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81.
The effect of various combinations of vitamins C and E on immune response and disease resistance was investigated in rainbow trout, Oncorhynchus mykiss (Walbaum). The following combinations of vitamins were included in the diet (C/E): 0/0, 0/800, 2000/0, 30/30, 30/800, 2000/30, 2000/800. Liver ascorbic acid and alpha‐tocopherol contents reflected the dietary treatments well. Complement levels showed no significant differences. The combination of the high dietary doses of vitamins C and E significantly stimulated lymphoproliferation induced by Concanavalin A when compared with fish fed a low level of both vitamins, but also when compared with fish fed a low level of vitamin C and a high level of vitamin E. The highest macrophage oxidative burst activity, measured by chemiluminescence, was found in fish receiving both vitamins at high levels. In the disease resistance experiments, the best survival rates in trout infected with viral haemorrhagic septicaemia virus were achieved with diets containing both vitamins at a high level, or at least one at a high and the other at a low level. Highest mortalities in fish infected with Yersinia ruckeri occurred in trout fed double‐deficient or double low diets. The best survival of fish exposed to Ichthyophthirius multifiliis was achieved with diets high in one and low in the other, or high in both vitamins. However, differences were not statistically significant in the parasite experiment.  相似文献   
82.
BackgroundLocal progression of intracranial tumors can be the consequence of insufficient radiation dose delivered. Dose increases in the brain must be made carefully so as not to risk debilitating adverse effects such as radiation necrosis.HypothesisA new protocol with 10 × 4 Gy + 11% physical dose increase limited to the macroscopic tumor volume results in a clinically better outcome compared to a 10 × 4 Gy protocol.AnimalsFifty‐seven client‐owned dogs with primary intracranial neoplasia.MethodsRandomized controlled trial. Twenty‐eight dogs were assigned to the control protocol (10 × 4 Gy) and 29 to the simultaneous integrated boost (SIB) protocol with 4.45 Gy dose increase. Treatment groups were compared for outcome and signs of toxicity.ResultsMild, transient acute or early‐delayed adverse radiation effects were observed in 5 dogs. Severe late adverse effects were not seen. Between the protocols, no significant differences were found for outcome (intention‐to‐treat analysis): overall time to progression (TTP) was 708 days (95% confidence interval (95% CI) [545,872]), in the control group it was 828 days (95% CI [401,1256]), and in the SIB group 627 days (95% CI [282,973]; P = .07). Median overall survival (OS) was 684 days (95% CI [516,853]), in the control group it was 724 days (95% CI [623,826]), and in the SIB group 557 days (95% CI [95,1020]; P = .47). None of the tested variables was prognostic in terms of outcome.Conclusion and Clinical ImportanceThe dose escalation used with an 11% physical dose increase did not result in better outcome.  相似文献   
83.
Changes in ACTH challenge test characteristics in dairy cows changing their physiological status at different lactational stages and different feeding levels were not investigated in terms of repeatability yet. In 23 multiparous Holstein cows (10 cows fed a sole fresh herbage diet without concentrate, 13 cows fed with concentrate), three ACTH challenge tests were performed: once during pregnancy shortly prior to drying off ( T1 ), and in week 3 ( T2 ) and 8 ( T3 ) after parturition. Test characteristics were correlated to performance and metabolic parameters: DMI, BW, energy balance (EB), plasma concentrations of free fatty acids (NEFA) and beta‐hydroxybutyrate (BHB). Basal plasma cortisol concentrations were higher at T1 compared with T2 and T3 (p < .05). The adrenal cortex sensitivity (expressed as total AUC (AUCt) of cortisol response after ACTH application) was lowest at T2 compared with T1 and T3 (p < .05). Ranking of the individual animals’ responses was not repeatable between time points of the ACTH tests. Enhancing the energy deficiency during early lactation by omission of concentrate did not affect baseline cortisol concentrations in plasma, but decreased peak height at T2 (p < .05). Baseline plasma cortisol concentrations were positively correlated with cortisol peak values after ACTH application, previous lactation performance, milk yield and BW (p < .05). The AUCt was positively correlated with baseline cortisol concentrations, EB and DMI. Cortisol release after ACTH injection was lower in animals with high plasma concentrations of NEFA, BHB and with higher contents of fat and free fatty acids in milk (p < .05). Cortisol peak height after ACTH administration was higher in cows with a more positive EB, higher DMI and lower plasma concentrations of NEFA and BHB. In summary, cortisol responses to ACTH challenges in this study were not repeatable in dairy cows changing their physiological status.  相似文献   
84.
