Search PubMed⌕ Search

Biomedical subjects

C Hammer

Publications and source records attributed to C Hammer.

At least 271 records · Page 15Linked to original sources
PubMed1977

[The influence of humoral immune mechanisms on metastasizing tumors in humans (author's transl)].

Long-continued stimulation of the immune system by chronic infections or tumors leads to dysfunction of the immunoregulation. Different types of antibody, anti-antibody and immunocomplex point to the fact that it is not a matter of the weakening of the patient's immune defense but that these antibodies are important regulating mechanisms for the immune system. While antibodies directed against a tumor have a useful function for the patient with dissemination of metastasizing tumors, the anti-antibodies and antigenotypic antibodies represent a counterregulation which, in the advanced stage of the disease, eliminates the initial control.

Antibodies, Anti-Idiotypic↗
PubMed1976

[Long-term graft survival in the xenogeneic system wolf-dog (author's transl)].

In contrast to the zoological definition that wolf and dog belong to different species, it is shown by this study that in terms of immunology both species appear to be even closer related than DL-A compatible and MLC negative unrelated dogs. However, this close relationship is not expressed in DL-A or MLC tissue typing. Wolf skin-graft survival time in untreated dogs was 12,5, in ALG-treated dogs 85,6 days. The survival time in this system may be less dpendent on DL-A or MLC histocompatibility than on other genetic systems, which are hitherto not sufficiently defined. An accidental, speciesspecific accordance in these systems may explain the obviously weak histocompatbility barrier between wolf and dog. It is concluded that in certain species-combinations xenotransplantation could be more successful than random allotransplantation. The availability of a xenogeneic species related to man similar as wolf to dog would markedly facilitate clinical xenotransplantation.

Animals↗
PubMed1975

Xenogeneic skin and kidney transplants in a closely related canine system, fox-dog.

Fox kidney and skin grafts were transplanted into dog recipients. Fox kidneys, transplanted en bloc into untreated dogs, survived 6.2 +/- 0.4 days. The skin transplants survived 5.9 +/- 1.4 days. The grafted kidneys showed almost normal function before rejection. Both skin and kidney rejection were mediated through a cellular mechansim. Performed natural antibodies against donor tissue were not present in the serum of the recipients. These results combined with absorption studies suggested a close relationship between fox and dog, but different number and morphology of chromosomes, immunoelectrophoretic patterns of serum proteins, and disparities of the transplantation antigens proved that the fox is a species quite separate from the dog. It was concluded that the fox-dog system, with its similarity to the chimpanzeeman relationship, offers a unique model to study clinically applicable methods of managing xenografts between closely related species.

Animals↗