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Astrid Ruiz-Marg in Berenice M Rom n-Calleja Paulina Moreno-Guill n Jos A Gonz lez-Regueiro Deyanira K sulas-Delint Alejandro Campos-Murgu a Nayelli C Flores-Garc a Ricardo Ulises Mac as-Rodr guez 《World journal of gastrointestinal oncology》2021,13(10):1440-1452
Hepatocellular carcinoma (HCC) is the most frequent primary liver cancer and presents together with cirrhosis in most cases. In addition to commonly recognized risk factors for HCC development, such as hepatitis B virus/hepatitis C virus infection, age and alcohol/tobacco consumption, there are nutritional risk factors also related to HCC development including high intake of saturated fats derived from red meat, type of cooking (generation of heterocyclic amines) and contamination of foods with aflatoxins. On the contrary, protective nutritional factors include diets rich in fiber, fruits and vegetables, n-3 polyunsaturated fatty acids and coffee. While the patient is being evaluated for staging and treatment of HCC, special attention should be paid to nutritional support, including proper nutritional assessment and therapy by a multidisciplinary team. It must be considered that these patients usually develop HCC on top of long-lasting cirrhosis, and therefore they could present with severe malnutrition. Cirrhosis-related complications should be properly addressed and considered for nutritional care. In addition to traditional methods, functional testing, phase angle and computed tomography scan derived skeletal muscle index-L3 are among the most useful tools for nutritional assessment. Nutritional therapy should be centered on providing enough energy and protein to manage the increased requirements of both cirrhosis and cancer. Supplementation with branched-chain amino acids is also recommended as it improves response to treatment, nutritional status and survival, and finally physical exercise must be encouraged and adapted to individual needs. 相似文献
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The use of the monoclonal antibody Ki-67 in the identification of proliferating cells: application to surgical neuropathology 总被引:6,自引:0,他引:6
In order to test its potential application to surgical neuropathology, the monoclonal antibody Ki-67 was used to demonstrate immunohistochemically the proliferating cells in 40 neoplasms of the nervous system. The antibody, which reacts with a nuclear protein expressed in the G1, G2, S, and M phases of the cell cycle, was demonstrated in frozen sections of all lesions. The highest incidence of stained nuclei was found in a metastatic carcinoma (57%). The percentage of stained cells in gliomas was in general agreement with the histologic grade and known biologic behavior of the lesions, ranging from 0.6% in a pilocytic astrocytoma to 12.4% in a glioblastoma multiforme. In the fibrillary astrocytic neoplasms of low cellularity, there were good correlations between the percentages of stained cells and the degrees of nuclear pleomorphism and chromatin density. In meningiomas, schwannomas, and a cerebellar hemangioblastoma, the fractions of labeled nuclei were less than 1%. The percentage of stained cells in pituitary adenomas showed considerable variation among the four cases (0.2-1.5%), the biologic significance of which is unknown. In four of the above cases, Ki-67 staining was performed on air-dried squash preparations with excellent visualization of immunoreactive nuclei. In one case, a hemangioblastoma, no stained nuclei were seen. The results confirm that Ki-67 staining is technically suitable as a diagnostic method, with good correlations between frozen sections and smear preparations. Determination of the replicating cell fraction could become an important additional criterion to predict the biologic behavior of nervous system neoplasms. 相似文献
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A. M. Raschke A. E. C. Burger 《Archives of environmental contamination and toxicology》1997,32(1):42-49
A preliminary study undertaken by the CSIR in July 1993
on the health effects of aerial crop spraying of pesticides in the Vaalharts
irrigation area in South Africa indicated that potential health risks could
exist for the inhabitants of this area. An extensive scientific health risk
assessment and epidemiological study to determine the actual health risks, is
very expensive and requires medical and financial justification. The aim of
this study was to develop a theoretical health risk model, which could be
used as a predictive tool to determine as accurately as possible from the
data available if a complete scientific health risk assessment study is
justified. The actual amounts of pesticides sold in the Vaalharts area by two
major pesticide manufacturers were used to perform a theoretical health risk
assessment. The risks were assessed by making use of RISK*ASSISTANT, a
computer modeling system and chemical database. The United States
Environmental Protection Agency's (EPA) health risk model was applied to
the data to identify the hazards, assess the exposures and dose response, and
characterize the risks. Three exposure scenarios, namely, the ingestion of
food and water and the inhalation of air were evaluated. The method used to
calculate the risks varied according to the type of health hazard and the
results were characterized accordingly. The acute health effects due to
exposure to pesticides are well known and the risks are easy to determine.
However, the risks associated with chronic health hazards were more difficult
to calculate. For this reason a ranking model was developed which made use of
a point scoring system. This model highlights those pesticides which have the
greatest possibility of causing chronic health effects. From the results it
can be concluded that very large amounts of pesticides are used in the
Vaalharts area and that the community might be at risk to chronic health
effects. Although the theoretical health risk assessment model was
successfully used in this study, its effectiveness as a predictive tool still
has to be proven by a complete scientific study.
Received: April 1996/Revised: 21 July 1996 相似文献
10.
M J Coppes M F Tournade J Lemerle S Weitzman A Rey D Burger M Carli P A Vo?te 《Cancer》1992,69(11):2721-2725
The International Society of Pediatric Oncology (SIOP) recommends preoperative treatment in the management of eligible patients with Wilms' tumor. Until 1980, children younger than 12 months of age (infants) at diagnosis had been excluded from the SIOP trials. SIOP 6, conducted from 1980 to 1987, was the first SIOP study to include infants older than 6 months of age. This retrospective analysis of 145 infants registered to SIOP 6 demonstrates that in infants older than 6 months and having favorable histology (FH), a two-drug preoperative chemotherapy (CT) regimen of 4 weeks significantly ameliorated stage distribution as determined at delayed surgery but did not affect a good outcome. However, the CT dose utilized in SIOP 6 resulted in an unacceptable toxicity in this age group, and SIOP 9, the new SIOP study of Wilms' tumor, recommends a reduced dose of CT in infants. Preoperative CT is not recommended in infants younger than 6 months of age. Specifically, the high incidence (29%) of mesoblastic nephroma in this age group does not justify such an approach. Histopathologic diagnosis should be obtained in these patients before any treatment. 相似文献