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排序方式: 共有193条查询结果,搜索用时 218 毫秒
1.
STRAIN ELASTOGRAPHY USING DOBUTAMINE‐INDUCED CAROTID ARTERY PULSATION IN CANINE THYROID GLAND 下载免费PDF全文
Gahyun Lee Sunghoon Jeon Sang‐Kwon Lee Hyunwoo Kim Dohyeon Yu Jihye Choi 《Veterinary radiology & ultrasound》2015,56(5):549-553
Thyroid disease is common in dogs and conventional ultrasonography is a standard diagnostic test for diagnosis and treatment planning. Strain elastography can provide additional information about tissue stiffness noninvasively after applying external or internal compression. However, natural carotid artery pulsations in the canine thyroid gland are too weak to maintain sufficient internal compression force. The objective of the present study was to describe the feasibility of strain elastography for evaluating the canine thyroid gland and the repeatability of dobutamine‐induced carotid artery pulsation as an internal compression method. In seven healthy Beagle dogs, strain on each thyroid lobe was induced by external compression using the ultrasound probe and internal compression using carotid artery pulsation after dobutamine infusion. The thyroid appeared homogeneously green and the subcutaneous fat superficial to the thyroid lobe appeared blue. Strain values and strain ratios did not differ among dogs or between the left and right lobes. Interobserver repeatability was excellent for both compression methods. Intraobserver repeatability of the strain ratio measured using the carotid artery pulsation method (intraclass coefficient correlation = 0.933) was higher than that measured using the external compression method (0.760). Mean strain values of thyroid lobes for the external compression method (142.93 ± 6.67) differed from the internal method (147.31 ± 8.24; P < 0.05). Strain ratios between the two methods did not differ. Strain elastography was feasible for estimating thyroid stiffness in dogs. Carotid artery pulsation induced by dobutamine infusion can be used for canine thyroid strain elastography with excellent repeatability. 相似文献
2.
Jong-Hyun Moon Hae-Won Jung Hee-Chun Lee Joon-Hyeok Jeon Na-Hyun Kim Jung-Hyang Sur Jeongim Ha Dong-In Jung 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(2):203-211
In the present study, the use of dogs with experimental autoimmune encephalomyelitis (EAE) as a disease model for necrotizing encephalitis (NE) was assessed. Twelve healthy dogs were included in this study. Canine forebrain tissues (8 g), including white and grey matter, were homogenized with 4 mL of phosphate-buffered saline for 5 min in an ice bath. The suspension was emulsified with the same volume of Freund''s complete adjuvant containing 1 mg/mL of killed Mycobacterium tuberculosis H37Ra. Under sedation, each dog was injected subcutaneously with canine brain homogenate at four sites: two in the inguinal and two in the axillary regions. A second injection (booster) was administered to all the dogs using the same procedure 7 days after the first injection. Clinical assessment, magnetic resonance imaging, cerebrospinal fluid analyses, necropsies, and histopathological and immunohistochemical examinations were performed for the dogs with EAE. Out of the 12 animals, seven (58%) developed clinically manifest EAE at various times after immunization. Characteristics of canine EAE models were very similar to canine NE, suggesting that canine EAE can be a disease model for NE in dogs. 相似文献
3.
Geun Hye Hwang Yu Jin Jeon Ho Jae Han Soo Hyun Park Kyoung Min Baek Woochul Chang Joong Sun Kim Lark Kyun Kim You-Mie Lee Sangkyu Lee Jong-Sup Bae Jun-Goo Jee Min Young Lee 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(1):17-23
Butylated hydroxyanisole (BHA) is a synthetic phenolic compound consisting of a mixture of two isomeric organic compounds: 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. We examined the effect of BHA against hydrogen peroxide (H2O2)-induced apoptosis in primary cultured mouse hepatocytes. Cell viability was significantly decreased by H2O2 in a dose-dependent manner. Additionally, H2O2 treatment increased Bax, decreased Bcl-2, and promoted PARP-1 cleavage in a dose-dependent manner. Pretreatment with BHA before exposure to H2O2 significantly attenuated the H2O2-induced decrease of cell viability. H2O2 exposure resulted in an increase of intracellular reactive oxygen species (ROS) generation that was significantly inhibited by pretreatment with BHA or N-acetyl-cysteine (NAC, an ROS scavenger). H2O2-induced decrease of cell viability was also attenuated by pretreatment with BHA and NAC. Furthermore, H2O2-induced increase of Bax, decrease of Bcl-2, and PARP-1 cleavage was also inhibited by BHA. Taken together, results of this investigation demonstrated that BHA protects primary cultured mouse hepatocytes against H2O2-induced apoptosis by inhibiting ROS generation. 相似文献
4.
