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Objective: To determine the effect of storage on the P50 of feline hemoglobin. Design: Prospective, in vitro, laboratory study. Subjects: Venous blood from 4 clinically healthy cats. Measurements: Blood was collected into CPDA‐1 anticoagulant/preservative and maintained at 4°C for 5 weeks. Measurements were made on Days 0, 2, 4, 7, 14, 21, 28, and 35. The blood samples were equilibrated in a tonometer to gas mixtures containing 2.5%, 4%, 5%, or 8% oxygen, with 5% carbon dioxide balance nitrogen; pH was adjusted to 7.4. Chloride, partial pressure of oxygen, and hemoglobin saturation were measured; P50 was calculated. Results: Chloride decreased from 124.3±2.1 to 88.5±1.9 mEq/L immediately after dilution with CPDA‐1, and did not change for the 5 weeks thereafter. The P50 decreased from an average of 35.0±1.2 to between 31 and 32 mmHg after 7 days, and did not change further for 4 weeks thereafter. Conclusions: The decrease in P50 of feline hemoglobin was minor compared with that of blood from species in which 2,3‐diphosphoglycerate (2,3‐DPG) is a major modifier of hemoglobin affinity for oxygen. The decrease in P50 in the present study was attributed to an initial decrease in chloride and a subsequent loss of modest quantities of red cell 2,3‐DPG.  相似文献   

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Epoxomicin potently and irreversibly inhibits the catalytic activity of proteasomal subunits. Treatment of proliferating cells with epoxomicin results in cell death through accumulation of ubiquinated proteins. Thus, epoxomicin has been proposed as a potential anti-cancer drug. In the present study, the inhibitory effects of epoxomicin on the in vitro growth of bovine and equine Babesia parasites were evaluated. The inhibitory effect of epoxomicin on the in vivo growth of Babesia microti was also assessed. The in vitro growth of five Babesia species that were tested was significantly inhibited (P < 0.05) by nanomolar concentrations of epoxomicin (IC50 values = 21.4 ± 0.2, 4 ± 0.1, 39.5 ± 0.1, 9.7 ± 0.3, and 21.1 ± 0.1 nM for Babesia bovis, Babesia bigemina, Babesia ovata, Babesia caballi, and Babesia equi, respectively). Epoxomicin IC50 values for Babesia parasites were low when compared with diminazene aceturate and tetracycline hydrochloride. Combinations of epoxomicin with diminazene aceturate synergistically potentiated its inhibitory effects in vitro on B. bovis, B. bigemina, and B. caballi. In B. microti-infected mice, epoxomicin caused significant (P < 0.05) inhibition of the growth of B. microti at the non-toxic doses of 0.05 and 0.5 mg/kg BW relative to control groups. Therefore, epoxomicin might be used for treatment of babesiosis.  相似文献   

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Glucocorticoids are known to hinder somatic growth in a number of vertebrate species. In order to better understand the mechanisms through which they may act in channel catfish, we examined the effects of feeding cortisol on the growth hormone (GH)/insulin-like growth factor-I (IGF-I)/IGF-binding protein (IGFBP) network. Fish (30.6 ± 3.0 g) were fed once daily for 4 weeks and treatments included: (1) High-cortisol (dietary cortisol provided at 400 mg/kg feed), (2) Low-cortisol (dietary cortisol provided at 200 mg/kg feed), and (3) Control (commercial catfish feed). Fish fed diets with cortisol weighed approximately 50% less than Controls. Feed intake was reduced by approximately 30% in both treatments of cortisol fed fish compared to Controls. A 20-kDa IGFBP was observed in plasma from High- and Low-treated fish while it was not detected in Control fish plasma. High-cortisol treatment increased pituitary GH mRNA expression approximately 10-fold while liver IGF-I mRNA expression was not different between cortisol-treated fish and Controls. Cortisol treatments decreased plasma levels of IGF-I. These data indicate that feeding cortisol for 4 weeks reduces weight gain, feed intake, and plasma levels of IGF-I and induces a 20-kDa IGFBP. One mechanism through which cortisol may impede growth of catfish is through an increase in a low molecular weight IGFBP which may lead to inhibitory effects on the action of IGF-I.  相似文献   

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Multiple regression analyses were used to investigate the ecological determinants and the population dynamics oof bovine leptospirosis in Queensland between 1972 and 1983. Analyses were performed using leptospiral herd sero-prevalences, weather, soil and animal population data.

