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排序方式: 共有166条查询结果,搜索用时 15 毫秒
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The goal of the present study was to characterize, by ribotyping and restriction endonuclease analysis (REA), 35 phocine Bordetella bronchiseptica isolates and to ascertain their relationship to one another and to isolates acquired from other host species. Thirty-four isolates were obtained in Scotland during a 10-year period encompassing the 1988 epizootic; the remaining isolate was obtained independently in Denmark. All phocine isolates had an identical Pvu II ribotype unique from the 18 ribotypes previously detected in strains from heterologous hosts. Alternative restriction enzymes, useful for subgrouping strains within Pvu II ribotypes, also failed to discriminate among isolates from seals. The exclusive occurrence of a single ribotype of B. bronchiseptica in a particular host species has not been previously observed. Similarly, REA based on either HinfI or Dde I profiles did not reveal detectable polymorphisms, although unique patterns were readily distinguished among a limited number of isolates from other host species. This is the first report demonstrating the utility of REA using frequently cutting enzymes for discrimination of B. bronchiseptica strains. These data suggest that B. bronchiseptica-induced respiratory disease in seals along the Scottish shore may be due to the circulation of a single, unique clone. 相似文献
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蘑菇废弃菌棒及其与猪粪混合发酵对沼气产量及质量的影响 总被引:1,自引:0,他引:1
为了研究厌氧消化过程中日产气量、累计产气量和甲烷含量随厌氧消化时间的变化规律,在中温35℃±1℃条件下,采用批式单相厌氧消化工艺,分别用香菇、杏鲍菇和平菇废弃菌棒与猪粪混合发酵。结果表明,蘑菇菌棒具有很好的产气潜力,其中香菇菌棒TS产气量最高,为142.9mL.g-1,平均产气量664.1mL.d-1,杏鲍菇菌棒所产气体甲烷含量最高,平均63.8%;添加猪粪调节蘑菇菌棒C/N至25/1,对香菇菌棒前期严重酸化现象起到了很好的缓冲作用,使香菇菌棒、杏鲍菇菌棒和平菇菌棒累计产气量较单一物料分别提高了131.5%、97.9%和79.9%。研究结论为:香菇、杏鲍菇和平菇废弃菌棒均具有良好的产气潜力;添加猪粪能显著提高蘑菇菌棒累计产气量,同时提高香菇菌棒甲烷含量,降低杏鲍菇菌棒甲烷含量,对平菇菌棒甲烷含量影响不大。 相似文献
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Maria Antonietta Brescia Giuliano Di Martino Clara Fares Natale Di Fonzo Cristiano Platani Stefano Ghelli Fabiano Reniero Antonio Sacco 《Cereal Chemistry》2002,79(2):238-242
Proton high‐resolution magic angle spinning nuclear magnetic resonance (1H HR‐MAS NMR) has been applied for the analysis of two cultivars of durum wheat produced in different Italian geographical areas. Furthermore, on the same samples, isotopic ratios were measured by mass spectrometry (IRMS). The application of chemometrics to these results permitted the discrimination of semolina by cultivar and geographical origin. A similar approach has been applied to the results obtained from chemical analyses. The comparison showed that NMR spectroscopy can provide a faster method for the detection of differences among the durum wheat semolina according to geographical and varietal origin. Furthermore, IRMS data are suitable to provide information about the geographical origin of samples. This present investigation is part of an extensive research project to find a scientific method capable of classifying wheat foods for the assignment of a “denomination of origin” trademark. 相似文献
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Identification and changes in the seasonal concentrations of heat shock proteins in roe deer (Capreolus capreolus) epididymides 下载免费PDF全文
AM Majewska W Kordan M Koziorowska‐Gilun P Wysocki 《Reproduction in domestic animals》2017,52(1):107-114
Heat shock proteins (HSPs) act as molecular chaperones with important regulatory functions. HSPs are considered to be essential factors in animal reproduction. In view of seasonal variations in the secretory activity of the reproductive tract of mature roe deer (Capreolus capreolus), the aims of this study were to identify HSPs in the epididymides and compare the expression of the identified proteins in three periods of the reproductive season. Two‐dimensional polyacrylamide gel electrophoresis revealed the highest number of polypeptides in homogenates of epididymal tissues and in caput, corpus and cauda epididymal fluids throughout the reproductive season. Epididymal tissue homogenates and epididymal fluids were analysed by tandem mass spectrometry (MS/MS) to reveal 31 polypeptides with enzymatic activity, including polypeptides with antioxidant properties, structural and cell signalling functions. Moreover, among the identified polypeptides, five of them were similar to heat shock proteins: endoplasmin (Grp94); heat shock protein 90 kDa (HSP90); 78‐kDa glucose‐regulated protein (Grp78); chain A, the crystal structure of the human HSP70 ATPase domain and heat shock protein beta‐1 isoform X. The concentrations of the analysed polypeptides, expressed in optical density units (ODU), differed significantly (p ≤ .05) across the examined periods of the reproductive season. The highest ODU values for almost all analysed proteins were observed during the rutting period. The presence of HSPs in the epididymal tissues and fluids of roe deer in different periods of the reproductive season could indicate that those proteins play an important role in sperm maturation in the epididymis. 相似文献
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The Usefulness of Captive Kept Capercaillie (Tetrao urogallus L.) as the Semen Donors for Artificial Insemination and Gene Pool Preservation In vitro 下载免费PDF全文
Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106 per ml to 3520 × 106 per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons. 相似文献