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81.
PURPOSE: The presence of similar histologic subtypes of epithelial ovarian and endometrial cancers has long been noted, although the relevance of this finding to pathogenesis and clinical management is unclear. Despite similar clinical characteristics, histologic subtypes of cancers of the ovary and endometrium are treated according to organ of origin. This study compares the gene expression profiles of analogous histologic subtypes of cancers of the ovary and endometrium using the same genomic platform to determine the similarities and differences between these tumors. EXPERIMENTAL DESIGN: Gene expression profiles of 75 cancers (endometrioid, serous, and clear cell) of the ovary and endometrium, five renal clear cell cancers, and seven normal epithelial brushings were determined using a 11,000-element cDNA array. All images were analyzed using BRB ArrayTools. Validation was done using real-time PCR on select genes and immunohistochemical staining. RESULTS: Comparison across endometrial and ovarian cancers and serous and endometrioid tumors showed expression patterns reflecting their organ of origin. Clear cell tumors, however, showed remarkably similar expression patterns regardless of their origin, even when compared with renal clear cell samples. A set of 43 genes was common to comparisons of each of the three histologic subtypes of ovarian cancer with normal ovarian surface epithelium. CONCLUSIONS: The comparison of the gene expression profiles of endometrioid and serous subtypes of ovarian and endometrial cancer are largely unique to the combination of a particular subtype in a specific organ. In contrast, clear cell cancers show a remarkable similarity in gene expression profiles across organs (including kidney) and could not be statistically distinguished.  相似文献   
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The calcifying epithelial odontogenic tumor (CEOT), or Pindborg tumor, is a rare and benign odontogenic neoplasm that affects the jaw. The most common manifestation of CEOT is a unifocal or localized lesion of the involved jaw, which may appear clinically as a hard tissue swelling and radiographically as a mixed radiolucent-radiopaque mass. In this article, we present a unique case of CEOT affecting multiple sites in the maxilla and mandible of a 51-year-old white man. Though biopsy samples from all involved sites revealed similar histopathologic features consistent with CEOT, the fact that there was a multifocal presentation is an unusual phenomenon for CEOT and has never been reported. Multifocal odontogenic lesions are not typical but have been observed in conditions associated with known genetic mutations. For example, multiple odontogenic keratocysts are the most common feature of the inherited condition known as nevoid basal cell carcinoma syndrome. This case, however, is the first one to demonstrate that there may be a multifocal variant of CEOT that has not been previously recognized.  相似文献   
84.
RATIONALE: Holocaust survivors, who experienced trauma 60 years ago, provide an opportunity to explore the impact of early lifetime trauma in later life and, in particular, the interplay of depression and posttraumatic stress disorder (PTSD). In this study, the authors contrast depressed Holocaust survivors (HD), nondepressed Holocaust survivors (HND), and older depressed persons (CD). METHODS: The sample consisted of 36 consecutive Holocaust survivors (mean age: 79 years) treated in a primary care practice, among whom 20 (56%) were diagnosed as having a major depressive disorder and 16 as nondepressed; 18 depressed non-Holocaust Jewish primary care patients served as controls (mean age: 84 years). The authors examined nine clinical and social variables. The Kruskal-Wallis, Mann-Whitney U, and chi(2) tests were used to contrast the groups. The authors used a conservative significance level of .01. RESULTS: In contrast to the CD group, the HD group was significantly older, more likely to report PTSD and guilt symptoms, to have higher Beck Anxiety Inventory (BAI) and Brief Psychiatric Rating Scale (BPRS) scores, and to have more impaired social functioning. In contrast to the HND group, the HD group was significantly more likely to report PTSD and guilt feelings, to have higher Hamilton Depression Scale (HAM-D), BAI, and BPRS scores, and to have more impaired social functioning. In contrast to the CD group, the HND group was significantly more likely to have PTSD symptoms and to have lower HAM-D and BPRS scores. CONCLUSIONS: The prevalence of depression and PTSD symptoms were very high among survivors. Depressed survivors had significantly worse psychologic and social functioning than depressed controls. Depressed survivors had more PTSD symptoms than nondepressed survivors, although it is unclear as to the causal direction of the relationship between depression and PTSD.  相似文献   
