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171.
Qi SS Wang WH Gao Q Xu XH He WH Zhaxi YP Tai LF 《Tropical animal health and production》2011,43(6):1219-1223
The distribution, size, and appearance of Peyer's patches vary according to species. In order to determine the anatomical
characteristics of Peyer's patches in small intestine of Bactrian camel, and age-related changes in the number of Peyer's
patches, 40 Bactrian camels of the following four age groups were studied: young (0.5–2 years), pubertal (3–5 years), middle-aged
(6–16 years), and old (17–20 years). The exact number of Peyer's patches was recorded, and the appearance of Peyer's patches
was described in detail. The results indicated that Peyer's patches of Bactrian camels not only have a particular anatomical
location and distinct appearance but also change with age. They were distributed in the whole small intestine and there were
four distinct types of Peyer's patches: nodular, faviform, cup-shaped, and cystic form Peyer's patches. However, the nodular
and cystic form Peyer’s patches are specific to Bactrian camel, which have not been found in other animals including Dromedary
camel. In addition, the distribution density of Peyer's patches in ileum was the maximum, then was jejunum and duodenum. Further
statistical analysis showed that the number of Peyer's patches was altered with age. The number peaked in 5-year-old camels
and declined subsequently with age. However, there was little change in the size of Peyer's patches in different age groups;
no age-related macroscopic variations in the shape or size of the Peyer's patches were found. Results obtained from this study
provide the basic information to further study on the gastrointestinal mucosal immunity of Bactrian camel. 相似文献
172.
大气氮沉降的不断加剧,改变了土壤理化性质,直接影响植物的生长与发育,间接影响了陆地生态系统碳库,进而可能改变全球气候变化进程。森林是陆地生态系统的主体,因此,弄清氮沉降如何影响森林生态系统碳库,对预测全球气候变化具有重要意义。笔者旨在详细分析氮沉降对森林生态系统土壤碳库输入和输出的影响,阐述氮沉降对森林生态系统凋落物分解、细根周转和土壤呼吸的影响研究进展和作用机制。截至目前,关于氮沉降对于陆地生态系统的影响研究报道较多,且国内外诸多学者也在森林生态系统土壤碳库对氮沉降的响应领域开展了较多试验研究,但多集中于碳输入和输出的总量分析,而对输入和输出各个组分的研究相对较少。笔者综述了国内外有关森林生态系统碳库输入和输出各组分对氮沉降响应的相关研究,为进一步揭示其响应机制和途径提供参考依据。 相似文献
173.
Danyi S Widart J Douny C Dang PK Baiwir D Wang N Tu HT Tung VT Phuong NT Kestemont P Scippo ML 《Journal of veterinary pharmacology and therapeutics》2011,34(2):142-152
Determination and kinetics of enrofloxacin and ciprofloxacin in Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a liquid chromatography/mass spectrometry method. J. vet. Pharmacol. Therap. 34, 142-152. The fluoroquinolones enrofloxacin (EF) and ciprofloxacin (CF) residues were investigated in the edible tissues of two important Asian aquacultured species such as Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry method. Fish and prawn were treated with medicated feed with multiple doses of EF, in field conditions. A validation study of the analytical method was realized in terms of linearity, specificity, precision (repeatability and within-laboratory reproducibility), recovery and decision limit (CCα). The time needed before the antibiotic disappears from animal tissues or reach the maximum residue limit (MRL, 100μg/kg) was assessed. The concentration values of EF detected in Tra catfish tissue were between the MRL and 2×MRL concentrations, according to the fish density, 7days following the end of the enrofloxacin treatment (20mg/kg body weight per day, for seven consecutive days). The concentration value of ER in prawn tissue was lower than the MRL and the limit of quantification (LOQ, 14μg/kg) 5 and 7days after the stop of the EF treatment (50mg/kg body weight per day, for five consecutive days), respectively. The mean detected levels of CF was much lower in comparison with that of EF, indicating that only a small part of EF is metabolized into CF (<5%) in both Tra catfish and prawn. 相似文献
174.
175.
176.
利用超声波提取和气质联用分析法,对散尾葵的提取物进行了组分和含量分析。结果表明,提取物含酸类化合物2种,占提取物总量的1.20%;醇类化合物3种,占提取物总含量 1.78%;酯类化合物5种,占提取物总量的7.11%;烷类化合物5种,占提取物总量的13.27%;醚类化合物2种,占提取物总含量 3.36%;酮类化合物1种,占提取物总含量 0.41% 。利用散尾葵提取物对10种居室空气中收集的细菌进行了抑菌性测定,对其中7种具有抑菌活性,而对放线菌、动性球菌、冷杆菌无抑制作用。对葡萄球菌和枯草芽孢杆菌抑菌力最强,125mg/mL浓度提取液抑菌率达到100%。 相似文献
177.
178.
179.
红池坝人工草地放牧方式和放牧强度的研究 总被引:5,自引:0,他引:5
在红池坝人工草地对放牧方式和放牧强度进行比较研究,同时对已给定的载畜量加以验证,以便制定该草地的最适放牧制度。研究结果表明,适于该地区的放牧管理制度是划区轮牧;各个阶段的载畜量与牧草生长速度之间的关系可用数学模型表示为:Y=179.5+5.48X,在每公顷7.5个绵羊单位的载畜量下进行中度放牧强度可获得草地最大产草量,并保持其稳定。 相似文献
180.
LFA—3和IL—2对机体免疫增强作用 总被引:1,自引:0,他引:1
以绵羊红细胞膜提取的LFA-3和猪外周血单个核细胞所产生的IL-2,同时或分别与新城疫Ⅳ系疫苗胸肌注射22日龄雏鸡,测定鸡体HI抗体效阶及Etg花环形成率的变化,结果表明,LFA-3组抗体效价与对照组差异极显著,IL-2也可显著提高IV系苗免疫后HI抗体效价,且两者的作用具有剂量依赖性。 相似文献