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121.
Since glyphosate has been used extensively for weed control in Swedish railway tracks, common horsetail (Equisetum arvense L), previously relatively rare, has become very common. Glyphosate, although effective against most other weeds found on railway tracks, gives poor control of E. arvense, so that heavy infestation with this weed is now common. Imazapyr (applied as a 250g AE litre(-1) SL, Arsenal) has controlled E. arvense, but is known to be very mobile. Adequate control of the weed requires application of > or = 4 litres ha(-1) of imazapyr SL but environmental factors preclude the use of > 2 litres ha(-1). A suitable strategy was found to be one application of imazapyr SL at 2 litres ha(-1) in each of two successive years but best weed control was obtained by supplementing imazapyr in the first year with glyphosate 360 g AE litre(-1) SL (RoundUp Bio) at 3 litres ha(-1).  相似文献   
122.
Insulin resistance has been detected in obese Morgan horses and it has been suggested that horses of this breed are predisposed to this condition. The objective of this study was to determine whether blood lipid, glucose, and insulin concentrations differed between Morgan horses and Thoroughbreds housed at the same facility. Fourteen Morgan horses (five mares, nine geldings) ranging in age from 4 to 14 years were compared with 21 Thoroughbreds (11 mares, 10 geldings; age range 7–20 years) from the same herd. A single blood sample was collected from each horse after grain was withheld overnight. Variables were compared between breed groups and breed-specific reference ranges were calculated. Triglyceride, cholesterol, nonesterified fatty acid, glucose, and insulin concentrations did not differ between breeds of horse in this study. This may be because horses included in this study did not suffer from obesity and were regularly exercised.  相似文献   
123.
(-)-Epicatechin conjugates with sulfur-containing moieties are strong free radical scavengers with cell-protecting activities, which may be in part modulated by their capacity to bind to biological membranes. We present here a study of the interaction of these conjugates with membrane models such as multilamellar vesicles and a phospholipid-coated silica column (immobilized artificial membrane), monitored by differential scanning calorimetry and high-performance liquid chromatography, respectively. The nonpolyphenolic moiety significantly influenced the membrane behavior of the whole molecules. Bulky and hydrophobic conjugates clearly interacted with the phospholipids and may have a tendency to penetrate into the hydrophobic core of the vesicles. In contrast, the smaller cationic 4beta-(2-aminoethylthio)epicatechin may be located at the outer interface of the lipid membrane. The outcomes from both experimental set-ups were in good agreement. The differences detected in the biological activities of the conjugates may be explained in part by their tendency to penetrate the cell membrane.  相似文献   
124.
Pre‐slaughter handling involves fasting fish and catching them, which can affect fish welfare and flesh quality, but few studies have considered their combined effects. In this study, adult rainbow trout (320 ± 10 g average weight) were fasted for 7 days (135.6 degree days) and subjected to a long catch duration (20 min), compared with controls (no fasting or short catch duration). Condition factor, organ weight indexes and carcass yield decreased with fasting but not catch duration. Plasma concentrations of cortisol, glucose and lactate increased after a long catch, while plasma triglycerides decreased with fasting. Liver glycogen concentration was lower in fasted fish, and liver luminosity and chroma were higher after fasting with a long catch. Regarding flesh quality, rigor mortis resolved more slowly and final muscle pH at 48 hr post‐mortem was higher for fasted fish with a long catch time. Muscle glycogen concentration was higher in fasted fish, where chroma was also lower. Fasted fish had lower lipid oxidation, but there were no differences in fat content in muscle. Fasted fish with a long catch duration also had less monounsaturated and more saturated fatty acids. In conclusion, a long catch triggered a stress response that had negative effects on flesh quality, independently of fasting.  相似文献   
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