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排序方式: 共有556条查询结果,搜索用时 187 毫秒
141.
Burger DM Wiestner T Montavon PM Kündig H Hubler M Binder H Arnold S 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(2):85-96
The suitability of passive telemetry for long-term measurements of gastric motility in two groups of dogs with different body weights, four Beagles and four Labrador Retrievers, was investigated. An intra-abdominal measuring device, with a pressure sensor and electrodes within the gastric wall, allowed the continuous recording of the intensity and frequency of contractions simultaneously with an electromyogram (EMG). In fasting dogs a typical inter-digestive motility cycle was reproducible. Within 15 min of feeding the integral of the pressure curve increased significantly, reaching its maximum 30-45 min post-prandially. The peak frequency also significantly increased immediately after feeding, reaching the maximum of 22 contractions per 5 min. The post-prandial motility patterns of the groups were significantly different. The pressure amplitudes of the Labradors were significantly higher and the peak frequencies significantly lower than the Beagles. The addition of guar to the food (2.5% or 5%) leads to a significant reduction of the intensity of the antral contractions, whereas the frequency was hardly affected. In comparison, the effect of cellulose, as a food additive (2.5% or 5%), was rather modest. The intensity of the post-prandial contractions, influenced by cellulose, was significantly increased in Beagles, but was decreased in Labradors. Passive telemetry has been proven to be a suitable method for the long-term investigation of the physiological gastric motility and the effect of food additives. The measuring device was still functional after removal 8 weeks later. 相似文献
142.
Arnold CE Bordin A Lawhon SD Libal MC Bernstein LR Cohen ND 《Veterinary microbiology》2012,155(2-4):389-394
Gallium is a trivalent semi-metallic element that has shown antimicrobial activity against several important human pathogens. This antimicrobial activity is likely related to its substitution in important iron-dependent pathways of bacteria. The genus Staphylococcus, which includes human and animal pathogens that cause significant morbidity and mortality, requires iron for growth and colonization. In this study, gallium maltolate, at various concentrations between 50 and 200μM, inhibited the in vitro growth of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) at time-points between 8 and 36h after inoculation. The inhibitory activity of gallium maltolate against clinical isolates of MRSA and methicillin-resistant Staphylococcus pseudintermedius (MRSP) from a veterinary teaching hospital was determined. 相似文献
143.
144.
Stief B Möbius P Türk H Hörügel U Arnold C Pöhle D 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(1-2):38-44
Paratuberculosis is mainly an infectious disease of ruminants with worldwide distribution. Infection occurs in early stages of life. Other animal species beyond ruminants are rarely affected, however, experimental and natural infections are possible. A case of paratuberculosis in a miniature donkey (Equus asinus f. asinus) with typical clinical and pathomorphological changes is reported here. Lesions were mainly observed in the intestine. Causative for the profuse diarrhoea with emaciation was massive diffuse granulomatous enteritis involving large quantities of acid-fast organism mainly in macrophages. Granulomatous inflammation with acid-fast bacilli again in macrophages to a lesser degree could be detected in the liver. Mycobacterium avium subsp. paratuberculosis (MAP) was isolated from intestinal contents after an incubation period of four weeks. MAP-specific DNA (IS900 and f57) was detected by polymerase chain reaction in culture material. Additionally MAP-isolates were characterized by multi-target genotyping (MIRU-VNTR- and MLSSR-typing). Isolates belonged to the Type II group and exhibited a unique genotype different from other MAP strains in Germany. The donkey originated from a donkey breeding farm in France with intensive free ranging cattle in the neighbourhood and could have been infected there. Donkeys should be considered as paratuberculosis-susceptible animals in exceptional cases and as possible reservoirs or disseminators of infection. 相似文献
145.
Stabej P Leegwater PA Stokhof AA Domanjko-Petric A van Oost BA 《American journal of veterinary research》2005,66(3):432-436
OBJECTIVE: To evaluate the role of the phospholamban gene in purebred large-breed dogs with dilated cardiomyopathy (DCM). ANIMALS: 6 dogs with DCM, including 2 Doberman Pinschers, 2 Newfoundlands, and 2 Great Danes. PROCEDURE: All dogs had clinical signs of congestive heart failure, and a diagnosis of DCM was made on the basis of echocardiographic findings. Blood samples were collected from each dog, and genomic DNA was isolated by a salt extraction method. Specific oligonucleotides were designed to amplify the promoter, exon 1, the 5'-part of exon 2 including the complete coding region, and part of intron 1 of the canine phospholamban gene via polymerase chain reaction procedures. These regions were screened for mutations in DNA obtained from the 6 dogs with DCM. RESULTS: No mutations were identified in the promoter, 5' untranslated region, part of intron 1, part of the 3' untranslated region, and the complete coding region of the phospholamban gene in dogs with DCM. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that mutations in the phospholamban gene are not a frequent cause of DCM in Doberman Pinschers, Newfoundlands, and Great Danes. 相似文献
146.
