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61.
OBJECTIVE: To determine the effect of morphine administered prior to anesthesia on the incidence of gastroesophageal reflux (GER) in dogs during the subsequent anesthetic episode. ANIMALS: 90 dogs (30 dogs/group). PROCEDURE: The randomized prospective clinical study included healthy dogs with no history of vomiting. Dogs were scheduled to undergo elective orthopedic surgery. Food was withheld for (mean+/-SD) 17.8+/-4.1 hours prior to induction of anesthesia. The anesthetic protocol included acepromazine maleate, thiopental, and isoflurane. Dogs were randomly selected to receive morphine at various dosages (0, 0.22, or 1.10 mg/kg, IM) concurrent with acepromazine administration prior to induction of anesthesia. A sensor-tipped catheter was used to measure esophageal pH, and GER was defined as a decrease in pH to < 4 or an increase to > 7.5. RESULTS: 40 dogs had acidic reflux, and 1 had biliary reflux. Proportions of dogs with GER were 8 of 30 (27%), 15 of 30 (50%), and 18 of 30 (60%) for morphine dosages of 0, 0.22, and 1.10 mg/kg, respectively. Mean duration of GER was 91.4+/-56.8 minutes. There was no significant association between GER and age, weight, vomiting after preanesthetic medication, administration of antimicrobials, or start of surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Most healthy dogs vomit after a large dose of morphine, but vomiting does not increase the likelihood of GER during the subsequent anesthetic episode. Administration of morphine prior to anesthesia substantially increases the incidence of GER during the subsequent anesthetic episode. 相似文献
62.
Charles C. Grier Katherine J. Elliott Deborah G. McCullough 《Forest Ecology and Management》1992,50(3-4):331-350
Above-ground biomass distribution, leaf area, above-ground net primary productivity and foliage characteristics were determined for 90- and 350-year-oldPinus edulis-Juniperus monosperma ecosystems on the Colorado Plateau of northern Arizona. These ecosystems have low biomass, leaf area and primary productivity compared with forests in wetter environments. Biomass of the 350-year-old pinyon-juniper stand examined in this study was 54.1 mg ha−1; that of the 90-year-old stand was 23.7 mg ha−1. Above-ground net primary production averaged 2.12 mg ha−1 year−1 for the young and 2.88 mg ha−1 year−1 for the mature stand; tree production was about 80% of these values for both stands. Projected ecosystem leaf area (LAI) of the stands was 1.72 m2 m−2 and 1.85 m2 m−2, respectively. Production efficiency (dry matter production per unit leaf area) was 0.129 kg m−2 year−1 for the young, and 0.160 kg m−2 year−1 for the mature stand. Production efficiency of the study sites was below the 0.188 kg m−2 year−1 reported for xeric, pure juniper stands in the northern Great Basin. Biomass of pinyon-juniper ecosystems of northern Arizona is generally below the 60–121 mg ha−1 reported for pinyon-juniper stands of the western Great Basin in Nevada. A climatic gradient with summer precipitation decreasing between southeast Arizona and northwest Nevada occurs in the pinyon-juniper region. Great Basin pinyon-juniper ecosystems lie at the dry-summer end of this gradient while pinyon-juniper ecosystems of the Colorado Plateau lie at about the middle of this gradient. In spite of wetter summers, pinyon-juniper ecosystems of northern Arizona are less productive than those of the Great Basin. 相似文献
63.