Leptospira interrogans serovars pomona and hardjo overlapped in 57% of geographical locations for which herd sero-prevalences were available. The main ecological determinants for L. pomona in Queensland appear to be low relative humidity, Typic Torrert clays in the soil, the presence of feral pigs and the average maximum temperatures for the region. For L. hardjo the main determinants are not as clearly defined but appeat to include the presence of beef cattle, the average minimum temperatures, alkaline trend in duplex soils, presence of beef Typic Torrert and absence of Typic Pellustert clays.

There was a major sustained high level of herd leptospiral sero-prevalence in the first 5 years of the study. A comparison of data from this period and the second 5 years suggests that the increase in herd sero-prevalence was caused by the release of free leptospires from the Vertisol clays nto the water tables following heavy rainfall. The leptospires could then infect susceptible cattle and/or maintenance hosts.  相似文献   


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The age of the sheep donating neutrophils had a marked influence in vitro on their phagocytic ability with respect to Staphylococcus aureus and S aureus subspecies anaerobius. Neutrophils from lambs five to eight weeks old phagocytosed these organisms significantly less efficiently (P<0–001) than neutrophils from adults two to four years old. However, neutrophils from the young animals phagocytosed S aureus significantly (P<0·001) better than S aureus subspecies anaerobius (61·5 v 53·8 (per cent), whereas there was no significant difference in the ability of the neutrophils from adult sheep to phagocytose S aureus and S aureus subspecies anaerobius (68·2 v 68·2 per cent).  相似文献   

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协调人与野生动物矛盾的法律探讨   总被引：1，自引：0，他引：1  
黄锡生  关慧 《野生动物》2006,27(1):35-37
野生动物保护意识的增强，生物多样性保护工作的推进，为野生动物的栖息繁衍提供了有利的条件。与此同时，野生动物肇事屡有发生，人与野生动物矛盾日益突出。确立有效协调人与野生动物的矛盾的新机制，在保护国家珍稀野生动物的同时保护群众合法利益，才是野生动物保护事业和可持续发展的长久之计。  相似文献   

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Prostaglandin E1 was infused intravenously (25, 50 and 75 ng/kg/min) in three ponies. Changes in gastrointestinal mechanical and electrical activity were recorded from chronically implanted strain-gauge force transducers and electrodes. Dose-dependent responses were obtained: there were significant decreases in electrical spiking activity in the stomach, left large colon and small colon, with a corresponding decrease of activity in the left dorsal colon mechanogram. The small intestine was also affected, showing a decrease in both contraction rate and amplitude, which was more marked in the proximal jejunum than in the ileum. There was an association between these changes in gastrointestinal activity and the presence of discomfort and diminished gut sounds.  相似文献   

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The new Directive 2010/63/EU on the protection of animals used for scientific purposes causes a need of several changes in German animal welfare law. On the basis of the regulations in the Directive, adjustments of the existing notification procedures are unavoidable. The Directive includes provisions for a simplified administrative procedure which differs significantly from the existing notification procedures. In any case, an application process will be required for projects in the meaning of the Directive. This contribution comments on the conceivable changes of the existing notification procedure. The implementation of the provisions of the Directive into national law has to be done near-term as the Directive is applicable from January 1st 2013. In advance, political and legal procedures must be passed through, the adapted regulations are to be notified by the European Commission and last but not least the authorities and user establishments must have enough time to implement the necessary changes.  相似文献   