147.
Hensel A Nikolaou K Bartling C Petry T Arnold T Rösler U Czerny CP Truyen U Neubauer H 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(1-2):30-38
The aim of the present study was to provide current data on the prevalence of anti-Yersinia-antibodies in Bavarian slaughtering pigs. The recomBlot Westernblot assay based on five recombinantly produced Yersinia Outer Proteins (YopD, YopE, YopH, YopM, V-antigen) is well evaluated for the use in the diagnosis of human yersiniosis and proved to be also a valuable tool for the detection of porcine antibodies. 965 out of 1002 meat juice samples collected in 53 Bavarian pig farms contained anti-Yop/V-Ag-antibodies. Only blots with three or more detectable signals were considered as positive. On the basis of these results a possible previous history of Yersinia infection was detected in 45.4% of the pigs and all of the pig farms. The high prevalence of anti-Yersinia-antibodies found in this investigation demonstrates the need for further epidemiological surveillance and animal studies to assess consumers' endangering. 相似文献
148.
Wauchope RD Ahuja LR Arnold JG Bingner R Lowrance R van Genuchten MT Adams LD 《Pest management science》2003,59(6-7):691-698
We present an overview of USDA Agricultural Research Service (ARS) computer models and databases related to pest-management science, emphasizing current developments in environmental risk assessment and management simulation models. The ARS has a unique national interdisciplinary team of researchers in surface and sub-surface hydrology, soil and plant science, systems analysis and pesticide science, who have networked to develop empirical and mechanistic computer models describing the behavior of pests, pest responses to controls and the environmental impact of pest-control methods. Historically, much of this work has been in support of production agriculture and in support of the conservation programs of our 'action agency' sister, the Natural Resources Conservation Service (formerly the Soil Conservation Service). Because we are a public agency, our software/database products are generally offered without cost, unless they are developed in cooperation with a private-sector cooperator. Because ARS is a basic and applied research organization, with development of new science as our highest priority, these products tend to be offered on an 'as-is' basis with limited user support except for cooperating R&D relationship with other scientists. However, rapid changes in the technology for information analysis and communication continually challenge our way of doing business. 相似文献
149.
This paper is an overview of a non-specific local early induced resistance (EIR) mechanism, distinct from the incompatible-specific hypersensitive reaction (HR). We have shown that the local induced resistance (LIR) described earlier is not a single and uniform response to pathogen infection, because an early (EIR) and a late form can be distinguished. EIR operates from 3-6 h post-inoculation (hpi) until about 20 hpi, and is inhibited by a short heat-shock or the eukaryotic protein synthesis inhibitor, cycloheximide. In contrast, LIR, which corresponds to the induced resistance forms discovered earlier, requires more time (about 24 h) and intensive illumination to develop, and is effective for a longer period. EIR develops parallel with HR and is sometimes able to prevent it when the induction time of HR is longer than the time required for the development of EIR. It seems that EIR inhibits the metabolism of bacteria and the activity of hrp genes which otherwise are required for the induction of HR. In a compatible host-pathogen relationship the effect of EIR fails to take place. The rapid development of EIR is greatly influenced by temperature and the physiological state of the plant. EIR activates the accumulation of hydrogen peroxide at the bacterial attachment, expressing new peroxidase isoenzymes in the initiated plant tissue. It seems that this is a native general local defence mechanism which can localise foreign organisms even at the penetration site. 相似文献
150.
Dietrich U Arnold P Guscetti F Pfyffer GE Spiess B 《The Journal of small animal practice》2003,44(3):121-125
Disseminated mycobacterial disease was diagnosed in an eight-year-old domestic shorthaired cat, with involvement of the skin, lungs, lymph nodes and one eye. Mycobacterium simiae was cultured from skin biopsies on solid agar and in liquid media. This organism is known to cause pulmonary, cutaneous or disseminated infection in human patients with acquired immunodeficiency syndrome but has never been encountered as a pathogen in companion animals. Combination treatment with rifampicin, enrofloxacin and clarithromycin resulted in complete clinical remission within six months, with no side effects. No recurrence was observed in a 22-month follow-up period. 相似文献