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31.
32.
Imaging is central to anatomic pathology. The captured images are used for documentation, archiving, teaching, and publication. The advent of low-cost, consumer-type, high-end digital cameras has provided a convenient, easy-to-use alternative for routine image acquisition. The various applications for digital image acquisition in anatomic pathology include, among others, digitizing conventional photographs, digital gross photography and digital macrophotography, digitizing radiographic images, and digital photomicrography. This article reviews digital image acquisition in the anatomic pathology setting using a consumer-type digital camera. The camera type chosen as an example for the discussion was selected for its popularity and wide use among pathologists and for its potential to function as a sole image input device in all applications combined. Techniques and accessories to further increase the functionality of the camera and help overcome some of the commonly encountered problems in some applications are described. 相似文献
33.
Meghna R Adhvaryu Narshimha Reddy Minoo H Parabia 《African journal of traditional, complementary, and alternative medicines》2008,5(4):409-418
The anti-tumor activity and chemopreventive potential of four Ayurvedic herbs viz. Curcuma longa L., Ocimum sanctum L., Tinospora cordifolia (Wild) Miers ex Hook.f & Thomas and Zizyphus mauritiana Lam. were evaluated using Dalton Lymphoma ascites (DLA) tumor model in Swiss Albino mice. The outcome was assessed using survival time, peritoneal ascitic fluid (Tumor volume) and hematological indices as parameters. Animals were divided into five groups (n = 6) viz. one DLA control and four Herb + DLA treated groups. All the four herb + DLA groups were pre-treated with respective herbs for 7 days and hematological indices were measured for entire five groups. On day-8 animals were inoculated with 1×106 DLA cells i.p., and Herb + DLA groups were continued with oral herbal treatment for 21-days. Hematological parameters and tumor volume were assessed to find the effects of herbs. Short term in vitro cytotoxicity was determined by Trypan Blue exclusion method and LDH leakage assay using different concentrations of herbal extracts and 5-FU as a positive control and IC50 for each herbal extract and 5-FU were determined. Oral administration of crude herb increased the survival time and decreased the peritoneal ascitic fluid content significantly. Hb, RBCs and total WBC which were altered by DLA inoculation were restored significantly by all the herbs except O. sanctum. All the four herbs showed in vitro cytotoxic activity against DLA cell-line. Moreover inter group comparison of all the four herbs for anti-tumor activity showed efficacy in the following order- T. cordifolia > Z. mauritiana ≥ C. longa > O. sanctum respectively. 相似文献
34.
35.
Sala F Mulet J Reddy KP Bernal JA Wikman P Valor LM Peters L König GM Criado M Sala S 《Neuroscience letters》2005,373(2):144-149
The effects of various Flustra foliacea metabolites on different types of human neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes were investigated. Whereas most of the compounds tested had a small blocking effect, one of them, deformylflustrabromine, selectively increased the current obtained in alpha4beta2 receptors when co-applied with acetylcholine (ACh). The current increase was reversible and concentration-dependent. This potentiating effect was still present at saturating concentrations of acetylcholine, and no changes in single-channel conductance or reversal potential were observed, thus suggesting a modification in the gating of alpha4beta2 receptors. Dwell time analysis of single channel records indicates that the mechanism of action of deformylflustrabromine could be both an increase of the opening rate constant and a decrease of the closing rate constant on alpha4beta2 receptors. Thus, deformylflustrabromine may constitute an excellent starting point for the future development of related agents able to potentiate human neuronal nicotinic receptor function. 相似文献
36.
Reddy BS Hirose Y Lubet RA Steele VE Kelloff GJ Rao CV 《International journal of molecular medicine》2000,5(4):327-330
Epidemiologic observations and laboratory research have suggested that dietary selenium reduces the risk of colon cancer. Selenium-enriched brewer's yeast as a dietary supplement reduces the incidence of and mortality from cancer of the colon in humans. It is not clear whether the observed inhibitory effect is due to selenomethionine, or to other forms of selenium, or to a mixture of the selenium compounds present in selenium-enriched brewer's yeast. Therefore, bioassay described in this study examined the chemopreventive efficacy of 10 and 15 ppm selenomethionine, equivalent to 3.6 and 5.4 ppm as selenium, against azoxymethane (AOM)-induced colon carcinogenesis. At five weeks of age, groups of male F344 rats were fed diets containing 0 (control diet), 10 or 15 ppm selenomethionine. At seven and eight weeks of age, all rats except those in vehicle-treated groups received s.c. injections of AOM at a dose rate of 15 mg/kg body wt. The rats were maintained on their respective diets for 52 weeks and were then sacrificed. Colon tumors were processed and evaluated histopathologically. Colon tumor incidence and multiplicity were analyzed statistically. No obvious toxic effects were observed following dietary administration of 10 or 15 ppm selenomethionine as indicated by body weight gain. Administration of 10 or 15 ppm selenomethionine had no significant effect on colon tumor incidence and multiplicity. This study suggests that i) selenomethionine lacks chemopreventive efficacy against AOM-induced colon carcinogenesis and ii) other forms of selenium or a mixture of selenium compounds present in selenium-enriched brewer's yeast need to be evaluated for their chemopreventive efficacy. 相似文献
37.
