摘要:

Antisera were prepared in rabbits against urea-extractable proteins of normal mouse epidermis, papillomas, and squamous-cell carcinomas. The relationship of these antisera and the antigens of the three tissues was studied by immunodiffusion in agar before and after inhibition treatment of these antisera with the three antigens. These procedures revealed that (1) the epidermis has urea-extractable antigens which are present in much smaller amounts in the urea extracts of papillomas and squamous-cell carcinomas, and (2) papillomas and carcinomas have several urea-extractable antigens in common, and both the benign and malignant growths each have at least one antigen present in greater amount in one tissue than in the other. The papilloma and carcinoma antigens are present, but in small amounts in normal epidermis.

ISSN:0030-2414    

DOI:10.1159/000224533

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

All untreated rat sera inhibited hemagglutination of RV and L-S strain of rat virus in high titers. Treatment of rat sera by heat or KIO4 did not remove hemagglutination inhibitors, while kaolin was effective. However, neutralization titers were even lower than H-I titers with kaolin-treated sera. Neutralization tests differentiated between antibodies against the two viral strains. Four strains of rats varied in the percentage of animals with antibodies against rat virus from 0–100%, and these findings are compared with spontaneous tumor rates. Seventy-eight percent of Wistar rats with spontanous adenomata, benign cysts, or X-ray-induced tumors had antibody against one or both viruses, while sera from none of the animals with transplanted tumors exhibited antibody. In Marshall rats, which were shown to be antibody-free, RV caused a lethal infection when injected into newborns within 6–8 days, while the L-S strain caused only 42% deaths in 13–60 days. Injection of older animals resulted in production of antibodies but no signs of disease. None of the animals developed tumors after inoculation with rat viruses. The similarities between the properties and behavior of these viruses to known oncogenic viruses are disc

ISSN:0030-2414    

DOI:10.1159/000224534

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

The factor responsible for the prolonged survival of skin grafts taken from mice bearing Ehrlich ascites tumor (EAT), was investigated in this study. It could be demonstrated that the prolonged survival is not confined only to the grafts taken from mice injected previously with full EAT. Grafts taken from mice inoculated with EAT cells separated from the supernatant by centrifugation, or from mice inoculated with the supernatant only, has also a prolonged survival. Treatment of EAT with ultrasonics prior to its inoculation to the donor, was followed by a shorter survival of the graft though this was still longer than that in the control group.

ISSN:0030-2414    

DOI:10.1159/000224535

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Nine adults with acute myeloblastic leukemia were treated with L-asparaginase, a new anti-neoplastic agent. One of these patients achieved a complete remission. This case is presented in detail including serial determinations of serum L-asparaginase levels during the treatment. The mechanism of action, toxicology and the present status of the effectiveness of L-asparaginase in acute leukemia are presented. Optimal dose schedule and possible future role of L-asparaginase in the treatment of leukemia is discussed.

ISSN:0030-2414    

DOI:10.1159/000224536

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

This study brings forth evidence in support of the existence of a direct relationship between antimitotic activity and the alteration of some enzymatic systems (NADH and NADPH tetrazolium reductase, LDH, SDH, MDH, IDH and cis-aconitase) which is produced by the administration of the methylhydrazine derivative Natulan® in both Ehrlich ascites carcinoma and N-13 ascites hepatoma. The greatest level of antimitotic activity occurred 8 h after the administration of 300 mg/kg of the preparation and was accompanied by a decrease in the activity of the systems of enzymes studied in the Ehrlich ascites carcinoma. This decrease could be observed by the application of histochemical methods. Twenty four hours after the experiment had begun, total metabolic and divisional recuperation had taken place in the Ehrlich ascites carcinoma. At the same time, there was intense reactivation of the enzymes examined in N-13 ascites hepatoma. In addition, this tumor presented a pronounced retention of glycogen

ISSN:0030-2414    

DOI:10.1159/000224537

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Lymphosarcoma-bearing spleen fragments or cell-free extracts from an amphibian (Xenopus laevis laevis) implanted or injected into cockroaches (Periplaneta americana) elicited a characteristic hemocytic reaction. Back-transfer of the abnormal insect tissue to immature Xenopus up to 125 days after implantation led to the development of lymphoid tumors in the toads, thus indicating retention of infectivity during passage through the insect.

ISSN:0030-2414    

DOI:10.1159/000224538

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

This study shows that streptomycin has both the non-specific effect, short of toxicity, of disrupting developmental sequences in larval anurans and the phase specific effect of altering tail fin regeneration. Streptomycin seems to inhibit regeneration of mesenchymal elements while leaving ectodermal components able to proliferate though in quantitatively different amounts. It appears, therefore, that the regressive, histolytic stages of regeneration are not significantly affected by streptomycin, but the phases of cytoredifferentiation of muscle and connective tissue amounts and the regulation of somite pattern are progressively curtailed with exposure to the drug.

ISSN:0030-2414    

DOI:10.1159/000224539

出版商:S. Karger AG    

年代:1970

数据来源: Karger

ISSN:0030-2414    

DOI:10.1159/000224540

出版商:S. Karger AG    

年代:1970

数据来源: Karger