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Brucellosis, caused by a facultative intracellular pathogen Brucella, is one of the most prevalent zoonosis worldwide. Host infection relies on several uncanonical virulence factors. A recent research hotpot is the links between carbon metabolism and bacterial virulence. In this study, we found that a carbon metabolism-related pyruvate kinase (Pyk) encoded by pyk gene (locus tag BAB_RS24320) was associated with Brucella virulence. Determination of bacterial growth curves and resistance to environmental stress factors showed that Pyk plays an important role in B. abortus growth, especially under the conditions of nutrition deprivation, and resistance to oxidative stress. Additionally, cell infection assay showed that Pyk is necessary for B. abortus survival and evading fusion with lysosomes within RAW264.7 cells. Moreover, animal experiments exhibited that the Pyk deletion significantly reduced B. abortus virulence in a mouse infection model. Our results elucidated the role of the Pyk in B. abortus virulence and provided information for further investigation of Brucella virulence associated carbon metabolism.  相似文献   
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Objective : The purpose of this study was to investigate whether implantable loop recorders could be used in the diagnosis of unexplained collapse in dogs. Methods : The medical records of six dogs presented to the University of Liverpool Small Animal Teaching Hospital between May 2003 and October 2006 for further evaluation of intermittent syncopal episodes, collapse or episodic weakness, were reviewed. All these dogs underwent standard investigations and had implantable loop recorders placed. Results : A provisional diagnosis of supraventricular tachycardia was made in one dog, and diagnoses of exclusion of arrhythmogenic right ventricular cardiomyopathy and idiopathic epilepsy was made in two dogs. One dog suffered no further syncopal episodes, a diagnosis was not reached in another dog and the final dog was lost to follow‐up. Clinical Significance : The implantable loop recorder can be used successfully for the diagnosis of unexplained collapse in dogs.  相似文献   
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应用动物模型REML法估计金华猪繁殖性状遗传参数   总被引:9,自引:0,他引:9  
试验资料取自金华猪场 1 979~1 999年金华猪繁殖性能的生产记录。采用动物模型约束性最大似然法 (REML)对该猪群的遗传参数进行估计 ,测定 1 1 4 4头纯繁金华母猪的产仔哺育记录。结果表明 ,产仔数 (TNB)、产活仔数 (NBA)、初生重 (PBW)、初生窝重 (LBW)、 2 0日龄头数(NFC)、 2 0日龄窝重 (LWFC)、 2 0日龄重 (PWFC)、 60日龄头数 (NW)、 60日龄窝重 (LWW)、 60日龄重 (PWW)、乳头数 (TN)的遗传力分别为0 1 2± 0 0 9、 0 1 8± 0 1 1、 0 1 5± 0 0 9、 0 0 2± 0 0 9、 0 1 0± 0 1 1、 0 0 8± 0 1 3、 0 1 8± 0 1 0、 0 2 3± 0 1 1、 0 31± 0 1 3、 0 35± 0 1 1和 0 1 9± 0 1 0。TNB与NBA、LBW、NW、LWW的遗传相关范围为 0 66~ 0 88,TNB与PBW的遗传相关为 - 0 43。NBA与LBW、NW、LWW的遗传相关范围为 0 60~ 0 64,NBA与PBW遗传相关为 - 0 63。PBW与PWW的遗传相关为 0 51。  相似文献   
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1. Observations of vigorous wing movements and measurements of bone strength were compared in two experiments with birds in three different housing systems: a semi-intensive alternative system under development, a battery cage system and a deep-litter system. 2. A significant effect of housing system on the frequency of vigorous wing movements was found. The highest frequency was seen in the deep-litter system, about half this number in the alternative system, while in the battery cages they were never observed. 3. Corresponding to this a reduction in humerus strength of 9% was found in hens from the alternative system and of 45% in hens from cages, compared with deep-litter. A reduction in tibial breaking strength was also found in caged hens, when compared to deep-litter hens. 4. Keeping hens in cages thus restricts their movements, especially wing movements, to the degree that bone strength is greatly reduced. 5. This has welfare implications, for hens with low bone breaking strength risk a possibility of breakage, especially when handled and transported. When alternative systems are designed opportunities for movement in the three dimensions should be considered.  相似文献   
47.
