Abstract: The present invention provides a polysaccharide-magnetic metal oxide complex consisting of a polysaccharide derivative obtained by carboxyalkyl-etherifying and unsubstituted or substituted aminoalkyl-etherifying a polysaccharide (the above carboxy group and/or amino group may be of a salt form) and a magnetic metal oxide. The above complex has a slow blood clearance and a low toxicity and is useful as a nuclear magnetic resonance imaging contrast medium.

Abstract: A water-soluble carboxypolysaccharide-magnetic iron oxide complex of small particle diameter composed of a water-soluble carboxypolysaccharide and a magnetic iron oxide having a core diameter ranging from about 2 to about 7 nm, wherein the total diameter ranges from about 10 to about 50 nm, the ratio of the total diameter to the core diameter is about 15 or less, and the T.sub.2 -relaxivity ranges from about 10 to about 150 (mM.sec).sup.-1. Said complex has low toxicity and small side effects and is useful in the fields of medical treatment, biology and engineering as an iron-supplementing agent, an X-ray contrast medium, an MRI contrast medium, a reagent for blood flow rate measurement, a carrier for drug administration, etc.

Abstract: An oxidized complex comprising a water-soluble carboxypolysaccharide and magnetic iron oxide, which is characterized by being obtained by oxidizing a complex comprising a water-soluble carboxypolysaccharide and magnetic iron oxide. Said oxidized complex has very low toxicity, is very stable, exhibits little or no blood pressure-reducing action and has low platelets-aggregating action when administered directly into the blood vessels of animals, and is useful in medical fields such as contrast medium for magnetic resonance imaging, exothermic medium for hyperthermia and the like.

Abstract: A composition containing magnetic metal oxide ultrafine particles, which comprises an aqueous sol of a complex of the magnetic metal oxide ultrafine particles with a polysaccharide, a polysaccharide derivative and/or a protein; and an organic monocarboxylic acid. The composition is free of side effects such as platelet aggregation, is safe for use with living bodies, and, in the case of intravascular administration, has no harmful effects on living bodies, and is useful in fields such as medicine and diagnostic drugs.

Abstract: .beta.-1,3-glucanpolyol derived from .beta.-1,3-glucan produced by a .beta.-1,3-glucan-producing strain of the genus Pestalotia, said glucanpolyol having an intrinsic viscosity [.eta.] of about 1 to about 10 and comprising a main chain having as repeating units .beta.-1,3-glucopyranose units of the following formula.fwdarw.3) .beta.-D-Glc (1.fwdarw.wherein Glc represents a glucopyranose residual moiety, and bonded thereto, either side chains of formula (B), or both side chains of formulas (A) and (B) below ##STR1## wherein n represents a number of from 0 to 1, and .fwdarw.3) .beta.-D-Glc (1.fwdarw. represents the above main chain, and R represents a group derived from .beta.-D-glucopyranose of the formula ##STR2## a process for production thereof, and its pharmaceutical use.

Abstract: A pharmaceutical composition containing as its active ingredient a disaccharide derivative having a derivative group of the following formula (1) bonded to a carbon atom of a disaccharide: ##STR1## wherein Y is a member of the group consisting of NH and O; and when Y is NH, Z is a member of the class consisting of --O-- (disaccharide residue) and --O--, with the proviso that one of the two bonds is attached to the other carbon atom of the same disaccharide to which the formula (1) group is bonded, and when Y is O, Z is a member of the class consisting of --NH.sub.2 and --O--, with the proviso that one of the two bonds is attached to a carbon atom of a disaccharide different from that to which the formula (1) group is bonded. The disaccharide derivative can be prepared by reacting a disaccharide with an activating agent selected from the group consisting of the cyanogen halides, organic cyanic acid esters and halogenocarbonic acid alkyl esters.