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排序方式: 共有423条查询结果,搜索用时 12 毫秒
31.
32.
Ebron VH Yang Z Seyer DJ Kozlov ME Oh J Xie H Razal J Hall LJ Ferraris JP Macdiarmid AG Baughman RH 《Science (New York, N.Y.)》2006,311(5767):1580-1583
Artificial muscles and electric motors found in autonomous robots and prosthetic limbs are typically battery-powered, which severely restricts the duration of their performance and can necessitate long inactivity during battery recharge. To help solve these problems, we demonstrated two types of artificial muscles that convert the chemical energy of high-energy-density fuels to mechanical energy. The first type stores electrical charge and uses changes in stored charge for mechanical actuation. In contrast with electrically powered electrochemical muscles, only half of the actuator cycle is electrochemical. The second type of fuel-powered muscle provides a demonstrated actuator stroke and power density comparable to those of natural skeletal muscle and generated stresses that are over a hundred times higher. 相似文献
33.
S H Chae I H Jeong D H Choi J W Oh Y J Ahn 《Journal of agricultural and food chemistry》1999,47(3):934-938
The growth-inhibiting activity of Coptis japonica (Makino) root-derived materials toward eight human intestinal bacteria was examined using an impregnated paper disk method and compared to that of four commercially available isoquinoline alkaloids [berberine sulfate (BS), berberine iodide (BI), palmatine chloride (PC), and palmatine sulfate(PS)], as well as that of Thea sinensis leaf-derived epigallocatechin gallate (EGCG). The biologically active constituents of the Coptis extract were characterized as the isoquinoline alkaloids berberine chloride (BC), palmatine iodide (PI), and coptisine chloride (CC) by spectral analysis. The growth responses varied with both chemical and bacterial strain used. In a test using 500 microg/disk, BC and PI produced a clear inhibitory effect against Bifidobacterium longum, Bifidobacterium bifidum, Clostridium perfringens, and Clostridium paraputrificum, whereas weak or no inhibition was observed in Bifidobacterium adolescentis, Lactobacillus acidophilus, Lactobacillus casei, and Escherichia coli. At 1000 microg/ disk, CC revealed weak or no growth inhibition toward all test bacteria, whereas EGCG exhibited weak growth inhibition against only C. perfringens and C. paraputrificum. Among various isoquinoline alkaloids, BC exhibited more potent inhibitory activity toward C. perfringens than BI and BS, whereas the inhibitory effect was more pronounced in PI compared to PC and PS. The Coptis root-derived materials did not promote growth of B. longum and C. perfringens. 相似文献
34.
H. Yamazaki S. Takagi N. Oh Y. Hoshino K. Hosoya M. Okumura 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(1):204-210
Background
Definitive diagnosis of histiocytic sarcoma (HS) in dogs is relatively difficult by conventional histopathological examination because objective features of HS are not well defined.Hypothesis
Quantitative analysis of mRNA expression of selected cellular surface antigens (SAs) specific to HS in dogs can facilitate objective and rapid diagnosis.Animals
Dogs with HS (n = 30) and dogs without HS (n = 36), including those with other forms of lymphoma (n = 4), inflammatory diseases (n = 6), and other malignant neoplasias (n = 26).Methods
Retrospective clinical observational study. Specimens were collected by excisional biopsy, needle core biopsy, or fine needle aspiration. To determine HS detection efficacy, mRNA expression levels of selected SAs specific to HS in dogs, including MHC class IIα, CD11b, CD11c, and CD86, were quantitatively analyzed using real‐time quantitative polymerase chain reaction.Results
Each SA mRNA expression level was significantly higher in HS dogs than in non‐HS dogs (P = .0082). Cutoff values for discriminating between HS and non‐HS dogs based on these expression levels were calculated on the basis of receiver‐operating characteristic analysis. Accuracy of the cutoff values, including MHC class IIα, CD11b, CD11c, and CD86, was 87.9, 86.4, 86.4, and 84.8%, respectively.Conclusions and Clinical Importance
Our results suggest that quantitative analysis of mRNA expression of the selected SAs could be an adjunctive diagnostic technique with high diagnostic accuracy for HS in dogs. Substantial investigation is required for exclusion of diseases with similar cell types of origin to lymphoma. 相似文献35.
Kim CH Oh Y Han K Seo HW Kim D Park C Kang I Chae C 《Veterinary journal (London, England : 1997)》2012,192(1):120-122
Immunohistochemistry was used to demonstrate secreted mucins MUC2, MUC5AC and MUC5B and membrane-bound mucin MUC4 in the pulmonary bronchioles of piglets experimentally infected with Mycoplasma hyopneumoniae. Conventional status, Landrace-Duroc cross-bred piglets, 13 days of age, were randomised to two groups. One group (n=20) was infected by the intra-tracheal route with the SNU98703 strain of M. hyopneumoniae, and a group of 12 animals acted as uninfected controls. Five infected and three uninfected piglets were euthanased on the day of infection and at 7, 21, and 35 days post-inoculation (PI). Membrane-bound MUC4 and secreted MUC5AC were the predominant mucins produced in the bronchioles of the piglets in response to M. hyopneumoniae infection, but by day 35 PI, all labelled mucins had returned to pre-infection levels, contemporaneous with reduced pulmonary lesion scores. The increased mucin production may result from direct stimulation of the epithelium by mycoplasmal infection, or may arise indirectly following M. hyopneumoniae-induced ciliostasis. 相似文献
36.
