ISSN:0098-4108    

DOI:10.1080/15287397909529740

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

ISSN:0098-4108    

DOI:10.1080/15287397909529741

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

An appraisal is made of these chemical carcinogens available in the human environment that have been implicated in the etiology of liver cancer. The possible role of mycotoxins is discussed in detail, in particular the association between the aflatoxins and liver cancer in Africa and the Far East.

ISSN:0098-4108    

DOI:10.1080/15287397909529742

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Pesticides are biologically active substances that are significant environmental contaminants. Only a few of the many pesticides have been subjected to short‐ or long‐term carcinogenicity tests. To date, 16 of them have been identified as hepatocarcinogenic agents in animals, usually mice. However, their cancer‐inducing effect in humans has not been completely proved. The use of short‐term screening tests (first of all the Salmonella‐microsome test) for routine screening of pesticides on a large scale is highly recommended.

ISSN:0098-4108    

DOI:10.1080/15287397909529743

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Two edible mushrooms are known to contain hydrazine analogs. The wild false morel Gyromitra esculenta contains up to 0.3% acetaldehyde methylformylhydrazone and N‐methyl‐N‐formylhydrazine (MFH). The latter chemical, under certain conditions, also yields methylhydrazine. The commonly eaten, cultivated mushroom Agaricus bisporus contains up to 0.04% β‐N‐[γ‐L(+)‐glutamyl]‐4‐hydroxymethylphenylhydrazine and 4‐hydroxymethylphenylhydrazine. MFH was administered in drinking water continuously for life to Swiss mice and Syrian (golden) hamsters. In both species the compound induced high incidences of benign and malignant hepatocellular neoplasms. Also, methylhydrazine given orally induced a significant incidence of malignant histiocytomas in the livers of hamsters. The N'‐acetyI derivative of 4‐hydroxymethylphenylhydrazine administered orally to mice gave rise to lung tumors and blood vessel tumors, mainly in the liver. Furthermore, these three compounds produced tumors in various other tissues. Histopathologically, the tumors were classified as benign hepatomas, liver cell carcinomas, angiomas and angiosarcomas of blood vessels, and adenomas and adenocarcinomas of lungs. From representative samples of these neoplasms detailed transmission electron microscopic investigations were also carried out. Since these hydrazine analogs induce tumors in animals and these mushrooms are consumed on a large scale by humans in various parts of the world, their hazardous nature should be considered.

ISSN:0098-4108    

DOI:10.1080/15287397909529744

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Corticosterone inhibits proliferation of rat liver cells, but it can be inactivated by blocking its cytoplasmic receptors in liver cells with other steroids (progesterone). High levels of progesterones in animals lead to stimulated proliferation in the liver. Abnormally high proliferation in the liver may promote malignant transformation or may make it possible for smaller amounts of hepatocarcinogenic substances to induce tumors in a shorter time than normal.

ISSN:0098-4108    

DOI:10.1080/15287397909529745

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Experience with pathological material from 150 women with liver tumors is reviewed. The features of liver cell adenoma and focal nodular hyperplasia are sufficiently different that the vast majority of the benign tumors can be easily subclassified. Although most occurred in women ingesting steroids, the wide usage of oral contraceptives makes it difficult to prove a causative role. Nineteen of the tumors were malignant and, to date, 12 of those patients have died of their disease. Since hepatomas are much more common than benign liver tumors, one must be even more circumspect in indicting steroids in their causation. In this group of women none had cirrhosis, whereas in the general population cirrhosis is a very common precedent lesion. Further investigation of estrogens and primary liver carcinoma would be timely.

ISSN:0098-4108    

DOI:10.1080/15287397909529746

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Since the introduction of oral contraceptive steroids in 1960 there has been a sharp increase in the incidence of benign liver tumors. Epidemiologic and other evidence links focal nodular hyperplasia and hepatic cell adenoma to the use of these agents. The risk increases with long‐term exposure. The majority of patients were less than 35 years old. Most patients were exposed to mestranol (ME) alone or alternately with ethinylestradiol, both synthetic steroidal estrogens. Inability to demethylate ME in the smooth endoplasmic reticulum of hepatocytes may allow massive accumulation of oncogenic metabolites. This is probably a pharmacogenetic variable in a small number of women. Cholestasis, hypervascularity, induction of intracellular enzyme systems, thrombogenesis, and thickening of arterial and venous walls are other known effects of synthetic estrogens and progestogens. All may contribute to the pathogenesis of liver tumors.

ISSN:0098-4108    

DOI:10.1080/15287397909529747

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The American College of Surgeons’ survey data on 378 female and 165 male cases of primary liver tumors reported by 477 hospitals in the United States during 1970–1975 are presented. In males, 91.5% of the tumors were malignant, confirming the rarity of benign liver tumors in males. Among females, 43.9% were malignant and 56.1% were benign. Of the 212 benign tumors, 96 were hepatic cell adenomas and 58 were focal nodular hyperplasias. A positive history of oral contraceptive use was found in nearly half of all tumors, 65% of benign tumors, 74% of hepatic cell adenomas, and 74% of focal nodular hyperplasias. High frequencies of benign tumors were observed in the age group 20–30 yr. More than 80% of the tumors in this age group were found in oral contraceptive users. Symptomatology was more severe among users. No case of intraperitoneol bleeding was observed in nonusers. The findings confirm the suggested association between use of oral contraceptives and hepatic cell adenomas and focal nodular hyperplasias.

ISSN:0098-4108    

DOI:10.1080/15287397909529748

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

There is an excess prevalence of markers of active infection with hepatitis B virus in patients with primary liver cancer in many parts of the world. Early age of infection with hepatitis B virus is likely to be an important factor, resulting in persistent infection that may progress to chronic liver damage. Results of recent experimental studies are consistent with integration of hepatitis B viral DNA with host cell DNA molecules. It is likely that primary liver cancer is the cumulative result of several cofactors including infection with hepatitis B virus; genetic, immunologic, hormonal, and nutritional factors; and environmental factors including mycotoxins and chemical carcinogens.

ISSN:0098-4108    

DOI:10.1080/15287397909529749

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor