Described are means for the direct and continuous connection of a catheter to the lumen of any tubular anatomical structure, or ductus, without medically significant leakage. A port implanted at the body surface with piping to a periductal collar allows drug or radionuclide delivery that bypasses the upstream lumen. The port allows injection, infusion, aspiration, or attachment of an automatic ambulatory pump. A superparamagnetic nanoparticle carrier-bound drug, for example, can be introduced into the lumen to pass downstream until the particles, with or without the drug still bound, are drawn into the lumen wall by a magnetized jacket surrounding the ductus. Such constitutes a method of drug targeting whereby a segment of a vessel or the territory supplied by a branch of that segment can be circumscribed for exposure to the drug. A jacket with side-entry connector positioned in surrounding relation to a lesion requiring treatment can itself be magnetized.