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161.
162.
Aims: This study was conducted to clarify the taxonomic status of Francisella sp. strain Ehime‐1, a fish pathogen, in relation to the fish pathogens F. piscicida and F. philomiragia subsp. noatunensis and to F. philomiragia subsp. philomiragia. Methods and Results: Francisella sp. Ehime‐1 was compared to F. piscicida, F. philomiragia subsp. noatunensis and several F. philomiragia subsp. philomiragia isolates through sequencing of the 16S rRNA‐gene and several house‐keeping genes and determination of biochemical and phenotypic properties. Results show that F. piscicida is indistinguishable from F. philomiragia subsp. noatunensis by sequence and phenotypic traits. Francisella sp. Ehime‐1 and F. philomiragia subsp. noatunensis are clearly separated from F. philomiragia. Francisella sp. Ehime‐1 is biochemically, phenotypically and genetically different from F. philomiragia subsp. noatunensis (=F. piscicida), but DNA–DNA hybridization does not clearly support establishment as a separate species (level of relatedness 64% and 73·4%, mean 68·7%). Conclusions: We propose to elevate F. philomiragia subsp. noatunensis to species rank as F. noatunensis comb. nov., while F. piscicida is considered a heterotypic synonym of F. noatunensis comb. nov. Evidence suggests that Francisella sp. Ehime‐1 represents a novel subspecies of F. noatunensis, for which the name F. noatunensis subsp. orientalis subsp. nov. is proposed (=DSM21254T, = LMG24544T). Significance and Impact of the Study: This study contributes to the taxonomy and characteristics of fish‐pathogenic Francisella spp.  相似文献   
163.
Climatic change often affects life history aspects of aquatic insects. Long‐term monitoring was conducted to understand the life history variability of the riverine mayfly Ephemera orientalis in the Han river, where habitat is largely disturbed by summer floods. Water level of the study site, Godeok‐dong area in Seoul, is regulated by the Paldang Dam located approximately 14 km above the study site. E. orientalis often emerged in large numbers around the study area. Larvae were sampled monthly from April 2006 to July 2010 using a Surber sampler (50 × 50 cm, mesh 0.25 mm, two replicates). Additional qualitative sampling was conducted using a hand net. As a result, based on the larval body size distribution, E. orientalis had a univoltine life cycle with two distinct slow growing cohort groups: the S1group emerged during May–June and the S2 group emerged during August–September. Our previous study conducted in Gapyeong stream in Gyeonggi‐do showed that E. orientalis normally had three cohort groups, S‐1 and S‐2 groups and the F‐group (a fast growing cohort developed during May–August). However, the Han River population of E. orientalis lacked such a fast growing cohort. It is most probable that habitat disturbances caused by high water level during the rainy season negatively affected the development of the fast growing cohort (F‐group) in the Han River area. The relationships between monthly E. orientalis population data and water level in the Han River are presented.  相似文献   
164.
Captive environments often fail to resemble the wild environment in respects of limited space,unchanging habitat,lack of stimulus and contingency. Common animal welfare problems which occur in captive animals include low behavioral diversity,abnormal behavior and excessive inactivity. Environmental enrichment,as an effective strategy to tackle these problems and promote mental health of captive animals,has been recognized as an important principal for captive animal management. Among all the enrichment techniques,olfactory enrichment is a simple and effective method for improving the well-being of the olfactory sensitive felids. Behavioral problems were observed in six Amur leopards Panthera pardus orientalis at Beijing Zoological Garden.These were held in the older type exhibits which have now been rebuilt. These behaviors include stereotypic behavior and excessive inactivity caused by the spatially limited enclosures with low levels of stimuli. To determine the effects of predator,prey,and herb odors as potential enrichment materials for captive leopards,we conducted olfactory enrichment experiments for the leopards and tested the effects of nutmeg Myristica fragrans,feces of roe deer Capreolus capreolus and urine of Amur tiger Panthera tigrisaltaica to test for an increase in behavioral repertoire and activity. Odors provided in this study were also believed to improve the psychological and physiological health of individuals. To standardize the method of presentation the odors were introduced to the enclosures by rubbing or spraying onto a clean towel. Our results show that the selected three odors effectively increased the behavioral diversity. Ten new behavior types were observed in the nutmeg experiment,eight in the feces of roe deer experiment and six in the tiger urine experiment. Among the three odors,cats responded to nutmeg for the longest duration,followed by tiger urine and feces of roe deer. Leopards showed more play behavior in presence of nutmeg while more investigatory behavior in presences of feces of roe deer and tiger urine. Providing novel odors increased the spatial use of the exhibit and the animal' s increased use of the logs,sleeping platforms and bars in the cages. Novel odors also significantly increased the overall activity of the leopards,but the effects were diminished in about three hours.  相似文献   
165.
