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SUMMARY Bronchoalveolar lavage (BAL) was performed at weekly intervals in 10 Thoroughbred horses in race training (group 1) and in 4 rested horses (group 2) for 10 weeks. Lavages were continued on a weekly basis in 4 group 1 horses for an additional 9 weeks (group 3). Cytological analysis of samples included leukocyte counts, erythrocyte counts, differential leukocyte counts, and haemosiderophage score. The mean leukocyte concentration was significantly lower in group 1(92.1 ± 4.6 cells/μL) when compared with group 2 (133.5 ± 8.2 cells/μL), P = 0.037. The differential leukocyte data were not significantly different between groups. There was a large amount of variability in the percent-age of macrophages and lymphocytes in the differential counts over time with no obvious trends. The proportion of neutrophils demonstrated a tendency to decrease over time for both groups 1 and 2. Erythrocyte counts and haemosiderin scores were significantly higher in the exercising group than the rested horses. Neither exercise nor the technique itself evoked an inflammatory response in the BAL fluid.  相似文献   
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本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化  相似文献   
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Abstract  The fish communities of all Austrian natural lakes ( n  = 43) larger than 50 ha in surface area were assessed and the historical fish communities in c . 1850 were reconstructed. During the last 150 years, the fish communities of Austrian lakes have altered: in 49% of lakes at least one indigenous fish species, usually sensitive or small-bodied taxa, is now missing. Conversely, in all but one of the 43 lakes the number of fish species has increased. In particular, certain fish species of interest to angling and commercial fisheries now occur in more lakes. Generalised linear models were used to identify variables that would explain the loss of fish species using categories of lake use (ranking score). The category human population density around the lakes seemed to be one of the main causes for the loss of fish species.  相似文献   
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Phosphorus (P) is necessary for growth and nitrogen fixation, and thus its deficiency is a major factor limiting legume production in most agricultural soils. The effect of phosphorus supply on nodule development and its role in soybeans (Glycine max L.) was studied in a nutrient solution. Plants were inoculated with Bradyrhizobium japonicum and grown for 35 days in a glasshouse at a day and night temperature of 25℃ and 15℃, respectively. Although increasing P supply increased the concentrations of P and N in the shoots and roots, the external P supply did not significantly affect the P concentration in the nodules, and the N fixed per unit nodule biomass decreased with increasing P supply. The nitrogen content in the shoots correlated well with the P content (r=0.92**). At an inoculation level of 10^2 cells mL^-1, the P supply did not affect the number of nodules; however, at inoculation levels of 10^3.5 and 10^5 cells mL^-1, increasing P supply increased both the number and size of nodules. Irrespective of the inoculation level, increasing P supply increased the nodule biomass relative to the biomass of the host plant. It is suggested that the P deficiency specifically inhibited the nodule development and thereby the total N2 fixation.  相似文献   
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Self-Assembled Smectic Phases in Rod-Coil Block Copolymers   总被引:1,自引:0,他引:1  
Rod-coil block copolymers are self-assembling polymers that combine the physics of orientational ordering of rodlike polymers and the microphase separation of coil-coil block copolymers. Several new solid-state morphologies were observed in a series of anionically synthesized model poly(hexyl isocyanate-b-styrene) rod-coil diblock copolymers examined by transmission electron microscopy and selected-area electron diffraction. The rod-coils formed smectic C-like and O-like morphologies with domain sizes ranging from tens of nanometers to almost 1 micrometer. Both structural and orientational changes were found for increasing rod volume fractions. In addition, some morphologies exhibited spontaneous long-range orientational order over many tens of micrometers.  相似文献   
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Processes of globalisation in the conventional food provision system have had widespread negative impacts on small‐scale farmers. Yet, alternative food networks, which are characterised by more sustainable production/consumption practices and fairer trade relations, have increasingly been ‘going global’ and, in the process, have been integrating small‐scale farms in the South. One such high‐value export‐led commodity is certified organic shrimp. International third‐party certification schemes are becoming popular as a tool to verify the intangible attributes of such commodities. Using concepts of multifunctionality and agrarian change, this paper examines the implications of introducing an international environmental certification programme to a site where the ‘peasantry’ has been preserved and has limited integration in the global agro‐food system. Drawing on a case study that examines the first certified organic shrimp production project in Vietnam, this paper concludes that the current movement towards post‐productivism in the global North has potential to keep local farming practices in the global South by justifying the value of peasant‐like production methods through international certification. As a result, the development path of agrarian transition might be reshaped into a form not necessarily pursuing industrialisation. This leads to the new interpretation of pre‐ and post‐productivism beyond the North and South divide.  相似文献   
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