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451.
Anemon I is a new monitoring system that can be used to evaluate autonomic nervous system reactivity in real time by showing a simple, easily interpretated quantitative index (0–200), the Anemon Index (AI) ( Junke et al. 2000 ). This study used the AI to evaluate the quality of analgesia during sevoflurane and fentanyl anaesthesia in pigs. Six healthy pigs, weighing 24.76 ± 3.40 kg, were induced to anaesthesia with 5% sevoflurane (SEVO) in 5 L minute?1 oxygen. After endotracheal intubation SEVO was given at 1 MAC (2.66%) in 3 L minute?1 oxygen. Fentanyl was infused IV at 50 µg kg?1 hour?1 for the first 30 minutes of anaesthesia, discontinued for 30 minutes, and then infused at 100 µg kg?1 hour?1 for another 30 minutes. Three mechanical noxious stimuli (needle prick, pin‐prick and pressure on the abdomen) were applied for 15 seconds at 30, 60 and 90 minutes. The AI, ECG, invasive mean arterial blood pressure (MAP), heart rate (HR), SpO2 by pulse oximetry, tidal volume, Fe′sevo , Fe ′CO2 and respiratory rate were recorded before induction (baseline), after induction, after intubation and extubation, and before and during noxious stimulation at 30, 60 and 90 minutes. Recovery times were recorded. Statistically significant differences were determined by anova . Spearman rank‐correlation was used to evaluate the relationship between AI and hemodynamic variables. A p‐value of < 0.05 was considered significant. A significant (p < 0.01) decrease in AI was recorded after anaesthetic induction, from 82.3 ± 21.1 to 52.7 ± 20.3. After intubation, AI increased slightly, but not significantly, to 71.7 ± 27.1. A significant (p < 0.05) increase of AI occurred after extubation. Nociceptive stimuli did not have any measurable effect either on AI or on recorded cardiovascular variables. There was no movement, respiratory changes, or any other visible response to noxious stimulation. The AI did not change significantly with the different doses of fentanyl. Respiratory depression and apnoea were seen in all animals during the fentanyl infusion; therefore, pigs received intermittent positive pressure ventilation. Anaesthesia with sevoflurane and fentanyl resulted in a significant (p < 0.001) decrease in MAP. Heart rate did not change significantly. There was no correlation between AI and cardiovascular variables (HR and MAP). Endotracheal intubation caused an increase and extubation a greater significant increase in the AI. This suggests that intubation and extubation may represent stressful events during general anaesthesia, although further studies are needed to validate the use of the AI in pigs. Sevoflurane anesthetic induction may not prevent the sympathetic stimulus caused by endotracheal intubation in pigs, as indicated by the increased AI values.  相似文献   
452.
<正>1肉鸡饲料中的维生素需要量1.1维生素之间及其与其它营养素的复杂相互作用维生素并非一种单独的营养素,不同维生素之间存在各种各样的相互作用。例如,脂溶性维生素互相竞争小肠吸收,其中一种维生素过量可能导致其它维生素缺乏,使用高水平的维生素A时表现尤  相似文献   
453.
Fourteen dogs with enlarged gallbladders and immobile stellate or finely striated bile patterns on ultrasound are described. Smaller breeds and older dogs were overrepresented, with 4/14 Cocker Spaniels. Most dogs presented for nonspecific clinical signs such as vomiting, anorexia and lethargy. Abdominal pain, icterus and hyperthermia were the most common findings on physical examination. All dogs except one had serum elevation of total bilirubin and/or alkaline phosphatase, alanine aminotransferase and gamma glutamyl transferase. All dogs were diagnosed with a gallbladder mucocele upon histologic and/or macroscopic evaluation. Ultrasonographically, mucoceles are characterized by the appearance of the stellate or finely striated bile patterns and differ from biliary sludge by the absence of gravity dependent bile movement. On ultrasound, gallbladder wall thickness and wall appearance were variable and nonspecific. The cystic or common bile duct were normal sized in 5 dogs although all 5 had evidence of biliary obstruction at surgery or necropsy. Loss of gallbladder wall integrity and/or gallbladder rupture were present in 50% of the dogs, all located in the fundus. Gallbladder wall discontinuity on ultrasound indicated rupture whereas neither bile patterns predicted the likelihood of gallbladder rupture. Pericholecystic hyperechoic fat or fluid were suggestive of but not diagnostic for a gallbladder rupture. Cholecystectomy appears to be an appropriate treatment for mucoceles, if not to treat a gallbladder rupture, at least in most dogs to prevent it since gallbladder wall necrosis was identified by histology in 9 of 10 dogs. Mucosal hyperplasia was present in all gallbladders examined histologically. Positive aerobic bacterial culture was obtained from bile in 6 of 9 dogs. Cholecystitis was diagnosed histologically in 5 dogs and 4 dogs had signs of gallbladder infection solely upon bacterial bile culture. Gallbladder infection was not present with all the mucoceles suggesting that biliary stasis and mucosal hyperplasia may be the primary factors involved in mucocele formation. Based on the results of our study, we suggest two alternate courses of action in the presence of a distended gallbladder with an immobile ultrasonographic stellate or finely striated bile pattern: a cholecystectomy when clinical or biochemical signs of hepatobiliary disease are present or a medical treatment (antibiotics and choleretics) and patient monitoring by follow-up ultrasound examinations when the patient does not have clinical or biochemical abnormalities. An aerobic bile culture should be obtained in all patients, by ultrasound-guided fine needle aspirate or at surgery.  相似文献   
454.
