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101.
Ana Cecília Afonso Roque Ana Sofia Pina Ana Margarida Azevedo Raquel Aires‐Barros Alois Jungbauer Gianluca Di Profio Jerry Y. Y. Heng Jonathan Haigh Marcel Ottens 《Biotechnology journal》2020,15(8)
While packed bed chromatography, known as conventional chromatography, has been serving the biopharmaceutical industry for decades as the bioseparation method of choice, alternative approaches are likely to take an increasing leading role in the next few years. The high number of new biological drugs under development, and the need to make biopharmaceuticals widely accessible, has been driving the academia and industry in the quest of anything but conventional chromatography approaches. In this perspective paper, these alternative approaches are discussed in view of current and future challenges in the downstream processing field. 相似文献
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Alois Teyber 《Plant Systematics and Evolution》1913,63(1):21-29
Ohne Zusammenfassung 相似文献
104.
Alois Tavčar 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1931,3(11):333-338
Ohne Zusammenfassung 相似文献
105.
Ohne Zusammenfassung 相似文献
106.
The estimation of motion direction from time varying retinal images is a fundamental task of visual systems. Neurons that
selectively respond to directional visual motion are found in almost all species. In many of them already in the retina direction
selective neurons signal their preferred direction of movement. Scientific evidences suggest that direction selectivity is
carried from the retina to higher brain areas. Here we adopt a simple integrate-and-fire neuron model, inspired by recent
work of Casti et al. (2008), to investigate how directional selectivity changes in cells postsynaptic to directional selective retinal ganglion cells
(DSRGC). Our model analysis shows that directional selectivity in the postsynaptic cells increases over a wide parameter range.
The degree of directional selectivity positively correlates with the probability of burst-like firing of presynaptic DSRGCs.
Postsynaptic potentials summation and spike threshold act together as a temporal filter upon the input spike train. Prior
to the intricacy of neural circuitry between retina and higher brain areas, we suggest that sharpening is a straightforward
result of the intrinsic spiking pattern of the DSRGCs combined with the summation of excitatory postsynaptic potentials and
the spike threshold in postsynaptic neurons. 相似文献
107.
Eighteen Beagle dogs were used to evaluate the effects of bovine lactoferrin (bLF) on immune function and faecal microbial populations. The study comprised three feeding periods, each lasting four weeks. After an initial control Period 1, six dogs per group were supplemented with 0, 120 and 1800 mg bLF/kg dry diet, respectively (Period 2). In Period 3 dogs received again control diets. Peripheral blood mononuclear cell subsets, lymphocyte proliferative response to concanavalin A, phytohaemagglutinin and pokeweed mitogen and plasma IgA and IgG concentrations were analysed. The faecal concentrations of aerobic and anaerobic bacteria, Escherichia coli, Clostridium perfringens, Lactobacillus spp. and Bifidobacterium spp. were determined by cultural methods. Supplementation of bLF increased the number of monocytes, T cells and cytotoxic T cells in the blood and the proliferative response of peripheral blood mononuclear cells. The leukocyte counts were not affected, except monocytes that increased after the supplementation with bLF. Plasma immunoglobulin concentrations were unchanged by treatment. Dogs supplemented with bLF tended to have lower faecal concentrations of E. coli and Clostridium perfringens. In conclusion, bLF seems to alter indices of the cellular immune response and faecal microbial populations of healthy adult dogs. 相似文献
108.
Ralf Oelmüller Alois Schneiderbauer Reinhold G. Herrmann Klaus Kloppstech 《Molecular & general genetics : MGG》1995,246(4):478-484
Steady-state mRNA levels for thylakoid proteins were analysed in spinach cotyledons under diurnally changing light conditions. Most fluctuate considerably throughout the day, while the levels of others show only low amplitude or no oscillation. Levels of mRNAs coding for proteins that belong to the same multiprotein complex generally oscillate in parallel and exhibit maxima that are specific for that complex: mRNAs for photosystem I proteins appear prior to those for photosystem II polypeptides and these again prior to mRNAs for the three polypeptides constituting the oxygen-evolving complex. For the mRNAs that change with high amplitudes (e.g. those for LHCP or the 20 kDa apoprotein of the CP24 complex) oscillations have also been found under constant conditions, indicating that a circadian oscillator is involved. Transgenic tobacco seedlings harbouring chimeric GUS gene fusions with 5-flanking sequences from the spinach genes Lhcb, PsaF and AtpD (encoding a light-harvesting chlorophyll a/b apoprotein of photosystem II, subunit 3 of photosystem I and subunit of the plastid ATP synthase, respectively) confirm that the differences in the amplitudes as well as the timepoints of maximum mRNA accumulation are perceived via cis-regulatory elements upstream of the respective ATG codons. 相似文献
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