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11.
Beckmann L Müller M Luber P Schrader C Bartelt E Klein G 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(11-12):487-490
Foodborne infections with Campylobacter spp. are increasing, especially antibiotic resistant strains are emerging. Quinolone resistant isolates can cause failure of therapy in severe clinical infections. Molecular characterisation is needed for the detection of resistant variants of C. jejuni. Therefore 23 isolates from poultry and human medicine as well as three control strains were tested for their minimal inhibitory concentration, their Single-Strand-Conformation-Polymorphism (SSCP)-PCR pattern (a method for the detection of resistance determining point mutations), and their sequence of the quinolone resistance determining region (QRDR). Six different SSCP types could be identified: two types for quinolone resistant isolates and other types containing so called silent mutations without influence on the resistance. A genotypic monitoring of the quinolone resistance in C. jejuni can be useful for the early detection of new resistance variants. As a screening method for detection of point mutations in the QRDR the SSCP-PCR can be applied. Compared to other genotypic methods the SSCP-PCR is less time and cost consuming and needs only standard technical equipment. 相似文献
12.
Dorn C Schroeter A Helmuth R 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(7-8):252-258
The National Salmonella Reference Laboratory (NRL-Salm) of the Federal Institute for Health Protection of Consumers and Veterinary Medicine receives putative Salmonella isolates originating from animals, food, feed and the environment for typing. This report summarises the results of the sero- and phagetyping studies. In livestock S. Typhimurium DT 104 with 24% and S. Enteritidis PT 4 with 9% of all isolations predominate like in the human isolates. These sero- and phagetypes are frequently isolated from food as well and consequently can reach the consumer via the food chain. 相似文献
13.
ABSTRACT The effects of host genotype mixtures on disease progression and pathogen evolution are not well understood in pathosystems that vary quantitatively for resistance and pathogenicity. We used four mixtures of moderately resistant and susceptible winter wheat cultivars naturally inoculated with Mycosphaerella graminicola to investigate impacts on disease progression in the field, and effects on pathogenicity as assayed by testing isolate populations sampled from the field on greenhousegrown seedlings. Over 3 years, there was a correspondence between the mixtures' disease response and the pathogenicity of isolates sampled from them. In 1998, with a severe epidemic, mixtures were 9.4% less diseased than were their component pure stands (P = 0.0045), and pathogen populations from mixtures caused 27% less disease (P = 0.085) in greenhouse assays than did populations from component pure stands. In 1999, the epidemic was mild, mixtures did not reduce disease severity (P = 0.39), and pathogen populations from mixtures and pure stands did not differ in pathogenicity (P = 0.42). In 2000, epidemic intensity was intermediate, mixture plots were 15.2% more diseased than the mean of component pure stands (P = 0.053), and populations from two of four mixtures were 152 and 156% more pathogenic than the mean of populations from component pure stands (P = 0.043 and 0.059, respectively). Mixture yields were on average 2.4 and 6.2% higher than mean component pure-stand yields in 1999 and 2000, respectively, but the differences were not statistically significant. The ability of mixtures challenged with M. graminicola to suppress disease appears to be inconsistent. In this system, host genotype mixtures evidently do not consistently confer either fitness benefits or liabilities on pathogen populations. 相似文献
14.
Influence of lidocaine and diazepam on peri-induction intraocular pressures in dogs anesthetized with propofol–atracurium 下载免费PDF全文
Erik H. Hofmeister Clara O. Williams Christina Braun Phillip Anthony Moore 《Canadian journal of veterinary research》2006,70(4):251-256
The purpose of this study was to evaluate the effects on the intraocular pressure (IOP) of lidocaine or diazepam administered intravenously (IV) before induction of anesthesia with propofol-atracurium and orotracheal intubation in normal dogs, as well as the effects on the IOP of lidocaine applied topically to the larynx after induction with propofol-atracurium. We randomly assigned 32 random-source dogs, obtained from municipal pounds, to receive the following: lidocaine, 2 mg/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (LIDOsal); saline, 0.1 mL/kg IV, with lidocaine, 2 mg/kg topically applied to the larynx (SALlido); diazepam (Valium), 0.25 mg/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (VALsal); or saline, 0.1 mL/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (SALsal). We measured arterial pressure directly, by means of an indwelling catheter placed in a peripheral artery. Anesthesia was induced with propofol, 8 mg/kg IV, until loss of jaw tone, followed by atracurium, 0.3 mg/kg IV. We measured the IOP in triplicate in each eye before premedication, before induction, before intubation, and after intubation. After induction, the IOP was significantly increased except in the VALsal group, in which the IOP was significantly lower than in the negative-control group before intubation. After intubation, the IOP was significantly elevated in all the groups compared with the values before induction. Cardiovascular parameters were essentially similar in all the groups, except for a significant increase in blood pressure after intubation in the SALlido group. Thus, propofol-atracurium anesthesia causes an increase in IOP that is blunted by diazepam. However, diazepam does not blunt the increase in IOP observed with intubation. 相似文献
15.
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
16.
