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11.
OBJECTIVE: To determine whether the bispectral index (BIS) can be used as an indicator of degree of CNS depression in isoflurane-anesthetized horses. ANIMALS: 10 Standardbred and 6 Norwegian cold-blooded trotter stallions admitted for routine castration. PROCEDURE: A 2-channel referential electrode configuration was used to record EEG for calculation of BIS by the EEG monitor. The BIS was calculated before (awake) and after (sedated) administration of detomidine (0.01 mg/kg of body weight, IV) and butorphanol (0.01 mg/kg, IV). Anesthesia was induced with ketamine hydrochloride (2.5 mg/kg, IV) and diazepam (0.04 mg/kg, IV) and maintained with isoflurane delivered in oxygen. The BIS was calculated after 30 minutes of equilibration at an end-tidal isoflurane concentration of 1.4% (n = 8) or 1.9% (8) and recorded continuously during surgery. RESULTS: Bispectral index was significantly less in sedated and anesthetized horses, compared with awake horses. However, BIS was not significantly different between sedated and anesthetized horses. Mean BIS in horses anesthetized at 1.9% isoflurane was significantly greater, compared with horses anesthetized at an end-tidal concentration of 1.4%. Four horses in the 1.4% group moved during surgery, and BIS increased immediately prior to movement in 2 of these horses. CONCLUSIONS AND CLINICAL RELEVANCE: BIS is not a precise indicator of degree of CNS depression in isoflurane-anesthetized horses. Thus, determination of BIS may not be a useful technique for monitoring anesthetic depth in isoflurane-anesthetized horses. 相似文献
12.
13.
Microbial and microfaunal community structure in cropping systems with genetically modified plants 总被引:3,自引:3,他引:3
Bryan S. Griffiths Sandra Caul Jacqueline Thompson A. Nicholas E. Birch Jrme Cortet Mathias N. Andersen Paul Henning Krogh 《Pedobiologia》2007,51(3):195-ECOGEN
Soils from field sites at Foulum (DK), Narbons (FR) and Varois (FR) planted with genetically modified maize expressing either the insecticidal Bacillus thuringiensis protein (Bt) or herbicide tolerance (HT), as described elsewhere in this volume, were analysed for nematodes, protozoa and microbial community structure. These analyses were mirrored in single-species testing and in mesocosm experiments, and were coordinated with field samples taken for microarthropods, enchytraeids and earthworms so allowing for cross-comparison and a better understanding of the results observed in the field. Over the first 2 years of the field experiments (in 2002 and 2003), the effect of Bt-maize was within the normal variation expected in these agricultural systems. Sampling in 2004 and 2005 was expanded to include the effects of tillage (i.e. reduced tillage versus conventional tillage) and also the use of HT-maize. Tillage had major effects regardless of soil type (Varois or Foulum), with reduced-tillage plots having a greater abundance of microfauna and a different microbial community structure (measured both by phospholipid fatty-acid analysis (PLFA) and by community-level physiological profiling (CLPP)) from conventionally tilled plots. Grass, as a contrasting cropping system to maize, also had an effect regardless of soil type and resulted in greater microfaunal abundance and an altered microbial community structure. Differences in crop management, which for the Bt-maize was removal of the insecticide used to control European corn borer and for HT-maize was a change in herbicide formulation, were only tested at single sites. There were differences in microbial community structure (CLPP but not PLFA) and sporadic increases in protozoan abundance under the Bt-crop management. The HT-maize cropping system, which covered a shorter period and only one site, showed little change from the conventional system other than an altered microbial community structure (as measured by PLFA only) at the final harvest. The Bt-trait had a minimal impact, with fewer amoebae at Foulum in May 2003, fewer nematodes at Foulum in May 2004 but more protozoa at Varois in October 2002 and an altered microbial community structure (PLFA) at Foulum in August 2005. These were not persistent effects and could not be distinguished from varietal effects. Based on the field evaluations of microfauna and microorganisms, we conclude that there were no soil ecological consequences for these communities associated with the use of Bt- or HT-maize in place of conventional varieties. Other land management options, such as tillage, crop type and pest management regime, had significantly larger effects on the biology of the soil than the type of maize grown. 相似文献
14.
Henning Nordmeyer 《植物养料与土壤学杂志》1994,157(4):283-288
Soil variability and pesticide behaviour The spatial variability of selected soil characteristics (organic carbon, particle size), pesticide adsorption and leaching was estimated for an agricultural location. Variograms were calculated to describe the spatial dependence of data. All parameters showed a nearly isotropic behaviour. According to variograms a kriging interpolation was done and the spatial variability of parameters was estimated. Leaching of terbuthylazine was calculated (model PRZM) with regard to soil variability and adsorption pattern (Kd-values). Leaching depth in the winter season varied between 10 and 22 cm depending strictly on soil characteristics. 相似文献
15.