In this study, acute and chronic responses of pancreatic hepatocytes induced in F-344 rats by copper depletion-repletion protocol to certain hepatocarcinogens were examined. Administration of a single dose of tannic acid (subcutaneous), aflatoxin B1 (gavage), or lasiocarpine (intraperitoneally) caused characteristic nucleolar segregation in parenchymal cells of liver as well as in pancreatic hepatocytes. Chronic dietary administration of 2-acetylaminofluorene (0.025%) for 12 to 32 weeks led to the development of glutathione S-transferase-P-positive pancreatic hepatocytes in the pancreas. In addition, oval cell proliferation was observed in close association with pancreatic hepatocytes, but not in other areas of pancreas containing residual acinar cells. Oval cells in the pancreas and in the liver that developed in rats after chronic 2-acetylaminofluorene treatment and pancreatic duct cells stained positively with rat liver oval cell marker OV-6 antibodies by immunoperoxidase. These findings indicate that pancreatic hepatocytes respond to carcinogens in a fashion similar to parenchymal cells of liver. 相似文献
38.
Sordillo L. M. SooHoo H. Aherne K. M. Reddy C. C. Hogan J. S. 《Methods in Cell Science》1998,19(4):243-253
The purpose of this study was to develop culture conditions that would reduce glutathione peroxidase activity in bovine mammary endothelial cells. Conditions of reduce glutathione peroxidase activity were produced in vitro by culturing cells in selenium-deficient media. Low selenium levels were achieved by reducing serum concentrations; however, levels of essential growth factors also were reduced by this method. Therefore, cell proliferation was promoted by supplementation with combinations of defined serum components including insulin, transferrin, linoleic acid, bovine brain extract, and human epidermal growth factor. Out of seven different formulas tested, F12K medium containing 2% fetal bovine serum, insulin, transferrin, and linoleic acid was found to be conducive for cell proliferation. Upon confluence, endothelial cells cultured under these conditions consistently displayed short passage rates, consistent cell numbers, and classic cobblestone morphology when grown in the presence or absence of supplemental selenium. Additionally, these cells retained typical endothelial cell characteristics such as uptake of 1,1-dioctadecyl-3,3,3,3-tetramethylindo-carb ocyanine perchlorate acetylated low-density lipoprotein and the expression of cell adhesion molecules and von Willebrand Factor. 相似文献
39.
Illes Z Stern JN Keskin DB Reddy J Brosnan CF Waldner H Santambrogio L Kuchroo VK Strominger JL 《European journal of immunology》2005,35(12):3683-3693
The random amino acid copolymers FYAK and VWAK ameliorate EAE in a humanized mouse model expressing both a human transgenic myelin basic protein (MBP)85-99-specific T cell receptor and HLA-DR2. Here we show that microglia isolated from the central nervous system (CNS) of humanized mice with EAE induced by MBP85-99 and treated with these copolymers had reduced expression of HLA-DR, and thus reduced capacity to present MBP85-99 and activate transgenic T cells. In vitro microglia up-regulated empty HLA-DR2 upon activation with GM-CSF with or without LPS or IFN-gamma, but not with IL-4 or IL-10. Correspondingly, gene chip arrays showed that the CNS of untreated and YFAK-treated mice differentially expressed pro- and anti-inflammatory molecules during MBP85-99-induced EAE. Interestingly, microglia expressed the full-length gammabeta and alphabeta subunits of the tetrameric adaptor protein complexes AP-1 and AP-2 respectively, but after treatment with GM-CSF these complexes were cleaved, as had been found in immature dendritic cells derived from bone marrow. Strikingly, in vivo the perivascular lymphocyte infiltration seen in untreated mice immunized with MBP85-99 was composed of equal numbers of hVbeta2+ MPB85-99-specific transgenic and hVbeta2- endogenous T cells, while the much smaller infiltration seen after treatment with YFAK was composed predominantly of hVbeta2- endogenous T cells. 相似文献
40.
Pratt W Reddy MC McDonald DW Tarczy-Hornoch P Gennari JH 《Journal of biomedical informatics》2004,37(2):128-137
Many information systems have failed when deployed into complex health-care settings. We believe that one cause of these failures is the difficulty in systematically accounting for the collaborative and exception-filled nature of medical work. In this methodological review paper, we highlight research from the field of computer-supported cooperative work (CSCW) that could help biomedical informaticists recognize and design around the kinds of challenges that lead to unanticipated breakdowns and eventual abandonment of their systems. The field of CSCW studies how people collaborate with each other and the role that technology plays in this collaboration for a wide variety of organizational settings. Thus, biomedical informaticists could benefit from the lessons learned by CSCW researchers. In this paper, we provide a focused review of CSCW methods and ideas-we review aspects of the field that could be applied to improve the design and deployment of medical information systems. To make our discussion concrete, we use electronic medical record systems as an example medical information system, and present three specific principles from CSCW: accounting for incentive structures, understanding workflow, and incorporating awareness. 相似文献