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71.
Growing pigs provided with ileocaecal re-entrant cannulae were fed three rations containing plant protein sources and two N-free rations. The crude protein and amino acid flow in the digestive tract as well as the apparent and true digestibility of the crude protein and the amino acids for the individual sections of the intestines are explained. It shows that relating the calculation of metabolic faecal amino acids to live weight results in more realistic values than relating it to feed intake.  相似文献   
72.
The amino acid composition in the chyme and faecel protein after feeding pigs with different diets is described. It is to be stated that chyme protein cannot necessarily be considered homogenous. Faecal protein shows less considerable variations in its composition and deviates distinctly from the composition of the faecal bacteria. The quota of bacterial crude protein was calculated according to the content of 2,6 diamino pimelic acid. In the chyme protein (end of the ileum) it amounted to approximately 30% and in the faecal protein to approximately 50%.  相似文献   
73.
BACKGROUND: Pericardial effusion (PE) in dogs most often is associated with neoplasia or idiopathic pericarditis, and frequently causes cardiac tamponade. Studies of PE in the cat are limited. HYPOTHESIS: Congestive heart failure (CHF) is the most common cause of PE in the cat. ANIMALS: All cats diagnosed with PE on echocardiographic examination at the Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania (MJR-VHUP) from 2000 to 2005. METHODS: The clinical and pathologic findings in 146 cats with PE were reviewed. Records were examined retrospectively to identify additional underlying conditions. Follow-up status and cause of death were determined by review of the medical records or phone interviews with the owners. RESULTS: The most common cause of PE in this study was CHF (75%). Biochemical abnormalities were uncommon, but aspartate aminotransferase (AST) activity frequently was increased (85%). Follow-up information was available on 108 cats (74%). Median survival time (MST) was 144 days for cats that were not euthanized within 24 hours (n = 85). The MST of cats with heart failure was 41 days, whereas the MST of cats without heart failure was 361 days, when those euthanized within 24 hours were excluded. CONCLUSIONS: Survival time of cats with heart failure in this study was significantly shorter than previously reported, and significantly shorter than in cats without heart failure as a cause of PE.  相似文献   
74.
Due to its high vapor pressure and low boiling point, desflurane requires a specially designed, electronically controlled, temperature and pressure compensated vaporizer to regulate agent delivery to the anesthetic circuit. However, if the vapor pressure and boiling point were decreased, desflurane could be used in any conventional variable bypass vaporizer. Raoult's Law states that the vapor pressure of a liquid is proportional to its molar fraction in a solution. Accordingly, propylene glycol was used as a solvent for desflurane, and the physical characteristics of this mixture were evaluated at various molar concentrations and temperatures. Desflurane boiling point increased and vapor pressure decreased as a nonlinear function of dilution, but these changes were less than predicted by Raoult's Law. Using a circle system with a breathing bag attached at the patient end and a mechanical ventilator to simulate respiration, an in‐circuit, nonprecision vaporizer containing 40% desflurane and 60% propylene glycol achieved a 11.5 ± 1.0% (mean ± SD) circuit desflurane concentration with a 5.2 ± 0.4 (0 = off, 10 = maximum) vaporizer setting. This experiment was repeated with a dog attached to the breathing circuit under spontaneous ventilation with a fresh gas flow of 0.5 L min–1. Anesthesia was maintained for over two hours at a mean vaporizer setting of 6.2 ± 0.4, yielding mean inspired and end‐tidal desflurane concentrations of 8.7 ± 0.5% and 7.9 ± 0.7%, respectively. Within 5 minutes after cessation of anesthesia, the dog was awake, extubated and standing. In clinical practice, propylene glycol may not prove an ideal solvent for desflurane due to its instability in solution and substantial positive deviation from Raoult's Law. However, rather than alter the vaporizer to suit physical properties of anesthetic agents, this study demonstrates that it may also be possible to alter anesthetic agents to suit physical properties of the vaporizer.  相似文献   
75.
A laboratory experiment with larval cod fed natural zooplankton and enriched rotifers was carried out to investigate the effects of feed type on fatty acid (FA) and lipid composition. A divergence in FA composition was observed within a week of feeding on respective diets, and subsequent transfers of larvae from one feeding regime to the other also confirmed a rapid change in FA composition towards that of the newly provided feed source. The rapid change in FA composition after switching diet is in part expected to be due to the high growth and tissue turnover of cod larvae during the early life stages and provides an opportunity to assess recent feeding history by means of FA analysis. The FA contents also varied between the main analysed lipid classes, with relatively higher eicosapentaenoic acid levels in neutral lipids than in polar lipid classes. Although zooplankton contained notably more polar lipids and less neutral lipids than enriched rotifers, the relative amounts of polar and neutral lipids in larvae from respective prey groups were similar, signifying that the larval composition only partly reflects what they have been eating. Still, the FA composition of the previous diet was still discernible in larvae after 1–2 weeks of transfer to a new diet or after weaning to a formulated feed. The potential long‐term effects of these nutritional differences are discussed.  相似文献   
76.
TriN 2755 is an alkylating antineoplastic agent for intravenous (IV) use, carrying the triazene group as the cytotoxic principal. Using a standard 3 + 3 design, a phase I study was performed in tumour bearing dogs to determine the maximum tolerated dose (MTD), the dose limiting toxicity (DLT), and pharmacokinetic (PK) profile of TriN 2755. Thirty dogs were included in the study. TriN 2755 was administered over 20 min on two consecutive weeks per month for a total of three cycles. The starting dose was 25 mg kg?1 and the MTD was 74.6 mg kg?1. Three dogs experienced DLT, which was characterized by gastrointestinal adverse events. The PKs of TriN 2755 and its main metabolites in plasma and sputum are described in a two‐compartment model. The response rate for 19 of 30 dogs was 47.3% (six partial remission, three stable disease) and the median progression‐free interval (PFI) for the responders was 47 days (range: 21–450 days).  相似文献   
77.

