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81.
The aim of this study was to evaluate the correlation between the cerebral state index (CSI) and the estimated propofol plasma concentrations in dogs during induction of anaesthesia. Fifteen healthy dogs undergoing scheduled routine surgical procedures were enrolled in this study. Target controlled infusion (TCI) software, based on the pharmacokinetic model for propofol, was used to control the syringe pump and to estimate plasma propofol concentrations (PropCp) and the CSI values every five-seconds. Three electrodes placed in the centre of the forehead, on the left side of the forehead and on the left mastoid were used to collect the electroencephalographic (EEG) signal converted by the cerebral state monitor into the CSI. The cerebral electrical changes induced by increasing propofol concentrations appear to be detected by CSI monitoring in dogs. The negative correlation between CSI and PropCp demonstrates that the CSI could be used to assess electrical brain activity in dogs during the induction of anaesthesia with propofol.  相似文献   
82.
Objective: To determine the cardiovascular effects of desflurane in dogs following acute hemorrhage. Design: Experimental study. Animals: Eight mix breed dogs. Interventions: Hemorrhage was induced by withdrawal of blood until mean arterial pressure (MAP) dropped to 60 mmHg in conscious dogs. Blood pressure was maintained at 60 mmHg for 1 hour by further removal or replacement of blood. Desflurane was delivered by facemask until endotracheal intubation could be performed and a desflurane expiratory end‐tidal concentration of 10.5 V% was maintained. Measurements and main results: Systolic, diastolic, and mean arterial blood pressure (SAP, DAP and MAP), central venous pressure (CVP), cardiac output (CO), stroke volume (SV), cardiac index (CI), systemic vascular resistance (SVR), heart rate (HR), respiratory rate (RR), partial pressure of carbon dioxide in arterial blood (PaCO2), and arterial pH were recorded before and 60 minutes after hemorrhage, and 5, 15, 30, 45 and 60 minutes after intubation. Sixty minutes after hemorrhage, SAP, DAP, MAP, CVP, CO, CI, SV, PaCO2, and arterial pH decreased, and HR and RR increased when compared with baselines values. Immediately after intubation, MAP and arterial pH decreased, and PaCO2 increased. Fifteen minutes after intubation SAP, DAP, MAP, arterial pH, and SVR decreased. At 30 and 45 minutes, MAP and DAP remained decreased and PaCO2 increased, compared with values measured after hemorrhage. Arterial pH increased after 30 minutes of desflurane administration compared with values measured 5 minutes after intubation. Conclusions: Desflurane induced significant changes in blood pressure and arterial pH when administered to dogs following acute hemorrhage.  相似文献   
83.
The addition of organic acids to diet of young pigs has been shown to improve their zootechnical performance. The aim of these experiments was to evaluate the effects of dietary supplementation with BA (VevoVitall®) on the zootechnical performance (DWG and FCR), the gastrointestinal microflora of the weaner piglet and to determine the effects on the ileal digestibility. For the zootechnical and microbiological evaluations 124 28-day-old piglets were used. During 32 days half of them were fed a maize–soybean meal based diet and the other half this diet supplemented with 0.5% BA. At the end of the study the stomach and caecum contents were sampled from 12 animals of each group for microbiological determinations. For the ileal digestibility study 60-day-old ileo-rectal anastomosed piglets were used and fed alternatively the same diet supplemented or not with 0.5% BA. Digestibilities of total nitrogen (N), energy (E) and amino acids (AA) were evaluated.

The BA group had significantly higher DWG and FCR than that of the control group. BA reduced almost all the determined bacterial populations of the gastrointestinal tract of the piglet. The reductions were significant for gastric lactic acid bacteria and caecal E. coli. The ileal digestibility of E and AA was numerically improved and that of N significantly increased in the BA group.  相似文献   

84.
Phosphorus (P) from plant-derived feedstuffs is mainly in the form of phytic-P, which has a very low bioavailability in monogastric animals. The non-absorbed phytic-P may contribute to P pollution, reduce mineral bioavailability and might reduce protein digestibility. The aim of this study was to evaluate the effects of the recommended levels of Ronozyme® P CT 5000 (750 U/kg — RP) and Natuphos® 5000 (500 U/kg — Nat) on the ileal apparent digestibility of total P, phytates (Phy), calcium (Ca), total nitrogen (N), energy, and amino acids (AA) in 60-day-old ileo-rectal anastomosed pigs. In a double Latin square design they were fed ad libitum either a maize–rapeseed meal based diet or this diet supplemented with RP or with Nat. RP and Nat increased the digestibility of P by 148% and 162%, of Phy by 84% and 76%, and of Ca by 44% and 50%, respectively. The total N digestibility was increased by 4% with RP (P < 0.01) and by 1% with Nat. A numerically increase of the digestibility of most of the AA was observed for Nat and of all AA for RP. Threonine digestibility was significantly increased by RP (P < 0.05). The results of this study indicate that phytases are able to increase the availability of proteins.  相似文献   
85.
In the Mediterranean evergreen oak woodlands of southern Portugal, the main tree species are Quercus ilex ssp. rotundifolia Lam. (holm oak) and Quercus suber L. (cork oak). We studied a savannah-type woodland where these species coexist, with the aim of better understanding the mechanisms of tree adaptation to seasonal drought. In both species, seasonal variations in transpiration and predawn leaf water potential showed a maximum in spring followed by a decline through the rainless summer and a recovery with autumn rainfall. Although the observed decrease in predawn leaf water potential in summer indicates soil water depletion, trees maintained transpiration rates above 0.7 mm day(-1) during the summer drought. By that time, more than 70% of the transpired water was being taken from groundwater sources. The daily fluctuations in soil water content suggest that some root uptake of groundwater was mediated through the upper soil layers by hydraulic lift. During the dry season, Q. ilex maintained higher predawn leaf water potentials, canopy conductances and transpiration rates than Q. suber. The higher water status of Q. ilex was likely associated with their deeper root systems compared with Q. suber. Whole-tree hydraulic conductance and minimum midday leaf water potential were lower in Q. ilex, indicating that Q. ilex was more tolerant to drought than Q. suber. Overall, Q. ilex seemed to have more effective drought avoidance and drought tolerance mechanisms than Q. suber.  相似文献   
86.
