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1.
Kolb E 《Science (New York, N.Y.)》1983,222(4628):1116-1117
2.
The effects of sufficient milk intake as well as of 32 hours of fasting after birth, administration of actinomycin D (intraperitoneal application of 1 mg/kg five weight), and fasting in combination with actinomycin D on the development of body and liver weights, crude protein levels in homogenate and supernatant of liver, kidneys, and M. semitendinosus as well as on the activities of certain tissue enzymes were analysed with four groups of piglets (n = 4). Fasting, administration of actinomycin, and fasting in combination with actinomycin D resulted in rapid reduction in body and liver weights, while the crude protein levels in those tissues were not affected with significance. GOT and fructose-1,6-diphosphatase activities in supernatant from liver tended to decline under fasting conditions. The ATPase activity in the homogenate of the above tissues did not change in response to differentiated treatment. 相似文献
3.
Diplomlandwirt Erich Kuhn 《Journal of pest science》1926,2(9):126-127
Ohne Zusammenfassung 相似文献
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İsmail Hakkı Nur William Pérez Horst Erich König 《Anatomia, histologia, embryologia》2021,50(3):658-667
This study aims to reveal the morphological properties of facial nerve and the middle ear in Van cats. Study material was composed of 6 female Van cats. Dissections were performed under a Zoom Stereo Microscope. There was no plexus buccalis in Van cats. The chorda tympani was observed to pass through an opening in the tympanic cavity, emerge through a small opening just behind the retroarticular process, and join the lingual nerve. A rounded anatomical formation with a size of 2.75 ± 0.3 mm was found to be located within the mastoid process of the temporal bone between the facial nerve and the auricular branch of the vagus nerve. The stapes nerve was not present. The geniculate ganglion was very prominent and about 1.00 mm high. The deep petrosal nerve was observed to emerge from the plexus tympanicus. The bulla tympanica was 18.96 ± 0.10 mm long, 13.03 ± 0.20 mm wide and 13.16 ± 0.20 mm high. After leaving the mandibular nerve, the n.tensoris tympani coursed caudally around the a.maxillaris, formed an ansa, entered the tympanic cavity through the canalis musculotubarius and reached an end in the m. tensor tympani. Due to the scarcity of studies on the middle ears of Van cats, it is thought that this study will fill a gap in the field of veterinary anatomy. 相似文献
6.
Erich Seemüller Eckard Moll Bernd Schneider 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(2):217-223
Progenies of 39 open-pollinated genotypes belonging to 26 Pyrus taxa were examined for pear decline resistance and pomological traits when used as rootstocks. Following graft inoculation
and observation over 18 years, considerable differences in pear decline resistance between and within the progenies were observed.
Not affected or little affected and moderately to severely affected trees were observed in all progenies. However, great quantitative
differences among them were observed. In the progenies of about one third of the pollinated trees most of the individuals
showed a high level of resistance to grafted trees. Significantly different from this group was another third of the progenies
that mostly showed high susceptibility in grafted trees. Between these two groups there were progenies that statistically
neither differed from the resistant nor from the susceptible group. These progenies were defined as moderately resistant.
Significant differences in resistance were also observed between progenies of genotypes of the same species that originated
from different locations. These data indicate segregation of the resistance trait and show that seedling progenies are unsuitable
as rootstocks in commercial pear growing. Instead, careful selection of suitable genotypes for propagation is required. Great
differences between and within the progenies examined were also observed in vigour and yield efficiency. 相似文献
7.
ABSTRACT Three cultivars of soft red winter wheat were evaluated to determine the relationship between the incidence and time of infection by Barley yellow dwarf virus (BYDV) and yield. Wheat was planted in 1995, 1996, and 1997 in a split-plot design with six replicates at sites in Indiana and Illinois. Yield plots were infested with different amounts of viruliferous aphids, and the incidence of BYDV in each plot was measured. In a 2-year study in Illinois with cv. Clark and the PAV-IL isolate of BYDV, yields were assessed following aphid infestation in fall, early spring, and late spring. Early spring infections resulted in larger yield reductions than late spring infections in both years and larger than fall infections in one year. Regression analyses to relate incidence of infection and yield with data from fall and early spring infections provided R(2) values of 0.89 and 0.51 for the 1996 to 1997 and 1997 to 1998 seasons, respectively. An additional study at the same site in the 1996 to 1997 season compared the yield responses of cvs. Clark, Y88-3e, and PT8935b. Increases in the incidence of BYDV correlated with decreases in yield, with R(2) values of 0.80, 0.78, and 0.90 for the three cultivars, respectively. Estimated yield losses in both studies and all cultivars ranged from 27 to 45 kg/ha or 0.34 to 0.55% for each percent increase in virus infection. In a third study over a 2-year period in Indiana with the same three wheat genot ypes and a second BYDV isolate (PAV-P), BYDV treatments resulted in significant reductions in yield, but yield loss and the incidence of BYDV were not linearly correlated. Given the differences in yield reductions caused by the two BYDV isolates, PAV-P may be an attenuated strain of BYDV and may cross-protect plants from naturally occurring strains of the virus. 相似文献
8.
Although we know that alterations in crop density, crop spatial pattern and inclusion of more selective weed control can improve weed suppression for organic growers, it is unknown whether these result in changes to the weed seedbank that increase cropping system profitability over time. Data collected from field trials conducted in 2009 and 2010 in Maine, USA, comparing regional grower practices (Standard) with management that aimed to (i) facilitate better physical weed control through the use of wide row spacing and inter‐row cultivation (Wide) or (ii) enhance crop–weed competition through increased seeding rate and narrow inter‐row spacing (Narrow HD), were used to construct a matrix population model with an economic sub‐model. Using field measurements of grain yield and weed survival and fecundity, we investigated the lasting implications of employing alternative organic spring wheat (Triticum aestivum) production practices on Sinapis arvensis population dynamics. In most scenarios, the model indicated that regional production practices were not sufficient to prevent an increase in the weed seedbank, even with excellent weed control. The two alternative methods, on the other hand, were able to limit weed population growth when initial densities were low or cultivation efficacy was >80%. Due to higher seed costs in the Narrow HD system, net returns were still lower after 10 years of simulation in this system compared with wide rows with cultivation, despite a lower weed seedbank. 相似文献
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