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161.
Recent studies have highlighted concerns regarding the skills, career prospects, and economic prosperity of veterinarians. Human resource departments in a wide variety of organizations and industries have adopted a competency-based approach to managing the selection, training, placement, and ongoing development of their staff. This paper defines competencies, characterizes their typical use in industry, and examines the potential applications of a competency-based approach for veterinary medicine. It is argued that the competency-based approaches honed in the private sector promise to assist veterinary colleges, employers of veterinarians, and professional societies in influencing the state of the profession through the selection, education, and development of veterinarians.  相似文献   
162.
Precipitation samples were collected at Davis and Lake Tahoe, California, in 1972–73 and 1977–78 and analyzed for pH and major cations and anions. Rain and snow in this region of northern California are derived primarily from winter cyclonic storms which move easterly from the Pacific Ocean over Davis and then Lake Tahoe. Precipitation at both sites was found to be more acid than water in equilibrium with atmospheric CO2. Acidity at Lake Tahoe apparently increased over the 5-yr period of the study. Sulfate was the dominant acid anion in 1972–73 (not measured in 1977–78). A major source of sulfate in precipitation was probably industry in the San Francisco Bay Area, upwind of the study sites. Automobile exhaust emissions throughout the region, which contains three major interstate highways and several large urban centers, contribute both sulfate and nitrate precursors to the atmosphere. As in the Eastern United States, these strong acid anions are influencing precipitation chemistry in northern California, including the Sierra Nevada mountains.  相似文献   
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Bookshelf     
Exotic Diseases of Animals: a field guide for Australian veterinarians , Geering WA, Forman AJ and Nunn MJ
Student's Guide to Bovine Clinics , 2nd edition, C Pasquini & S Pasquini  相似文献   
166.

Objective

Propranolol has been suggested for anxiolysis in horses, but its sedation efficacy and side effects, both when administered alone and in combination with α2-adrenoceptor agonists, remain undetermined. This study aimed to document the pharmacokinetics and pharmacodynamics of propranolol, romifidine and their combination.

Study design

Randomized, crossover study.

Animals

Six adult horses weighing 561 ± 48 kg.

Methods

Propranolol (1 mg kg?1; treatment P), romifidine (0.1 mg kg?1; treatment R) or their combination (treatment PR) were administered intravenously with a minimum of 1 week between treatments. Alertness, behavioral responsiveness (visual and tactile) and physiologic variables were measured before and up to 960 minutes after drug administration. Blood was collected for blood gas and acid-base analyses and measurement of plasma drug concentrations. Data were analyzed using repeated-measures analysis of variance or Friedman with Holm–Sidak and Wilcoxon rank-sum tests (p < 0.05).

Results

Systemic clearance significantly decreased and the area under the concentration-time curve significantly increased for both drugs in PR compared with P and R. Both PR and R decreased behavioral responsiveness and resulted in sedation for up to 240 and 480 minutes, respectively. Sedation was deeper in PR for the first 16 minutes. Heart rate significantly decreased in all treatments for at least 60 minutes, and PR significantly increased the incidence of severe bradycardia (<20 beats minute?1).

