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11.
1. Apparent MEn and oil digestibility of hulled sunflower seed (SFS) and the products derived from the oil extraction process: press extracted SFS (PESFS), sunflower seed meal (SFSM), and press and solvent oils (PO and SO) were determined with 198 cockerels. Recombined products (mix of meal and oil) were also evaluated to study the effect of the 2 consecutive oil extraction steps. Each foodstuff was included in a basal diet, according to the proportions resulting from processing, at 100, 200, and 300 g SFS/kg. 2. Dietary energy value and digestible fat content were linearly related to rate of inclusion of test ingredients. Extrapolation values for AMEn (MJ/kg DM) were: SFS, 16.20; PESFS, 9.46; SFSM, 7.62. A decreasing quadratic trend was also found in the AMEn of PESFS, with interpolation values ranging from 11.77 to 9.33 MJ/kg DM between 70 and 210 g/kg DM of inclusion. No differences were observed between PO and SO. The AMEn of of sunflower oil, calculated from its digestibility, was 33.70 MJ/kg DM. 3. The oil extraction process affected the nutritional value of sunflower products. Recombined materials showed greater values than original foodstuffs: R-SFS, 17.47; R-PESFS, 11.49 MJ/kg DM. The increase in oil digestibility (from 0.814 to 0.862 g/kg DM in SFS; from 0.778 to 0.892 in PESFS) accounted for most of the increase observed in AMEn values. 4. As the form in which oil is incorporated in diets (released or within SFS or PESFS) affects the utilisation of sunflower products, their nutritional value is less than maximal and should not be calculated from their ingredients. Solvent oil seems to be the less available fraction of sunflower oil within SFS as the effect of the 2nd extraction proved to be greater than that of the previous press extraction.  相似文献   
12.
本研究目的在于制备抗猪带绦虫TSOL18单克隆抗体,并分析单抗对六钩蚴的杀伤作用。采用SephadexG-100纯化在毕赤酵母中表达的猪带绦虫六钩蚴TSOL18蛋白;纯化的蛋白免疫BALB/c小鼠,运用杂交瘤技术建立能分泌抗TSOL18单克隆抗体的细胞株;通过ELISA叠加试验进行mAb的抗原表位分析;采用间接ELISA法测定TSOL18单克隆抗体特异性及腹水效价;采用抗TSOL18单克隆抗体对激活的猪带绦虫六钩蚴进行体外六钩蚴杀伤试验,观察单抗对猪带绦虫六钩蚴活力的影响。结果成功获得12株稳定分泌抗TSOL18单克隆抗体的杂交瘤细胞株,识别2个不同抗原表位,不同抗原表位的2株单克隆抗体腹水效价分别为1×102、1×106。抗体体外六钩蚴杀伤试验结果证明,在有补体的情况下,多抗和单抗作用6 d后,六钩蚴结构模糊,边缘不清晰。表明单抗对六钩蚴有一定的杀伤作用。  相似文献   
13.
本研究以在毕赤酵母系统中表达并纯化的p27重组蛋白为包被抗原,HRP标记的兔抗鸡IgY为酶标二抗,建立了一种快速有效的禽蛋白血病病毒ELISA检测方法,并对其反应条件进行优化。结果显示,该方法具有良好的特异性和重复性;与市售商品试剂盒相比,符合率为96.92%,且更为敏感。应用建立的ELISA方法检测来自吉林省内鸡场314份疑似样品,阳性检出率为75.15%。本研究为禽白血病病毒的检测与诊断提供了一种简便、有效的检测方法。  相似文献   
14.
15.
mcr-1基因是研究细菌耐药机制时从耐药菌株中发现的一种质粒介导的多黏菌素类耐药基因,mcr-1的发现突破了对耐药机制的认知,随着研究的深入,更多机制被揭示,其变异体也被发现.论文就mcr基因的分布及传播和引起多黏菌素耐药机制,与人、动物环境的关系和传播风险等进行了综述,以期能够对多黏菌素耐药性的认识和mcr基因的研究...  相似文献   
16.
OBJECTIVE: To compare the microstructural damage created in bone by pins with lathe-cut and rolled-on threads, and to determine the peak tip temperature and damage created by positive-profile external fixator pins with either hollow ground (HG) or trocar (T) tips during insertion. STUDY DESIGN: An acute, in vitro biomechanical evaluation. SAMPLE POPULATION: Twenty-seven canine tibiae. METHODS: Lathe-cut thread design with T point (LT-T), rolled-on thread design with T point (RT-T), and rolled-on thread design with HG point (RT-HG) pins were evaluated. Twenty pins of each type were inserted under constant drilling pressure into 12 canine tibiae (12 diaphyseal and 8 metaphyseal sites per pin type). Peak pin tip temperature, drilling energy, end-insertional pin torque, and pullout force were measured for each pin. For the histologic study, five pins of each type were inserted into cortical and cancellous sites in 15 additional tibiae. Entry and exit damage, and thread quality were assessed from 100 micron histologic sections by using computer-interfaced videomicroscopy. RESULTS: T-tipped pins reached higher tip temperature in both diaphyseal and metaphyseal bone compared with HG-tipped pins. RT-T pins had higher pullout strength (diaphyseal) and end-insertional torque compared with other combinations. No differences in drilling energy or insertional bone damage was found between the three pin types (P < .05). CONCLUSIONS: T-tipped pins mechanically outperformed HG-tipped pins. Pin tip and thread design did not significantly influence the degree of insertional bone damage. CLINICAL RELEVANCE: T-tipped pins may provide the best compromise between thermal damage and interface friction for maximizing performance of threaded external fixator pins.  相似文献   
17.
