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41.
The forty-two days long experiment was conducted on a total of 1000 Arbor Acres broilers, divided into two groups. Both groups
of broilers were fed with a commercial feed mixture which consisted of standard feedstuffs and contained enough nutrients
regarding the requirements. During the first three weeks of the trial, corn naturally contaminated with AFB1 0.0445 ppm per kg dry matter was used in the amount of 20% in the experimental group, while AFB1 free corn was given to birds in the control group. After the period of toxin administration until the end of the trial, broilers
from both groups were normally fed another 5 weeks with uncontaminated feed.
In the first phase of the trial, broilers in the control groups had an average daily gain (ADG) of 31 g, average daily feed
intake (ADFI) of 45 g and a feed: gain ratio (FCR) of 1.42. In the same time, experimental broilers achieved an ADG of 25
g, ADFI of 35 g and a FCR of 1.39. During the whole period of the trial, control and experimental broilers achieved 49.12
g, 95.24 g and 1.94 and 39.71 g, 86.90 g and 2.19, respectively. 相似文献
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43.
Spencer G. Lucas Bolat U. Bayshashov Lyubov A. Tyutkova Ayzhan K. Zhamangara Bolat Z. Aubekerov 《Pal?ontologische Zeitschrift》1997,71(3-4):305-314
At Aktau Mountain in the Ili depression of eastern Kazakstan, fossil mammals that encompass the Paleogene-Neogene boundary occur at three stratigraphic levels. The lowest level is in the lower Kyzylbulak Formation and produces Brontotheriidae and the hyracodontidArdynia and is tentatively assigned a late Eocene (Ergilian) age. The lower part of the overlying Aktau Formation produces fossils of the giant rhinocerosParaceratherium and is tentatively assigned a late Oligocene (Tabenbulukian) age. The upper part of the Aktau Formation yields a fossil mammal assemblage that includesGomphotherium,Stephanocemas, Brachypotherium andLagomeryx. It is clearly of Miocene age, probably late early Miocene (late Burdigalian), a correlative of European Reference Level MN 5 and the late Shanwangian of China. The Paleogene-Neogene boundary at Aktau Mountain thus is in the Aktau Formation. 相似文献
44.
A Sólyom S Tóth I Holczinger J Vajda Z Tóth R Kálmánchey 《Applied neurophysiology》1985,48(1-6):222-225
Four thalamic and cortical recordings were carried out in 5 patients. The thalamic-evoked potentials were typical and revealed a triphasic complex, but their latencies showed a relatively high standard deviation. They could be divided into two groups according to their latencies, both of which had low SD. These data suggested that there could be two types of latency of thalamic SEP, because the 4 patients' body sizes were very similar. More detailed surface, cortical and depth recordings are needed to resolve these questions. 相似文献
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48.
Tsyganov V. E.; Pavlova Z. B.; Kravchenko L. V.; Rozov S. M.; Borisov A. Y.; Lutova L. A.; Tikhonovich I. A. 《Annals of botany》2000,86(5):975-981
Using ethyl methane sulfonate (EMS) treatment of the seeds ofline SGE, a new mutant of pea (Pisum sativum L.) with alterationsin root development was obtained. The mutant phenotype dependson the density of the growth substrate: on sand (a high densitysubstrate) the mutant forms a small compact curly root systemwhereas on vermiculite (a low density substrate) differencesbetween the root systems of the mutant and wild type plantsare less pronounced. Genetic analysis revealed that the mutantcarries a mutation in a new pea gene designedcrt (curly roots).Gene crt has been localized in pea linkage group V. The mutantline named SGEcrt showed increased sensitivity to exogenousauxin and an increased concentration of endogenous indole-3-aceticacid (IAA) in comparison with the wild type line SGE. Copyright2000 Annals of Botany Company Pisum sativum L., root development, garden pea mutant, curly roots, auxin, environmental stimulus response 相似文献
49.
Wojciech Leszczyński Krzysztof Ślosarek Marta Szlag 《Reports of Practical Oncology and Radiotherapy》2012,17(6):347-351
AimThe aim was to provide a dosimetric comparison between IMRT and RapidArc treatment plans with RPI index with simultaneous comparison of the treatment delivery time.BackgroundIMRT and RapidArc provide highly conformal dose distribution with good sparing of normal tissues. However, a complex spatial dosimetry of IMRT and RapidArc plans hampers the evaluation and comparison between plans calculated for the two modalities. RPI was used in this paper for treatment plan comparisons. The duration of the therapeutic session in RapidArc is reported to be shorter in comparison to therapeutic time of the other dynamic techniques. For this reasons, total treatment delivery time in both techniques was compared and discussed.Materials and methods15 patients with prostate carcinoma were randomly selected for the analysis. Two competitive treatment plans using respectively the IMRT and RapidArc techniques were computed for each patient in Eclipse planning system v. 8.6.15. RPIwin® application was used for RPI calculations for each treatment plan.Additionally, total treatment time was compared between IMRT and RapidArc plans. Total treatment time was a sum of monitor units (MU) for each treated field.ResultsThe mean values of the RPI indices were insignificantly higher for IMRT plans in comparison to rotational therapy. Comparison of the mean numbers of monitor units confirmed that the use of rotational technique instead of conventional static field IMRT can significantly reduce the treatment time.ConclusionAnalysis presented in this paper, demonstrated that RapidArc can compete with the IMRT technique in the field of treatment plan dosimetry reducing the time required for dose delivery. 相似文献
50.
Effect of precursors on biosynthesis of monensins A and B 总被引:1,自引:0,他引:1
Precursors of monensins (acetate, propionate, butyrate, isobutyrate) affect the total production and the relative proportion of monensins A and B. Addition of propionate into the fermentation medium causes a prevalence of monensin B whereas butyrate and isobutyrate stimulate the production of monensin A and suppress the production of monensin B. 相似文献