Liquid chromatographic method for quantitative determination of free fatty acids in butter

A liquid chromatographic method has been developed for the determination of free fatty acids in butter. The fatty acids are converted to the p-bromophenacyl esters, via a crown ether-catalyzed reaction, without separation from the other butter components. The esters are separated on a C18-bonded silica column by using an acetonitrile-water solvent gradient and quantitated using the ester of heptadecanoic acid as internal standard. C16 and C18:1 co-elute in the acetonitrile-water system but are separated using an isocratic methanol-acetonitrile-water system. Limits of detection range from 7 ng for butyric acid to 45 ng for linoleic acid. The average coefficient of variation (n = 10) for 10 free fatty acids from a butter was 5.83%.     

黄土高原丘陵沟壑区土壤水资源平衡利用与生态植被可持续发展

黄土高原丘陵沟壑区林草植被建设对控制水土流失和农业可持续发展具有双重意义。但是,大量资 料表明,黄土高原丘陵沟壑区林地和草地土壤水分严重亏缺,林草植被对土壤水资源的过度利用必将产生严 重后果,笔者强调生态植被建设须坚持土壤水资源平衡利用原则。在对土壤水量收入和支出诸因素分析的基 础上,指出采取拦蓄降水、降水高效叠加利用、覆盖保墒和减少植被蒸腾等途径及措施,以实现土壤水资源平 衡利用。提出林地降水高效叠加利用技术的思路及研究解决办法;研究建立植物蒸腾耗水量评价指标体系, 为筛选节水植物种类或种提供科学依据;植被蒸腾量的调控,根据叶面积指数与土壤耗水量的关系,在土壤水 资源平衡利用的原则下,确定其盖度和种植密度,后期通过控制树冠、适度疏枝、合理平茬(刈割)等进一步加 以调节。     

A case-control study of pathogen and lifestyle risk factors for diarrhoea in dogs

Diarrhoea is a common and multi-factorial condition in dogs, the aetiology of which is often incompletely understood. A case-control study was carried out to compare the carriage of some common canine enteric pathogens (enteric coronavirus, parvovirus, distemper, endoparasites, Campylobacter and Salmonella spp.), as well as lifestyle factors such as vaccination history, diet and contact with other species, in dogs presenting at first opinion veterinary practices with and without diarrhoea. Multivariable conditional logistic regression showed that dogs in the study which scavenged or had had a recent change of diet (OR 3.5, p=0.002), had recently stayed in kennels (OR 9.5, p=0.01), or were fed a home-cooked diet (OR 4, p=0.002) were at a significantly greater risk of diarrhoea, whilst being female (OR 0.4, p=0.01), currently up to date with routine vaccinations (OR 0.4, p=0.05) and having contact with horse faeces (OR 0.4, p=0.06) were associated with a reduced risk. None of the pathogens tested for was a significant factor in the final multivariable model suggesting that in this predominantly vaccinated population, diarrhoea may be more associated with lifestyle risk factors than specific pathogens.     

A cross-sectional study of geriatric horses in the United Kingdom. Part 1: Demographics and management practices

Reasons for performing study: With growing numbers of aged horses, geriatric medicine is becoming increasingly important in equine veterinary practice; however, there is a paucity of information on the UK equine geriatric population. Objectives: To describe the demographic characteristics of the equine geriatric population and to assess management practices undertaken by owners of geriatric horses (aged ≥15 years). Methods: A cross‐sectional study was conducted, surveying a randomly selected sample of veterinary registered owners with horses aged ≥15 years, using a self‐administered postal questionnaire. Results: Horses aged ≥15 years represented 29% of the equine population in the study area. The response rate to the questionnaire survey was 80.2%. Management practices were similar to those previously described for the general equine population. However, the level of exercise and feeding practices changed significantly with increasing age. A summary of the demographic characteristics, feeding and management of horses in a sample of the geriatric equine population is presented. Conclusions and potential relevance: The management of geriatric horses has a direct effect on their health and welfare and this study has provided valuable information on the demographics and management of geriatric horses and ponies in the UK. The information can be used to form targeted owner education programmes for geriatric health and should aid in the investigation and prevention of disease.     

原发性肾病综合征并发急性肾功能衰竭的临床与病理分析

目的；观察原发性肾病综合征(iNS)并发急性肾功能衰竭(ARF)的临床与病理。方法：对42例iNS并发ARF患者临床和病理改变进行分析。结果：iNS并发ARF的发生率为5．87％，临床上以少尿型为主(78．6％)．起病均在iNS的急性期。42例患者临床表现为大量蛋白尿、高度水肿，病程中无明显诱因出现少尿，尿素氮与血清肌酐增高。肾脏病理检查肾小球以轻微改变为主，其中微小病变型16例．轻度系膜增生型肾炎2l例；肾小管间质的病变却表现为广泛肾间质水肿及小管上皮细胞灶性坏死。经利尿、强的松等治疗后，36例患者肾功能逐渐恢复正常。结论：iINS并发ARF多发生于肾小球轻微改变者；尽早明确iNS并发ARF，并给予适当治疗，绝大多数患者肾功能可以恢复。     

Vaccination against Schistosoma mansoni with purified surface antigens

Two surface antigens were isolated from young or adult schistosomes by affinity chromatography with monoclonal antibodies. Vaccination with an antigen having a molecular weight of 155,000 gave partial protection against challenge in some batches of mice and in a group of cynomolgus monkeys. Vaccination with an antigen having a molecular weight of 53,000 gave similar levels of protection in mice. The results demonstrate that protection can be obtained with single antigens, but the precise requirements for reproducible vaccination are as yet unknown.     

两种吡虫啉种衣剂在棉花和土壤中的残留动态研究

采用田间试验方法，研究了两种吡虫啉种衣剂在棉花和土壤中的残留消解动态，并对其在棉花上使用的安全性作出了评价。结果表明，两种吡虫啉种衣剂无论在棉株中或土壤中消解动态没有显著差异，其消解速度相当缓慢，有较长的药效。试验还表明，无论是推荐药量还是加倍药量．在正常使用条件下，都不会造成棉子残毒污染和土壤的残留积累。     

Simultaneous expression of globin genes for embryonic and adult hemoglobins during mammalian ontogeny

The dominant hemoglobin of the adult hamster was detected in yolk-sac erythroid cells, and its identity was confirmed by peptide mapping and by analysis of relevant peptides. Both the presence and active synthesis of two embryonic hemoglobins presumed to exist only in yolk-sac erythroid cells were detected in neonatal liver and spleen. Thus the time span of expression of both embryonic and adult globin genes during mammalian ontogeny may be considerably broader than presently believed.     

辅酶Q10污泥施用对作物和土壤效应的研究

为了探索辅酶Q10污泥施用对土壤和作物的影响,以玉米为供试作物,进行了不同用量污泥施用及与单施化肥对比的田间试验。结果表明,污泥施用增加了玉米的株高,400kg/667m2施肥量比空白区平均增加14cm,比单施化肥区平均增加6.5cm;400kg/667m2施肥量比空白区增产10%~15%,达到差异显著水平,与单施化肥区无显著差异;施用污泥与空白区相比,玉米籽粒蛋白质、脂肪和淀粉含量均有所提高,与单施化肥相比,污泥对提高籽粒蛋白质含量的作用更明显;污泥施用后对提高土壤中磷的作用最大,其次为氮,对有机质和钾的影响微乎其微,对土壤的p H值没有影响。辅酶Q10污泥施用对玉米生长、产量形成和品质均具有良好的效应,同时能够起到培肥土壤的作用。