史娟  王华荣  钟少林 《草业学报》2012,21(5):122-127
从细胞角度揭示苜蓿假盘菌与苜蓿叶片亲和性互作机制。以两者亲和性互作系统为研究材料,利用透射电子显微镜技术研究了苜蓿假盘菌与苜蓿叶片亲和性互作的超微结构特征。结果表明,病菌侵入寄主组织后,菌丝直接穿透寄主细胞壁进入寄主细胞形成胞内菌丝,以胞内生长并向相邻细胞扩展。病菌菌丝穿透寄主细胞壁时,菌丝中的液泡给予了较大的压力帮助其穿透。进入寄主细胞内的病菌菌丝,被内陷的寄主原生质膜包裹,菌丝与质膜始终是隔离的,寄主原生质膜和细胞壁之间沉积电子致密度深的物质。病菌菌丝不断地在寄主原生质膜区域扩展,伴随菌丝体在寄主细胞内的不断扩大,周围的原生质膜也相应扩大其面积,但始终将寄主原生质与菌丝体隔开,而脱离质膜的菌丝形成菌丝鞘包裹。随侵染程度的增加,未被穿透的寄主原生质膜区域逐步被降解。病菌侵染叶绿体等细胞器时,首先是菌丝鞘与叶绿体等细胞器膜相连,然后降解其基粒片层结构,被降解的细胞器组织沿菌丝和胞壁周围沉积。侵染后期,菌丝胞内和胞外扩展,但处在细胞降解物中的菌丝显示较厚的细胞壁,寄主细胞内充满了大量的黑色物质和结晶状的颗粒物。  相似文献   
18.
The impact of an efflux pump-related interaction between ivermectin and danofloxacin on their intestinal transport (ex vivo) and disposition kinetics (in vivo) was assessed. Eighteen male Corriedale sheep were randomly assigned to one of three groups. Animals in Group A received 0.2mg/kg ivermectin by SC injection, those in Group B were given 6 mg/kg danofloxacin SC on two occasions 48 h apart and those in Group C were treated with both compounds at the same rates. Plasma concentrations of ivermectin and danofloxacin were measured by HPLC using fluorescence detection. Ex vivo intestinal drug transport activity was measured by the use of the Ussing chamber technique. Plasma concentrations of ivermectin in the first 6 days after injection tended to be higher in Group C than Group A. Contemporaneous treatment with ivermectin significantly increased systemic exposure to danofloxacin (AUC values were 32-35% higher) and prolonged the elimination half-life of danofloxacin (40-52% longer). Ex vivo, incubation with ivermectin significantly decreased the efflux transport of rhodamine 123, a P-glycoprotein substrate, in sheep intestine, but no significant effect of danofloxacin on transport activity was observed. Evaluation of the interaction of danofloxacin with the breast cancer resistance protein (BCRP) showed that pantoprazole and ivermectin significantly decreased danofloxacin secretion in the rat intestine. Thus, the ivermectin-induced reduction of danofloxacin efflux transport observed in this study may involve BCRP activity but the involvement of P-glycoprotein cannot be ruled out.  相似文献   
19.
试验旨在优化Smad泛素化调节因子2(Smurf2) siRNA最佳转染条件,筛选最佳siRNA干扰片段,进而实现对Smurf2基因的瞬时沉默,为研究Smurf2基因在马兜铃酸肾病(aristolochic acid nephrohathy,AAN)中的作用奠定基础。本研究通过培养小鼠原代肾小管上皮细胞(renal tubular epithelial cells,RTECs),并以脂质体LipofectamineTM 2000为转染介质,将Smurf2 siRNA转染入RTECs;通过观察绿色荧光的表达量及Real-time PCR反应优化转染条件,转染后Real-time PCR检测mRNA表达抑制率。CCK-8法检测Smurf2 siRNA复合物对RTECs活性的影响;同时,用Real-time PCR和Western blotting检测不同位点Smurf2 siRNA对Smurf2 表达的影响。结果显示,当Lipofectamine TM 2000与siRNA比例为1.5 μL∶30 pmol时,转染效率最高,为70%~80%;Smurf2-619 siRNA干扰效果最明显;与正常组相比,转染siRNA组的Smurf2蛋白表达水平显著下降(P<0.05)。最终确定了Smurf2 siRNA最佳转染条件,其中Smurf2-619 siRNA对Smurf2 表达的抑制率最高。  相似文献   
20.
Salmonella and Yersinia are important enteropathogens in poultry and can affect birds of all ages, including embryos. These food-borne zoonotic enteropathogens are of great economic and medical concern worldwide and are intensely studied in poultry. Information regarding the prevalence of these bacteria in wild birds is scarce and biased toward avian species ecologically linked to humans, which have often been incriminated as both reservoirs and disseminators of these enteropathogens. The prevalence of Salmonella and Yersinia recovered from both the feces and eggs in a population of female pied flycatchers (Ficedula hypoleuca) breeding in nest-boxes in central Spain was evaluated. Salmonella arizonae was recovered from the feces of one female but was not recovered from eggs. Yersinia was not detected in either the feces or eggs. These results may suggest that Salmonella and Yersinia may be uncommon in this population studied and may indicate that these birds are unlikely reservoirs of Salmonella and Yersinia.  相似文献   
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