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91.
S. Kumar Sunil Kumar S. P. Negi J. K. Kanwar 《In vitro cellular & developmental biology. Plant》2008,44(6):474-479
Callus cultures derived from leaf segments of chrysanthemum cultivar ‘Snow Ball’ which was susceptible to Septoria obesa were successfully used for in vitro selection for resistance to this pathogenic fungus. Resistant cell lines were selected by culturing callus on growth medium
containing various concentrations of S. obesa filtrate. Resistant calluses obtained after two cycles (30 d each cycle) of selection were used for plant regeneration. About
30% of the plants regenerated from the resistant calluses and 70–80% of the plants raised from cuttings had acquired considerable
resistance against the pathogen in the field. No phenotypic variation was observed in the selected regenerates. 相似文献
92.
93.
Vertical ionization energies (VIEs) of medazepam, nordazepam and their molecular subunits have been calculated using the electron
propagator method in the P3/CEP-31G* approximation. Vertical electron affinities (VEAs) have been obtained with a ∆SCF procedure
at the DFT-B3LYP/6-31+G* level of theory. Excellent correlations have been achieved between IEcalc and IEexp, allowing reliable assignment of the ionization processes. Our proposed assignment differs in many instances from that previously
reported in the literature. The electronic structure of the frontier Dyson orbitals shows that the IE and EA values of the
benzodiazepines can be modulated by substitution at the benzene rings. Hardness values, evaluated as (IE − EA)/2, follow the
trend of the experimental singlet transition energies. Medazepam is a less hard (i.e., less stable) compound than nordazepam. 相似文献
94.
Background
Plant lipoxygenases (LOXs) have been proposed to form biologically active compounds both during normal developmental stages such as germination or growth as well as during responses to environmental stress such as wounding or pathogen attack. In our previous study, we found that enzyme activity of endogenous 9-LOX in Nicotiana benthamiana was highly induced by agroinfiltration using a tobacco mosaic virus (TMV) based vector system. 相似文献95.
Background
Since the first well-known electrocardiogram (ECG) delineator based on Wavelet Transform (WT) presented by Li et al. in 1995, a significant research effort has been devoted to the exploitation of this promising method. Its ability to reliably delineate the major waveform components (mono- or bi-phasic P wave, QRS, and mono- or bi-phasic T wave) would make it a suitable candidate for efficient online processing of ambulatory ECG signals. Unfortunately, previous implementations of this method adopt non-linear operators such as root mean square (RMS) or floating point algebra, which are computationally demanding. 相似文献96.
97.
98.
John Herbert Parsons 《BMJ (Clinical research ed.)》1944,1(4342):430-431
99.
100.
Recent studies suggest that evergreen plants may maintain their photosynthetic capacity through the winter. Since mild winters
are predicted to be more frequent in the future, the metabolic activity of plants is also likely to increase. The aim of the
present study was to assess how various environmental factors, such as temperature, photoperiod and preceding frost, affect
the recovery of photosynthesis during a mild spell in winter. The recovery of photosynthesis was studied in a series of growth
chamber experiments where the overwintering of lingonberry (Vaccinium vitis-idaea) was interrupted by an intermittent warm spell of 1 week during different phases of winter. Rapid activation was observed
in all the experiments during the first 3–4 days. No obvious effects of the phase of winter or photoperiod on the recovery
of photosynthesis were observed, but a severe freezing treatment prior to the warm spell retarded the recovery significantly.
Once recovered, however, lingonberry was able to maintain high rates of photosynthesis even at near-freezing temperatures,
which prevail in their natural sub-nivean environment. The apparent quantum yield of photosynthesis remained high through
the winter for lingonberry. This may prove advantageous for evergreen dwarf shrubs which overwinter in dim environments under
snow. 相似文献