Abstract: A complex of alpha-interferon with a monoclonal antibody complexes with the alpha-interferon without impairing its antiviral activity. The serum half-life of the interferon administered as the complex is substantially increased when compared to that of alpha-interferon administered alone.

Abstract: There are disclosed pyrylium salts and a method of using them medicinally in photodynamic therapy for increasing the survival time of animals affected with glioma or mammary carcinoma. The salts are seleno- or telluropyrylium compounds having a singlet oxygen quantum efficiency of at least 0.005 when exposed as described at wavelengths between about 650 and 1000 nanometers.

Abstract: The invention provides compounds of the general formula (I) ##STR1## wherein X represents a C.sub.1-6 alkylene, C.sub.2-6 alkenylene or C.sub.2-6 alkynylene chain andY represents a bond, or a C.sub.1-4 alkylene, C.sub.2-4 alkenylene or C.sub.2-4 alkynylene chain with the proviso that the sum total of carbon atoms in X and Y is not more than 8;Ar represents a phenyl group optionally substituted by one or more substituents selected from halogen atoms or the groups C.sub.1-3 alkyl, nitro, --(CH.sub.2)qR [where R is hydroxy, C.sub.1-3 alkoxy, --NR.sup.3 R.sup.4 (where R.sup.3 and R.sup.4 each represent a hydrogen atom, or a C.sub.1-4 alkyl group, or --NR.sup.3 R.sup.4 forms a saturated heterocyclic amino group which has 5-7 ring members and optionally contains in the ring one or more atoms selected from --O-- or --S-- or a group --NH-- or --N(CH.sub.3)--), --NR.sup.5 COR.sup.6 (where R.sup.5 represents a hydrogen atom or a C.sub.1-4 alkyl group, and R.sup.6 represents a hydrogen atom or a C.sub.1-4 alkyl, C.sub.