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111.
Biliary sludge in dogs is dismissed commonly as an incidental finding. On the other hand, gallbladder mucocele is reported increasingly in dogs and can lead to biliary obstruction or gallbladder rupture. Cholestasis is suspected to play a role in development of sludge and mucoceles, though there are no data in dogs to support this. We investigated gallbladder emptying, a key factor in biliary flow, in dogs with mobile sludge, immobile sludge, or gallbladder mucocele and in healthy controls. Gallbladder ejection fraction estimated by ultrasonography was used as the index of gallbladder emptying. The ejection fraction at 60 min after eating was significantly decreased in all three abnormal groups. Moreover, all dogs with sludge or a mucocele had gallbladder distension. These changes were the greatest in the mucocele group. Thus, biliary stasis occurs not only in dogs with gallbladder mucocele but also in dogs with biliary sludge. Cholestasis may play a role in the pathogenesis or progression of these diseases in dogs.  相似文献   
112.
M. S. Kim    J. H. Kim    M. R. Lee    J. H. Kang    H. J. Kim    H. M. Ko    C. H. Choi    J. Y. Jung    J. T. Koh    B. K. Kim    H. K. Oh    W. J. Kim    E. J. Lee    S. H. Kim 《Anatomia, histologia, embryologia》2009,38(2):154-160
A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been reported to play a role in the degradation of aggrecan, a major component of cartilage. This study was performed to examine the effects of alendronate on the expression of ADAMTS in developing femoral epiphyseal cartilage. Primary cultured chondrocytes from this cartilage were treated with alendronate in vitro and postnatal day 1 rats were injected subcutaneously with alendronate (1 mg/kg) every second day in vivo . The number of cultured chondrocytes and their aggrecan mRNA levels were unaffected by the alendronate treatment at 10−6 to 10−4  m concentrations. The mRNA levels of ADAMTS-1, -2 and -9 in chondrocytes were also unaffected. However, the levels of ADAMTS-5 and -4 were reduced significantly by the same treatment. The thickness of the proliferating chondrocyte layers and the aggrecan mRNA levels in the epiphysis were unaffected by the alendronate treatment in vivo . However, the hypertrophied chondrocyte layers became significantly thicker, and the size of the secondary ossification centre was reduced significantly by the same treatment ( P  < 0.05). Both ADAMTS-4 and -5 mRNA expressions were also reduced significantly in vivo . The immunoreactivity against ADAMTS-4 was seen in hypertrophied chondrocytes and reduced significantly by the alendronate treatment. These results suggested that alendronate can inhibit the degradation of aggrecan in the articular cartilage by downregulating the expression of matrix enzymes such as ADAMTS-4 and -5.  相似文献   
113.
Infection with Likubin bacterium (LB) followed by Phytophthora parasitica increased the mortality of sour orange and pummelo seedlings, and enhanced the P. parasitica-induced root rot in all the four types of citrus tested. The LB-induced enhancement of root infection by P. parasitica was apparent within 1h of exposure to zoospore suspension. The enhancement of P. parasitica-induced root rot was affected by the infection sequence. Inoculation of sour orange seedlings with LB before P. parasitica was more effective in increasing P. parasitica-induced root rot than LB and P. parasitica concomitantly or LB after P. parasitica. Grafting P. parasitica susceptible scions of ponkan (Citrus reticulata) onto P. parasitica-tolerant rootstocks of sour orange greatly increased the susceptibility of rootstocks to P. parasitica. Results also demonstrate the enhancement of LB-induced symptoms by P. parasitica in citrus plants.  相似文献   
114.
Pelargonic acid (PA), an aliphatic 9-carbon monocarboxylic acid, is a phytotoxic burn-down compound. In the light peroxidizing activity can be measured as ethane and propane formation with cress or tobacco seedlings. This effect is strong at low pH (4–5), and saturated acids with 9–10 carbon atoms represent the optimum chain length. Methyl or ethyl esters are inactive, and safeners have no influence. In contrast to the peroxidative herbicides like acifluorfen methyl neither photosynthesis nor protoporphyrin IX is involved, although peroxidation requires light. Chlorophyll is necessary since etiolated seedlings show little peroxidation. Singlet oxygen quenchers like eugenol markedly reduce peroxidation. Membrane leakage of a similar rate is observed in light as well as in darkness. PA was described as a penetration enhancer intercalating with membranes. Our data corroborate that conclusion. Accordingly, the herbicidal mode of action of pelargonic acid is due first to membrane leakage in dark or light and second to peroxidation driven by radicals originating in the light by sensitized chlorophyll displaced from the thylakoids.  相似文献   
115.
1—甲基环丙烯延缓青花菜衰老的效应及机理   总被引:23,自引:0,他引:23  
 研究了1—甲基环丙烯(1-MCP)对青花菜衰老的影响。结果表明,0~20 µL/L的1-MCP在20℃下处理青花菜花球6 h,能延长2O 藏条件下苛仡菜的货架寿命,延缓花蕾中营养成分叶绿素、类胡萝卜素和维生素c等的降解,其中以2.5 µL/L处 的效果最佳。进一步研究还表明2.5 µL/L 1-MCP处理抑制花蕾的呼吸速率和乙烯释放速率,行使 藏期 花蕾的蛋白质含量升高;丙二醛(MDA)含量下降,使超氧化物歧化酶(SOD)和过氧化氧酶(CAT)的活性升高,过氧化物酶(POD)的活性下降,同时,SDS-PAGE分析表明,这一处理使花球中醇溶性蛋白和水溶性蛋白的组分和含量发生明显变化  相似文献   
116.
