Abstract: A polypeptide represented by the following general formula (I): ##STR1## wherein X.sub.1 means a hydrogen atom, acetyl group of amino acid residue, X.sub.2 and X.sub.3 are either the same or different and mean individually an amino acid residue, and when X.sub.2 stands for Cys, X.sub.3 denotes an amino acid residue other than Cys.

Abstract: A preparation containing an absorption promoter selected from N-acyl amino acid derivatives or N-acyl peptide derivatives represented by the formula: R-CO-A (R is an aliphatic hydrocarbon group, an aromatic hydrocarbon group or an aryl-substituted lower hydrocarbon group which may optionally be substituted, and A is an amino acid residue or a peptide residue), preferably in the presence of a salt at a concentation exhibiting higher osmotic pressure than isotonic sodium chloride solution, and a medicine is found to promote absorption of the medicine through a gastrointestinal organ such as the colon and rectum, and through the vagina.

Abstract: A polypeptide represented by the following general formula (I):X.sub.1 Ala Thr Lys Ala Val X.sub.2 Val Leu Lys Gly Asp Gly Pro Val Gln Gly Ile Ile Asn Phe Glu Gln Lys Glu Ser Asn Gly Pro Val Lys Val Trp Gly Ser Ile Lys Gly Leu Thr Glu Gly Leu His Gly Phe His Val His Glu Phe Gly Asp Asn Thr Ala Gly Cys Thr Ser Ala Gly Pro His Phe Asn Pro Leu Ser Arg Lys His Gly Gly Pro Lys Asp Glu Glu Arg His Val Gly Asp Leu Gly Asn Val Thr Ala Asp Lys Asp Gly Val Ala Asp Val Ser Ile Gle Asp Ser Val Ile Ser Leu Ser Gly Asp His X.sub.3 Ile Ile Gly Arg Thr Leu Val Val His Glu Lys Ala Asp Asp Leu Gly Lys Gly Gly Asn Glu Glu Ser Thr Lys Thr Gly Asn Ala Gly Ser Arg Leu Ala Cys Gly Val Ile Gly Ile Ala Gln (I)wherein X.sub.1 means a hydrogen atom, acetyl group or amino acid residue, X.sub.2 and X.sub.3 are either the same or different and mean individually an amino acid residue, and when X.sub.2 stands for Cys, X.sub.3 denotes an amino acid residue other than Cys.

Abstract: A peptide of the formula ##STR1## wherein A is Tyr or Phe, or a pharmaceutically acceptable salt thereof, is useful for the diagnosis of parathyroid gland function. When A is Tyr, the peptide can be labelled with iodine-125 without losing its PTH activity and without undergoing oxidation upon storage.

Abstract: A novel peptide of the formulaH--Ser--Arg--Arg--Ala--Gln--Asp--Phe--Val--Gln--Trp--Leu--Met--Asn--Thr--OHis the 16-29 fragment of glucagon and can be conjugated with a protein such as albumin or modified albumin using glutaraldehyde or 3-(2'-benzothiazolyl-dithio) propionate succinimide ester as a conjugation reagent. The conjugated peptide can be used to sensitize a mammal by administering the conjugated peptide subcutaneously, after which the blood is collected from the mammal and antibodies concentrated from the blood, which antibodies are then useful in assay methods for trace amounts of glucagon in human blood.

Abstract: A peptide of the formulaR--Lys--Lys--Glu--Asp--Asn--Val--Leu--Val--Glu--Ser--His--Glu--Lys--Ser--Le u--Gly--Glu--Ala--Asp--Lys--Ala--Asp--Val--Asp--Val--Leu--Thr--Lys--Ala--Ly s--Ser--Gln--Ohwherein R is H, H--Tyr-- or R.sub.1 --Pro--Arg--, R.sub.1 is H, H--Tyr-- or R.sub.2 --Ala--Gly--Ser--Gln--Arg--, and R.sub.

Abstract: A peptide of the formulaR-SER-LEU-PRO-SER-PRO-SER-ARG-LEU-PRO-GLY-PRO-SER-ASP-THR-PRO-ILE-LEU-PRO-G LN-OHwhereinR: H or R.sub.1 -Ser-Ser-Ser-Ser-Lys-Ala-Pro-Pro-Pro group,R.sub.1 : H or R.sub.2 -R.sub.3 -Asp-Asp-Pro-Arg-Phe-Gln-Asp group,R.sub.2 : H or R.sub.4 -Asp-His-Pro-Leu-Thr group,R.sub.4 : H-R.sub.5 -Gly-Gly-Pro-Lys group,R.sub.5 : Cys or Tyr group, andR.sub.3 : Cys or S-acetamidemethyl-Cys group,or salt thereof, has utility for the preparation of antibodies for assaying human chorionic gonadotropin or as a labelling reagent.

Abstract: Novel amine compounds of the formula ##STR1## wherein R.sub.1 is lower alkyl and R.sub.2 is substituted methyl amino or D-amino acid residue, or a salt thereof. R.sub.1 can typically be isobutyl or methyl; and R.sub.2 can be methylamino of the formula--NH--CH.sub.2 --R.sub.3in which R.sub.3 is organic, more particularly methyl, ethyl, n-propyl, isopropyl, n-butyl, amyl, p-hydroxybenzyl, 3,4-di-hydroxybenzyl, 5-imidazolemethyl, 3-imidazolemethyl or phenyl. R.sub.2 can also be D-amino acid residue of the formula ##STR2## in which one of R.sub.4 and R.sub.5 is carboxyl and the other is organic, more particularly methylthioethyl, isobutyl, methyl or phenyl, and C* is a D-asymmetric carbon atom. The compounds are useful in an assay method for leucine and aminopeptidase which comprises reacting a substrate amide as above, or a salt thereof, with a sample for leucine aminopeptidase assay, incubating the reaction product produced thereby, and measuring the thus-consumed oxygen or liberated hydrogen peroxide.

Abstract: A peptide of the formulaR--Lys--Lys--Glu--Asp--Asn--Val--Leu--Val--Glu--Ser--His--Glu--Lys--Ser--Le u--Gly--Glu--Ala--Asp--Lys--Ala--Asp--Val--Asp--Val--Leu--Thr--Lys--Ala--Ly s--Ser--Gln--OHwherein R is H, H--Tyr-- or R.sub.1 --Pro--Arg--, R.sub.1 is H, H--Tyr-- or R.sub.2 --Ala--Gly--Ser--Gln--Arg--, and R.sub.2 is H, H--Cys-- or H--Tyr--, or a salt thereof, is useful for assaying human parathyroid hormone (h-PTH).