Conclusions and clinical relevance

Although not associated with reduced behavioral responsiveness or sedation alone, propranolol augmented romifidine sedation, probably through alterations in romifidine pharmacokinetics, in horses administered PR. The occurrence of severe bradycardia warrants caution in the co-administration of these drugs at the doses studied.  相似文献   
167.
BACKGROUND: Helicobacter pylori is a common cause of gastritis and peptic ulcers in humans. Many dogs, including those with gastritis and chronic vomiting, are infected with Helicobacter spp. HYPOTHESIS: Triple antimicrobial therapy will eradicate Helicobacter infection, improve gastritis, and reduce clinical signs. The addition of acid suppression medication will not improve results. ANIMALS: Twenty-four pet dogs with chronic vomiting and gastric Helicobacter spp. METHODS: Dogs were randomly assigned to triple antimicrobial therapy with or without famotidine. Gastroduodenoscopy was performed 4 weeks and 6 months after therapy. Helicobacter spp status was determined by histologic assessment of gastric mucosal biopsy specimens. RESULTS: Eradication rates for each treatment were not significantly different and combined were 75 and 42.9% at 4 weeks and 6 months, respectively. A greater improvement in gastritis scores occurred in dogs that became Helicobacter spp negative. Overall, the frequency of vomiting was reduced by 86.4%, but there were no differences between treatments. CONCLUSIONS AND CLINICAL IMPORTANCE: Eradication rates of Helicobacter spp with both treatments were not significantly different. Eradication rates at 6 months were modest, and more effective treatments should be developed. Acid suppression is not a necessary component of treatment protocols for dogs. Eradication of gastric Helicobacter spp was associated with improvement in gastritis scores. Dramatic reduction of the vomiting frequency occurred with both treatment protocols. Gastric Helicobacter spp may cause or contribute to chronic vomiting and gastritis in some dogs.  相似文献   
168.
Non-methylated CpG motifs, present in viral and bacterial DNA, are one of many pathogen-associated molecular patterns (PAMP) recognized by the mammalian innate immune system. Recognition of this PAMP occurs through a specific interaction with toll-like receptor 9 (TLR9) and this interaction can induce cytokine responses that influence both innate and adaptive immune responses. Previous investigations determined that both the flanking sequences in synthetic CpG oligodeoxynucleotides (CpG ODN) and the cellular pattern of TLR9 expression can influence species-specific responses to CpG ODN. Therefore, the structure, function and cellular distribution of bovine TLR9 were compared with what is known for mice and human. Analysis of the bovine TLR9 gene revealed greater sequence homology between cattle and humans than cattle and mice Similar CpG motifs induced optimal activation of both human and bovine leukocytes and these motifs were distinct from those which activated mouse leukocytes. Functional analyses with CpG ODN stimulated bovine blood leukocytes revealed that class A CpG ODN were more potent inducers of interferon-alpha (IFN-alpha) than class B CpG ODN. Furthermore, magnetic activated cell sorting of bovine blood leukocyte subpopulations implicated dendritic cells but not monocytes in the regulation of CpG ODN-induced IFN secretion. Thus, the cellular pattern of CpG ODN-induced responses in cattle shared many similarities with human leukocytes. Collectively, these analyses revealed substantial conservation of TLR9 structure and TLR9 function in blood leukocytes of humans, cattle and other domestic species.  相似文献   
169.
A retrospective study of the use of intraoperative mesenteric portovenography (IOMP) in the surgical management of congenital portosystemic shunts in 100 dogs and cats was performed. Each portovenogram was scored using a subjective visual analogue scale (VAS) and was assessed for the presence of portal atresia or hypoplasia. VAS scores and portal hypoplasia assessments were obtained for portovenogram images obtained for each animal both before shunt manipulation (preligation) and following the temporary, complete ligation of the vessel (postligation). In each patient, surgical records were reviewed to ascertain the degree of shunt attenuation that was achieved at surgery. Hepatic portal vasculature was significantly different on postligation compared with preligation IOMP. Sixty-two percent of animals had apparent portal hypoplasia or atresia on their preligation IOMP. The majority of these (81%) had an improvement in portal vasculature on postligation IOMP. It was concluded that both preligation and postligation IOMP provided valuable information regarding the morphology of congenital portosystemic shunts. An accurate assessment of an animal's portal vasculature could only be made following the interpretation of a postligation portovenogram, and these findings significantly influenced the surgical management of the patient. Although individuals with high postligation VAS scores were more likely to achieve full shunt attenuation at surgery, there was no quantifiable relationship between IOMP findings and the degree of shunt attenuation achieved.  相似文献   
170.
The therapeutic efficacy and field safety of tulathromycin were evaluated in stocker calves with undifferentiated bovine respiratory disease (BRD) in three field studies conducted over two consecutive grazing seasons in Nebraska. Eight hundred calves exhibiting clinical signs of BRD and with rectal temperatures of 104 degrees F or higher were treated with tulathromycin (n = 340), florfenicol (n = 240), or tilmicosin (n = 220) and evaluated for approximately 60 days. Florfenicol and tilmicosin were administered as single SC injections according to labeled dosage. Tulathromycin was administered as a single SC injection of 2.5 mg/kg. In all three studies, the cure rate of calves 60 days after treatment with tulathromycin was significantly higher (P < or = .05) than that of calves treated with florfenicol or tilmicosin. Suspected adverse reactions were not reported for any of the study drugs. Tulathromycin proved to be significantly more effective than either florfenicol or tilmicosin in the treatment of BRD in stocker calves.  相似文献   
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