Abstract: The present invention provides a shielding member for radioactive substances which can be made compact in size and light in weight while maintaining its shielding ability, or improves the shielding ability while keeping the same size, thereby to store a large volume of radioactivity. At the same time, the present invention provides a manufacturing method for the above shielding member and a radioactive solution-producing apparatus using the above shielding member. The radioactive substance-shielding member uses two or more kinds of radiation shielding materials of different shielding abilities. A shielding body made of a shielding material of the highest shielding ability is arranged at an area which is the nearest to a radioactive source.

Abstract: A sheath for a syringe barrel, includes a main body in which a radiation shielding device for holding a syringe filled with pharmaceutical liquid therein is fitted, a male luer provided at a front end of the main body and designed to set a disposable needle, and a transfixing needle extending backward from inside of the male luer to penetrate a rubber plug at an opening at a front end of a syringe held in the main body.

Abstract: A process for preparing a radiopharmaceutical composition comprising a technetium 99m chelate complex, comprises the steps of:(1) mixing (a) HSCH.sub.2 CO--NHCH.sub.2 CO--NHCH.sub.2 CO--NHCH.sub.2 COOH (mercaptoacetylglycylglycylglycine, MAG3), (b) a watersoluble reducing agent, (c) a water-soluble stabilizing agent in an amount of not less than 70 mol per 1 mol of the water-soluble reducing agent and (d) a pertechnetate at a pH of about 8 to 11; and(2) heating the resultant mixture at a temperature of about 90 to 140.degree. C.Said process removes any troublesome labeling operation at the diagnostic site and relieve the practitioners from the exposure to radiation during the labeling operation.

Abstract: A polyaminedithiol compound of the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.11 and R.sub.12 are each a lower alkyl group, R.sub.21 is a hydrogen atom or a lower alkyl group, and R.sub.3 and R.sub.13 are each a hydrogen atom or a nitrogen-containing organic group, provided that at least one of R.sub.3 and R.sub.13 is a nitrogen-containing organic group, which is used for imaging of the regional cerebral blood flow.