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81.
82.
ObjectiveTo evaluate the effects of butorphanol on cardiopulmonary parameters in dogs anesthetized with desflurane and breathing spontaneously.Study designProspective, randomized experimental trial.AnimalsTwenty dogs weighing 12 ± 3 kg.MethodsAnimals were distributed into two groups: a control group (CG) and butorphanol group (BG). Propofol was used for induction and anesthesia was maintained with desflurane (10%). Forty minutes after induction, the dogs in the CG received sodium chloride 0.9% (0.05 mL kg?1 IM), and dogs in the BG received butorphanol (0.4 mg kg?1 IM). The first measurements of body temperature (BT), heart rate (HR), arterial pressures (AP), cardiac output (CO), cardiac index (CI), central venous pressure (CVP), stroke volume index (SVI), pulmonary arterial occlusion pressure (PAOP), mean pulmonary arterial pressure (mPAP), left ventricular stroke work (LVSW), systemic (SVR) and pulmonary (PVR) vascular resistances, respiratory rate (fR), and arterial oxygen (PaO2) and carbon dioxide (PaCO2) partial pressures were taken immediately before the administration of butorphanol or sodium chloride solution (T0) and then at 15-minute intervals (T15–T75).ResultsIn the BG, HR, AP, mPAP and SVR decreased significantly from T15 to T75 compared to baseline. fR was lower at T30 than at T0 in the BG. AP and fR were significantly lower than in the CG from T15 to T75. PVR was lower in the BG than in the CG at T30, while PaCO2 was higher compared with T0 from T30 to T75 in the BG and significantly higher than in the CG at T30 to T75.Conclusions and clinical relevanceAt the studied dose, butorphanol caused hypotension and decreased ventilation during desflurane anesthesia in dogs. The hypotension (from 86 ± 10 to 64 ± 10 mmHg) is clinically relevant, despite the maintenance of cardiac index.  相似文献   
83.
ObjectiveTo determine the magnitude and duration of sevoflurane minimum alveolar concentration (MAC) reduction following a single intravenous (IV) dose of methadone in cats.Study designProspective experimental study.AnimalsEight (four females and four males) healthy mixed-breed adult (1–2 years) cats weighing 5.82 ± 0.42 kg.MethodsAnesthesia was induced and maintained with sevoflurane. Intravenous catheters facilitated administration of methadone and lactated Ringer’s solution. After baseline MAC determination in triplicate using a tail clamp technique, 0.3 mg kg?1 of methadone was administered IV. End-tidal sevoflurane concentration (e′SEVO) was reduced and MAC was redetermined. In an effort to determine the duration of MAC reduction, measurements were repeated in a stepwise manner until MAC values returned to baseline. After the last stimulation, the e′SEVO was increased to 1.2 individual MAC for 15 minutes, then sevoflurane was discontinued and cats were allowed to recover from anesthesia.ResultsBaseline sevoflurane MAC was 3.18 ± 0.06%. When compared with baseline the sevoflurane MAC after methadone administration was significantly reduced by 25, 15 and 7% at 26, 76 and 122 minutes, respectively. The final MAC value (3.09 ± 0.07%) determined 156 minutes after methadone administration was not significantly different from baseline.Conclusions and clinical relevanceIntravenous methadone (0.3 mg kg?1) significantly decreased MAC of sevoflurane in cats but the effect was short-lived.  相似文献   
84.
ObjectiveTo determine the incidence of canine post-anesthetic aspiration pneumonia (AP) and to identify anesthetic agents, procedures and management factors associated with the development of AP.Study designMulticenter, randomized, case-controlled retrospective study.AnimalsTwo hundred and forty dogs affected with AP and 488 unaffected control dogs.MethodsElectronic medical record databases at six Veterinary colleges were searched for dogs, coded for anesthesia or sedation and pneumonia from January 1999 to December 2009. The resultant 2158 records were hand-searched to determine eligibility for inclusion. Diagnosis of AP was made radiographically. Two unaffected control dogs were randomly selected for each affected dog, from a list of dogs that underwent sedation or anesthesia in the same time period and did not develop aspiration pneumonia. Fifty-seven factors were then evaluated for association with aspiration pneumonia. Data analysis was performed using univariate Chi-square or student t-tests, then multivariate logistic regression.ResultsIncidence of post-anesthetic AP was 0.17%, from 140,711 cases anesthetized or sedated over the 10 year period. Two anesthesia-related events were significantly associated with development of AP: regurgitation and administration of hydromorphone at induction. Administration of anticholinergics was not associated with AP. Procedures associated with increased odds of aspiration pneumonia included laparotomy, upper airway surgery, neurosurgery, thoracotomy and endoscopy. Orthopedic surgery, ophthalmologic surgery, dental procedures, MRI, CT, bronchoscopy, cystoscopy, tracheoscopy and neutering were not associated with development of AP. Three patient factors were associated with the development of AP: megaesophagus, and a history of pre-existing respiratory or neurologic disease. Sixty-nine% of dogs with two or more of the above independent predictive variables developed AP.Conclusion and clinical relevanceMost anesthetic agents and procedures were not associated with the development of AP. We need to devise and evaluate strategies to protect at risk patients.  相似文献   
85.