To assess the effects of slaughter weight and sex on APGS (Animal Products Grading Service) quality and APGS yield grade of Korean Hanwoo (n = 20,881) cattle, data were collected from cow, bull, and steer carcasses during a 1-yr period. Factors used to determine quality grade (marbling, meat color, fat color, texture, and overall maturity score) and yield grade (cold carcass weight, adjusted fat thickness, and longissimus muscle area) by the Korean grading system were recorded. Both yield and quality grades were improved (P < 0.01) with heavier slaughter weight, but there was no difference in yield grade for Hanwoo cattle classes heavier than 551 kg (P > 0.01). Longissimus muscle area, adjusted fat thickness, and marbling score increased (P < 0.01) with carcass weight. Bull carcasses showed higher yield but lower quality than those of cows or steers (P < 0.01). The quality grade of steer carcasses was higher (P < 0.01) than that of cow carcasses due to higher marbling scores, lower maturity scores, and heavier carcass weights. Hanwoo carcasses with larger longissimus muscle areas in relation to their carcass weight had lower APGS quality grades. The APGS quality grades were different between yield grade A and B carcasses (P < 0.01), but quality grade was not improved by increased fat thickness beyond the point of yield grade B. Adjusted fat thickness and marbling score showed significant (P < 0.01) differences among all yield grade classes, and this resulted in increased quality grade as yield grade decreased. Adjusted fat thickness showed the strongest correlation (r = -0.63) with yield grade, whereas marbling score had the strongest correlation (r = 0.81) with quality grade. Results showed a negative effect of castration on yield but a positive effect on quality. Also, data showed that Hanwoo carcasses with heavier weights had higher quality grades than those of lighter weight.  相似文献   
117.
At present the use-rate of modern herbicides is in the range of 100-300 g AI ha-1, with a tendency to decline. The low use-rate (ca 10 g AI ha-1) of the original sulfonylurea and cyclic imide herbicides prompted agrochemical scientists to look for even more active compounds which led to the successive discoveries of many new herbicidal acetolactate synthase inhibitors and no less than 18 cyclic imides in the class of protoporphyrinogen-IX oxidase inhibitors in the 1990s. In this paper, mechanisms of action related to function and biosynthesis of chlorophylls, carotenoids, plastoquinone, amino acids, fatty acids and photosynthetic electron transport and other metabolic processes are discussed as plant-specific herbicidal target domains.  相似文献   
118.
Lidocaine patches have been used to provide local analgesia in dogs and cats. We conducted this study to assess the systemic and local absorption of lidocaine from topical patches in cats. Eight 2-year-old cats received either intravenous lidocaine at 2 mg/kg or one 700 mg lidocaine patch placed on the lateral thorax for 72 h, in a cross-over randomized repeated measures design. Plasma was collected at specific times and the skin was biopsied at the time of patch removal for the quantitative analysis of lidocaine and its major metabolite, monoethylglycinexylidide (MEGX), by gas chromatography with mass spectrometry. Percent absorption time plots for systemic lidocaine appearance were constructed using the Loo-Riegelman method. Approximately, constant rate absorption was observed from 12-72 h after patch application at a mean +/- SD rate of 109 +/- 49 microg/kg/h, resulting in steady-state lidocaine plasma concentrations of 0.083 +/- 0.032 microg/mL and MEGX concentrations of 0.012 +/- 0.009 microg/mL. Overall bioavailability of transdermal lidocaine was 6.3 +/- 2.7%, and only 56 +/- 29% of the total lidocaine dose delivered by the patch reached systemic circulation. Skin lidocaine concentrations were much higher than plasma concentrations, at 211 +/- 113 microg/g in the thoracic skin beneath the patch and 2.2 +/- 0.6 microg/g in the contralateral thoracic skin without the patch. As both lidocaine and MEGX were recovered from contralateral skin, it is likely that lidocaine accumulated in the skin from low systemic concentrations of circulating lidocaine over the 72-h period of patch application. Plasma lidocaine concentrations remained well below systemically toxic concentrations, and no obvious clinical side effects were observed in any of the cats. The low systemic absorption rate coupled with high local lidocaine concentrations on the skin support the safe use of lidocaine patches in cats.  相似文献   
119.
Atopic dermatitis (AD) is a chronic inflammatory skin disease in which skin barrier dysfunction leads to dryness, pruritus, and erythematous lesions. AD is triggered by immune imbalance and oxidative stress. Echinochrome A (Ech A), a natural pigment isolated from sea urchins, exerts antioxidant and beneficial effects in various inflammatory disease models. In the present study, we tested whether Ech A treatment alleviated AD-like skin lesions. We examined the anti-inflammatory effect of Ech A on 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesions in an NC/Nga mouse model. AD-like skin symptoms were induced by treatment with 1% DNCB for 1 week and 0.4% DNCB for 5 weeks in NC/Nga mice. The results showed that Ech A alleviated AD clinical symptoms, such as edema, erythema, and dryness. Treatment with Ech A induced the recovery of epidermis skin lesions as observed histologically. Tewameter® and Corneometer® measurements indicated that Ech A treatment reduced transepidermal water loss and improved stratum corneum hydration, respectively. Ech A treatment also inhibited inflammatory-response-induced mast cell infiltration in AD-like skin lesions and suppressed the expression of proinflammatory cytokines, such as interferon-γ, interleukin-4, and interleukin-13. Collectively, these results suggest that Ech A may be beneficial for treating AD owing to its anti-inflammatory effects.  相似文献   
120.
Model reactions with various -SH, -OH and -NH nucleophiles in an aprotic solvent were used to characterise the nature of the enzymatic conversion of thiadiazolidines to triazolidines. This conversion results in greater inhibition of protoporphrinogen oxidase (protox). It is inferred that GST-isoforms probably promote formation of one of the intermediates.  相似文献   
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