Deborah A. O''Keefe DVM MS David J. Schaeffer PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(5):276-282
The hematologic toxicity of doxorubicin, 30 mg/m2 body surface area (BSA) every 21 days to a cumulative dose of 300 mg/m2, was evaluated in six cats. Complete blood and platelet counts were performed daily during the first treatment cycle. They were monitored before treatment for all remaining cycles, and at the average neutrophil nadir (day 8) starting with cycle 4. Significant poikilocytosis developed after the first treatment and remained throughout the study, although anemia did not occur. No other red blood cell abnormalities were seen. Platelet counts remained within the reference range throughout the first treatment cycle, but mild thrombocytopenia (88,000-288,000/uL) was found in 11.3% of subsequent complete blood counts (CBCs). Thrombocytosis was seen in 30.9% of CBCs. Neutropenia did not occur during the first treatment cycle although neutrophil counts did decrease, with the nadir occurring between days 8 and 11. All neutrophil counts returned to pretreatment values by day 14. Neutropenia was documented after 14 of 46 (30.4%) doxorubicin treatments, and was associated with fever in 5 cats (10.9%). All fevers responded to oral antibiotic therapy. Neutropenia that lasted more than 14 days developed in two cats, necessitating dosage reduction to 25 mg/m2 BSA. At the dose used in this study, doxorubicin administration was associated with acceptable hematologic toxicosis in most cats. 相似文献
64.
Silverstein Dombrowski DC Carmichael KP Wang P O'Malley TM Haskins ME Giger U 《Journal of the American Veterinary Medical Association》2004,224(4):553-7, 532-3
A 12-week-old male German Shepherd Dog was evaluated because of a 3-week history of a progressive inability to ambulate. Clinical and laboratory findings included skeletal deformities, corneal cloudiness, cytoplasmic granules in the neutrophils and lymphocytes of blood and CSF and glycosaminoglycans in a urine sample (detected via a toluidine blue spot test). Enzyme activity and DNA analyses confirmed mucopolysaccharidosis type VII as a result of severe beta-glucuronidase deficiency; this condition had been identified in a mixed-breed dog (likely of German Shepherd Dog descent) that was reported 20 years earlier and caused by the same missense mutation. Because of the progressive nature of this disease, the puppy was euthanatized and all tissues examined contained evidence of lysosomal storage leading to marked cellular distention. Mucopolysaccharidosis type VII is only one of many hereditary lysosomal storage diseases identified in companion animals. It is important that clinicians recognize the typical signs of lysosomal storage diseases and are aware of the cytologic and urinary screening tests for mucopolysaccharidosis disorders. Furthermore, there are specific blood enzyme and DNA-based tests to distinguish the forms of mucopolysaccharidosis in affected and carrier animals. 相似文献
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Thrice out of Africa: ancient and recent expansions of the honey bee, Apis mellifera 总被引:1,自引:0,他引:1
Whitfield CW Behura SK Berlocher SH Clark AG Johnston JS Sheppard WS Smith DR Suarez AV Weaver D Tsutsui ND 《Science (New York, N.Y.)》2006,314(5799):642-645
We characterized Apis mellifera in both native and introduced ranges using 1136 single-nucleotide polymorphisms genotyped in 341 individuals. Our results indicate that A. mellifera originated in Africa and expanded into Eurasia at least twice, resulting in populations in eastern and western Europe that are geographically close but genetically distant. A third expansion in the New World has involved the near-replacement of previously introduced "European" honey bees by descendants of more recently introduced A. m. scutellata ("African" or "killer" bees). Our analyses of spatial transects and temporal series in the New World revealed differential replacement of alleles derived from eastern versus western Europe, with admixture evident in all individuals. 相似文献
70.
Wood AC Fine DM Spier AW Eyster GE 《Journal of the American Veterinary Medical Association》2006,228(12):1901-1904
CASE DESCRIPTION-A 12-week-old female English Springer Spaniel was evaluated for lethargy, vomiting, and pyrexia 1 week after treatment of patent ductus arteriosus (PDA) via coil occlusion. CLINICAL FINDINGS-Test results were consistent with septicemia, and the assumption was made that the PDA occlusion coils were infected. Radiography revealed partial migration of the coil mass into the pulmonary artery and signs of congestive heart failure. TREATMENT AND OUTCOME-After successful treatment of the septicemia and heart failure, surgical removal of the coils and resection of the PDA were undertaken. Although the coil that embolized to the pulmonary vasculature was left in place, the dog's clinical signs resolved. CLINICAL RELEVANCE-This case highlights the fact that as PDA coil occlusion devices become more widely used in dogs, practitioners must be prepared to treat implant infections aggressively, with both medical and surgical interventions if necessary. 相似文献