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61.
Mihyun Choi Namsoon Lee Ahyoung Kim Seoyeon Keh Jinsoo Lee Hyunwook Kim Mincheol Choi 《Veterinary radiology & ultrasound》2014,55(1):102-108
Diagnosis of unilateral diaphragmatic paralysis in dogs is currently based on fluoroscopic detection of unequal movement between the crura. Bilateral paralysis may be more difficult to confirm with fluoroscopy because diaphragmatic movement is sometimes produced by compensatory abdominal muscle contractions. The purpose of this study was to develop a new method to evaluate diaphragmatic movement using M‐mode ultrasonography and to describe findings for normal and diaphragmatic paralyzed dogs. Fifty‐five clinically normal dogs and two dogs with diaphragmatic paralysis were recruited. Thoracic radiographs were acquired for all dogs and fluoroscopy studies were also acquired for clinically affected dogs. Two observers independently measured diaphragmatic direction of motion and amplitude of excursion using M‐mode ultrasonography for dogs meeting study inclusion criteria. Eight of the clinically normal dogs were excluded due to abnormal thoracic radiographic findings. For the remaining normal dogs, the lower limit values of diaphragmatic excursion were 2.85–2.98 mm during normal breathing. One dog with bilateral diaphragmatic paralysis showed paradoxical movement of both crura at the end of inspiration. One dog with unilateral diaphragmatic paralysis had diaphragmatic excursion values of 2.00 ± 0.42 mm on the left side and 4.05 ± 1.48 mm on the right side. The difference between left and right diaphragmatic excursion values was 55%. Findings indicated that M‐mode ultrasonography is a relatively simple and objective method for measuring diaphragmatic movement in dogs. Future studies are needed in a larger number of dogs with diaphragmatic paralysis to determine the diagnostic sensitivity of this promising new technique. 相似文献
62.
The establishment of pregnancy is a complex process that requires a well-coordinated interaction between the implanting conceptus and the maternal uterus. In pigs, the conceptus undergoes dramatic morphological and functional changes at the time of implantation and introduces various factors, including estrogens and cytokines,interleukin-1β2(IL1 B2), interferon-γ(IFNG), and IFN-δ(IFND), into the uterine lumen. In response to ovarian steroid hormones and conceptus-derived factors, the uterine endometrium becomes receptive to the implanting conceptus by changing its expression of cell adhesion molecules, secretory activity, and immune response. Conceptus-derived estrogens act as a signal for maternal recognition of pregnancy by changing the direction of prostaglandin(PG) F2αfrom the uterine vasculature to the uterine lumen. Estrogens also induce the expression of many endometrial genes,including genes related to growth factors, the synthesis and transport of PGs, and immunity. IL1 B2, a pro-inflammatory cytokine, is produced by the elongating conceptus. The direct effect of IL1 B2 on endometrial function is not fully understood. IL1 B activates the expression of endometrial genes, including the genes involved in IL1 B signaling and PG synthesis and transport. In addition, estrogen or IL1 B stimulates endometrial expression of IFN signaling molecules,suggesting that estrogen and IL1 B act cooperatively in priming the endometrial function of conceptus-produced IFNG and IFND that, in turn, modulate endometrial immune response during early pregnancy. This review addresses information about maternal-conceptus interactions with respect to endometrial gene expression in response to conceptus-derived factors, focusing on the roles of estrogen and IL1 B during early pregnancy in pigs. 相似文献
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64.
Joohyun Jung DVM MS Mincheol Choi DVM PHD Jinhwa Chang DVM Sungjoon Won DVM Woqjo Chung DVM Hojung Choi DVM MS Kichang Lee DVM MS Junghee Yoon DVM PHD Hyunkwon Ha MD PHD 《Veterinary radiology & ultrasound》2003,44(6):642-645
This study was performed to evaluate and optimize a small bowel contrast technique using barium and methylcellulose in dogs. Ten healthy dogs underwent both a conventional upper gastrointestinal study that used only barium and a modified study that used barium and methylcellulose. The control group received 10 mL/kg of 40% barium suspension. Experimental groups were divided into three subgroups given 15 mL/kg of different viscosities (low, moderate, and high viscosity) of 0.5% methylcellulose after 4 mL/kg of 40% barium suspension. Compared with the control group, dogs receiving methylcellulose had higher-quality upper gastrointestinal studies. Moderate viscosity of methylcellulose was superior to the other methylcellulose groups. In conclusion, the use of methylcellulose is a simple and effective method for improving the image quality in an upper GI examination. 相似文献
65.
Owing to unique structure and characteristics of carbon nanotubes, much more are attracted attentions since they were discovered. In recent years, carbon nanotubes have been successfully synthesized by various methods. Especially, highly aligned carbon nanotubes were grown by chemical vapor deposition (CVD) and the oriented growth of carbon nanotubes became realized, resulting in many applications of carbon nanotubes and researches on them. In the work, the methods and mechanisms of orientation growth of carbon nanotubes were reviewed, and it was analyzed and discussed that different methods influenced on the process of growing carbon nanotubes. Simultaneously, it was emphatically analyzed that catalyst particles affected on orientation growth of carbon nanotubes during their growth. 相似文献
66.