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本文通过鸡胚接种的方法就蜂胶乙醇浸出物对禽流感H9亚型Shandong／chicken／98株的灭活作用进行了研究。结果表明，常温下3分钟、30分钟，37℃3分钟、30分钟，含蜂胶乙醇浸出物0．1mg/mL的95％乙醇稀释液，含蜂胶乙醇浸出物2．5mg／mL的47．5％乙醇稀释液。含蜂胶乙醇浸出物10mg/mL的生理盐水稀释液，接种鸡胚后病毒HA测定为0。这充分说明以上浓度蜂胶乙醇浸出物对禽流感H9亚型Shandong／chicken／98株具有完全的灭活作用。37℃3分钟、30分钟，含蜂胶乙醇浸出物0．1mg／mL的47．5％乙醇稀释液，含蜂胶乙醇浸出物6．25mg/mL的生理盐水稀释液对禽流感H9株有部分灭活作用。  相似文献   

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本研究旨在揭示肌抑素（MSTN）与基质金属蛋白酶（MMPs）的调控关系,探明MSTN对PK15细胞MMP-2/7/9表达的影响。对MSTN单等位基因敲除猪背膘组织进行转录组测序分析,复苏前期制备的MSTN基因敲除PK15细胞系：单等位基因敲除的PK3108细胞系和双等位基因敲除的L18细胞系,通过实时荧光定量PCR和Wesrern blotting分别检测PK15、PK3108和L18细胞系中MSTN、MMP-2/7/9基因的mRNA和蛋白表达水平。结果发现,与野生型猪相比,MSTN单等位基因敲除猪背膘组织转录因子C/EBPδ、MMP-2/7基因mRNA表达量均极显著下调（P < 0.01）;细胞外基质中纤连蛋白（FN）和层连接蛋白（LN）含量均极显著增加（P < 0.01）。复苏的PK3108和L18细胞呈现绿色荧光。实时荧光定量PCR结果显示,PK3108和L18细胞中MSTN、MMP-2/7/9的mRNA表达量均极显著低于PK15细胞（P < 0.01）;Western blotting结果显示,PK3108和L18细胞中MSTN、MMP-2/7/9的蛋白表达量均明显低于PK15细胞。本研究结果表明,在MSTN基因敲除的PK15细胞中,MSTN功能缺失能显著降低MMP-2/7/9的表达,且MMP-2/7/9蛋白表达降低的趋势与MSTN蛋白表达的趋势相一致。  相似文献   

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为了研究Thl/Th2型细胞因子的动态变化对山羊妊娠的影响,探讨其生理学意义,试验通过ELISA方法对山羊妊娠早期及流产前后外周血液中Thl(TNF-α、IL-2)与Th2(IL-10)型细胞因子的含量进行了检测.结果表明:妊娠早期外周血液中TNF-α和IL-2含量先升高后降低,IL-10量持续上升;流产后TNF-α和IL-2含量高于流产前含量(P<0.01或P<0.05),IL-10则低于流产前含量(P<0.05或P<0.01).说明山羊正常妊娠时Th1/Th2型细胞因子动态平衡应当是以Th2型免疫及其相关因子占优势,平衡失调则导致妊娠失败.  相似文献   

