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441.
Maciej Rożyński Krystyna Demska-Zakęś Agnieszka Sikora Zdzisław Zakęś 《Fish physiology and biochemistry》2018,44(3):927-937
The aim of the study was to describe the course and timing of the different stages of anesthesia induced with Propiscin (etomidate) on juvenile European perch (experiment I) and to describe the effect of immersing specimens of this species had on selected hematological and biochemical parameters (experiment II). The study was conducted on material with body weights (BW) of 162.98 (experiment I) and 171.60 g (experiment II). In experiment I, general anesthesia was induced with two different anesthetic concentrations (1 or 2 ml l?1; anesthesia time 10 min). In experiment II, blood was drawn for hematological and biochemical analyses from the fish that had been exposed to anesthetic immersion baths with two different concentrations of Propiscin (1 and 2 ml l?1) and for different exposure times (3 and 10 min). Blood samples were collected immediately following immersion (0 h) and 24 h later (24 h). Specimens that were immersed at the higher concentration of anesthetic achieved subsequent stages of general anesthesia two times faster (P ≤ 0.05). However, during recovery, some statistically significant differences were observed, but these lasted only until stage I was achieved. Among the hematological parameters (0 h), significant differences were observed in hematocrit (HCT) and mean corpuscular volume (MCV), while among the biochemical determinations (0 h), statistically significant differences were noted in the concentrations of glucose, calcium, lactate, and ammonia. After 24 h, the levels of these parameters in all fish groups returned to initial values. The hematological and biochemical tests conducted permit concluding that the anesthetic tested, at the concentrations (1 and 2 ml l?1) and the exposure times of up to 10 min at which it was tested, is safe and can be used successfully to induce general anesthesia in perch. 相似文献
442.
Claudio C. Natalini Carolina L. Krahn Priscila B.S. Serpa Joanna E. Griffith Ricardo Miyasaka de Almeida 《Veterinary anaesthesia and analgesia》2017,44(2):219-227
Objective
To investigate the efficacy of a new intravenous (IV) nanoemulsified isoflurane formulation for maintenance of general anesthesia in dogs.Study design
Prospective, crossover, experimental study.Animals
Seven healthy, mature, mixed-breed dogs, three male and four female, weighing 11.5 ± 1.5 kg.Methods
Anesthesia was induced with propofol for instrumentation. Measurements were obtained before administration of either inhaled isoflurane (Iso-I) or IV 15% isoflurane-loaded lipid nanoemulsion (Iso-nano). The minimum alveolar concentration (MAC) of isoflurane was determined using the ‘up-and-down’ technique. A tail clamp was applied every 15 minutes for a total time of 90 minutes and isoflurane administration was adjusted according to the response. Data were recorded at 30, 60 and 90 minutes for end-tidal isoflurane concentration (Fe´Iso), end-tidal carbon dioxide partial pressure (Pe′CO2), inspired isoflurane concentration (FIIso), arterial hemoglobin oxygen saturation (SaO2), peripheral hemoglobin oxygen saturation (SpO2), respiratory rate (fR), heart rate (HR), arterial blood pH, PaCO2, PaO2, base excess (BE), bicarbonate (HCO3?), systemic arterial pressure (sAP), and biochemical variables of blood urea nitrogen, alanine aminotransferase, creatine kinase and creatinine.Results
No significant differences between treatments were detected for HR, fR, SaO2 or any biochemical variables (p > 0.05). In the Iso-nano treatment, sAP was significantly decreased throughout the study. Significant decreases in pH, Pe′CO2, BE and HCO3? were measured in the Iso-nano treatment. Isoflurane MAC was significantly lower in the Iso-nano than the Iso-I treatment. The dose of isoflurane (g hour?1) required to maintain general anesthesia did not differ significantly between treatments.Conclusions and clinical relevance
Administration of 15% isoflurane-loaded lipid nanoemulsion IV was effective in maintaining general anesthesia in dogs but did not reduce the amount of isoflurane necessary to maintain general anesthesia. Significant hypotension and nonrespiratory acidosis occurred with the injectable form. 相似文献443.
Marta Joanna Monder Andrzej Pacholczak 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(3):189-198
During rhizogenesis, carbohydrates are an important source of energy for the plant tissues. It has been hypothesised that phenological phase of the shoot plays a major role in plant's response to rooting stimulants and affects the cuttings’ carbohydrate content. Therefore, the purpose of this study was to evaluate the impact of phenological phase of the shoots and the use of rooting stimulants of plant origin on the relationship between rooting abilities and the carbohydrate content in leaves and stems of cuttings. Single-node stem cuttings of Rosa beggeriana ‘Polstjärnan’ and Rosa helenae ‘Semiplena’ were harvested from shoots in four phenological stages: flower buds closed (P1), flowers open (P2), immediately after petal shedding (P3), and 7–14 days after petal fall (P4). The following rooting enhancers were used: 0.4% indole butyric acid (IBA) (Ukorzeniacz Aaqua); 0.2% naphthalene acetic acid (NAA) (Ukorzeniacz Baqua); Bio Rhizotonic; and Root Juice?; Bio Roots. Controls included untreated cuttings. The contents of reducing and total soluble carbohydrates in leaves and shoots were estimated before and after rooting. The rooting percentage and rooting degree were determined. A relatively high or moderate natural rooting ability without any treatment were shown by R. beggeriana ‘Polstjärnan’ in 63.8%–87.5% and by R. helenae ‘Semiplena’ in 41.3%–72.5% cuttings. IBA and NAA decreased the mean rooting percentage in ‘Polstjärnan’, but increased it for P4 cuttings in ‘Semiplena’. None of the preparations had any impact on the degree of rooting. The mean level of total soluble and reducing sugars in leaves and stems of cuttings before rooting was lower than that of after root formation. The preparations of plant origin positively affected rhizogenesis and sugar contents in plant tissues, but their effect depended on shoot's phenological phase and cultivar. Plant origin preparations may successfully replace those containing IBA or NAA. 相似文献