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91.
William K. Boyes Brittany Lila M. Thornton Souhail R. Al-Abed Christian P. Andersen Dermont C. Bouchard Robert M. Burgess 《Critical reviews in toxicology》2017,47(9):771-814
Engineered nanomaterials (ENM) are a growing aspect of the global economy, and their safe and sustainable development, use, and eventual disposal requires the capability to forecast and avoid potential problems. This review provides a framework to evaluate the health and safety implications of ENM releases into the environment, including purposeful releases such as for antimicrobial sprays or nano-enabled pesticides, and inadvertent releases as a consequence of other intended applications. Considerations encompass product life cycles, environmental media, exposed populations, and possible adverse outcomes. This framework is presented as a series of compartmental flow diagrams that serve as a basis to help derive future quantitative predictive models, guide research, and support development of tools for making risk-based decisions. After use, ENM are not expected to remain in their original form due to reactivity and/or propensity for hetero-agglomeration in environmental media. Therefore, emphasis is placed on characterizing ENM as they occur in environmental or biological matrices. In addition, predicting the activity of ENM in the environment is difficult due to the multiple dynamic interactions between the physical/chemical aspects of ENM and similarly complex environmental conditions. Others have proposed the use of simple predictive functional assays as an intermediate step to address the challenge of using physical/chemical properties to predict environmental fate and behavior of ENM. The nodes and interactions of the framework presented here reflect phase transitions that could be targets for development of such assays to estimate kinetic reaction rates and simplify model predictions. Application, refinement, and demonstration of this framework, along with an associated knowledgebase that includes targeted functional assay data, will allow better de novo predictions of potential exposures and adverse outcomes. 相似文献
92.
93.
94.
The Cognitive Skills Program at the Albert Einstein College of Medicine has identified 1% to 2% of students from several classes whose learning disabilities were previously undiagnosed. In three case studies, the importance of early identification and support during the preclinical years—and the impact of diagnosis, evaluation, and intervention—are illustrated. In each case, there was a dramatic improvement in performance when the student was made aware of his or her learning disability and when appropriate intervention was provided. 相似文献
95.
96.
A Psyrri P Kountourakis Z Yu C Papadimitriou S Markakis R L Camp T Economopoulos M A Dimopoulos 《Annals of oncology》2007,18(4):709-715
BACKGROUND: p53 protein is regarded as a valuable prognostic marker in cancer with a potential use as a molecular target. Here, we sought to determine the prognostic value of p53 in ovarian cancer using a novel method of compartmentalized in situ protein analysis. PATIENTS AND METHODS: A tissue array composed of 141 advanced stage ovarian cancers uniformly treated was constructed. For evaluation of p53 protein expression, we used an immunofluorescence-based method of automated in situ quantitative measurement of protein analysis (AQUA). RESULTS: High nuclear p53 expression levels were associated with better outcome for overall survival (OS) (P = 0.0023) and disease-free survival (P = 0.0338) at 5-years. High cytoplasmic p53 expression levels were associated with better outcome for OS (P = 0.0002). In multivariable analysis, high nuclear and high cytoplasmic p53 level with International Federation of Gynecology and Obstetrics (FIGO) stage were the most significant predictor variables for OS and high nuclear p53 level with FIGO stage were the significant predictor variables for disease-free survival. CONCLUSIONS: Assessment of the prognostic value of p53 protein levels using conventional immunohistochemistry is limited by the nonquantitative nature of the method. AQUA provides precise estimation of p53 protein levels and was able to elucidate the association of p53 protein levels and ovarian cancer prognosis. 相似文献
97.
Brenner DS Jacobs SC Drachenberg CB Papadimitriou JC 《Archives of pathology & laboratory medicine》2000,124(10):1553-1556
A 69-year-old woman presented with a large left retroperitoneal suprarenal mass. Radical resection of the left kidney and the mass revealed a cystic adrenal tumor with a weight of 1500 g. Histologic examination showed that the cyst was composed mostly of partially organized clotted blood. The periphery of the mass consisted of a thin rim of cortical and medullary adrenal tissue with superimposed granulomatous chronic inflammation. The infectious nature of the process was manifested by the scattered intracellular and extracellular Leishmania amastigotes that were found throughout the lesion. The differential diagnosis of cystic adrenal masses and the unusual presentation of visceral leishmaniasis are discussed in this context. 相似文献
98.
99.
A Papadimitriou M Urena G Hamill R Stanhope A D Leiper 《Archives of disease in childhood》1991,66(6):689-692
Growth hormone was given to 13 children (nine boys, four girls) with acute leukaemia who had undergone treatment with cyclophosphamide and total body irradiation before bone marrow transplantation. Mean age at total body irradiation and bone marrow transplantation was 9.0 years (range 3.7-15.8). Endocrinological investigation was carried out at a mean of 2.0 years (range 0.4-4.0) after bone marrow transplantation. Peak serum growth hormone responses to hypoglycaemia were less than 10.0 micrograms/l (less than 20.0 mU/l) in 10, 10.5 micrograms/l (21.0 mU/l) in one, greater than 16.0 micrograms/l (greater than 32.0 mU/l) in two patients. Mean age of the patients at the start of growth hormone treatment was 12.2 years (range 5.8-18.2). The mean time between total body irradiation and bone marrow transplantation and the start of growth hormone treatment was 3.2 years (range, 1.1-5.0). Height velocity SD score (SD) increased from a mean pretreatment value of -1.27 (0.65) to + 0.22 (0.81) in the first year, +0.16 (1.11) in the second year, and +0.42 (0.71) in the third year of treatment. Height SD score (SD) changed only slightly from -1.52 (0.42) to -1.50 (0.47) in the first year, to -1.50 (0.46) in the second year, and -1.74 (0.92) in the third year. Measurement of segmental proportions showed no significant increase in subischial leg length from -0.87 (0.67) to -0.63 (0.65) in the first year, to -0.58 (0.70) in the second year, and -0.80 (1.14) in the third year of treatment. Our data indicate that children who have undergone total body irradiation and bone marrow transplantation respond to treatment with growth hormone in either of two dose regimens, with an increase in height velocity that is adequate to restore a normal growth rate but not to ''catch up'', and that total body irradiation impairs not only spinal but also leg growth, possibly by a direct effect of irradiation on the epiphyses and soft tissues. 相似文献
100.
M Chrysostomou G Akalestos S Kallistros V Papadimitriou S Nazar G Chronis 《Acta obstetricia et gynecologica Scandinavica》1991,70(6):441-444
The reported incidence of adenomyosis based on unselected hysterectomies varies so widely that conclusions regarding the influence of any factor on that incidence are difficult to reach, although the relation of adenomyosis uteri to endometrial carcinoma has been the subject of only a few studies. In a 5-year period at the General Hospital of Athens, 646 hysterectomies were performed. All data were retrieved from the surgical pathology laboratory files concerning adenomyosis uteri with either simultaneous endometrial carcinoma or endometrial hyperplasia. A control population was selected from patients operated upon for a variety of benign pelvic diseases. Adenomyosis was found in association with endometrial carcinoma in 17.5% of 40 cases, and in association with endometrial hyperplasia in 21.6% of 60 cases. The control series of 546 patients had a 26% incidence of adenomyosis. The results of our study do not indicate any correlation between adenomyosis uteri and endometrial carcinoma. 相似文献