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Based on earlier studies with mice and pigs, the possible pleiotropic effects of the individual porcine Dominant White/KIT genotypes on the size, histological parameters, and surface features of the ovaries; on the size, histological characteristics, and volume of the testes; and on the occurrence of abnormal epididymal sperm cells were studied in two F2 generations of an intercross between Hampshire boars and Hungarian Large White sows. The KIT genotypes were determined by a PCR-RFLP method. The ovarian diameters of gilts of various KIT genotypes did not differ significantly (P=0.292), and the II pigs had the smallest diameters. The proportion of the investigated follicular types among the different KIT genotypes did not differ significantly (P=0.329-0.919), and the highest numbers of degenerated and atretic follicles were found in the ovaries of II genotype pigs, which also exhibited the highest proportion of primary follicles. The testis volume in the II homozygote white genotype boars (249.5 cm(3)) was significantly (P<0.01) larger than in the Ii (205.4 cm(3)) and ii (197.5 cm(3)) boars. Bodyweight and age significantly (P<0.01) affected testicular volume. KIT genotypes had no profound effect on the proportion of the various epididymal sperm abnormalities, and ii type boars showed the highest (nonsignificant) numbers of primary abnormalities. The changes in abnormal sperm cell frequency were linear to the changes in bodyweight and testis volume. We were unable to demonstrate disadvantageous effects of the KIT genotypes on the investigated ovarian, testicular, and epididymal sperm characteristics. Therefore the reproductive traits of white colored pigs examined in this study are no worse than those of pigmented breeds.  相似文献   

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The bovine digital vasculature contractility has been implicated in the development of laminitis. To investigate the effect of hypoxia/reoxygenation on the contractility of isolated peripheral bovine digital veins (BDVs), vessel rings were studied under isometric conditions and submitted to 30 min of hypoxia (95%N(2)-5%CO(2)) and reoxygenation (95%O(2)-5%CO(2)) conditions, respectively. The BDVs contracted with a high K(+) depolarizing solution, developed hypoxia-induced relaxation, followed by an increase in tension upon reoxygenation. In contrast, phenylephrine-contracted BDVs displayed a rapid, sustained and reversible hypoxia-induced contraction. Reoxygenation caused a rapid relaxation in phenylephrine-contracted BDVs. The presence of the endothelium did not modify the hypoxia/reoxygenation effects and hypoxia-induced contraction was still observed in a nominal Ca(2+)-free Krebs, however, the last effect was not maintained over time. The hypoxia-induced contraction in an isolated peripheral vein may contribute to the understanding of the physiology and pathophysiology of superficial venous smooth muscle contractility, particularly in the alteration of bovine digital haemodynamics under hypoxia/reoxygenation conditions.  相似文献   

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OPG/RANKL/RANK系统的研究进展   总被引：5，自引：0，他引：5  
OPG/RANKL/RANK系统是近年来骨科研究领域中的重大突破,研究发现许多激素、细胞因子等均通过直接或间接的调节骨保护素(osteoprotegerin,OPG),核因子-κB受体活化因子配体(receptor activator ofNF-κB ligand,RANKL)的表达,调控OPG、RANKL和核因子-κB受体活化因子(recep-tor activator of NF-κB,RANK)之间的比例,从而介导破骨细胞的分化和功能而达到抗骨质疏松或致骨质疏松的作用。现就OPG/RANKL/RANK系统在骨质疏松中的作用做一综述。  相似文献   

18.
基于EOS/MODIS的亚像元火情监测方法   总被引：3，自引：0，他引：3  
利用对比监测卫星(Earth Observing Satellites,EOS)和中分辨率成像光谱仪(Moderate Resolution Imaging Spectroradiometer,MODIS)资料多波段和多空间分辨率的优势,研究了在混和像元中分解出亚像元火点,建立不同红外波段混和像元二元非线性方程表达式,利用牛顿迭代法求解亚像元火点的面积和亮度温度.通过对2002-2004年的我国西北地区典型火情进行估算,可以认为,该方法为小火点和扑灭后的余火估算提供了一种有效的途径.  相似文献   

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The present study aims to characterize the main morphological changes occurring on the bovine ruminal papillae during pre- and postnatal development. Light microscopic observations of the ruminal wall from bovine fetus (3 to 9 month fetal age) and from crossbreed (Holstein-Frisian) calves (5 to 60 days-old) were analysed. The results suggest that the postnatal papillary development corresponds mainly to a fully actualization of the differentiation pattern already developed at the prenatal stage.  相似文献   

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