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On May 8–10, 1995, a workshop on chronic inhalation toxicity and carcinogenicity testing of respirable fibrous particles was held in Chapel Hill, North Carolina. The workshop was sponsored by the Office of Pollution Prevention and Toxics, U.S. Environmental Protection Agency (EPA), in collaboration with the National Institute of Environmental Health Sciences (NIEHS), the National Institute for Occupational Safety and Health (NIOSH), and the Occupational Safety and Health Administration (OSHA). The goal of the workshop was to obtain input from the scientific community on a number of issues related to fiber testing. Major issues for discussion were: (i) the optimal design and conduct of studies of the health effects of chronic inhalation exposure of animals to fibers; (ii) preliminary studies which would be useful guides in designing the chronic exposure study; (iii) mechanistic studies which would be important adjuncts to the chronic exposure study to enable better interpretation of study results and extrapolation of potential effects in exposed humans; and (iv) available screening tests which can be used to develop a minimum data set for (a) making decisions about the potential health hazard of the fibers and (b) prioritizing the need for further testing in a chronic inhalation study. After extensive discussion and debate of the workshop issues, the general consensus of the expert panel is that chronic inhalation studies of fibers in the rat are the most appropriate tests for predicting inhalation hazard and risk of fibers to humans. A number of guidances specific for the design and conduct of prechronic and chronic inhalation studies of fibers in rodents were recommended. For instance, it was recommended that along with other information (decrease in body weight, systemic toxicity, etc.), data should be obtained on lung burdens and bronchoalveolar lavage fluid analysis to assist in establishing the chronic exposure levels. Lung burden data are also important for quantifying aspects of risk assessment related to dosimetric adjustments before extrapolation. Although mechanistic studies are not recommended as part of the standard chronic inhalation studies, the expert panel stressed the need for obtaining mechanistic information as far as possible during the course of subchronic or chronic inhalation studies. At present, no single assay and battery of short-term assays can predict the outcome of a chronic inhalation bioassay with respect to carcinogenic effects. Meanwhile, several short-termin vitroandin vivostudies that may be useful to assess the relative potential of fibrous substances to cause lung toxicity/carcinogenicity have been identified.  相似文献   
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It is not a question of dying earlier or later, but of dying well or ill, and dying well means escape from the danger of living ill. (Seneca, 4 BC)  相似文献   
89.
Alcoholic patients often have impaired immune function, yet little is known about the precise mechanism(s) of this impairment. We have previously shown that ethanol consumption by mice alters copolymer-specific humoral and cellular immune responses. In this study, we asked whether alcohol consumption by mice would phenotypically alter lymphocyte populations. Female C57BL/6 mice were fed a nutritionally complete liquid diet containing 35% ethanol-derived calories for up to 8 days. As controls, mice either were fed a liquid control diet that isocalorically substitutes sucrose for ethanol or remained on a standard solid diet and water ad libitum. Although mice fed ethanol-containing liquid or pair-fed control liquid diets have decreased numbers of spleen cells compared with solid diet controls, only the ethanol-containing diet allowed normally nonresponder C57BL/6 spleen cells to make antibody responses to the poly(Glu50Tyr50) synthetic copolymer antigen. Flow cytometric analysis of splenic lymphocyte populations of mice on the ethanol-containing diet shows an increase in the relative proportion of T-lymphocytes as compared with mice on either solid or liquid control diets. No such change is seen for either B-cell or natural killer cell populations in these same mice. Both liquid control and liquid ethanol diets caused a slight decrease in the CD4:CD8 ratios of splenic T-lymphocytes. We see the relative percentage of T-cells bearing the αβ-cell receptor (TcR) increases in the spleens of liquid ethanol diet mice; a smaller increase TcRαβ usage is seen in the spleens of liquid control mice, compared with solid diet mice. Flow cytometric analysis shows that little, if any, difference exists in TcRγδ expression between the liquid ethanol and either the liquid control or solid diet groups. Preliminary analysis of TcRαβ subsets suggest that ethanol increases the percentage of T-cells expressing Vβ5 and Vβ8, and decreases the percentage of Vβ11 expressing cells. These findings suggest that, in addition to modifying the immune response, ethanol alters the phenotypic expression of lymphocyte subsets.  相似文献   
90.
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