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581.
582.
BACKGROUND: To describe the cytologic findings of a case of ganglioneuroblastoma metastatic to the jaw and neck. CASE: A 15-year-old boy with a known case of ganglioneuroblastoma of the kidney for the previous 10 years manifested by right mandibular and neck masses on 2 occasions 1 year apart was diagnosed with metastatic ganglioneuroblastoma by fine needle aspiration (FNA). FNA showed neurofibrillary material, small malignant cells, Homer-Wright rosettes. mononucleated, binucleated and multinucleated ganglion cells and Reed Sternberg-like ganglion cells. Metastatic ganglioneuroblastoma was diagnosed on both occasions, and the patient received appropriate treatment, with resolution of the lesions. CONCLUSION: This case illustrates the FNA findings of metastatic ganglioneuroblastoma in the head and neck region.  相似文献   
583.
Late Embryogenesis Abundant (LEA) proteins are associated with tolerance to water-related stress. A wheat (Triticum durum) group 2 LEA proteins, known also as dehydrin (DHN-5), has been previously shown to be induced by salt and abscisic acid (ABA). In this report, we analyze the effect of ectopic expression of Dhn-5 cDNA in Arabidopsis thaliana plants and their response to salt and osmotic stress. When compared to wild type plants, the Dhn-5 transgenic plants exhibited stronger growth under high concentrations of NaCl or under water deprivation, and showed a faster recovery from mannitol treatment. Leaf area and seed germination rate decreased much more in wild type than in transgenic plants subjected to salt stress. Moreover, the water potential was more negative in transgenic than in wild type plants. In addition, the transgenic plants have higher proline contents and lower water loss rate under water stress. Also, Na+ and K+ accumulate to higher contents in the leaves of the transgenic plants. Our data strongly support the hypothesis that Dhn-5, by its protective role, contributes to an improved tolerance to salt and drought stress through osmotic adjustment.  相似文献   
584.
Objective: The purpose of this study was to evaluate the effect of two post‐polymerisation treatments and different cycles of polymerisation on the cytotoxicity of two denture base resins. Materials and methods: The resins tested were Lucitone 550 and QC 20. Discs of resins were fabricated following the manufacturer's instructions. Lucitone 550 was processed by long cycle or short cycle. The resin QC 20 was processed by reverse cycle or normal cycle. The specimens were divided into groups: (i) post‐polymerised in microwave for 3 min at 500 W; (ii) post‐polymerised in water‐bath at 55°C for 60 min and (iii) without post‐polymerisation. Eluates were prepared by placing three discs into a sterile glass vial with 9 ml of Eagle's medium and incubated at 37°C for 24 hours. L929 cells were seeded into 96 well culture plates and DNA synthesis was assessed by 3H‐thymidine incorporation assay. Results: The results were submitted to two‐way anova and Tukey HSD test. QC 20 specimens polymerised by the normal cycle and submitted to microwave post‐polymerisation were graded as moderately cytotoxic. Similar results were observed for Lucitone 550 processed by long cycle without post‐polymerisation. The other experimental groups were graded as not cytotoxic. After water‐bath post‐polymerisation, specimens of Lucitone 550 processed by long cycle produced significantly lower inhibition of DNA synthesis than the other groups. Conclusion: The long cycle increased the cytotoxicity of Lucitone 550 and water‐bath post‐polymerisation reduced the cytotoxicity of Lucitone 550 processed by long cycle.  相似文献   
585.
Humanitarian demining requires to accurately detect, locate and deactivate every single landmine and other buried mine-like objects as safely and as quickly as possible, and in the most non-invasive manner. The quality of landmine detection affects directly the efficiency and safety of this process. Most of the available methods to detect explosives and landmines are limited by their sensitivity and/or operational complexities. All landmines leak with time small amounts of their explosives that can be found on surrounding ground and plant life. Hence, explosive signatures represent the robust primary indicator of landmines. Accordingly, developing innovative technologies and efficient techniques to identify in real-time explosives residue in mined areas represents an attractive and promising approach. Biological and biologically inspired detection technology has the potential to compete with or be used in conjunction with other artificial technology to complement performance strengths. Biological systems are sensitive to many different scents concurrently, a property that has proven difficult to replicate artificially. Understanding biological systems presents unique opportunities for developing new capabilities through direct use of trained bio-systems, integration of living and non-living components, or inspiring new design by mimicking biological capabilities. It is expected that controlled bio-systems, biotechnology and microbial techniques will contribute to the advancement of mine detection and other application domains. This paper provides directions, evaluation and analysis on the progress of controlled biological and biomimetic systems for landmine detection. It introduces and discusses different approaches developed, underlining their relative advantages and limitations, and highlighting trends, safety and ecology concern, and possible future directions.  相似文献   
586.