Kim B Shin JH Han K Seo HW Oh Y Kang I Park C Lee BH Jang JS Kim SH Chae C 《Veterinary research communications》2011,35(7):469-475
The expression of myeloperoxidase (MPO) was examined in the swine influenza virus (SIV)-infected neutrophils in the lungs of pigs experimentally infected with swine influenza virus (SIV) subtype H1N2 by immunohistochemistry. Five pigs each from the infected and non-infected group were euthanized 1, 3, 5, 7, and 10?days post-inoculation (dpi). Immunohistochemical reactivity was mainly seen in neutrophils. The score for pulmonary histopathological lesions correlated with the score for MPO immunohistochemical reactivity (r ( s )?=?0.962, P?0.01). In addition, the score for in situ hybridization of SIV nucleic acid correlated with the score for MPO immunohistochemical reactivity (r ( s )?=?0.976, P?0.01). These results suggest neutrophils are one of the primary effector cells in the early phase of SIV infection in pigs. 相似文献
37.
Genetic characterization of canine rotavirus isolated from a puppy in Korea and experimental reproduction of disease. 总被引:3,自引:0,他引:3
38.
Comparative evaluation of MCP gene in worldwide strains of Megalocytivirus (Iridoviridae family) for early diagnostic marker 下载免费PDF全文
A Mishra G‐H Nam J‐A Gim H‐E Lee A Jo D Yoon S Oh S Kim A Kim D‐H Kim Y C Kim H D Jeong H‐J Cha Y H Choi H‐S Kim 《Journal of fish diseases》2018,41(1):105-116
Members of the Iridoviridae family have been considered as aetiological agents of iridovirus diseases, causing fish mortalities and economic losses all over the world. Virus identification based on candidate gene sequencing is faster, more accurate and more reliable than other traditional phenotype methodologies. Iridoviridae viruses are covered by a protein shell (capsid) encoded by the important candidate gene, major capsid protein (MCP). In this study, we investigated the potential of the MCP gene for use in the diagnosis and identification of infections caused Megalocytivirus of the Iridoviridae family. We selected data of 66 Iridoviridae family isolates (53 strains of Megalocytivirus, eight strains of iridoviruses and five strains of Ranavirus) infecting various species of fish distributed all over the world. A total of 53 strains of Megalocytivirus were used for designing the complete primer sets for identifying the most hypervariable region of the MCP gene. Further, our in silico analysis of 102 sequences of related and unrelated viruses reconfirms that primer sets could identify strains more specifically and offers a useful and fast alternative for routine clinical laboratory testing. Our findings suggest that phenotype observation along with diagnosis using universal primer sets can help detect infection or carriers at an early stage. 相似文献
39.
Zohreh Sankian Sanaz Khosravi Yi‐Oh Kim Sang‐Min Lee 《Journal of the World Aquaculture Society》2019,50(1):34-41
An 8‐week feeding trial was conducted to investigate the dietary protein requirement of juvenile mandarin fish, Siniperca scherzeri, a demersal freshwater piscivore with high commercial value in East Asia. Five isolipidic (100 g/kg) and isoenergetic (20 MJ/kg) practical diets were formulated to contain graded levels of 450, 500, 550, 600, and 650 g/kg crude protein, using mackerel fishmeal as the sole source of protein. Each of the five test diets was fed to visual satiety to triplicate groups of fish (initial mean body weight ± SE; 20.1 ± 0.2 g) reared in a recirculating freshwater system over the experimental period. Fish growth performance in terms of weight gain tended to improve with increasing dietary protein level, and the highest values were observed in those fish fed the 600–650 g/kg diets. Feed intake significantly declined as the protein content of the diet increased. Feed efficiency and protein retention tended to increase with increasing dietary protein levels, from 450 to 600 g/kg, and then declined when dietary protein content further increased to 650 g/kg. A similar trend was also found for the protein efficiency ratio, although the observed changes did not reach statistical significance. Whole‐body composition and plasma biochemical parameters were not significantly affected by the dietary protein content. Based on these findings and a broken‐line model of growth, 614.4 g/kg seems to be the proper amount of protein in a practical diet for >20 g mandarin fish. 相似文献
40.
Kyung-A Byun Seyeon Oh Myeongjoo Son Chul-Hyun Park Kuk Hui Son Kyunghee Byun 《Marine drugs》2021,19(9)
Increased inflammation is the main pathophysiology of nonalcoholic fatty liver disease (NAFLD). Inflammation affects lymphatic vessel function that contributes to the removal of immune cells or macromolecules. Dysfunctional lymphatic vessels with decreased permeability are present in NAFLD. High-fat diet (HFD) is known to increase body weight, food intake, and inflammation in the liver. Previously, it was reported that Ecklonia cava extracts (ECE) decreased food intake or weight gain, and low-calorie diet and weight loss is known as a treatment for NAFLD. In this study, the effects of ECE and dieckol (DK)—which is one component of ECE that decreases inflammation and increases lymphangiogenesis and lymphatic drainage by controlling lymphatic permeability in high-fat diet (HFD)-fed mice—on weight gain and food intake were investigated. ECE and DK decreased weight gain and food intake in the HFD-fed mice. NAFLD activities such as steatosis, lobular inflammation, and ballooning were increased by HFD and attenuated by ECE and DK. The expression of inflammatory cytokines such as IL-6 and TNF-α and infiltration of M1 macrophages were increased by HFD, and they were decreased by ECE or DK. The signaling pathways of lymphangiogenesis, VEGFR-3, PI3K/pAKT, and pERK were decreased by HFD, and they were restored by either ECE or DK. The expression of VE-cadherin (which represents lymphatic junctional function) was increased by HFD, although it was restored by either ECE or DK. In conclusion, ECE and DK attenuated NAFLD by decreasing weight gain and food intake, decreasing inflammation, and increasing lymphangiogenesis, as well as modulating lymphatic vessel permeability. 相似文献