The tomato chlorosis virus (ToCV), transmitted by whitefly species of the genera Bemisia and Trialeurodes in a semipersistent manner, causes significant losses in solanaceous crops including tomato (Solanum lycopersicum) and sweet pepper (Capsicum annuum). Worldwide reports of natural and experimental infection of sweet pepper plants with ToCV are contradictory, raising the question of whether the critical factor determining infection is related to the susceptibility of sweet pepper cultivars or the genetics of virus isolates. In this work, ToCV isolates obtained from different hosts and geographical origins were biologically and molecularly analysed, transmitted by B. tabaci MEAM1 and MED, and the reaction of different sweet pepper cultivars was evaluated under different environmental conditions. Brazilian ToCV isolates from tomato, potato (S. tuberosum), S. americanum, and Physalis angulata did not infect plants of five sweet pepper cultivars when transmitted by B. tabaci MEAM1. Temperatures did not affect the sweet pepper susceptibility to tomato-ToCV isolates from São Paulo, Brazil, and Florida, USA. However, sweet pepper-ToCV isolates from Spain and São Paulo, Brazil, were transmitted efficiently to sweet pepper plants by B. tabaci MEAM1 and MED. Although the results indicated that ToCV isolates from naturally infected sweet pepper plants seem to be better adapted to plants of C. annuum, phylogenetic analyses based on the complete nucleotide sequences of RNA1 and RNA2 as well as the p22 gene did not reveal significant nucleotide differences among them. Additional studies are needed to identify intrinsic characteristics of ToCV isolates that favour infection of sweet pepper plants.  相似文献   
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87.
The influence of tilapia cages on limnological characteristics of the Chavantes Reservoir, Paranapanema River, Brazil, was investigated in March and June 2007. Principal components analysis was used to compare the transparency; dissolved oxygen; temperature; total organic nitrogen, phosphorus, and dissolved solids; chlorophyll a and electrical conductivity of fish farm 1 (239.3 m.t.), 2 (461.5 m.t.) and areas without cages, in the lacustrine and river‐reservoir transition regions. The variables differentiated the regions and areas with and without cages. In March, in the lacustrine region, there was a thermal and chemical stratification, and in the transition region, there was a temperature and oxygen reduction gradient between the surface and bottom that was also observed in June in fish farm 1. The higher transparency confirmed the increased light penetration in the lacustrine region. In the transition region, there were higher turbidity, total dissolved solid, and conductivity values that are likely related to allochthonous material flow and transport. In fish farms, lower oxygen and pH values indicate intense decomposition and respiration. The generally higher total dissolved solid and nutrient values, turbidity, and conductivity and the lower transparency in one or both fish farms indicate their contribution to eutrophication, demonstrating the need for careful monitoring.  相似文献   
88.
Lacewings and lady beetles represent two important groups of natural enemies for pest control. Kaolin is used in various crop ecosystems to reduce abiotic plant stressors and pest colonization. Compatible methods aimed at reducing abiotic and biotic plant stressors are desired in crop management systems. Therefore, this work evaluated the development and survival of Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) and Eriopis connexa (Germar) (Coleoptera: Coccinellidae) larvae of different ages treated with kaolin at three different concentrations (ca. 60, 80, and 100 g/L) and prey consumption when treated with kaolin at a field rate of 60 g/L. The prey used were the whitefly Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) and the aphid Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae). Survival rates and development durations for E. connexa larvae topically treated with kaolin at different ages were similar to those for untreated larvae. However, larvae of C. externa reduced survival and delayed development when treated with kaolin concentrations greater than the recommended field rate. Otherwise, kaolin treatments did not affect prey consumption by larvae and adults of both predator species.  相似文献   
89.
Boron (B) application is an important strategy in highly productive systems, since this micronutrient is involved in amide syntheses, which is related to the grain yield. In this way, the aim of this work was to evaluate the B fertilization effect in nutrition and production of common beans. The experiment was carried out under greenhouse condition, in an entirely randomized design, with five B doses (0, 1, 2, 4, and 6 kg ha?1) and four repetitions. The relative chlorophyll index, dry mass production, level and accumulation of B were measured. Boron levels in leaves of common beans are linearly enhanced after application of increasing B doses. When B level in soil is low (<0.5 mg kg?1), boron doses lower than 4.9 kg ha?1 increase dry mass production, with the highest production observed at a dose of 4.8 kg ha?1, promoting a 56% in dry mass production compared with control.  相似文献   
90.
We aimed to study the behaviour of tissue renewal in blood, pectoral muscle and keel of fattening quails during their growth and adulthood through carbon‐13 turnover using the stable isotope technique. Three hundred male European quails were randomly subjected to six treatments. Diets fed to animals were initially based on corn and soybean meal and were replaced at 0, 7, 14, 21, 28 and 35 days of age with diets of rice grits and soybean meal. These diets have distinct isotopic signals and over time it changes; the tissue will incorporate dietary signal, and then, we can measure the return time for each tissue in each age. Treatments were T1 (0 to 21 days), T2 (7 to 35 days), T3 (14 to 42 days), T4 (21 to 56 days), T5 (28 to 63 days) and T6 (35 to 70 days). Carbon‐13 turnover in tissues of the birds at the above‐mentioned time periods was calculated using the first‐order exponential function. The values of half‐lives were 2.6, 3.6, 5.4, 6.3, 9.0 and 9.8 days for blood and 2.0, 1.7, 4.8, 6.7, 6.9 and 6.6 days for pectoral muscle in treatments T1, T2, T3, T4, T5 and T6 respectively. The half‐lives for the keel in treatments T2, T3, T4, T5 and T6 were 2.0, 5.4, 7.7, 8.9 and 15 days respectively. Thus, half‐life in sampled tissues generally increased with age of birds. Initially, the tissue half‐lives are influenced by growth, and at the end of the growth cycle, the breast muscle tissue was the most metabolically active in either periods, followed by blood and the keel. All tissues showed a sigmoidal growth curve, which can be confirmed by half‐life as a function of age.  相似文献   
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