摘要:
Polyacrylamide gels that offer high resolution as electrophoretic media for protein separations and an improved resistance to hydrolysis upon storage are made by including either taurine, asparagine, or both as an ampholyte, in combination with either tris(hydroxymethyl)-aminomethane or bis(2-hydroxyethyl)amino-tris(hydroxymethyl)methane as a buffer, plus other conventional components.
摘要:
A reagent for use in immunoassays reduces interference in particle agglutination assays. The reagent contains particles having covalently bound antibodies and a tertiary amine compound of formula (I): N(R1—X)(R2—Y)(R3—Z) (I). The moieties R1, R2, and R3 are independently alkyl or alkyl ether. The moieties X, Y, and Z are independently —OH, —O—R4, —S—R4, —C(═O)—OH, —C(═O)—OR4, or —C(═O)—NHR4 (R4 is alkyl).
摘要:
Cyanide-free reagents for the determination of hemoglobin and leukocytes present in a blood sample comprise an aqueous solutions of at least one quaternary ammonium salt, preferably selected from the group of alkyltrimethylammonium salts, alkyldimethylbenzylammonium salts or alkylpyridium salts consisting of tetradecyltrimethyl ammonium bromide (TTAB), dodecyltrimethyl ammonium chloride, cetyltrimethyl ammonium bromide, hexadecyltrimethyl ammonium bromide and benzalkonium chlorides, and hydroxylamine salts, especially hydrochloride, sulfate and phosphates and other acid salts. The method involves mixing the reagent with a diluent-diluted blood sample, presenting it to an absorbance spectrophotometer and measuring the resulting optical density as an indicator of hemoglobin concentration. This cyanide-free reagent could be used solely for hemoglobin determinations, or, it can also be used in leukocyte counting and sizing using hematology instrumentation.
摘要:
The present invention relates to a method for measuring the amount of vitamin D metabolite in a sample of plasma or serum, comprising the step of (a) adding to a serum or plasma sample a non-competitive displacement agent to effect separation of any vitamin D metabolite in the sample form protein to which it is bound, such that any vitamin D metabolite may be detected and/or measured; and (b) detecting or measuring the amount of vitamin D metabolite in the sample of (a). Such methods are useful in determining the vitamin D status of the subject, for example in the diagnosis of disease. Also provide are agents and kits for use in performing the methods of the invention.
摘要:
This invention relates to preservative solutions for peptides, for example, parathyroid hormone, insulin-like growth factor binding protein 3 (IGFBP3), adrenocorticotropic hormone (ACTH) and mixtures thereof. Preferably, the peptides preserved by the solutions are non-reconstituted. In one embodiment, the preservative solutions comprise a polyvinyl alcohol, EDTA component and molybdic component.
摘要:
Improved methods, reagents, and kits for quantitation of HLA-DR and/or CD11b expression on peripheral blood cells are presented. Inclusion of a lysosomotropic amine, such as chloroquine, during staining stabilizes HLA-DR and CD11b expression. Use of a novel anti-CD14 conjugate, anti-CD14-PerCP/CY5.5, permits the ready discrimination of monocytes. The improved methods, reagents, and kits may be used to assess immune competence, and to direct and monitor immunostimulatory therapies in septic patients exhibiting monocyte deactivation.
摘要:
Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel. Finally, an electric response of the oocyte caused by the contact with the solution is detected and the concentration of the histamine released in the histamine releasing reaction in the fine reacting tube is determined. The entire blood or mast cell suspension may be used as a sample without pretreatment.
摘要:
Recombinant DNA expression vectors or cloning vehicles capable of expressing a polypeptide displaying the antigenicity of an allergen of house dust mites of the genus Dermatophagoides. A synthetic protein or polypeptide displaying antigenicity of all or a portion of an allergen of house dust mites of the genus Dermatophagoides. Methods of diagnosing and treating such allergies.
摘要:
This invention provides a method for preserving cells which comprises the steps of (a) suspending cells in a physiologically-acceptable, isotonic medium; and (b) fixing the cells so suspended at a temperature of less than about 10.degree. C. under sufficiently hypertonic conditions so as to disperse the cells in a single, unagglutinated state, thereby preserving cells. This invention also provides a method for detecting cells separated from a sample which have been preserved according to the aforementioned method. This invention also provides a method for visualizing cells. Also provided is a method for detecting a metabolic process in cells present in a sample. This invention also provides a method for detecting the presence of rare cells in a sample which specifically possess on their surfaces a moiety recognized by a known ligand comprising preserving cells separated from the sample according to the aforementioned method for preserving cells. The subject invention also provides for quantitatively determining and isolating rare cells detected according to the aformentioned method. Further provided are methods for determining whether a fetus is afflicted with a genetic abnormality, determining the gender of a fetus, determining whether a subject is afflicted with a tumor, and detecting in a subject the presence of cells expressing a malignant phenotype, each method comprising preserving cells according to the aforementioned method for preserving cells.
摘要:
An aqueous composition suitable for use when performing immunological procedures. The composition includes at least one biological buffer, dithiothreitol (alternatively referred to herein as "DTT"), and ethylene glycol. The composition can also include at least one biological detergent, at least one source of positive and negative counterions, e.g., salt, and at least one viscosity modifier, e.g., sugar. The buffer also can include at least one preservative, such as sodium azide. The pH of the composition preferably ranges from about 6.4 to 7.2. A kit containing the composition is also disclosed.