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101.
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采用平板稀释法从西藏拉鲁湿地土壤中分离酵母菌,开展城市湿地酵母菌多样性研究。结合经典分类法及26S rDNA D1/D2区域序列分析,对获得的酵母菌菌株进行系统分类,并进行产胞外酶活性菌株的皿内初筛。结果显示,分离得到的83株酵母菌分属于隐球菌属Cryptococcus、假丝酵母属Candida、原囊菌属Protomyces、红酵母属Rhodotorula及孢囊线黑粉酵母Cystofilobasidium等5个属16个种,其中胶红酵母Rhodotorula mucilaginosa相对丰度最高,约26%,其次为维多利亚隐球酵母Cryptococcus victoriae和山杨隐球酵母Cryptococcus aspenensis;多样性分析表明,LhWS6样点的酵母菌多样性最丰富,LhWS9样点则最低;产胞外酶活性菌株初筛结果表明,25℃下产脂肪酶活性菌株比例最高,为67%,而4℃下产淀粉酶活性菌株数最多,为49株。另外,低温条件下产淀粉酶、果胶酶、纤维素酶和几丁质酶的活性菌株比例均高于常温条件。结果表明拉鲁湿地土壤酵母菌总体种类较丰富,但每个样点的种类相对单一,说明湿地生境或人为活动一定程度影响到该生态环境酵母菌的种群分布,开发青藏高原耐低温、产胞外酶等活性菌株具有一定的应用前景。 相似文献
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L.A. Zarazaga L. Todini P. Chemineau A. Locatelli 《Research in veterinary science》2010,88(2):233-238
Two experiments were designed to determine if melatonin concentrations differ between jugular veins. In a first experiment, blood was collected continuously every 30 min from each jugular during 12-h from 6 ewes. In a second experiment, 100 ewes were sampled twice at night simultaneously from the two jugular veins. In both experiments, mean melatonin concentrations were similar between right and left jugulars. However, within individuals, large differences were observed between the two sides (p < 0.001). This difference was stable over time and the higher side varies among individuals. The concentrations of prolactin and oxytocin, measured in the same samples did not show such differences. This observation raises the question of the origin of this phenomenon. Moreover, it has important implications for studies in which melatonin concentrations need to be assessed accurately. Indeed, a reliable quantitative assessment of melatonin production by the pineal gland requires sampling from both jugular veins. 相似文献
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液相色谱质谱联用分离、鉴定芥蓝中脱硫芥子油苷 总被引:6,自引:0,他引:6
从芥蓝菜薹中提取芥子油苷,经阴离子交换柱DEAE-Sephadex A-25纯化和硫酸酯酶脱硫,得到脱硫芥子油苷提取液.比较了两种高效液相色谱的流动相体系(甲醇与水体系和乙腈与水体系)及两种长度(250 mm×4.6 mm和150 mm×4.6 mm)的C18色谱柱(Prontosil ODS2,粒径5μm)对芥蓝脱硫芥子油苷的分离效果,确定分离条件为乙腈与水流动相体系和250 mm×4.6 mm C18柱.采用质谱联用及紫外扫描,在芥蓝菜薹中检测出7种脂肪族芥子油苷和4种吲哚族芥子油苷,其中4-甲硫基丁基芥子油苷为第一次在芥蓝中检测到.芥蓝中主要以脂肪族芥子油苷为主,占总芥子油苷含量的91.6%,而吲哚组芥子油苷的含量仅占8.4%.其中,3-丁烯基芥子油苷和4-甲基亚硫酰丁基芥子油苷为主要芥子油苷组分,分别占总含量的47.9%和35.5%,而含量最低的为4-羟基-3-吲哚甲基芥子油苷,只占总芥子油苷含量的0.2%. 相似文献
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ZHANG Zhi-fei LIANG Chun-nian GUO Xian WANG Hong-bo DING Xue-zhi WU Xiao-yun CHU Min PEI Jie LA Huan ZHANG Guo-mo YAN Ping 《中国畜牧兽医》2016,43(12):3257-3262
The blood physiological and biological indexes were determined in both polled and horned yaks, to investigate the differences of body condition and metabolism between the two breeds, and provide a comprehensive understanding for new yak breeds. Thirty physiological and biochemical indexes of the polled and horned yaks were measured, and all these data were analyzed by independent-samples t test to compare the same index between the two groups. The results showed that there were extremely significant differences (P<0.01) in 11 indexes,5 indexes reached significant differences (P<0.05) and no significant differences (P>0.05) in 14 indexes between the polled and horned yaks. The results suggested that the polled yak was easier to adapt to the plateau hypoxia and there were many differences in adaptability of plateau hypoxia, kidney metabolism, liver metabolism and the growth and development of the bone between the polled and horned yak. This study could provide scientific basis for better protection and utilization of yak and the selection of the new yak breeds. 相似文献
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Bacteroides nodosus involved in several outbreaks of ovine footrot over a number of years were subjected to DNA restriction endonuclease analysis. Individual isolates were found to have characteristic Bam HI profiles which permitted their accurate identification and differentiation from other isolates. Bam HI profiles of B. nodosus isolates were used in epidemiological investigations involving consecutive outbreaks of footrot on individual and neighbouring farms. The relationship of given isolates to a common source could be established by this means. Restriction endonuclease analysis provides an additional epidemiological tool in ovine footrot investigations as it accurately identifies interstrain differences in a manner not possible by conventional bacteriological and serological means. 相似文献
110.
采用盆栽试验,研究了脂肪族芥子油苷和吲哚族芥子油苷的合成前体甲硫氨酸和色氨酸单独及配合表面活性剂叶面喷施对芥蓝(Brassica alboglabra L.)生长及菜薹中芥子油苷组分和含量的影响。结果表明,各处理对芥蓝生长指标及芥子油苷组分无显著影响,在芥蓝菜薹中均检测到7种脂肪族芥子油苷和4种吲哚族芥子油苷。与喷施清水对照相比,甲硫氨酸、色氨酸单独叶面喷施及表面活性剂辅助的色氨酸叶面喷施,对芥蓝菜薹总芥子油苷含量、总脂肪族芥子油苷含量和总吲哚族芥子油苷含量均无显著影响。表面活性剂辅助下甲硫氨酸叶面喷施处理中菜薹总芥子油苷和总脂肪族芥子油苷含量比清水对照处理分别提高28.5%和31.9%,其中在11种芥子油苷中脂肪族芥子油苷3-丁烯基芥子油苷含量提高幅度最大,达到44.3%,同时表面活性剂辅助下甲硫氨酸叶面喷施显著提高了芥蓝菜薹全硫含量并降低了氮硫比(N/S)。本试验结果表明,有效供给甲硫氨酸能明显促进脂肪族芥子油苷的合成和积累,而辅之以表面活性剂能增进叶面对甲硫氨酸的吸收效果,其影响机理还有待进一步研究。 相似文献