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排序方式: 共有416条查询结果,搜索用时 17 毫秒
331.
Isabelle Pervieux Martin Bourassa Franoise Laurans Richard Hamelin Armand Sguin 《Physiological and Molecular Plant Pathology》2004,64(6):331-341
In this work, a cDNA encoding a defensin from Picea glauca, named PgD1, was isolated. The corresponding PgD1 cDNA encodes a putative protein of 83 amino acids with a calculated molecular mass of 8.9 kDa. The mature protein of 50 amino acids is characterized by the presence of specific highly conserved residues common to all plant defensins. PgD1 is developmentally expressed during seed germination and is also up-regulated by wounding and by jasmonic acid treatment, suggesting a role in both the constitutive and induced defense mechanisms. The recombinant protein was found to cause extensive growth inhibition of three fungal pathogens (Cylindrocladium floridanum, Fusarium oxysporum and Nectria galligena) at 2.5 μM. 相似文献
332.
Irene McNair Michelle Marshall Francis McNeilly Anette Botner Anne-Sofie Ladekjaer-Mikkelsen Isabelle Vincent Brigitte Herrmann Romeo Sanchez Carrie Rhodes 《Journal of veterinary diagnostic investigation》2004,16(2):164-166
A panel of 20 porcine sera was distributed to 5 laboratories across Europe and Canada. Each center was requested to test the sera for the presence of porcine circovirus type 2 antibodies using the routine assays, indirect immunofluorescence assay (IFA) and indirect immunoperoxidase monolayer assay (IPMA), and to determine the titer of each serum. Results from all centers were then compiled and correlated. They demonstrate a wide variation in the titers obtained between laboratories. These differences were dependent on the assay used and the choice of fixative. In general, IPMA gave higher titers than did IFA, and paraformaldehyde gave higher titers than did acetone or ethyl alcohol. This report highlights the need for standardized procedures and biologicals for this virus. 相似文献
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334.
The purpose of this study was to investigate the influence of different saline and colloid solutions on adrenal steroid secretion in dogs. Six healthy male Beagles underwent three infusion cycles: 10 min infusion of 30 ml/kg of NaCl 0.9%, 5 ml/kg of hydroxy ethyl starch, or 5 ml/kg of NaCl 10%. Plasma osmolality, hematocrit, total solids, cortisol and aldosterone levels were measured at 0, 5, 15, 30, 60, 120, 180 and 240 min after beginning infusion. Plasma ACTH levels were measured at 0, 15 and 240 min. An identical timing of sampling was applied during a control session omitting the fluid infusion. Osmolality, sodium, chloride and cortisol levels were found to be significantly higher with hypertonic saline solute compared to control. All fluid infusions lead to lowered plasma potassium, hematocrit, total solids and aldosterone values. ACTH concentrations did not show significant changes with any of the infusion cycles. The increase in cortisol levels suggests that hypertonic saline infusion could be interesting in critical care resuscitation, particularly in patients who are suffering from relative adrenal insufficiency. 相似文献
335.
Bourges-Abella N Raymond-Letron I Diquelou A Guillot E Regnier A Trumel C 《Veterinary ophthalmology》2007,10(1):12-18
OBJECTIVE: To describe the cells observed in conjunctival brush cytology (CBC) from normal horses and compare these findings with conjunctival structural histology so as to understand which cells are recovered from CBC. METHODS: This study was divided into three parts. (1) Conjunctival brush smears were collected from 20 healthy horses on both eyes and a differential count on 300 cells was carried out on May Grünwald-Giemsa (MGG) smears. (2) A similar protocol was used for whole eyes from five horses obtained rapidly after death from a slaughterhouse. The eyes were then assessed for conjunctival histology. (3) Cytobrush smears were collected from five healthy horses. Smears were examined after MGG or periodic acid Schiff (PAS) staining. RESULTS: The differential cell count showed a majority of deep and intermediate epithelial cells with very few superficial and goblet cells in both eyes. A stratified columnar to cuboidal epithelium was observed on nearly the whole surface of the conjunctiva. A stratified squamous type was observed at the palpebral and bulbar edges. Areas with highest mucus cell indices were found from the nasal to the temporal edge of the equine inferior conjunctiva in the upper palpebral segment near the fornix and in a part of the nasal fornix. In MGG smears no mucus cells were identified; however, they were numerous in PAS smears (22.6% +/- 11) and were mostly cylindrical cells (42.5% +/- 14.4 PAS positive). CONCLUSIONS: Cytobrush smears in the healthy horse are characterized by a majority of polyhedral and cylindrical cells and a few squamous cells. The cylindrical cells may be mucous cells and probably originate from the main stratified columnar to cuboidal epithelium. 相似文献
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337.