Solanum americanum Mill. is a weed that occurs with a number of crops, and it is known for its high seed production and its staggered germination. The objective of this work was to evaluate the germination behavior of S. americanum seeds under the influence of chemical and environmental factors. In the laboratory, we tested the effect on germination of (i) constant and alternating temperatures, (ii) seed washing, (iii) exposure time and concentration of chemical treatments and (iv) seeding depth and soil covered with plant residue on seedling emergence. The variables analyzed were germination percentage, germination rate index, seedling emergence and length of the seedlings. The results indicated that alternating temperatures are the main way to promote germination of S. americanum; however, chemical treatments can help to increase the germination percentage and rate index. There was no increase in germination with seed washing, with the exception of KNO3 application. A GA3 concentration of 0.84 g L?1 and an exposure time of 21.22 h in 0.2% of KNO3 promoted the highest germination of S. americanum. Germination occurs when seeds remain on the soil surface and are not covered by crop residue.  相似文献   
87.
Ceratocystis wilt caused by Ceratocystis fimbriata is currently one of the most important diseases affecting Eucalyptus in Brazil. This disease is controlled by planting resistant clones; however, possible variability in the pathogen population may compromise the selection of resistant genotypes. Therefore, this study aimed to evaluate the aggressiveness of C. fimbriata isolates obtained from Eucalyptus spp, as well as their cultural characteristics and genetic variation of their ITS rDNA gene region. We found a significant isolate × clone interaction, with the isolate RM35 being the most aggressive and presenting a broader spectrum of aggressiveness, causing greater xylem discoloration on a larger number of clones. This isolate is the most suitable for artificial inoculations focusing on the selection of resistant materials. Clones CLR‐236 and CLR‐212 were identified as the most resistant and clones CLR‐223 and CLR‐240 as the most susceptible and those that are recommended as reliable comparators in artificial inoculations. All isolates were morphologically similar and differed from C. fimbriata from sweet potato by the formation of a wide mouth endoconidiophore that produces doliform endoconidia. According to the culture media and temperature applied, the most favourable conditions for mycelial growth were observed using malt extract agar (MEA) and temperatures ranging from 24 to 26°C. There was no correlation between sporulation and aggressiveness. Great variation in ITS sequences was observed, and a total of five ITS genotypes were identified among the ten isolates tested.  相似文献   
88.
89.
The administration of fish oils is known to cause changes in several reproductive parameters of domestic animals. The ingestion of polyunsaturated fatty acids (PUFAs) of the omega-3 family, such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), has been described and correlated with changes in the semen quality, testosterone levels and male fertility. Nevertheless, few studies monitored and registered effects after ceasing supplementation. In the present study, we monitored the Doppler velocimetric and ultrasonographic parameters of nine dogs' testis for 90 days (D90) checking the effect of salmon oil supplementation, and monitoring continued for 60 days more, after ceasing supplementation (D150). Ultrasonographic evaluations comprised determining the Doppler velocimetric parameters, testicular and epididymal volume, and testicular echotexture. Peak systolic velocity (PSV) as well as final diastolic velocity (EDV) in the supratesticular arteries (STA), and marginal artery (MA) increased during the period of treatment and kept that level up to D150. There was no difference between the fish-oil supplementation period and the unsupplemented one regarding the testicular and epididymal volume and echogenicity and heterogeneity characteristics. A negative correlation was found between heterogeneity of testis and sperm production (r = −.41, p = .008). Doppler velocimetry indices were affected by the supplementation, leading to an increase in testicular blood flow.  相似文献   
90.
OBJECTIVE: To evaluate the reliability and validity of a six-item food security scale when self-administered by adolescents. DESIGN: Cross-sectional questionnaire survey including the six-item food security measure, socio-economic variables and a food-frequency questionnaire. SETTING: Representative sample of 29 schools in Trinidad. SUBJECTS: In total 1903 students aged approximately 16 years. RESULTS: Item affirmatives ranged from 514 (27%) for the 'balanced meal' item to 128 (7%) for the 'skipped or cut meals often' item and 141 (7%) for the 'hungry' item. Item-score correlations ranged from 0.444 to 0.580. Cronbach's alpha was 0.77. Relative item severities from the Rasch model ranged from -1.622 (standard error 0.043) for the 'balanced meal' item to 1.103 (0.068) for the 'skipped or cut meals often' item and 0.944 (0.062) for the 'hungry' item. The 'hungry' item gave a slightly lower relative severity in boys than girls. Food insecurity was associated with household overcrowding (adjusted odds ratio comparing highest and lowest quartiles 2.61, 95% confidence interval 1.75 to 3.91), lack of pipe-borne water in the home, low paternal education or paternal unemployment. After adjusting for socio-economic variables, food insecurity was associated with less frequent consumption of fruit (0.75, 0.60 to 0.94) or fish (0.72, 0.58 to 0.88) but more frequent consumption of biscuits or cakes (1.47, 1.02 to 2.11). CONCLUSIONS: The food security scale provides a valid, reliable measure in adolescents, although young people report being hungry but not eating relatively more frequently than adults. Food-insecure adolescents have low socio-economic position and may eat less healthy diets.  相似文献   
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