Anema SG Lee SK Lowe EK Klostermeyer H 《Journal of agricultural and food chemistry》2004,52(2):337-343
Reconstituted skim milk was adjusted to pH values between 6.5 and 7.1 and heated (90 degrees C) for up to 30 min. The skim milk samples were then readjusted to pH 6.7. Acid gels prepared from heated milk had markedly higher G ' values, a reduced gelation time, and an increased gelation pH than those prepared from unheated milk. An increased pH at heating decreased the gelation time, increased the gelation pH, and increased the final G ' of acid set gels prepared from the heated milk samples. There were only small differences in the level of whey protein denaturation in the samples at different pH values, and these differences could not account for the differences in the G ' of the acid gels. The levels of denatured whey protein associated with the casein micelles decreased and the levels of soluble denatured whey proteins increased as the pH at heating was increased. The results indicated that the soluble denatured whey proteins had a greater effect on the final G ' of the acid gels than the denatured whey proteins associated with the casein micelles. 相似文献
16.
Henning Nordmeyer 《Precision Agriculture》2006,7(3):219-231
Site-specific weed control in winter cereals was performed on the same fields every year over a 5-year period (1999–2003). The most common weeds (Apera spica-venti, Galium aparine, Veronica hederifolia, Viola arvensis) were counted by species, at grid points which were georeferenced and the data were analysed spatially. For weed control, weeds were grouped into three classes: grass, broad-leaved weeds (without Galium aparine), and Galium aparine. Based on weed distribution maps generated by the spatial analyses, herbicide application maps were created and site-specific herbicide application was carried out for grouped and or single weed species. This resulted in a significant reduction in herbicide use. Averaging the results for all fields and years, the total field area treated with herbicides was 39% for grass weeds, 44% for broad-leaved weeds (without Galium aparine) and 49% for Galium aparine. Therefore, site-specific weed control has the potential to reduce herbicide use compared to broadcast application, thus giving environmental and economic benefits. 相似文献
17.
Lycopene accumulation induced by 2-(4-chlorophenylthio)-triethylamine hydrochloride 总被引:11,自引:0,他引:11
After fruits, roots, or the mycelium of certain plants were treated with 2-(4-chlorophenylthio)-triethylamine hydrochloride, lycopene was detected in the tissue. This is the first known success in causing lycopene to accumulate in a wide range of carotenogenic tissues that normally do not accumulate the pigment at some stage of development. The response should be of value in the study of carotenoid biosynthetic pathways and gene control mechanisms. 相似文献
18.
A.G. Pillai Medha S. Naik G.A. Momin P.S.P. Rao P.D. Safai K. Ali Henning Rodhe Lennart Granat 《Water, air, and soil pollution》2001,130(1-4):475-480
Rain water and dustfall deposition samples were collected at Pune, an urban site (1992–98) and at Sinhagad, a rural site (1992–94). The samples were collected with wet-only and bulk collectors at Pune and with bulk collector at Sinhagad. The samples were analyzed for major ions, pH and conductivity. The study showed that the rain water at both places is alkaline (pH > 5.6). The average pH at Pune was 6.1. Neutralising components, indicated by Ca and non sea salt (nss) Mg have higher concentrations than the acidifying components SO4 and NO3. The wet deposition fluxes of all the ionic components were higher than the dustfall fluxes. Relative contribution from dustfall was largest for K, Ca, Mg and NO3. Dustfall was greater at Pune, compared to Sinhagad for all components and up to double for Ca. 相似文献
19.
20.
A Daugschies M Rommel T Schnieder M Henning E Kallweit 《Veterinary parasitology》1988,27(3-4):231-237
Ten halothane-positive pigs (stress sensitive, group A) and ten halothane-negative pigs (stress insensitive, Group C) with a mean body weight of 36 kg were each inoculated orally with 50,000 sporocysts of Sarcocystis miescheriana. Twelve halthane-positive pigs (Group B) and ten halothane-negative pigs (Group D) served as non-infected controls. Thirteen weeks post infection (p.i.) the lean: fat ratios of the pigs of the infected groups A and C were lower (A, 1:0.41 +/- 0.09; C, 1:0.50 +/- 0.10) than those of the pigs of the non-infected groups B and D (B, 1:0.50 +/- 0.08; D, 1:0.55 +/- 0.08). The back-fat thickness, the fat thickness 'A' and the fat thickness 'B' were thinner in infected pigs than in non-infected pigs. The difference in Lendenst?rkespeckquotient (Loin Fat Thickness Quotient) (LSQ) between infected and non-infected pigs was not statistically significant. The values of the water-holding capacity were lower in infected pigs than in non-infected pigs, the difference being statistically significant only in the halothane-negative groups (C, 0.45 +/- 0.02; D, 0.48 +/- 0.04). The water-absorbing capacity was significantly higher in the infected groups (A, 5.92 +/- 3.99%; B, 2.26 +/- 1.08%; C, 8.96 +/- 2.90%; D, 4.97 +/- 2.51%). In conclusion, it can be said that there was a slight tendency towards a better carcass quality and a better water-binding capacity in infected pigs, although this was combined with reduced growth rates. 相似文献