Abstract: Disclosed is a filter material for selectively removing leukocytes from a leukocyte-containing suspension, which comprises a porous element having an average pore diameter of 1 to 25 .mu.m and a total pore volume of 0.40 to 0.95 ml/ml of the porous element, and wherein the sum of respective pore volumes of pores of the porous element which have a pore diameter of 1 to 30 .mu.m is 90% or more, based on said total pore volume. Also disclosed is a filter apparatus for selectively removing leukocyte from a leukocyte-containing suspension which is packed with the above-mentioned filter material. By virtue of the filter material, the filter apparatus not only can remove leukocytes from a leukocyte-containing suspension at a leukocyte removal efficiency as excellent as 10.sup.-4 or less in terms of a leukocyte residual ratio without suffering from a pressure loss increase, but also can be rendered compact.

Abstract: Disclosed is a filter material for selectively removing leukocytes from a leukocyte-containing suspension, which comprises a porous element having an average pore diameter of 1 to 25 .mu.m and a total pore volume of 0.40 to 0.95 ml/ml of the porous element, and wherein the sum of respective pore volumes of pores of the porous element which have a pore diameter of 1 to 30 .mu.m is 90% or more, based on said total pore volume. Also disclosed is a filter apparatus for selectively removing leukocyte from a leukocyte-containing suspension which is packed with the above-mentioned filter material. By virtue of the filter material, the filter apparatus not only can remove leukocytes from a leukocyte-containing suspension at a leukocyte removal efficiency as excellent as 10.sup.-4 or less in terms of a leukocyte residual ratio without suffering from a pressure loss increase, but also can be rendered compact.

Abstract: An adsorbent for .beta..sub.2 -microglobulin is disclosed, which comprises a water-insoluble carrier having supported thereon, as a ligand, at least one electrolyte selected from the group consisting of a polyamino acid, a polysaccharide, a synthetic high polymer, collagen having an isoelectric point of 9.5 or more, and gelatin having an isoelectric point of 6.5 or more, wherein said electrolyte has a molecular weight not less than 1,000 and an X value of more than 2.0, wherein X is a relationship regarding the skeleton structure of said electrolyte and is the sum of A and B, wherein A represents (the number of carbon atoms of the skeleton structure)-(the number of hydrophilic groups)/(the number of hydrophilic groups); and B represents .vertline.(the number of cationic groups)-(the number of anionic groups).vertline./(the number of hydrophilic groups). The adsorbent exhibits adsorptivity for .beta..sub.2 -microglobulin at high efficiency and high selectivity.

Abstract: A method of inducing antitumor immunocytes which is simple in operation and suitable for inducing antitumor immunocytes having not only excellent cytotoxic activity against tumor cells but also high safety, which method comprises contacting leucocytes with an insoluble, antitumor immunocyte-inducing material capable of linking with T cells, said antitumor immunocyte-inducing material comprising an insoluble carrier and a ligand linked therewith. The induced antitumor immunocytes can be simply separated in substantially ligand-free form from the insoluble, antitumor immunocyte-inducing material. The obtained antitumor immunocytes have not only excellent cytotoxic activity against tumor cells but also high safety.

Abstract: An adsorbent for adsorbing thereonto an autoantibody and/or immune complexes from a body fluid. The adsorbent comprises a surface, a hydrophobic member and a negative charge-producing member. The negative charge-producing member is adapted to produce such an effective number of negative charges in a body fluid that the ratio of: ##EQU1## is greater than 1. The adsorbent is excellent in selectively and efficiently adsorbing an autoantibody and/or immune complexes while little adsorbing useful substances from the body fluid. The adsorbent may be used in an adsorbing device comprising a vessel having a fluid inlet and a fluid outlet with the adsorbent contained in the vessel.

Abstract: An adsorbent for adsorbing low density lipoproteins, which comprises a surface and, linked with the surface, at least one member selected from a silanol group and a synthetic polyanion member having a molecular weight of 600 or more, and has pores of diameters widely distributed in a specific range. The adsorbent has a high adsorbing capacity for low density lipoproteins and is useful for purifying and regenerating a body fluid with high selectivity for low density lipoproteins.

Abstract: An immune adsorbent for autoantibodies and/or immune complexes is provided which is comprised of a water-insoluble carrier and at least one low-molecular-weight substance containing a purine base or pyrimidine base as a constituent element, which is fixed to said carrier. The immune adsorbent is usually used in an adsorption apparatus comprising a vessel having fluid inlet and outlet openings and having packed therein said immune adsorbent.

Abstract: Aquatic animals can be kept in a living condition over a long period of time, without feeding them, by placing the aquatic animals, at a large density of more than 200 kg/m.sup.3 in environmental water; maintaining the temperature of the environmental water in a lowest possible range in which it is possible for the aquatic animals to exist; controlling the concentrations of ammonia compounds, water-soluble organic compounds and carbonic acid radical in the environmental water so that their levels do not exceed 20 ppm, 150 ppm and 1,000 ppm, respectively; and regulating the concentration of molecular oxygen dissolved in the environmental water so that it is 3 ppm or more.

Abstract: Aquatic animals can be kept in living condition over a long period of time by placing the aquatic animals in environmental water in a large density of more than 200 kg/m.sup.3 ; maintaining the temperature of the environmental water at a lowest possible level in which it is possible for the aquatic animals to exist; controlling the concentrations of ammonia compounds, water-soluble organic compounds and carbonic acid radical in the environmental water so that their levels do not exceed 20 ppm, 150 ppm and 1,000 ppm, respectively; and regulating the concentration of molecular oxygen dissolved in the environmental water so that it is 3 ppm or more.

Abstract: Aquatic animals can be kept alive over a long period of time by utilizing the apparatus of the present invention comprising:a water tank for containing aquatic animals and environmental water, which tank has an inside volume large enough to contain the aquatic animals in an amount greater than 200 kg per m.sup.