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61.
In this study, we determined the occurrence of the tsh gene among 305 Escherichia coli isolates from chickens by means of the polymerase chain reaction and agglutination of chicken erythrocytes; 200 of those isolates were obtained from chickens with colisepticemia, 52 isolates were from lesions of cellulitis, and 53 were from feces of normal chickens. The tsh gene was found in 79 (39.5%) isolates from colisepticemia, in 10 (19%) cellulitis-derived E. coli isolates, and in two (3.8%) fecal isolates. Among the tsh+ strains, 68 (86%) isolates from colisepticemia and nine (90%) from cellulitis agglutinated chicken erythrocytes in the presence of mannose, after growing the strains on colonization factor antigen agar plates at 26 C, which confirms a correlation between mannose-resistant hemagglutination and expression of hemagglutinin Tsh. These results show, for the first time, the presence of the gene tsh in cellulitis-derived E. coli isolates; the high frequency of this gene among avian pathogenic E. coli isolates in Brazil indicates that its putative role as a virulence factor should be studied more thoroughly. 相似文献
62.
Karen M Vernau Anna Osofsky Richard A LeCouteur 《Veterinary Clinics of North America: Exotic Animal Practice》2007,10(3):731-58, v
Completion of a thorough neurological examination of a rabbit is essential for clinicians to determine the location of a neurological problem. Determination of the location of a lesion (whether solitary or multifocal/diffuse) enables a clinician to list the most likely causes of the problem. This article presents the neurological examination of the rabbit, followed by a practical guide to lesion localization in this species. 相似文献
63.
M Glade Weiser Linda M Vap Mary Anna Thrall 《Veterinary Clinics of North America: Small Animal Practice》2007,37(2):221-36, v
The typical technologies used in veterinary hematology and biochemical analyzers are reviewed, along with associated advantages and disadvantages. Guidelines for implementing a successful in-clinic laboratory are provided, including criteria for system evaluation and expectations for comparative performance evaluations. The more common problems and limitations associated with in-clinic laboratory diagnostics and how to best prevent them are also discussed. 相似文献
64.
Anna Johansson Jan-Kees C. Goud Christina Dixelius 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(2):139-149
Verticillium longisporum is a soil-borne fungal pathogen causing vascular wilt of Brassica crops. This study was conducted to enhance our knowledge on the host range of V. longisporum. Seven crop species (barley, oat, oilseed rape, pea, red clover, sugar beet and wheat) and five weed species (barren brome,
black-grass, charlock, cleavers and scentless mayweed) all common in southern Sweden were evaluated for infection by response
to V. longisporum. Oat, spring wheat, oilseed rape, scentless mayweed and charlock inoculated with V. longisporum in a greenhouse showed stunting to various degrees close to the fully ripe stage. Based on the extent of microsclerotia formation,
explants were separated into four groups: for pea and wheat, <5% of the samples had formed microsclerotia; for scentless mayweed,
5–10%; for oat, 10–20%; and for charlock and oilseed rape >80%. The results suggest that plant species outside the Brassicaceae can act as reservoirs of V. longisporum inoculum. Soil inoculum densities in nine fields were monitored over a period of 12 months, which ranged from 1 to 48 cfu
g−1 soil. Density of microsclerotia was lowest just after harvest, reaching its maximum six months later. No significant correlation
between inoculum density in soil and disease incidence on oilseed rape plants was found. However, the data suggest that a
threshold of 1 cfu g−1 soil is needed to cause disease on oilseed rape. Species identification based on microsclerotia morphology and PCR analysis
showed that V. longisporum dominated in soil of seven, and V. dahliae in two of the nine fields studied. 相似文献
65.
Jrme Van Biervliet DVM Dipl ACVIM Marc Kraus DVM Dipl ACVIM Brett Woodie DVM Dipl ACVS Thomas J. Divers DVM Dipl ACVIM Dipl ACVECC Anna Gelzer Dr. Med. Vet. Dipl ACVIM Dorothy Ainsworth DVM PhD Dipl ACVIM 《Journal of Veterinary Cardiology》2006,8(1):69-73
A 5-year-old Holstein cow, pregnant with a valuable calf, was presented with signs of heart failure (tachycardia, peripheral edema, and distended jugular veins) related to pericardial lymphoma and associated cardiac tamponade. In addition, pleural effusion was present in both hemithoraces. Medical treatment, which consisted of repeated pericardiocenteses, placement of indwelling pleural catheters, administration of intravenous fluid therapy, antibiotics and anti-inflammatory drugs, was ineffective in controlling recurrence of clinical signs despite a temporary improvement. A standing thoracoscopic pericardiotomy was performed in an attempt to reduce clinical signs of heart failure and to prolong life. Clinical signs of heart failure abated and no recurrence was seen. Standing thoracoscopic pericardiotomy along with possible corticosteroids can be recommended as palliative treatment in an effort to extend life for reproductive performance in genetically valuable animals. 相似文献
66.