江苏省菜籽饼粕的抗营养因子含量分析   总被引:1,自引:0,他引:1  
收集华东省市当家的甘蓝型、白菜和芥菜型油菜籽品种20个,经105℃30分钟处理,小型62机冷榨取饼,测定OZT.ITC,得出甘蓝型高硫葡萄糖苷品种在饼中的总苷量最高9.36mg/g,比苷蓝型低硫葡萄糖苷品种含总苷2.95mg/G高出2倍。白菜型平均总苷3.13mg/g;芥菜型含3.56mg/g。以淮油6号、秦油2号菜籽作破碎或干热与否的前处理比较,总苷量以未破碎、未干热的菜饼最高,分别含9.82mg/g、10.64mg/g;破碎又干热的菜饼总苷最低,分别为8.69、7.01mg/g。以宁油7号品种为例用62型冷榨总苷最高为10.77mg/g,95型其次5.14mg/g,200型最低2.55mg/g。采集本省各地大、中、小型油厂、油坊的菜饼粕21个样,200型菜粕总苷为2.8mg/gcv45%,95型3.39mg/g,cv39.6%。200型与95型在加工过程中产生游离总苷量接近,分别为0.38和0.41mg/g。由芥子酶或酶水解产生的腈类化合物以200型的菜粕中含量高,平均含1318mg/kg,cv79.7%;95型含318mg/gcv132%,其中36%样本未检出腈量。菜饼粕单宁平均含0.82%;植酸平均?  相似文献   
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Proteomic analysis of mare uterine flush fluid provides a minimally invasive technique for studying protein changes associated with the oestrous cycle. The aim of this study was to identify differentially abundant proteins in the uterine flush fluid of mares in oestrus and dioestrus. In this study, uterine flush fluid samples were collected from eight reproductively healthy mares in either oestrus (n = 5) or dioestrus (n = 3). Proteomic analysis was performed using liquid chromatography‐tandem mass spectrometry. Of 172 proteins identified, six proteins (immunoglobulin lambda‐like polypeptide 1, haemoglobin subunit alpha, alpha‐1B‐glycoprotein, serotransferrin, apolipoprotein A‐1, and haemoglobin subunit beta) were significantly more abundant in oestrus. These proteins may contribute to the endometrial defence system through roles in inflammation, immunity or antimicrobial activity. In other species, some of these proteins have been described as immunoglobulins, negative acute phase proteins or defence agents against micro‐organisms. During dioestrus, immunoglobulin alpha‐1 chain C region‐related, complement factor I, CD 109 antigen and uterocalin, were significantly more abundant. Research in other species suggests that these four proteins contribute to the immune response through proposed immunoregulatory characteristics, complement system involvement or roles in B cell–T cell interactions. In conclusion, ten differentially abundant proteins were identified in the uterine flush fluid of mares in oestrus and dioestrus. Targeted studies on these proteins could elucidate their role in uterine defence mechanisms during the oestrous cycle in the mare.  相似文献   
50.
An adult great‐horned owl (Bubo virginianus; GHOW) presented with a history of recurrent corneal ulceration of the right eye (OD). Findings included ulcerative superficial keratitis, proliferative conjunctivitis, and iris pigmentary changes. The ulcer was initially nonresponsive to medical therapy, but showed rapid and appropriate healing following diamond burr debridement. Proliferative conjunctivitis markedly improved following topical antiviral therapy with cidofovir 1%, interferon alpha 2B ophthalmic solutions, and oral l ‐lysine. Histopathologic evaluation of a conjunctival biopsy revealed epithelial features suspicious for viral cytopathic changes and intranuclear structures suspicious for viral inclusions, suggestive of a possible viral‐induced papillomatous conjunctivitis. A novel alphaherpesvirus, referred to as Strigid Herpesvirus 1 (StrHV1), was identified using PCR and gene sequencing. This case represents a new clinical manifestation of a previously unreported herpesvirus in the GHOW. Identification of the herpes virus was critical to administration of appropriate therapy and resolution of the conjunctivitis, and corneal epithelial debridement promoted resolution of the chronic corneal epithelial defect.  相似文献   
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