Eui Jeong Han Hyun-Soo Kim Kalu Kapuge Asanka Sanjeewa Kyungsook Jung Youngheun Jee You-Jin Jeon Ilekuttige Priyan Shanura Fernando Ginnae Ahn 《Marine drugs》2020,18(12)
Sargassum horneri (S. horneri), an edible brown alga, has been proposed as a functional food with an improvement effect on abnormal skin immune responses. The present study investigates the anti-allergic effect of an ethanol extract from S. horneri (SHE) on immunoglobulin E (IgE)/bovine serum albumin (BSA)-mediated activation in bone marrow-derived cultured-mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) reaction in mice. SHE markedly and dose-dependently suppressed the degranulation of BMCMCs by reducing the β-hexosaminidase and histamine release without cytotoxicity. In addition, SHE significantly decreased the FcεRI expression on the surface of BMCMCs and its IgE binding. Moreover, SHE reduced the mRNA expression and the production of allergic cytokines; interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-10, IL-13; interferon (IFN)-γ and/or tumor necrosis factor (TNF)-α; and a chemokine, thymus and activation-regulated chemokine (TARC), by suppressing the activation of Src-family kinases and nuclear factor (NF)-κB signaling. In further study, the application of SHE reduced the PCA reaction in an IgE/BSA-induced type I allergic mice model. Taken together, we suggest that SHE has an anti-allergic effect in type I allergic responses. 相似文献
5.
Rheum undulatum root has been used traditionally in Korea for the treatment of dental diseases. The purpose of this study was to separate a fraction from R. undulatum showing anti-acid production activity against Streptococcus mutans biofilms and identify the main components in that fraction. Methanol extract of R. undulatum root and its fractions were prepared. To select a fraction exhibiting anti-acid production activity, suspension glycolytic pH-drop assay was performed. Among the fractions tested, dichloromethane fraction exhibited the strongest activity in a dose-dependent manner. To examine the effect of the selected fraction on the anti-acid production of S. mutans biofilms, 74 h old S. mutans biofilms were used. The selected fraction reduced the initial rate of acid production of S. mutans biofilms at sub-minimum inhibitory concentration (MIC) levels. HPLC qualitative analysis of the selected fraction indicated that the presence of anthraquinone derivatives, such as aloe-emodin, emodin, chrysophanol and physcion, as main components. 相似文献
6.
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)- 1,2-isoxazoline as a useful rice herbicide 总被引:1,自引:0,他引:1
Hwang IT Kim HR Jeon DJ Hong KS Song JH Cho KY 《Journal of agricultural and food chemistry》2005,53(22):8639-8643
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline derivative was synthesized, and its herbicidal activity was assessed under glasshouse and flooded paddy conditions. 5-(2,6-Difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 125 g of a.i. ha(-1) under greenhouse conditions. Soil application of this compound showed complete control of barnyard-grass to the fourth leaf stage at 250 g of a.i. ha(-1). Field trials indicated that this compound controlled annual weeds rapidly with a good tolerance on transplanted rice seedlings by post-emergence and soil application. This compound showed a low mammalian and environmental toxicity in various toxicological tests. 相似文献
7.
Chitosan as an edible invisible film for quality preservation of herring and atlantic cod 总被引:5,自引:0,他引:5
The effect of chitosan with different molecular weights as coatings for shelf-life extension of fresh fillets of Atlantic cod (Gadus morhua) and herring (Clupea harengus) was evaluated over a 12-day storage at refrigerated temperature (4 +/- 1 degrees C). Three chitosan preparations from snow crab (Chinoecetes opilio) processing wastes, differing in viscosities and molecular weights, were prepared; their apparent viscosities (360, 57, and 14 cP) depended on the deacetylation time (4, 10, and 20 h, respectively) of the chitin precursor. Upon coating with chitosans, a significant (p < or = 0.05) reduction in relative moisture losses of 37, 29, 29, 40, and 32% was observed for cod samples coated with 360 cP chitosan after 4, 6, 8, 10, and 12 days of storage, respectively. Chitosan coating significantly (p < or = 0.05) reduced lipid oxidation as displayed in peroxide value, conjugated dienes, 2-thiobarbituric acid reactive substances and headspace volatiles, chemical spoilage as reflected in total volatile basic nitrogen, trimethylamine, and hypoxanthine, and growth of microorganisms as reflected in total plate count in both fish model systems compared to uncoated samples. The preservative efficacy and the viscosity of chitosan were inter-related; the efficacy of chitosans with viscosities of 57 and 360 cP was superior to that of chitosan with a 14 cP viscosity. Thus, chitosan as edible coating would enhance the quality of seafoods during storage. 相似文献
8.