Most chaotic mixing experiments have been restricted to two-dimensional, time-periodic flows, and this has shaped advances in theory as well. A prototypical, bounded, three-dimensional flow with a moderate Reynolds number is presented; this system lends itself to detailed experimental observation and allows for high-precision computational inspection. The flow structure, captured by means of cuts with a laser sheet (experimental Poincare section), was visualized with the use of continuously injected fluorescent dye streams and revealed detailed chaotic structures with high-period islands.  相似文献   
455.
Sablefish Anoplopoma fimbria is a piscivorous fish that is highly desirable as food. To ascertain the relationship of dietary protein, lipid and carbohydrate, eleven diets containing fishmeal, fish oil and wheat flour as test ingredients at different levels were formulated. The levels were chosen according to mixture experiment methodology, which varies the proportion of each test ingredient, while keeping their sum constant across all diets. The range of levels used in the test diets were as follows: fishmeal 430–600 g kg?1, fish oil 100–270 g kg?1 and wheat flour 30–200 g kg?1. The sum of the test ingredients accounted for 900 g kg?1 of all diets, with the remaining 100 g kg?1 accounting for mineral and vitamin premix, binders, attractant, etc. Each diet, plus a commercial feed, was fed to three tanks of juvenile sablefish by hand twice daily for 11 weeks, using a completely random design. It was found that growth and feed efficiency were maximized by the highest dietary inclusion level of fish oil and fishmeal, corresponding to the lowest wheat flour level, that is 600 g kg?1 fishmeal, 270 g kg?1 fish oil and 30 g kg?1 wheat flour.  相似文献   
456.
Spores from 3 aflatoxigenic strains were applied to the surface of dried figs, pineapple slices, apricots, and raisins. Half of the samples of each foodstuff was autoclaved (cooked) before inoculation. All 3 strains produced some toxin but not in all of the foodstuffs. No aflatoxins were found in any of the raisin cultures. The overall potential for toxin production in the dried fruit was apricot greater than fig greater than pineapple greater than raisin. Among the cooked substrates, the order was apricot greater than pineapple greater than fig=raisin. For the raw dried fruits, the ranking was fig greater than pineapple greater than apricot greater than or equal to raisin. Pineapple was considered the best broad spectrum substrate of the foodstuffs evaluated in the study.  相似文献   
457.
We consider various methods for estimating age composition from length and age samples. The standard age–length key (ALK) approach does not use information from the length frequency distribution, so we develop likelihood-based methods with and without seasonality, growth curves, and cohort-specific growth effects.Asymptotic variances of the estimated age proportions are derived and converted into ‘equivalent sample size’, i.e. the sample size that would achieve the same variance if only age data were collected at random. This is used to compare and evaluate the information obtained from various models using likelihood and from ALK. The methodology is illustrated by analysing a large data set on Southern Bluefin Tuna Thunnus maccoyii. For younger fish, there are considerable gains (in equivalent sample size) over ALK from using likelihood estimation, and further gains from allowing for within-season growth. Sampling designs can improve the estimation of age composition of targeted older age ranges.  相似文献   
458.
Comment on Butterworth, Cubitt, and McKinley (2008)   总被引:1,自引:1,他引:0  
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