587.
Most human cells utilize glucose as the primary substrate, cellular uptake requiring insulin. Insulin signaling is therefore critical for these tissues. However, decrease in insulin sensitivity due to the disruption of various molecular pathways causes insulin resistance (IR). IR underpins many metabolic disorders such as type 2 diabetes and metabolic syndrome, impairments in insulin signaling disrupting entry of glucose into the adipocytes, and skeletal muscle cells. Although the exact underlying cause of IR has not been fully elucidated, a number of major mechanisms, including oxidative stress, inflammation, insulin receptor mutations, endoplasmic reticulum stress, and mitochondrial dysfunction have been suggested. In this review, we consider the role these cellular mechanisms play in the development of IR.  相似文献   
588.
The present study aimed to evaluate the potential therapeutic effect of pantoprazole, a proton-pump inhibitor, on precancerous lesion (PCL) in rats. diethylnitrosamine and 2-acetylaminofluorene were used to induce PCL in rats, in vivo. The rats were treated with three doses of pantoprazole (100, 50, and 25  mg/kg; three times weekly) during the last 4 weeks of the total 10 weeks of the experiment. Blood and liver tissue samples were collected for measurement of the exosomal abundance and exosomal competing endogenous RNA markers. Results revealed that pantoprazole administration had an ameliorating effect on liver function tests and microscopic features of the liver; and decreased exosome abundance in the liver tissue samples and sera of the rats. Meanwhile, the treatment also resulted in a dose-dependent decrease in exosomal RAB11A mRNA and long noncoding RNA RP11-513I15.6, which is an important participant in th exosomal secretion process with an increase in exosomal miRNA-1262. Based on these results, we postulated that pantoprazole has the potential to attenuate liver tumorigenesis in this rat model.  相似文献   
589.
INTRODUCTIONRecombinant DNA technology is a powerful toolfor the introduction of foreign genes into longlivedperennials and fOr fundamelltal studies of gene expression. Using such techniques, we can overcomethe difficulties associated with the breeding of a long-lived perennial. At present, although considerablereseaxch effort has been devoted to the genetic en-gineering of fOrest trees, it has lagged behind ad-vances made in herbaceous crops due both to eco-nomics and the recalcitrant n…  相似文献   
590.
Recent integrative systematic studies of Vitaceae support the recognition of a new genus Pseudocayratia J.Wen, L.M.Lu & Z.D.Chen. The genus consists of five species from China and Japan. We herein describe the following two new species: Pseudocayratia speciosa J.Wen & L.M.Lu, and P. pengiana Hsu & J.Wen, and make three new combinations: Pseudocayratia dichromocarpa (H.Lév.) J.Wen & Z.D.Chen, P. oligocarpa (H.Lév. & Van.) J.Wen & L.M.Lu, and P. yoshimurae (Makino) J.Wen & V.C.Dang. Phylogenetic analyses based on five chloroplast loci strongly support Pseudocayratia as sister to Tetrastigma. Morphologically, species of the genus have stigmas enlarged (but not 4‐lobed), pedicels at fruiting stage enlarged and fleshy, seeds with a crustaceous thin testa, circular cup‐like ventral infolds, linear chalaza extending ca. 2/3 to 3/4 of the seed length (from apex to base), lateral margin with thin edges, and T‐shaped endosperm in cross‐section. The genus is distributed in eastern Asia (China and Japan). The taxonomic novelties we report in this study at both the generic and species levels highlight the importance of collections‐based research in today's integrative systematics.  相似文献   
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