研究了喀斯特乡土树种伊桐的果实性状、种子性状、播种萌发和幼苗生长等的基本特征。结果表明:伊桐果实单果鲜重63.20~149.50g,其长度和宽度则分别为55.59~86.60mm和38.59~51.80mm,单果出种量19.95~57.15g,出籽率31.57%~40.81%,单果种子数343~690粒,单粒种子均重0.0582~0.0857g,其出籽率、单果种子数和单粒种子均重与果实重量存在一定程度的正相关;伊桐种子的长、宽平均分别为(25.93±2.80)mm和(13.72±2.88)mm,完整种子平均风干重(0.0153±0.0033)g,脱翅种子平均重(0.0112±0.0024)g,种翅占整个种子的(26.56±4.53)%;伊桐种子播前采取不同处理方式的平均发芽天数、平均发芽指数和平均发芽率等存在一定或是比较明显的差异,浸种、脱翅或两者相结合的方式均能有效缩短种子发芽时间并明显提高种子发芽率;伊桐幼苗的株高和基径的月均生长量分别介于3.3~16.3cm和0.32~2.80mm之间,其中经浸种处理的前期生长较快,未经浸种处理的中期生长较快。  相似文献   
166.
古侧柏种子活力与树龄的关系研究   总被引:1,自引:0,他引:1  
以陕西黄帝陵、河南嵩阳书院、山东岱庙、山西晋祠、北京中山公园、北京卧佛寺不同树龄侧柏(20~3 000年)种子为试材,测定其千粒重、发芽指数、活性氧(ROS)、丙二醛(MDA)、ROS清除酶(SOD、POD、CAT、GR、APX)活性,分析各指标与树龄的变化关系,探讨通过古侧柏种子活力判断古树衰老程度的可能性。结果表明:所选6个地点侧柏种子千粒重和树龄无相关关系;6个地点20年侧柏种子的发芽率和各ROS清除酶活性均高于其他树龄侧柏种子,古侧柏种子ROS和MDA含量并没有随树龄增加而增大;6个地点侧柏种子发芽指数、ROS(O2.-、H2O2、.OH)、MDA、各ROS清除酶活性与树龄无显著相关关系;3 000年古侧柏与20年侧柏相比,种子发芽指数和ROS清除酶活性仍较高,而ROS和MDA含量相对较低。可见,高龄古侧柏的种子生理机能没有明显衰退迹象。  相似文献   
167.
In the present study, bee colonies were smoked with tobacco smoke in order to evaluate the monthly changes in the numbers of worker bees, the infestation rates of worker bees and queens with bee lice, and the annual average honey production per colony. In July of each year, 12 colonies were smoked with tobacco smoke; the remaining hives not smoked with tobacco smoke served as the control. The results indicated that the applications of tobacco smoke during July gave rise to an impressive reduction in the Braula infestation rate on workers (below 1.8%) and reduced the amount of bee lice on the queen to zero throughout the 2–3 months following smoke treatment. In the colonies not treated with smoke, the Braula infestation rates on worker bees started to increase in May and continued to increase constantly during the rest of year, reaching maximum infestation rates of 28.2% and 33.8% in December, with an average of 15 and 17 lice per queen in November in the first and second years, respectively. Worker bee populations peaked in April and July of each year in both treatments. The average honey production per colony was significantly higher in the colonies treated with smoke than those that were not for the first and second years. In conclusion, early summer months may be the crucial time to smoke the colonies with tobacco smoke in order to keep bee lice at low levels for the remaining seasons.  相似文献   
168.
