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511.
512.
Using an ELISA test with specific equine antisera, resting and post-exercise serumIgE concentrations were determined in 20 horses exhibiting varying degrees of exercise- induced pulmonary hemorrhage (EIPH), and in 10 horses identified endoscopically as non-bleeders.

Significantly higher serum IgE concentrations (P<0.01) were present in horses which bled profusely than in those which bled mildly or not at all. Reductions in serum IgE concentrations were evident following exercise in most horses and, even though these reductions were not statistically significant, this suggested the possibility that circulating IgE had become bound to basophils or to bronchial mast cells as a result of the exercise.  相似文献   

513.
作物生态气候滑移相似离度分析方法综合了生物气候滑移相似分析和相似离度分析的优点,使作物生态气候相似分析更为准确。以河西走廊酿酒葡萄生态气候适生种植区划为例对该方法进行了应用验证,发现它能较准确地反映不同酿酒葡萄适生种植区之间热量条件、灌溉条件等的生态气候差异。  相似文献   
514.
Pigs born outdoors and reared on deep litter (straw) have been reported to experience less of a growth check after weaning and have a higher dressing percentage than counterparts born and reared under conventional (indoor) systems. The reason(s) for this difference is/are presently unknown, but differences in the gut environment might contribute to these observations. PCR-DGGE techniques were used in this study to examine microbial diversity and banding patterns in the large intestine of piglets that were reared under different rearing conditions. Six piglets per treatment were euthanised at weaning (21 days) and at 7 days and 21 days after weaning from two extreme treatments [indoor-born: conventionally-raised after weaning (‘Indoor’) or outdoor-born, deep-litter raised after weaning (‘Outdoor’)]. The Shannon diversity index was calculated, and multivariate analysis of banding patterns was performed. Indoor pigs had a more diverse bacterial population at weaning and 21 days after weaning than Outdoor pigs. However at the end of the first week after weaning, outdoor-born and deep-litter pigs had a more diverse microbiota. The Shannon diversity index continued to increase with time after weaning in Outdoor pigs, which did not occur in Indoor pigs. Multivariate analysis of banding patterns showed there was a trend (P = 0.109) for a difference in microbial structure depending on housing type. There was also a significant (P < 0.001) effect of sampling time after weaning and a significant interaction (P < 0.001) between housing and time after weaning.  相似文献   
515.
This study investigated the effects of weaning age, diet, and classification of piglets as ‘eaters’ or ‘non eaters’ of creep feed in lactation, on production and diarrhoea after weaning. Four antimicrobial-free diets were offered in lactation and for 14 days after weaning: (i) wheat–soy based diet with animal and vegetable (‘mixed’) protein sources (COMM), (ii) heat-processed rice (HPR) with barley hulls and potato starch and mixed protein sources (RBHPS), (iii) HPR with sugar-beet pulp and mixed protein sources (RSBP), and (iv) HPR with mixed protein sources (R). Piglets were individually examined for diarrhoea daily for 14 days after weaning, and antibiotic treatments were individually recorded. Faecal swabs were taken on day 10 after weaning and scored for β-haemolytic Escherichia coli. There were significant main effects of weaning age and diet (both P < 0.001) on daily gain between weaning and 14 days after weaning. Pigs weaned later grew 50 g/day more than pigs weaned earlier, and pigs fed the COMM diet grew slower than pigs fed the rice-based diets. The number of antibiotic treatments was influenced by diet (P < 0.001), with most treatments (2.1) given to pigs fed the diet RBHPS. Faecal score was influenced by a weaning age and diet interaction (P < 0.01). There was no correlation (P > 0.05) between the number of antibiotics treatments and the E. coli score.  相似文献   
516.
Stephan  Kaiser  DVM  MS  Daniel  Cornely  MD  Werner  Colder  MD  PhD  Michael T.  Garner  BA  CVM  K.-J. Wolf  MD  PhD  Helmut  Waibl  DVM  PhD  Leo  Brunnberg  DVM  PhD 《Veterinary radiology & ultrasound》2001,42(2):113-118
Measurements from magnetic resonance (MR) images can be used to examine the anteversion angle (AT-angle) and its influence on the lateromedial or mediolateral luxating forces on the patella. The AT-angle of the femoral neck was measured with the aid of MR imaging in 45 pelvic limbs without patellar instability, in 33 limbs with patellar luxation and in 6 limbs with rupture of the cranial cruciate ligament. The limbs with medial patellar luxation were divided into three groups based on clinical examination. The mean (range) AT-angle was 7.6 degrees (0 degrees to 24 degrees) in the "normal" group, 8.6 degrees (-10 degrees to 29 degrees) in the group "grade II," and -0.4 degrees in the group "grade III" (-28 degrees to 12 degrees). A mean (range) AT-angle of 4.8 (-4 degrees to 11 degrees) was measured in the pelvic limbs with rupture of the cranial cruciate ligament. Compared to literature that described AT-angles based on radiographs of normal limbs, reduced AT-angles were found in this study due to different lines of measurement of the femoral neck. This study documents that the AT-angle of the femoral neck does not influence patellar instability. This study also demonstrates that MR images can be used to make exact measurements of the canine AT-angle that represent the true anatomy of the femoral neck.  相似文献   
517.
518.
为进一步分析黑色素皮质激素受体-1(melanocortin-1 receptor,MC1R)基因的分子特性,利用生物信息学方法对GenBank中已报道的赤狐MC1R基因完整编码区序列的碱基组成特点及其编码蛋白的结构特征进行了预测及分析,构建了12个物种MC1R蛋白的系统进化树。结果表明,赤狐MC1R基因编码区序列长度为954 bp,共编码317个氨基酸,为单一外显子,G+C含量高于A+T,编码的蛋白质是一种分子质量为34.8694 ku,等电点为9.13的亲水性稳定碱性蛋白;存在7个强跨膜区、7个广泛磷酸化位点和1个潜在的蛋白激酶C磷酸化位点(第157位的苏氨酸),α-螺旋为其主要二级结构元件;属于G蛋白偶联受体家族一员,包括多个潜在重要功能基序;同源性分析与分子进化树结果均表明,赤狐与北极狐、狗和貉的亲缘关系最近。  相似文献   
519.
520.
梨(Pyrus spp)是深受国内外消费者喜爱的水果,果实香气是果实品质的重要指标,也是吸引消费者和增强市场竞争力的主要因素之一。本文以砂梨品种‘二十世纪’及其芽变品种‘金二十世纪’为试材,研究了其果实不同发育时期香气成分的差异,克隆获得了梨果实香气成分合成相关的醇酰基转移酶基因(PpAAT),分析了该基因在梨果实不同发育时期及不同部位中的时空表达规律,结果表明:‘二十世纪’绿熟期、商熟期和完熟期果实的主要香气成分均为己醛,‘金二十世纪’绿熟期果实的主要香气成分同样是己醛,但商熟期果实中己酸乙酯的含量迅速增加,成为主要香气成分,完熟期时含量进一步增加,高含量的酯类化合物可能是‘金二十世纪’具有浓郁香气的主要原因;随着果实的成熟,PpAAT基因在‘金二十世纪’果皮中的表达量呈逐渐下降的趋势,绿熟期表达量最高,商熟期表达量开始降低,完熟期表达量非常弱;PpAAT在果肉中的表达量呈先升高后降低的趋势,在商熟期果肉中表达量最高,绿熟期果肉中次之,完熟期果肉中的表达量最低。总体上,PpAAT基因在商熟期的表达量高于绿熟期和完熟期,在果皮中的表达量高于果肉。  相似文献   
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