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41.
横断山北部是我国地理环境独特和生物多样性最丰富的地区之一,其生态恢复与重建对整个长江流域的水土流失治理及生态安全具有重要的现实意义,故一直受到国内外学术界的高度关注。但由于近40年来人类活动和气候环境的变化,其林木蓄积量大幅度减少,水土流失日趋严重,生态环境破碎化,部分野生动植物资源已濒临灭绝,已有研究表明属生态脆弱区。尽管该区实施退耕还林工程和天然林保护工程已四年,但因该区域有关生态环境(包括土壤钾素养分等)的基础研究资料较少,生态重建进度仍很缓慢。 相似文献
42.
为提高糙薏米中γ-氨基丁酸的富集量,采用响应面试验法对糙薏米的培养液组分进行工艺优化。结果表明:培养液中Na2SeO3浓度以10mg/L为宜,其发芽率最高,达(90.33±1.73)%;在Na2SeO3浓度为10mg/L的培养液中辅以11mmol/L CaCl2、87.7μmol/L GA3和31.5mmol/L MSG进行萌芽处理时,萌芽糙薏米中总硒、有机硒和GABA含量分别达0.42mg/100g、0.37mg/100g和116.69mg/100g,是一种具高值化产品开发潜力的保健食品基料。 相似文献
43.
利用超声波辅助水提取技术,以腌制佛手果为原料,考察提取时间、超声时间、提取温度、料液比对佛手果低聚糖提取得率的影响,采用正交试验对佛手果低聚糖的提取工艺进行优化,从单因素试验、正交试验结果以及节约能源角度,得出最佳工艺条件为:提取时间2 h,超声时间20 min,提取温度80℃,料液比1∶8,在此条件下,佛手果低聚糖得率为5.99(±0.15)%。采用体外结合胆酸盐实验评价佛手果低聚糖的降血脂功能,结果显示,佛手果低聚糖对胆酸钠(SC)、牛磺胆酸钠(STC)的吸附能力较强,其结合量分别为20.30(±0.39)、19.61(±0.71)μmol/mg,对甘氨胆酸钠(SGC)吸附能力较弱,其结合量只为14.38(±2.23)μmol/mg,提示佛手果低聚糖可能具有一定的降血脂功能。 相似文献
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Ortuño A Castellà J Criado-Fornelio A Buling A Barba-Carretero JC 《Veterinary journal (London, England : 1997)》2008,177(1):134-135
Within the framework of a local animal health programme, the presence of ectoparasites and haemoparasites was investigated in a colony of 25 cats in Barcelona. Diagnosis was performed both by standard parasitological procedures and molecular techniques. All cats were negative to haematozoan infection by microscopic examination of blood smears. However, Hepatozoon spp. was found in four cats as shown by amplification and sequencing of the 18S rRNA gene. Cat isolates were 100% identical to the isolate Hepatozoon spp. (Spain 2) from Southern Spain. This is the first time that Hepatozoon spp. has been identified in cats from Northern Spain. 相似文献
46.
The medical records of 468 horses that underwent 490 exploratory laparotomies for the correction of gastrointestinal diseases were reviewed to search for differences between Andalusian horses and other breeds. The seasonal distribution of surgical colics and their outcome and complications were also investigated. Bivariant analysis was used to compare the horses' age, gender and breed with the type of surgery, the bowel affected and the type of colic, and all these variables were compared in relation to euthanasia during surgery, complications, short-term survival and seasonal distribution. A total of 405 horses survived the surgery and 329 were discharged from the hospital. Horses less than one year old had better short-term survival than older horses. Andalusian horses suffered more inguinal hernias than the other breeds and were more prone to suffer laminitis as a complication. Colic surgery and inguinal hernias were also more common in the summer. 相似文献
47.
Martínez RA García D Gallego JL Onofre G Pérez J Cañón J 《Journal of animal science》2008,86(3):545-552
The genetic structure of 4 Colombian Creole cattle breeds, namely, Coste?o con Cuernos, Blanco Orejinegro (BON), Romosinuano (ROMO), and Sanmartinero (SM), was studied with an analysis of the available pedigree data. The comparison between the effective number of founders (f(e)) and the effective number of ancestors (f(a)) revealed a decrease in the genetic variation that was rather important for the ROMO and San Martinero breeds, which had the lowest f(a)/f(e) ratios (0.34 and 0.53, respectively). All breeds showed similar values for the number of equivalent generations traced, ranging from 3.1 in BON to 4.8 in ROMO. These 2 populations also had the lowest and the highest population sizes, respectively. The lowest average inbreeding coefficient considering the whole pedigree was obtained by BON (0.18%), whereas the highest was attained by ROMO (1.22%). Finally, the percentage of individuals with an inbreeding level greater than 6.25% in the reference population was high, indicating that the existing conservation management strategies could be improved to successfully maintain the genetic variability of these populations. 相似文献
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49.
González Canga A Sahagún Prieto AM José Diez Liébana M Martínez NF Vega MS Vieitez JJ 《Veterinary journal (London, England : 1997)》2009,179(1):25-37
The pharmacokinetic properties of drugs are closely related to their pharmacological efficacy. The kinetics of ivermectin are characterised, in general terms, by a slow absorption process, a broad distribution in the organism, low metabolism, and slow excretion. The kinetics vary according to the route of administration, formulation, animal species, body condition, age, and physiological status, all of which contribute to differences in drug efficacy. Characterisation of ivermectin kinetics can be used to predict and optimise the value of the parasiticide effects and to design programmes for parasite control. This article reviews the pharmacokinetics of ivermectin in several domestic animal species. 相似文献
50.