不同风信子品种在南京地区的物候期及生长特性分析   总被引:1,自引:0,他引:1  
对从荷兰引进的17个风信子(Hyacinthus orientalis L. )品种在南京地区的物候期、观赏特性和生长状况进行了调查分析.调查结果表明,17个风信子品种的耐寒性较强,出苗期最早在1月下旬,多数品种的出苗期在2月中下旬;绝大多数风信子品种的叶片展开期集中在3月14日至20日;花现色期多为2月底至3月初,第1朵花的开花期在3月中上旬;大部分品种的单花序开花持续时间和群体开花持续时间较长,分别达20~22 d和27~31 d.17个风信子品种的花均具有非常浓烈的香味,花蕾与花脉颜色相同,花色从花脉辐射至花瓣边缘并逐渐变淡,花色艳丽, 观赏性强. 少数品种具1个花枝, 多数品种具2个花枝, 花茎长度12.7~21.9 cm, 多数品种的花茎长度在17 cm以上;主花序长度多在11 cm以上,约占整个花茎长度的2/3;单花序花朵数为20~61.各品种的花瓣数和花药数基本一致,多以6为基数;17个风信子品种的花粉均有一定的萌发能力,其中9个品种的花粉萌发率较高,均超过40%.多数品种的叶片数为6或7,叶片长18~29 cm,宽2.2~3.6 cm.除品种'阿姆斯特丹'、'简波斯'和'福特'外,其余品种均可以分生出籽球,其中,品种'蓝星'、'蓝夹克'和'爱丽斯'的籽球分生能力最强,分生率达66%以上;不同风信子品种的籽球直径也各不相同,多数籽球直径较大,为3~5 cm.结果显示,风信子可作为早春花卉在南京进行种植,但具体种植条件尚待深入研究.  相似文献   
169.
AIMS: The present work aimed at isolating antibacterial constituents from the whole plant of Artemisia princeps var. orientalis active towards nine human intestinal bacteria. METHODS AND RESULTS: The growth-inhibiting activities of materials derived from the Artemisia whole plant towards test bacteria were examined using an impregnated paper disc method. The biologically active constituents of the Artemisia whole plant were characterized as the sesquiterpene lactones seco-tanapartholides A and B by spectroscopic analysis. In a test using 1 mg per disc, seco-tanapartholides A and B produced a clear inhibitory effect against Clostridium perfringens, Bacteroides fragilis and Staphylococcus aureus. These compounds did not affect the growth of test lactic acid-producing bacteria (Bifidobacterium adolescentis, Bif. breve, Lactobacillus acidophilus and Lact. casei) and Escherichia coli, whereas weak growth inhibition towards Bif. bifidum was observed. At 0.5 mg per disc, seco-tanapartholides A and B exhibited moderate growth inhibition towards Cl. perfringens but weak growth inhibition towards Bact. fragilis and Staph. aureus. CONCLUSIONS: Inhibitory action of seco-tanapartholides A and B towards specific bacteria without any adverse effects on lactic acid-producing bacteria may be an indication of at least one of the pharmacological actions of A. princeps var. orientalis whole plant. SIGNIFICANCE AND IMPACT OF THE STUDY: These naturally occurring Artemisia whole plant-derived materials could be useful as a new preventive agent against various diseases caused by harmful intestinal bacteria such as clostridia.  相似文献   
170.
The threo and erythro forms of guaiacylglycerol-7'-O-methyl 8'-vanillic acid ethers, threo and erythro guaiacylglycerol 8'-vanillin ethers, and threo guaiacylglycerol 8'-(4-hydroxymethyl-2-methoxyphenyl) ether have been isolated from fruits of Boreava orientalis. Structural determinations were made on the basis of UV, MS, 1H- and 13C-NMR spectral data, including two-dimensional shift correlation. The relative configurations were assigned on the basis of 1H-NMR chemical shifts.  相似文献   
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