67.
Urban dwellers experience conflicting thoughts and feelings about urban woodlands; valued for their natural qualities, the relief they provide from the stress of modern urban living and the opportunities they afford for children's play and exploration. At the same time the seclusion inherent in this type of urban greenspace seems fraught with risk from crime, vandalism and abuse. Whilst many of these characteristics are well-researched, less is known about the differing perceptions of particular social groups. This study aimed to explore the ways in which age affects urban dwellers’ aspirations, values and fears concerning the woods, and woodland accessibility, focusing on the views of elderly people (aged over 65). This pilot study was based in Norfolk Heritage Park, an urban park containing a variety of woodland settings located in Sheffield, UK. The questionnaire survey (participantsn=97) revealed that although walking is the most popular leisure activity, most respondents did not visit urban parks as often as they would like, regardless of age. Whilst many of the meanings associated with urban woodland (“relaxation”, “peacefulness”, “seasonal change”, “scenery” and “education”) were shared amongst age groups, it seemed that the elderly respondents particularly valued the woods for their links with the past, and opportunities for immersion in the natural world. Some respondents from all age groups had fears about their personal security in the woodland, and the concerns of the elderly were heightened by their perceived frailty, reduced mobility and sense of vulnerability; this age group had a corresponding need for particular measures to alleviate these problems. The study provides preliminary evidence for the idea that adults of different ages have differing perceptions and requirements in relation to urban woodlands. Due to the small sample size and other methodological issues, further research is needed to confirm and develop the findings. 相似文献
68.
Lia W. Liefting Anna C. Padovan Karen S. Gibb Ross E. Beever Mark T. Andersen Richard D. Newcomb David L. Beck Richard L.S. Forster 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(6):619-623
Sequence comparisons and phylogenetic analysis of the 16S rRNA genes and the 16S/23S spacer regions of the phytoplasmas associated with Australian grapevine yellows, papaya dieback and Phormium yellow leaf diseases revealed minimal nucleotide differences between them resulting in the formation of a monophyletic group. Therefore, along with Australian grapevine yellows, the phytoplasmas associated with Phormium yellow leaf and papaya dieback should also be considered as Candidatus Phytoplasma australiense. 相似文献
69.
Anna German 《Phytoparasitica》1985,13(3-4):209-213
A 5-minute contact of nursing mothers of the Levant vole,Microtus guentheri, with paper impregnated with a DES suspension in soybean oil (125 μg/cm2 ) caused sterilization of 60% of the newborn female offspring. A 1-hour contact was sufficient to sterilize more than 90% of them. When the DES concentration was decreased to 1 μg/cm2 only 44% of the newborn female offspring were sterile although their nursing mothers had been exposed to contact with the treated paper for a period of 2 hours. The concentration of 0.1 μg/cm2 was totally ineffective in causing sterilization. Treatment of nesting material with DES offers a promising means of reproductive suppression in Levant voles. 相似文献
70.
Anna B. Marin Ann E. Colonna Koei Kudo Eugene M. Kupferman James P. Mattheis 《Postharvest Biology and Technology》2009,51(1):73-79
Post-harvest apple treatment with 1-methylcyclopropene (1-MCP) was previously found to inhibit fruit ripening but also to inhibit the production of volatile compounds that contribute to apple flavor. The first objective of this study was to determine if consumers could distinguish 1-MCP treated and untreated Gala apples [Malus sylvestris L. (Mill.) var. domestica Borkh. Mansf.] following long-term storage. Chemical analysis showed 1-MCP treated fruit had reduced flavor volatiles compared to untreated fruit. Consumer difference tests showed they could distinguish between 1-MCP treated and untreated fruit. A second objective was to compare consumers’ acceptance for 1-MCP treated to untreated apples. Both 1-MCP treated and untreated apples received high overall liking scores that were not significantly different. Equal numbers of consumers indicated preference for 1-MCP treated and untreated fruit and there was no difference in purchase intent. However, subsets of consumers who eat Gala, Fuji or Red Delicious apples showed preference for untreated over 1-MCP treated fruit compared to consumers who do not eat these varieties. 相似文献