Purpose

Copper (Cu) contamination has been increasing in land ecosystems. Biochars (BCs) and arbuscular mycorrhizal fungi (AMF) are known to bind metals, and metallophyte can remove metals from soils. Will BC in combination with AMF contain the Cu uptake by a metallophyte growing in a metal-contaminated soil? The objective of this study was to investigate the effects of BCs on the Cu immobilization and over soil microbial communities in a metal-contaminated soil in the presence of AMF and metallophyte.

Materials and methods

Two BCs were produced from chicken manure (CMB) and oat hull (OHB). A Cu-contaminated sandy soil (338 mg kg?1) was incubated with CMB and OHB (0, 1, and 5 % w/w) for 2 weeks. Metallophyte Oenothera picensis was grown in pots (500 mL) containing the incubated soils in a controlled greenhouse for 6 months. A number of analyses were conducted after the harvest. These include plant biomass weight, microbial basal respiration, and dehydrogenase activity (DHA), AMF root colonization, spore number, and glomalin production; changes in fungal and bacterial communities, Cu fractions in soil phases, and Cu uptake in plant tissues.

Results and discussion

The BCs increased the soil pH, decreased easily exchangeable fraction of Cu, and increased organic matter and residual fraction of Cu. The BCs provided favorable habitat for microorganisms, thereby increasing basal respiration. The CMB increased DHA by ~62 and ~574 %, respectively, for the low and high doses. Similarly, the OHB increased soil microbial activity by ~68 and ~72 %, respectively, for the low and high doses. AMF root colonization, spore number, and total glomalin-related soil protein (GRSP) production increased by ~3, ~2, and ~3 times, respectively, in soils treated with 1 % OHB. Despite being a metalophyte, O. picensis could not uptake Cu efficiently. Root and shoot Cu concentrations decreased or changed insignificantly in most BC treatments.

Conclusions

The results show that the BCs decreased bioavailable Cu, decreased Cu uptake by O. picensis, improved habitat for microorganisms, and enhanced plant growth in Cu-contaminated soil. This suggests that biochars may be utilized to remediate Cu-contaminated soils.
  相似文献   
78.
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   
79.
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   
80.
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