Thomas F Jamin E Wietzerbin K Guérin R Lees M Morvan E Billault I Derrien S Moreno Rojas JM Serra F Guillou C Aursand M McEvoy L Prael A Robins RJ 《Journal of agricultural and food chemistry》2008,56(3):989-997
Variability within the stable isotope ratios in various lipidic fractions and the fatty acid composition of muscle oil has been analyzed for a large sample (171 fish) of wild and farmed Atlantic salmon ( Salmo salar) from 32 origins within Europe, North America, and Tasmania. Sampling was extended over all seasons in 2 consecutive years and included fish raised by different practices, in order to maximize the range of variation present. It is shown that two readily measured parameters, delta 15N measured on choline and delta18 O measured on total oil, can be successfully used to discriminate between fish of authentic wild and farmed origin. However, the certainty of identification of mislabeling in market-derived fish is strengthened by including the percentage of linoleic acid C18:2n-6 in the lipidic fraction. Thus, several apparent misidentifications were found. The combination of these three analytical parameters and the size of the database generated makes the method practical for implementation in official laboratories as a tool of labeling verification. 相似文献
338.
The effect of textural modifications of solid milk gels on in vivo aroma release and aroma perception was investigated with a panel of 14 subjects. Great inter-individual differences were observed on aroma-release data, and the consequences of these differences on aroma perception were studied. From a hierarchical cluster analysis performed with several parameters extracted from release curves, the subjects were gathered into two groups, and a specific aroma-release profile was identified for each one. Then, by using a sensory profile, we showed that the intensity of the aroma perception was dependent on the release profile presented by the panelist. Second, we observed that, during the chewing phase, the aroma was perceived as more intense for the firmer gel and for panelists for whom the aroma release begins during the chewing of the product. 相似文献
339.
Kagan IA Coe BL Smith LL Huo CJ Dougherty CT Strickland JR 《Journal of agricultural and food chemistry》2008,56(14):5538-5543
Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter in animals that is also found in plants and has been associated with plant responses to stress. A simple and relatively rapid method of GABA separation and quantification was developed from a commercially available kit for serum amino acids (Phenomenex EZ:faast) and validated for tall fescue (Festuca arundinacea). Extraction in ethanol/water (80:20, v/v) at ambient temperature yielded detectable amounts of GABA. Clean separation from other amino acids in 28 min was achieved by gas chromatography (GC) with flame ionization detection (FID), using a 30 m, 5% phenyl/95% dimethylpolysiloxane column. The identity of the putative GABA peak was confirmed by GC with mass spectrometric (MS) detection. The relatively small effects of the sample matrix on GABA measurement were verified by demonstrating slope parallelism of GABA curves prepared in the presence and absence of fescue extracts. Limits of quantification and detection were 2.00 and 1.00 nmol/100 microL, respectively. Method recoveries at two different spike levels were 96.4 and 94.2%, with coefficients of variation of 7.3 and 7.2%, respectively. 相似文献
340.
Yan Boucher Maude Perrault-Hébert Richard Fournier Pierre Drapeau Isabelle Auger 《Landscape Ecology》2017,32(2):361-375