Abstract: The present invention provides an absorbable barrier membrane for guided tissue regeneration which is useful for regeneration of animal tissues, including those of humans, the absorbable barrier membrane being superior in heat stability, processability, reproducibility, storage stability, bioabsorbablity, and tissue regeneration effects, and further provides a method for regeneration, using the absorbable barrier membrane, of a mandible, periodontal tissue, or defective tubulous bone, and particularly a defective tubulous bone which possesses a segmental bone defect in which both ends of the bone are in separate segments. The above objects are attained by an absorbable barrier membrane for use in guided tissue generation, comprising a lactic copolyester in which a polymerization catalyst is deactivated, as an essential component.

Abstract: The present invention relates to chromogenic compounds which are represented by the general Formula (I): ##STR1## wherein R.sub.1 is a sugar group, ester group, hydrocarbyl group, phosphate group, sulfate group or a salt thereof, with the proviso that R.sub.1 is other than .beta.-D-glucuronic acid or .beta.-D-galactopyranoside, R.sub.2 is H or hydrocarbyl group containing 1 to about 5 carbon atoms, X is Cl or H, and Y is Cl or H. The present invention further relates to a method for quantitatively identifying and differentiating a first biological material having enzyme specificity for a first chromogenic compound as represented by Formula (I) above, and a second biological material having enzyme specificity for a second chromogenic compound.

Abstract: A chromogenic .beta.-galactosidase substrate producing an insoluble precipitate of a first color when reacted upon by .beta.-galactosidase and a chromogenic .beta.-glucuronidase substrate producing an insoluble precipitate of a second, contrasting color when reacted upon by .beta.-glucuronidase are combined in test medium for quantitatively identifying and differentiating general coliforms and E. coli. The .beta.-galactosidase substrate 5-bromo-4-chloro-3-indolyl-.beta.-D-galactopyranoside which produces an indigo blue precipitate when reacted upon by .beta.-galactosidase may be used with one of the novel compounds 6-chloroindolyl-.beta.-D-glucuronide, 4,6-dichloroindolyl-.beta.-D-glucuronide, 6,7-dichloroindolyl-.beta.-D-glucuronide, and 4,6,7-trichloroindolyl-.beta.-D-glucuronide, which produce mauve or magenta precipitates when reacted upon by .beta.-glucuronidase. The .beta.-glucuronidase substrate 5-bromo-4-chloro-3-indolyl-.beta.

Abstract: A method for growing a single crystal of a cubic boron nitride semiconductor in a growing container sealed under high pressure and high temperature conditions, which comprises dissolving in a dopant-containing boron nitride solvent a boron nitride starting material placed at a high temperature zone in the growing container, and providing a temperature gradient to the solvent so that the temperature dependence of the solubility is utilized to let the single crystal form and grow at a low temperature zone in the growing container.

Abstract: Novel amino-hydroxy-alkylene sulfonic acid zwitterions are described which have the general formulas ##STR1## wherein A and B are each independently a hydrogen atom, an aliphatic, cycloaliphatic or hydroxyaliphatic group,n is one or two, andR.dbd.N is a cyclic radical comprising one or two ring nitrogen atoms, zero or one ring oxygen atoms and the remainder of the ring being carbon atoms, and water soluble salts of said acids. These organo-sulfonic acid compounds are useful as hydrogen ion buffers in biological research and particularly for tissue culture.

Abstract: Novel amino-hydroxy-alkylene sulfonic acid zwitterions are described which have the general formulas ##STR1## wherein A and B are each independently a hydrogen atom, an aliphatic, cycloaliphatic or hydroxyaliphatic group,N is one or two, andR.dbd.n is a cyclic radical comprising one or two ring nitrogen atoms, zero or one ring oxygen atoms and the remainder of the ring being carbon atoms, and water soluble salts of said acids. These organo-sulfonic acid compounds are useful as hydrogen ion buffers in biological research and particularly for tissue culture.