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101.
The value of fine catheter aspiration cytology in the diagnosis of metastatic tumours is illustrated by a case of pleomorphic giant cell carcinoma of the pancreas which had metastasized to the peritoneal cavity. The finding of unequivocal malignant cells obviated the need for further diagnostic procedures. Electron microscopy and immunostaining further substantiated the light microscopic cytodiagnosis and identified the tumour type and source of the primary tumour. Furthermore, subsequent cell block preparation from the aspirated material demonstrated the histological features of this tumour.  相似文献   
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Hyperglycemia- and oxidative stress-induced modification of circulating lipoproteins is being increasingly recognized as an important pathogenetic factor for diabetic cardiovascular damages. This study was designed to investigate the impact of modified very low-density lipoprotein and high-density lipoprotein on phagocyte adhesion to endothelial cells and the involvement of scavenger receptor class B type 1 (SR-BI) in this process. Native lipoproteins were isolated by density gradient ultracentrifugation and in vitro glycoxidative or oxidative modification was performed in the presence of glucose or sodium hypochlorite, respectively. One hour co-incubation experiments with lipoproteins, freshly prepared polymorphonuclear leukocytes (PMN), and venous endothelial cells (HUVEC) were performed in the presence or absence of different scavenger receptors and signal transduction inhibitors. PMN adhesion to HUVEC was quantified fluorimetrically. We demonstrated that oxidized and glycoxidized lipoproteins promote adhesion of PMN to HUVEC from 1.5- to 2.5-fold with oxidized lipoproteins having the greatest effect. Treatment with the highly specific SR-BI inhibitor, BLT-1 produced substantial reduction of lipoprotein-induced adhesion to endothelial cells. Native and modified lipoproteins recruited extracellular signal-regulated kinase (ERK 1/2), p38 mitogen-activated protein kinase, and Janus kinase 2 as downstream signaling pathways for adhesion. From this study, it could be concluded that modification of lipoproteins plays a crucial role in atherosclerotic progression and SR-BI may be considered as a potential therapeutic target for the prevention of diabetic cardiovascular complications.  相似文献   
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Primers for five polymorphic microsatellite loci were developed for the midget faded rattlesnake (Crotalus viridis concolor), a rare subspecies of western rattlesnake (Crotalus viridus) found only in parts of Wyoming, Colorado, and Utah. Five polymorphic microsatellites were isolated, four of which had relatively high levels of diversity (eight to nine alleles). We found only two departures from Hardy–Weinberg equilibrium and they occurred in different loci, so null alleles are likely not a problem. Moreover, we found that no two loci were linked. These loci will be applicable for population genetic analysis and perhaps analysis of paternity and mating systems.  相似文献   
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Neurochemical Research - Depression is an emotional disorder that causes mental and physical changes, and has limited pharmacotherapy. Tannic acid (TA) is a polyphenol with previously described...  相似文献   
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The Biginelli reaction is a multicomponent reaction involving the condensation between an aldehyde, a β-ketoester, and urea or thiourea, in the presence of an acid catalyst, producing dihydropyrimidinones (DHPMs). Owing to their important pharmacological properties, the DHPMs have been studied by many authors. However, most of the methodologies used for the synthesis of these compounds require drastic reaction conditions. In the current study, we report an efficient and clean procedure for preparing DHPMs by the use of citric acid or tartaric acid as a promoter of the Biginelli synthesis in ethanol as solvent. In addition, we have evaluated the antioxidant capacity of the compounds synthesized by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and the thiobarbituric acid-reactive species test. Two compounds presented antioxidant activity and also reduced lipid peroxidation at concentrations of 200 and 300 μM. In summary, we report an environmentally friendly procedure for the preparation of DHPMs and demonstrate the antioxidant capacity of some of the compounds.  相似文献   
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ABSTRACT. Total DNA/organism was determined by flow cytometry on stocks of 33 single-cell-isolate clones and one strain of mithramycin-stained Trypanosoma cruzi. Interstrain differences in mean total DNA/group of 34% and interclone differences in total DNA/organism of 41% were found. Microspectrofluorometric analyses of the trypomastigote stage of selected clones confirmed the flow cytometry data and indicated that the total DNA/organism differences were due to differences in DNA of both the nucleus and kinetoplast with the nucleus being the major contributing factor. These data imply that the potential for genetic diversity in T. cruzi may be very large.  相似文献   
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