Anti-inflammatory inhibition of endothelial cell adhesion molecule expression by flavone derivatives
Kwon HM Choi YJ Jeong YJ Kang SW Kang IJ Lim SS Kang YH 《Journal of agricultural and food chemistry》2005,53(13):5150-5157
Endothelial expression of cell adhesion molecules (CAM) including VCAM-1, E-selectin, and PECAM-1 plays a leading role in atherosclerosis. Phenolic flavones have been shown to have an anti-inflammatory property. This study examines whether 3',4'-dimethoxy-7-hydroxyflavone (methoxyflavone) and 2',3',7-trihydroxyflavone (hydroxyflavone) inhibited monocyte adhesion to TNF-alpha-activated endothelium via reduction of CAM expression in human umbilical vein endothelial cells (HUVEC). In stimulated HUVEC the expression of VCAM-1 and E-selectin was enhanced with increasing mRNA levels. Methoxyflavone markedly interfered with the THP-1 monocyte adhesion to TNF-alpha-stimulated HUVEC. At concentrations of > or =25 microM, methoxyflavone blocked the induction of VCAM-1 but not that of E-selectin on the activated HUVEC. Immunocytochemical staining showed that methoxyflavone modestly inhibited PECAM-1 expression induced by TNF-alpha. In contrast, hydroxyflavone minimally inhibited TNF-alpha-stimulated E-selectin expression without affecting VCAM-1 level. The inhibitory effect of methoxyflavone on THP-1 adhesion to HUVEC appears to be greater than that of hydroxyflavone, most likely due to a greater inhibition of CAM expression. Thus, some flavone derivatives containing methoxy groups may have therapeutic potential attenuating inflammatory response-related atherosclerosis. 相似文献
67.
Ji-Hoon Kim Won Sik Shin Dong-Ik Song Sang June Choi 《Water, air, and soil pollution》2005,166(1-4):367-380
Single- and bi-solute sorption and desorption of 2,4-dichlorophenol (2,4-DCP) and 2,4,5-trichlorophenol (2,4,5-TCP) in montmorillonite modified with hexadecyltrimethylammonium (HDTMA) were investigated using multi-step sorption and desorption procedure. Effect of pH on the multi-step sorption and desorption was investigated. As expected by the magnitude of octanol-water partition coefficient, K ow , both sorption and desorption affinity of 2,4,5-TCP was higher than that of 2,4-DCP at pH 4.85 and 9.15. For both chlorophenols, the protonated speciation (at pH 4.85) exhibited a higher affinity in both sorption and desorption than the predominant deprotonated speciation (about 95% and 99% of 2,4-dichlorophenolate and 2,4,5-trichlophenolate anions at pH 9.15, respectively). Desorption of chlorinated phenols was strongly dependent on the current pH regardless of their speciation in the previous sorption stage. Freundlich model was used to analyze the single-solute sorption and desorption data. No appreciable desorption-resistant (or non-desorbing) fraction was observed in organoclays after several multi-step desorptions. This indicates that sorption of phenols in organoclay mainly occurs via partitioning into the core of the pseudo-organic medium, thereby causing desorption nearly reversible. In bisolute competitive systems, sorption (or desorption) affinity of both chlorophenols was reduced compared to that in its single-solute system due to the competition between the solutes. The ideal adsorbed solution theory (IAST) coupled to the single-solute Freundlich model successfully predicted bisolute multi-step competitive sorption and desorption equilibria. 相似文献
68.
Chung HY Choi HR Park HJ Choi JS Choi WC 《Journal of agricultural and food chemistry》2001,49(8):3614-3621
Peroxynitrite (ONOO(-)), formed from the reaction of superoxide (O(2)*(-)) and nitric oxide (*NO), is a cytotoxic species that can oxidize several cellular components such as proteins, lipids, and DNA. It has been implicated in diseases such as Alzheimer's disease, rheumatoid arthritis, cancer, and atherosclerosis. Due to the lack of endogenous enzymes responsible for ONOO(-) inactivation, developing a specific ONOO(-) scavenger is of considerable importance. The aim of this study was to evaluate the ability of marine natural products to scavenge ONOO(-) and to protect cells against ONOO(-). Methanolic extracts of 17 marine alga were tested for their ONOO(-) scavenging activity. Among them, Symphyocladia latiuscula showed the potent scavenging activity. CH(2)CH(2) fraction was partitioned with CH(2)CH(2) following n-hexanal extraction from the methanol extract of S. latiuscula. It was highly effective for ONOO(-) scavenging activity. Further analysis of the active fractionated extract identified 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (TDB) as a potent ONOO(-) scavenger. The data demonstrated that TDB led to decreased ONOO(-)-mediated nitration of tyrosine through electron donation. TDB showed significant inhibition on nitration of bovine serum albumin and low-density lipoprotein by ONOO(-) in a dose-dependent manner. It also provided cytoprotection from cell damage induced by ONOO(-). TDB can be developed as an effective peroxynitrite scavenger for the prevention of the involved diseases. 相似文献
69.
70.
Two lymphocytoid cell lines have been established from a patient with the Lesch-Nyhan syndrome. The cells are deficient in hypoxanthine-guanine phosphoribosyltransferase, as demonstrated by their failure to incorporate [H(3)]hypoxanthine and by their inability to grow in medium in which they were nutritionally dependent upon exogenous hypoxanthine. This represents the first establishment of presumptively permanent human lymphocytoid cell lines that are deficient in a specific enzyme. 相似文献