Christina von ZallingerDVM Karlheinz TempelDVM 《Veterinary radiology & ultrasound》1998,39(6):495-503
With respect to clinical signs of the radiation syndromes, some remarkable species variations exist. For example the marked delayed reaction of the acute hematologic response in cows. An unusually high sensitivity of the central nervous system is found in burros, which is probably caused by acute vascular and/or metabolic changes in the brain. The species-specific number of intestinal crypt and hemopoietic stem cells may explain the early survival differences among species after high doses of irradiation. Mortality due to acute radiation syndromes is lowest in chickens. Regarding late effects, various neoplasms are typical in dogs, and cattle more commonly develop cataracts. 相似文献
17.
Hewes CA Keoughan GC Gutierrez-Nibeyro S 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(5):512-514
Enucleation was performed in 5 horses under local anesthesia and sedation with the horse standing. Minimal hemorrhage occurred during the surgical procedure, and there were no other reported complications. Standing enucleation is a surgery that is safe to perform in horses. 相似文献
18.
Fassbender M Hildebrandt TB Paris MC Colenbrander B Jewgenow K 《The Journal of reproduction and development》2007,53(5):1023-1034
Transplantation of ovarian tissue has high potential for female gamete conservation. However, optimal timing of oocyte recovery for in vitro maturation and fertilization is still critical. Therefore the aim of the present study was to use high-resolution transcutaneous ultrasonography to monitor follicular development within xenografted ovarian tissue. Ovarian cortex fragments (n=44) from domestic cats were transplanted into athymic nude rats (n=12). Graft development in the animals was assessed weekly by high frequency ultrasound (10-22 MHz) under two different FSH regimes. Blood collection for serum estradiol determination and vaginal smears were performed simultaneously. The xenografts were removed at different time points according to the ultrasound findings. The survival rate of the transplants 4 weeks after surgery was 54.5% and antral follicular growth was observed within 10 grafts from 5 different hosts (8.6 +/- 6.43 follicles per graft). Early follicle antrums could be detected from 0.4 mm onwards. The growth rate of the antral cavity was calculated from weekly measurements (0.56 +/- 0.44 mm per week). Although vaginal cells and estradiol levels followed a cyclic pattern, no correlation was found between follicular diameter, estradiol and keratinized vaginal cells. We recovered 5, 1 and 4 cumulus oocyte complexes from three different individuals during weeks 19, 21, and 23 respectively. Extrusion of a polar body (1 oocyte) and germinal vesicle break down (7 oocytes) indicated progression of maturation after in vitro culture. We conclude that ultrasonography und provided a reliable method to examine xenograft survival and follicular development within the grafts. Furthermore, this technique is suitable for assessment of the efficiency of hormonal treatment and narrowing of the optimal time frame for oocyte retrieval. To our knowledge, this is the first report of the in vivo development of early antral follicles in mammalian species. 相似文献
19.
Erik H. Hofmeister Jane Quandt Christina Braun Molly Shepard 《Veterinary anaesthesia and analgesia》2014,41(3):243-248
ObjectiveTo determine the incidence of anesthesia patient safety incidents at a university teaching hospital, develop interventions to address the most common incidents, and determine the effectiveness of these interventions.Study designPre-post intervention observational.AnimalsFour thousand, one hundred forty dogs and cats anesthetized by the anesthesia service.MethodsThe study was divided into two 11.5 month periods. During each period, incidents were logged (e.g. closed adjustable pressure limiting (APL) valve, esophageal intubation, and medication error). At the end of the first period, four countermeasures were incorporated into the service’s protocols: 1) prior to any drug injection, the individual would read out aloud the drug name, patient name, and route of administration; 2) use of a uniquely colored occlusive wrap over arterial catheters; 3) a check box on the anesthesia record labeled “Technician Confirmed Intubation”; 4) a check box on the anesthesia record labeled “Technician Checked OR (operating room)”. The number of patient safety incidents during period 1 and period 2 were compared using Fisher’s Exact Test.ResultsDuring Period 1, there were 74 incidents documented in 2028 patients (3.6%) including 25 medication errors, 20 closed APL valves, and 16 of esophageal intubation. During Period 2, there were 30 incidents documented in 2112 patients (1.4%) including 14 medication errors, 5 closed APL valves, and 4 of esophageal intubation. The proportion of events during Period 2 was significantly smaller than during Period 1 (p < 0.0001).Conclusions and Clinical relevanceImplementation of four simple interventions was associated with a significant decrease in the number of incidents. 相似文献
20.
Stefanie B. Campbell Anna Klioueva Jeff Taylor Christina Nelson Suzanne Tomasi Adam Replogle Natalie Kwit Christopher Sexton Amy Schwartz Alison Hinckley 《Zoonoses and public health》2019,66(6):579-586
Tick‐borne relapsing fever (TBRF) is a potentially serious spirochetal infection caused by certain species of Borrelia and acquired through the bite of Ornithodoros ticks. In 2017, Austin Public Health, Austin, TX, identified five cases of febrile illness among employees who worked in caves. A cross‐sectional serosurvey and interview were conducted for 44 employees at eight organizations that conduct cave‐related work. Antibodies against TBRF‐causing Borrelia were detected in the serum of five participants, four of whom reported recent illness. Seropositive employees entered significantly more caves (Median 25 [SD: 15] versus Median 4 [SD: 16], p = 0.04) than seronegative employees. Six caves were entered more frequently by seropositive employees posing a potentially high risk. Several of these caves were in public use areas and were opened for tours. Education of area healthcare providers about TBRF and prevention recommendations for cavers and the public are advised. 相似文献