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1.
News     
K. Bremer 《Potato Research》1960,3(2):199-198
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G. Bremer 《Euphytica》1962,11(1):65-80
In Part V the phenomenon endo-duplication of chromosomes within embryo-sac mother cells—cause of the increase in chromosome number within species hybrids of Saccharum—was discussed.Special cases of change in chromosome number by hybridization of sugar cane, which formerly were inconceivable, appeared to be based on endo-duplication.In Saccharum species hybrids with an increased chromosome number equalling twice the haploid number of the female parent plus once the haploid number of the male parent, are of such a frequent occurrence that they may be called normal.Also within other genera interspecific and intergeneric hybrids are known of which the somatic chromosome numbers show the same kind of increase. They are, however, less numerous than in Saccharum. Of agricultural plants we know them for instance in Solanum (potato), in intergeneric hybrids between Lolium and Festuca and in hybrids between Triticum monococcum and T. turgidum. In horticultural plants they occur in Cyclamen. About the mode of origin of such hybrids opinions are not uniform. In this article the possibility is considered whether the chromosome increase in such hybrids may be interpreted in the same way as in Saccharum.  相似文献   
3.
The influence of transplanting on height, root neck diameter, and grading was investigated for Carpinus betulus, Quercus robur, and Euonymus europaeus on three sites with different climate and soil properties. Additionally, plant growth was characterized by the shoot-to-root ratio, height-to-root neck diameter, and proportions of coarse and fine roots. The significance of the growth parameters as criteria for survival is discussed. Transplanting influenced shoot growth more than root growth. The growth of the plants was highly site-dependent. Transplanting increased growth most on the site with the best conditions for water and N supply. Transplanting had no effect on grading for the site with the worst water supply.  相似文献   
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Corn milling byproducts are expected to increase dramatically in supply as the ethanol industry expands. Distillers grains, corn gluten feed, or a combination of both byproducts offer many feeding options when included in feedlot rations. These byproduct feeds may effectively improve cattle performance and operation profitability. When these byproducts are fed in feedlot diets, adjustments to grain processing method and roughage level may improve cattle performance. Innovative storage methods for wet byproducts and the use of dried byproducts offer small operations flexibility when using byproducts. As new byproducts are developed by ethanol plants, they should be evaluated with performance data to determine their product-specific feeding values.  相似文献   
6.
The pharmacokinetics of aditoprim (2,4-diam-ino-5-[4-[dimethylamino]-3,5-dimethoxybenzyl] pyrimidine), a dihydrofolate reductase inhibitor, were studied in three eight to 17-month-old beagle dogs. The drug was alternately injected intravenously and administered orally as a tablet in two separate experiments. The doses ranged from 4–27 to 7–25 mg/kg bodyweight. The mean plasma clearance (CI) was 15-3 ml/min/kg and the mean volume of distribution (Vss) 13-1 litres/kg. The mean plasma elimination half-life times after intravenous injection and oral administration were 11-6 and 9-6 hours, respectively. Aditoprim was readily (tmax= one to four hours) and completely absorbed from the intestinal tract (f = 89 per cent).  相似文献   
7.
AIM: To determine if the superficial digital flexor tendon (SDFT) of young Thoroughbred horses changed in size and echogenicity in association with early race training.

METHODS: Cross-sectional area (CSA) and echogenicity were determined ultrasonographically at five levels of the SDFT of the forelimbs of 2-year-old fillies (n=14), corresponding to 4, 8, 12, 16 and 20 cm distal to the accessory carpal bone (DACB). Measurements were made before and after a 13-week period in which a trained group of seven horses was compared with another group of seven untrained horses.

RESULTS: Level below the accessory carpal bone had a significant effect on CSA and Level 8 was smaller than all other levels except Level 12, while Level 12 was smaller than Levels 4 and 20 but not different from Levels 8 and 16. There was a significant interaction between level and time due to effects observed at Level 8. The CSA at Level 8 measured pre-training was different from that of Levels 4 and 20 in both pre- and post-training groups (p<0.05), but when measured post-training was not different from any other measurement. There was also a significant interaction between treatment group and time. There was no difference between CSA for the untrained and trained groups at the pre-training observation (p=0.9), but post-training the CSA (pooled over all levels) in trained horses was significantly larger than that of the untrained horses both post-training (p=0.019) and pre-training (p=0.034), and was not different from the pretraining CSA recorded in the trained group (p=0.29). Treatment group had no effect on echogenicity (p=0.43), while echogenicity was less at the end of the trial in both trained and untrained horses (p<0.001).

CONCLUSIONS: Early training for racing was associated with an increase in mean CSA of the SDFT. Other factors such as age and maturity may play a role in limiting this increase.  相似文献   
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Ohne Zusammenfassung Zweigstelle Kiel der Biologischen Reichsanstalt für Land- und Forstwirtschaft  相似文献   
10.
Zusammenfassung Die beste und billigste Abwehr gegen Bohnenfliegenschaden besteht zur Zeit in der Saatgutbeizung mit einem Insektizid und Fungizid enthaltenden Beizmittel. Bei Verwendung eines Anklebemittels zum Saatgut kann und muß die Beizmittelmenge auf die Hälfte herabgesetzt werden. Die Saatgutbeizung lohnt sich bei Aussaat zu verschiedenen Zeiten der Vegetationsperiode.  相似文献   
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