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A mixed‐method study of effects of a therapeutic play intervention for children on parental anxiety and parents' perceptions of the intervention
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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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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 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
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