The spatial pattern of Fusarium‐infected kernels and their mycotoxin contamination was studied in four wheat fields in Germany using geo‐referenced sampling grids (12–15 × 20–30 m, 28–30 samples per field) at harvest. For each sample, frequency of Fusarium‐infected kernels and spectrum of species were assessed microbiologically; mycotoxin contents were determined by HPLC‐MS/MS analysis. Spatial variability of pathogens and mycotoxins was analysed using various parameters including Spatial Analysis by Distance IndicEs (sadie® ). Microdochium majus, the most frequent head blight pathogen in 1998, was less frequent in 1999 and could not be detected in kernels from two fields in 2004. Fusarium avenaceum, F. graminearum and F. poae were the most frequent Fusarium species, with 7–8 species per field. The frequency of Fusarium‐infected kernels was 3–15% and the incidence of species showed considerable within‐field variability. Spatial patterns varied among Fusarium species as well as from field to field. Although pathogens and mycotoxin were often distributed randomly in the field, F. avenaceum, F. graminearum, F. poae, F. sporotrichioides, F. tricinctum and the mycotoxin moniliformin had an aggregated pattern in at least one field. Patterns are discussed in relation to spread of Fusarium species depending on inoculum sources, spore type, kind of dispersal, availability of susceptible host tissue and micro‐climate. Sampling of wheat fields for representative assessment of mycotoxins is complicated by random patterns of Fusarium‐infected kernels, especially where the frequency of infection is small.  相似文献   
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86.
The frequency of fish diseases diagnosed at the Fish Disease Laboratory at the University of Berne from 1979 to 1988 is presented. Parasitic infections have been found to be the most frequent diagnosis. Among noninfectious diseases poisonings were predominant. Six infectious diseases have been considered to be economically relevant. These diseases (according to their frequency: Gyrodactylosis, Costiosis, Ichthyophthiriosis, Viral Hemorrhagic Septicemia (VHS), Saprolegniosis and Furunculosis) were further analysed. Their incidence varies with season, species, origin and length of fish. Possible explanations for these findings are discussed.  相似文献   
87.
A captive Malayan tapir was observed to have inappetence, weight loss, signs of depression, mild dehydration and diar rhoea. Haematological and serum biochemical tests showed anaemia, hypoproteinaemia, hyperfibrinogenaemia and neu-trophilia with a left shift. Ultrasonic examination of the abdomen under anaesthesia revealed a well-encapsulated abscess. The abscess was marsupialised to the ventral body wall. Culture of the pus produced a mixed bacterial growth. Antimicrobial therapy was based on bacterial sensitivity results. Follow-up ultrasonic examinations showed resolution of the abscess. Ninety-one days after surgery the tapir began regurgitating food and water. An abscess originating from the stomach and occluding the lumen of the duodenum was identified at surgery. The abscess ruptured during surgical manipulations and the tapir was euthanased.  相似文献   
88.
M. Geibel  D. Treutter  N. Meier 《Euphytica》1990,45(3):229-235
Summary In order to prove cultivar identity of sour cherries the flavonoids of the bark were separated with highperformance liquid-chromatography. The quantitative results were compared using the multivariate discriminant analysis. With this method 103 groups could be separated. Supposed unknown cultivars could be found by the computer in 95% of the performed test calculations.  相似文献   
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