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排序方式: 共有662条查询结果,搜索用时 15 毫秒
1.
Ji Hye Yang Sae Kwang Ku IL Je Cho Je Hyeon Lee Chang-Su Na Sung Hwan Ki 《International journal of molecular sciences》2021,22(4)
Hepatic fibrosis occurs when liver tissue becomes scarred from repetitive liver injury and inflammatory responses; it can progress to cirrhosis and eventually to hepatocellular carcinoma. Previously, we reported that neoagarooligosaccharides (NAOs), produced by the hydrolysis of agar by β-agarases, have hepatoprotective effects against acetaminophen overdose-induced acute liver injury. However, the effect of NAOs on chronic liver injury, including hepatic fibrosis, has not yet been elucidated. Therefore, we examined whether NAOs protect against fibrogenesis in vitro and in vivo. NAOs ameliorated PAI-1, α-SMA, CTGF and fibronectin protein expression and decreased mRNA levels of fibrogenic genes in TGF-β-treated LX-2 cells. Furthermore, downstream of TGF-β, the Smad signaling pathway was inhibited by NAOs in LX-2 cells. Treatment with NAOs diminished the severity of hepatic injury, as evidenced by reduction in serum alanine aminotransferase and aspartate aminotransferase levels, in carbon tetrachloride (CCl4)-induced liver fibrosis mouse models. Moreover, NAOs markedly blocked histopathological changes and collagen accumulation, as shown by H&E and Sirius red staining, respectively. Finally, NAOs antagonized the CCl4-induced upregulation of the protein and mRNA levels of fibrogenic genes in the liver. In conclusion, our findings suggest that NAOs may be a promising candidate for the prevention and treatment of chronic liver injury via inhibition of the TGF-β/Smad signaling pathway. 相似文献
2.
Manku T. McGregor J.M. Nathan A. Roulston D.J. Noel J.-P. Houghton D.C. 《Electron Devices, IEEE Transactions on》1993,40(11):1990-1996
Results of the drift hole mobility in strained and unstrained SiGe alloys are reported for Ge fractions varying from 0 to 30% and doping levels of 1015-1019 cm-3. The mobilities are calculated taking into account acoustic, optical, alloy, and ionized-impurity scattering. The mobilities are then compared with experimental results for a boron doping concentration of 2×1019 cm-3. Good agreement between experimental and theoretical values is obtained. The results show an increase in the mobility relative to that of silicon 相似文献
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Carolyn McGregor Bruce Kneale Mark Tracy 《Journal of Network and Computer Applications》2007,30(4):1309-1323
Premature and ill term babies born in regional Australia must be moved to another hospital with Neonatal Intensive Care Unit (NICU) facilities. Transferred pre-term and critically ill term babies have higher mortality rates and much higher rates of long term disability than similar babies born in hospitals with NICU facilities. This paper details the Bush Babies Broadband project that aims to significantly improve the quality of treatment for babies born in rural, remote as well as urban areas by providing the first on-demand virtual NICU architecture in Australia. Real-time data collected from medical monitors and ventilators attached to the baby, audiovisual streams and static physiological data such as X-ray images are transmitted to the consulting Neonatologist to gain a better picture of the patient's condition than is currently available. The key contribution of this significant research is the infrastructure providing a mechanism for Neonatologists to receive information directly from a regional hospital, thereby preventing, in some cases, the immediate need to move the baby. A key benefit of this framework is that it is available to link regional hospitals with the supporting NICU Neonatologist ‘on demand’ eliminating the need to establish permanent point to point connections. This paper further describes the application of that architecture to a specific pilot connecting the Bathurst regional hospital with Neonatologists within the NICU at Nepean Hospital, Penrith Australia. 相似文献
8.
The first magnetic resonance imaging profiles of chloride content in low- and high-permeability Portland cement mortar have been obtained using a novel material science imaging technique. The penetration of water as well as chloride and sodium ions, into mortar specimens was monitored for a period of 72 h. Marked differences in penetration depth were observed in low- and high-permeability mortar. These preliminary experiments show significant differences between the extent and nature in the penetration of chlorides compared to water and sodium. 相似文献
9.
MJ Prado AL Nicastri PL Costa T Rockman IL Tersariol HB Nader RT Barros EB Prado 《Canadian Metallurgical Quarterly》1997,30(7):865-872
The aim of the present study was to evaluate renal and liver distribution of two monoclonal immunoglobulin light chains. The chains were purified individually from the urine of patients with multiple myeloma and characterized as lambda light chains with a molecular mass of 28 kDa. They were named BJg (high amount of galactose residues exposed) and BJs (sialic acid residues exposed) on the basis of carbohydrate content. A scintigraphic study was performed on male Wistar rats weighing 250 g for 60 min after i.v. administration of 1 mg of each protein (7.4 MBq), as the intact proteins and also after carbohydrate oxidation. Images were obtained with a Siemens gamma camera with a high-resolution collimator and processed with a MicroDelta system. Hepatic and renal distribution were established and are reported as percent of injected dose. Liver uptake of BJg was significantly higher than liver uptake of BJs (94.3 vs 81.4%) (P < 0.05). This contributed to its greater removal from the intravascular compartment, and consequently lower kidney accumulation of BJg in comparison to BJs (5.7 vs 18.6%) (P < 0.05). After carbohydrate oxidation, there was a decrease in hepatic accumulation of both proteins and consequently a higher renal overload. The tissue distribution of periodate-treated BJg was similar to that of native BJs: 82.7 vs 81.4% in the liver and 17.3 vs 18.6% in the kidneys. These observations indicate the important role of sugar residues of Bence Jones proteins for their recognition by specific membrane receptors, which leads to differential tissue accumulation and possible toxicity. 相似文献
10.
S Sawaguchi BY Yue JE Kawa IL Chang SS Twining B Meberg 《Canadian Metallurgical Quarterly》1994,35(1):251-261
PURPOSE: To examine in the human trabecular meshwork lysosomal enzymes and one inhibitor of serine proteases that actively participate in the degradation of macromolecules into low molecular weight constituents. METHODS: Using an avidin-biotin-peroxidase technique, lysosomal proteases and alpha 1-proteinase inhibitor were examined in the trabecular meshwork of 23 human eyes with donor ages ranging from 2 to 90 years. These eyes were categorized into three age groups (< or = 20, 21 to 49, and > or = 50 years). Histochemical staining for lysosomal hydrolases was also performed on frozen sections of 20 human eyes. The staining was analyzed by an image analyzer and the levels of lysosomal proteases were further measured by biochemical assays. RESULTS: The trabecular meshwork from all the eyes stained intensely against antibodies to cathepsins B and G and alpha 1-proteinase inhibitor. The staining for elastase was weaker but evident. Image analyses revealed that the staining intensity for each protease or inhibitor was similar in all age groups. The staining in the uveal meshwork appeared to be the strongest among all the trabecular meshwork regions. Biochemical assays of tissue extracts confirmed that the enzyme and inhibitor levels were comparable among the three donor age groups. Activities of two lysosomal hydrolases, acid phosphatase and acid esterase, were also found in trabecular meshwork cells of 20 eyes. No apparent difference in enzyme activities was found with increasing age, and variation related to region was not observed. CONCLUSIONS: This study demonstrated the age-independent distribution of a variety of lysosomal enzymes and a protease inhibitor in the human trabecular meshwork. The presence of these proteins suggests a possible role in the metabolic operation of the trabecular meshwork. 相似文献