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排序方式: 共有501条查询结果,搜索用时 515 毫秒
1.
A Lindner A Wahdati H Sommer 《Berliner und Münchener tier?rztliche Wochenschrift》1992,105(7):239-242
GSH-Px activity in blood and plasma of 269 horses was determined and interrelated to age, sex, and type of use or breed. Furthermore values in blood were related to hematocrit and hemoglobin contents. Trotters and riding horses had higher GSH-Px activities in plasma as well as in blood (0.83 +/- 0.22 and 0.79 +/- 0.23 U/ml plasma or 27.2 +/- 4.3 and 24.0 +/- 7.0 U/ml blood) than Thoroughbreds in training and yearlings (0.61 +/- 0.,14 and 0.56 +/- 0.16 U/ml plasma or 20.6 2 +/- 6.9 and 24.6 +/- 4.3 U/ml blood). 3 to 6 years old Thoroughbreds had higher GSH-Px-activities than 1 to 2 years old ones. Colts and fillies did not have differing values. 相似文献
2.
钾肥施用量对脐橙产量和品质的影响 总被引:30,自引:0,他引:30
1996~1999年连续4年在湖北省秭归县进行了脐橙钾肥施用量田间试验。结果表明,尽管各处理脐橙产量年度变化很大,但施钾显著提高产量和经济效益,1997~1999年施钾平均增产26.3%~41.8%,施钾(K2O)125、250、375kg/hm2年均增加纯利 10110、15840、9970元/hm2,产投比分别为 19.38、15.40和7.04;在试验条件下施钾(K2O)250kg/hm2增产效果最好;施钾有提高脐橙外观品质和内在品质的趋势,例如施钾提高或保持单果重、增加果皮厚度、提高维生素C含量等;但施钾对品质的影响年度间差异较大,尚需进一步研究。 相似文献
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A. Lindner Dr med vet l; P. von Wittke Dr. med vet; M. Schmald J. Kusserow H. Sommer Dr habil Dr med vet 《Journal of Equine Veterinary Science》1992,12(1)
Lactate kinetics in whole blood of horses was investigated after exercise of differing velocities and duration. The following categories of exercise were used: A: <11 m/second and >180 seconds (n=35), B: >11 m/second and <180 seconds (n=17) and C: <11 m/second and <180 s (n=10). The mean peak lactate concentration determined in horses in category A was 4.49 ± 2.21 mmol/1, in B, 16.32 ± 4.81 mmoVl and in C, 4.58 ± 1.59 mmol/l. While the maximum lactate concentrations in categories A and C were always found immediately after the exercise, the peaks in category B were measured between the first and tenth minute after exercise. Mean lactate concentrations measured at 2-minute intervals after bouts of category-B exercise tended to stabilize 3 to 10 minutes after exercise; however, mean lactate concentrations measured during the intervals before and after the peak value differed significantly. The lactate concentration returned to pre-exercise levels within 20 minutes after exercise bouts of category C, but remained above pre-exercise levels up to 60 minutes after bouts of category-A and -B exercise. It was concluded that, for an evaluation of lactate data after intensive anaerobic exercise, sequential blood sampling at 2-minute intervals for a period of up to 12 minutes after exercise is necessary. Less frequent sampling may be a reason for the often described irreproducibility of lactate concentrations in horses. After aerobic or mild anaerobic exercise, one sample is sufficient, but it has to be taken as soon as possible after exercise. 相似文献
5.
Stina Fjelkner-Modig Håkan Bengtsson Stig Nystrõm Rolf Stegmark 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):102-113
In a six-year crop rotation trial organically and integrated grown vegetables were produced according to current good agricultural practices, taking quality and quantity aspects into consideration. The raw materials assessed focussed on materials used for industrial food production. Nutritional, sensory and agricultural aspects were evaluated. Carrot, cabbage, onion, pea and potato are possible to grow organically for industrial purposes. Depending on crop, the yield was lower (65-90%) for organically grown compared to integrated grown. Cultivation of organic spinach and dill turned out to be difficult due to problems with weed and discoloration. The chemical analyses included pesticide residues, nitrate, glycoalkaloid, dry matter, vitamin C and 25 different minerals and trace elements. Overall, the organically grown crops had higher dry matter content than the integrated grown. However, when examining the data for the different crops contradictory results were noted. No significant differences due to growing system were noticed for vitamin C and the other nutrients except for 4 of the trace elements. The growing system did not influence the sensory properties. 相似文献
6.
Petr Masner Christopher C. Steel Rolf Furter Hans Peter Isenring Gottfried Oesterhelt Hugo Ziegler Peter Zobrist 《Pest management science》1992,35(4):339-347
The activity of five experimental fungicides combining structural elements responsible for sterol C-14 demethylase inhibition and sterol nuclear double-bond transformations has been investigated by examining sterol accumulation in Ustilago maydis (DC.) Corda, inhibition of sterol-biosynthesis enzymes in Saccharomyces cerevisiae Meyer using a cell-free system and protective activity in cereals against Erysiphe graminis DC. and Puccinia coronata Corda. Combining the fenpropidin/fenpropimorph basic structure with a pyridine moiety offered no advantage in fungicidal activity. However, the combination of the pyrifenox structure with a morpholine moiety yielded a compound which was a good inhibitor of C-14 demethylase and Δ8 → Δ7 isomerase in vitro and gave good cereal protection. 相似文献
7.
Influence of low phosphorus intake during early lactation on apparent digestibility of phosphorus and bone metabolism in dairy cows 总被引:1,自引:0,他引:1
In this study, the effects of reducing the dietary phosphorus (P) supply during the first 4 months of lactation on P balance and bone metabolism were investigated in dairy cows during a full lactation, including the dry period. Twenty-two multiparous cows of the Swedish Red and White Breed were included in the experiment. Eleven cows received a dietary P concentration of 0.43% of DM during the whole lactation (NP), and 11 cows received a dietary P concentration of 0.32% of DM during the first 4 months of lactation, followed by 0.43% of DM during the rest of lactation (LP). Total collection of faeces was carried out during five different stages of lactation, for 5 consecutive days at each occasion. The dynamics of bone metabolism was investigated by monitoring one bone-formation marker, identifying osteocalcin (OC), and one bone-resorption marker identifying C-telopeptide fragments of collagen type I (CTx) in blood plasma. At the two first collection periods, 3–7 and 11–15 weeks after parturition, the apparent digestibility of P was higher in the LP cows (52%) than in the NP cows (42%). During the following collection periods, no difference in the apparent digestibility could be noted between the two groups of cows. Phosphorus retention did not differ between treatments at any collection period. The highest retention was observed during late lactation and during the dry period. The profiles of the bone metabolism markers indicated a net resorption of bone during early lactation, but there were no differences in marker concentrations between the groups during early lactation, indicating that the LP diet did not induce a further elevated net bone resorption. 相似文献
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Stocking control concepts in uneven-aged silviculture 总被引:2,自引:0,他引:2