Yasumi Yagasaki Takashi Chishima Masanori Okazaki Du-Sik Jeon Jeong-Hwan Yoo Young-Kull Kim 《Water, air, and soil pollution》2001,130(1-4):1085-1090
The effect of acidic deposition on the soil under red pine forest in Chunchon, Korea was investigated. Precipitation, stream water, and soil solution chemistry were monitored at the watershed from 1997 to 1998. Acidity of the open-bulk precipitation was often neutralized by large amounts of ammonia (NH3) that might have originated from livestock farming and fertilization. Estimated elemental budget at the watershed showed a positive correlation between loss of base cations and proton (H+) production due to nitrogen transformation in soil (ΔH+ NT: ([NH4 +]in-[NH4 +]out)- ([NO3 ?]in-[NO3 ?]out)). When ΔH+ NT increased, concentrations of nitrate in soil solutions also increased. Consequently, pH values of soil solutions decreased, although ion exchange with base cations contributed to buffer reaction. Since acid buffering capacity of the red pine forest soil was small, it was concluded that the input of ammonium nitrogen enhanced nitrification in soil thus causing soil acidification represented by loss of base cations from the watershed. 相似文献
9.
Multiple segmented reaches per subwatershed modeling approach for improving HSPF-Paddy water quality simulation 总被引:2,自引:0,他引:2
Ji-Hong Jeon Kyoung Jae Lim Chun G. Yoon Bernard A. Engel 《Paddy and Water Environment》2011,9(2):193-205
Reach segmentation influences predicted water quality concentrations in water quality modeling. Many lumped or semi-distributed
watershed models, including Soil and Water Assessment Tool (SWAT) and Hydrologic Simulation Program-Fortran (HSPF), simulate
stream/river water quality with a single segmented reach per subwatershed (SSRS) modeling approach. A multiple-segmented reaches
per subwatershed (MSRS) modeling approach was developed, and simulated BOD5 concentrations for this approach were compared with results from the SSRS modeling approach using the HSPF-Paddy model. The
SSRS modeling approach has potential systemic errors for predicting BOD5 concentration even when the model is well calibrated. When the point source was loaded at the most upstream location with
the same decay rate, the predicted BOD5 concentration using the SSRS modeling approach was higher compared with results for the MSRS modeling approach, and the difference
between two methods increases with increasing load and decay rate. When BOD5 was loaded more downstream, BOD5 concentration using the SSRS modeling approach was lower compared with results for MSRS modeling. For a case study, simulated
streamflow and BOD5 concentration for the SSRS and MSRS modeling approaches demonstrated good agreement with observed data. However, the estimated
decay rate for the SSRS modeling approach was smaller than that for the MSRS modeling approach because BOD decays through
total volume in the SSRS modeling approach, although BOD may be loaded anywhere in the reach. The MSRS modeling approach can
minimize systematic errors and provide more detailed variation of water quality concentrations along a river length. The MSRS
modeling approach does not always need to be applied to all subwatersheds but is recommended for reaches significantly polluted
by point source pollution. 相似文献
10.
Kwang Ho Sohn Min Kwan Kim So Min Lee Byung Chul Ji Kwang Soo Cho Kyungmoon Jeon Han Do Ghim 《Fibers and Polymers》2011,12(4):451-456
Triphenyl phosphate (TPP) is well known to be one of the most effective flame retardants for acrylonitrile-butadiene-styrene
copolymer (ABS) and its blending resins, such as polycarbonate (PC)/ABS, among various phosphorous-based compounds. However,
TPP can also play a role as a plasticizer, which decreases the mechanical properties of PC/ABS resins at high temperature.
Furthermore considerable amount of TPP has to be evaporated during molding process due on its much lower evaporation temperature.
To overcome these shortcomings, we tried to immobilize TPP by grafting on butadiene moiety of ABS. FT-IR analysis of prepared
TPP-grafted ABS (ABS-g-TPP) comparing with TPP, ABS and their blend confirmed that chemical reactions happened between TPP
and ABS resins and it was attributed to the graft reaction of TPP onto butadiene moieties. Prepared ABS-g-TPP resins were
blended with PC at various compositions to be prepared as testing specimens by injection molding. The physical characteristics
such as mechanical properties, thermal stability, and flame retarding properties of the PC/ABS-TPP graft copolymer were analyzed
through Vicat softening temperature, IZOD impact strength, transmission electron microscope, and UL94 flame retardation tests.
Results showed that PC/ABS-g-TPP resin takes better thermomechanical properties than the existing PC/ABS resins at relatively
low additional TPP amounts. 相似文献