde, heavy metals and the like; in addition, the total synthesis cutting fluid disclosed by the invention has excellent anti-rust property, biological stability and machining property, and can enhance the surface quality of a machined part, prolong the service life of a cutter and reduce the rejection rate, thus improving the production efficiency.

The invention relates to the technical field of room temperature curing silicone rubber, in particular to a non-corrosive ketoxime type room temperature curing silicone rubber and a preparation method. The formula of ketoxime type room temperature curing silicone rubber consists of 40-60 parts by weight of hydroxyl-terminated polysiloxane, 3-6 parts of methyl isobutyl ketoximosilane, 1-5 parts of silane coupling agent, plasticizer 5 to 15 parts, 0.1 to 1 part of catalyst, 10 to 30 parts of filler, and 1 to 10 parts of pigment are obtained by mixing hydroxyl-terminated polysiloxane, plasticizer, filler and pigment, and then adding methyliso butanone oximino silane, a silane coupling agent, a catalyst, and vacuum stirring to obtain a room-temperature-cured silicone rubber compound. The methyl isobutyl ketone oxime produced during the vulcanization process of the ketoxime type room temperature curing silicone rubber is non-corrosive to polyurethane materials, and meets the needs of the automobile and electronics industries for ketoxime type room temperature curing silicone rubber. The colloid has high tensile strength, In addition, the bonding performance of the rubber material is strong, and the preparation method is simple.

The invention belongs to a medical biological material technology field, concretes a chitosan fiber film, wherein the fiber film is prepared from a chitosan spinning solution, which is a mixed solution containing chitosan, hexafluroisopropyl alcohol and acetate. The invention further provides a method for preparing the chitosan fiber film, and applications of the fiber film for preparing endocranium or endorhachis defect repairing material, cerebrospinal fluid leakage plugging material or a tissue adhesion prevention medicament.

The invention belongs to the field of regenerative medicine materials, and in particular relates to an antibacterial cation-modified absorbable pachymeninx repair material and a preparation method and application thereof. The antibacterial cation-modified absorbable pachymeninx repair material is of a double-layer structure consisting of a degradable polyester nanofiber membrane modified by epsilon-polylysine and a three-dimensional porous high-molecular material. The absorbable pachymeninx repair material provided by the invention has excellent antibacterial characteristic, can effectively prevent postoperative intracranial infection, and can be directly attached and sewed for use; product compositions and a preparation process are simple, and industrial production are easily realized. The antibacterial cation-modified absorbable pachymeninx repair material of the invention is a novel medical biological material which is novel in structure and excellent in performance, and presents a good application prospect in the field of pachymeninx defect repair.

The invention belongs to the field of hepatitis B virus-infected cell models in life sciences and medicine, and provides a liver precursor-like cell model derived from primary liver cells for hepatitis B virus infection, a preparation method and an application thereof. The cell model is composed of three-dimensionally differentiated functional liver cells. The three-dimensionally differentiated functional liver cells are obtained from the liver precursor-like cells obtained after transformation and culture of human primary liver cells in vitro, and then undergo three-dimensional culture and liver maturation culture. It has been verified by experiments that the liver precursor-like cell model in the present invention can highly express HBV infection-related genes such as RXRA, HNF4A, and NTCP after being infected with HBV, and can be used for research on hepatitis B virus infection or co-cultured with HBV for preparation of hepatitis B virus-infected cells Model.