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1.
Bruno Von Berzins 《Hydrobiologia》1954,6(3-4):309-320
Ohne Zusammenfassung 相似文献
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Viesturs UE Strikauska SV Leite MP Berzins AJ Tengerdy RP 《Biotechnology and bioengineering》1987,30(2):282-288
A novel two-stage bioreactor has been designed for a combined submerged (SF) and solid substrate fermentation (SSF) of wheat straw. The straw was pretreated with steam, and cellulases from the culture fluid of Trichoderma reesei were adsorbed on it for increased bioconvertibility. SSF was conducted in the top part of the bioreactor by inoculating the straw with a 36-h mycelial culture of T. reesei, or Coriolus versicolor. In the bottom part of the fermenter, Endomycopsis fibuliger was grown in SF. The SF liquor was recirculated through the SSF stage at 24 h intervals to remove glucose and other metabolites that may inhibit growth, and to maintain optimum moisture level and temperature. The removed glucose and other metabolites provided nutrients for the yeast in the SF stage. The combined fermentation resulted in overall higher biomass yield, increased bioconversion, increased cellulase production, and increased digestibility compared with single SSF or SF. 相似文献
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Sampling properties of DNA sequence data in phylogenetic analysis 总被引:26,自引:6,他引:20
We inferred phylogenetic trees from individual genes and random samples of
nucleotides from the mitochondrial genomes of 10 vertebrates and compared
the results to those obtained by analyzing the whole genomes. Individual
genes are poor samples in that they infrequently lead to the whole-genome
tree. A large number of nucleotide sites is needed to exactly determine the
whole-genome tree. A relatively small number of sites, however, often
results in a tree close to the whole-genome tree. We found that blocks of
contiguous sites were less likely to lead to the whole-genome tree than
samples composed of sites drawn individually from throughout the genome.
Samples of contiguous sites are not representative of the entire genome, a
condition that violates a basic assumption of the bootstrap method as it is
applied in phylogenetic studies.
相似文献
6.
BACKGROUND: Morbidity management is a core component of the global programme for the elimination of lymphatic filariasis. In a double-blind clinical trial, the tolerability and efficacy of Daflon (500 mg) + DEC (25 mg) or DEC (25 mg) alone, twice daily for 90 days, was studied in 26 patients with bancroftian filarial lymphoedema. RESULTS: None of the patients in either drug group reported any adverse reaction throughout the treatment period (90 days). Haematological and biochemical parameters were within normal limits and there was no significant difference between the pre-treatment (day 0) and post-treatment (day 90) values. The group receiving Daflon showed significant reduction in oedema volume from day 90 (140.6 PlusMinus; 18.8 ml) to day 360 (71.8 PlusMinus; 20.7 ml) compared to the pre-treatment (day 0, 198.4 PlusMinus; 16.5 ml) value. This accounted for a 63.8% reduction in oedema volume by day 360 (considering the pre-treatment (day 0) as 100%). In the DEC group, the changes in oedema volume (between day 1 and day 360) were not significant when compared to the pre-treatment (day 0) value. The percentage reduction at day 360 was only 9%, which was not significant (P > 0.05). CONCLUSION: This study has shown that Daflon (500 mg, twice a day for 90 days) is both safe and efficacious in reducing oedema volume in bancroftian filarial lymphoedema. Further clinical trials are essential for strengthening the evidence base on the role of this drug in the morbidity management of lymphatic filariasis. 相似文献
7.
IL-21 is produced by NKT cells and modulates NKT cell activation and cytokine production 总被引:12,自引:0,他引:12
Coquet JM Kyparissoudis K Pellicci DG Besra G Berzins SP Smyth MJ Godfrey DI 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(5):2827-2834
The common gamma-chain cytokine, IL-21, is produced by CD4(+) T cells and mediates potent effects on a variety of immune cells including NK, T, and B cells. NKT cells express the receptor for IL-21; however, the effect of this cytokine on NKT cell function has not been studied. We show that IL-21 on its own enhances survival of NKT cells in vitro, and IL-21 increases the proliferation of NKT cells in combination with IL-2 or IL-15, and particularly with the CD1d-restricted glycosphingolipid Ag alpha-galactosylceramide. Similar to its effects on NK cells, IL-21 enhances NKT cell granular morphology, including granzyme B expression, and some inhibitory NK receptors, including Ly49C/I and CD94. IL-21 also enhanced NKT cell cytokine production in response to anti-CD3/CD28 in vitro. Furthermore, NKT cells may be subject to autocrine IL-21-mediated stimulation because they are potent producers of this cytokine following in vitro stimulation via CD3 and CD28, particularly in conjunction with IL-12 or following in vivo stimulation with alpha-galactosylceramide. Indeed, NKT cells produced much higher levels of IL-21 than conventional CD4 T cells in this assay. This study demonstrates that NKT cells are potentially a major source of IL-21, and that IL-21 may be an important factor in NKT cell-mediated immune regulation, both in its effects on NK, T, and B cells, as well as direct effects on NKT cells themselves. The influence of IL-21 in NKT cell-dependent models of tumor rejection, microbial clearance, autoimmunity, and allergy should be the subject of future investigations. 相似文献
8.
McNab FW Pellicci DG Field K Besra G Smyth MJ Godfrey DI Berzins SP 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(10):6630-6637
One interesting aspect of NKT cell development is that although they are thymus dependent, the pivotal transition from NK1.1(-) to NK1.1(+) can often take place after immature NK1.1(-) NKT cells are exported to the periphery. NK1.1(-) NKT cells in general are regarded as immature precursors of NK1.1(+) NKT cells, meaning that peripheral NK1.1(-) NKT cells are regarded as a transient, semimature population of recent thymic emigrant NKT cells. In this study, we report the unexpected finding that most NK1.1(-) NKT cells in the periphery of naive mice are actually part of a stable, mature and functionally distinct NKT cell population. Using adult thymectomy, we show that the size of the peripheral NK1.1(-) NKT cell pool is maintained independently of thymic export and is not the result of NK1.1 down-regulation by mature cells. We also demonstrate that most peripheral NK1.1(-) NKT cells are functionally distinct from their immature thymic counterparts, and from NK1.1(+) NKT cells in the periphery. We conclude that the vast majority of peripheral NK1.1(-) NKT cells are part of a previously unrecognized, mature NKT cell subset. 相似文献
9.
Gross,histological and ultrastructural morphology of the aglomerular kidney in the lined seahorse Hippocampus erectus 下载免费PDF全文
S. B. Fogelson R. P. E. Yanong A. Kane C. N. Teal I. K. Berzins S. A. Smith C. Brown A. Camus 《Journal of fish biology》2015,87(3):805-813
Histologic evaluation of the renal system in the lined seahorse Hippocampus erectus reveals a cranial kidney with low to moderate cellularity, composed of a central dorsal aorta, endothelial lined capillary sinusoids, haematopoietic tissue, fine fibrovascular stroma, ganglia and no nephrons. In comparison, the caudal kidney is moderately to highly cellular with numerous highly convoluted epithelial lined tubules separated by interlacing haematopoietic tissue, no glomeruli, fine fibrovascular stroma, numerous capillary sinusoids, corpuscles of Stannius and clusters of endocrine cells adjacent to large calibre vessels. Ultrastructural evaluation of the renal tubules reveals minimal variability of the tubule epithelium throughout the length of the nephron and the majority of tubules are characterized by epithelial cells with few apical microvilli, elaborate basal membrane infolding, rare electron dense granules and abundant supporting collagenous matrix. 相似文献