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781.
Calander AM Jonsson IM Kanth A Arvidsson S Shaw L Foster SJ Tarkowski A 《Microbes and infection / Institut Pasteur》2004,6(2):202-206
The exoproteases of Staphylococcus aureus have been proposed as virulence factors during S. aureus infections. To investigate this, we used the wild-type S. aureus strain 8325-4 and its mutants devoid of aureolysin, serine protease, and cysteine protease, respectively, in a well-established model of septic arthritis in mice. The inactivation of the exoprotease genes did not affect the frequency or the severity of joint disease. We conclude that in the model of haematogenously spread staphylococcal arthritis, the bacterial proteases studied do not act as virulence factors. 相似文献
782.
Optimal allocation of reproductive effort: manipulation of offspring number and size in the bank vole 总被引:2,自引:0,他引:2
Oksanen TA Jonsson P Koskela E Mappes T 《Proceedings. Biological sciences / The Royal Society》2001,268(1467):661-666
The number of offspring attaining reproductive age is an important measure of an individual's fitness. However, reproductive success is generally constrained by a trade-off between offspring number and quality. We conducted a factorial experiment in order to study the effects of an artificial enlargement of offspring number and size on the reproductive success of female bank voles (Clethrionomys glareolus). We also studied the effects of the manipulations on growth, survival and reproductive success of the offspring. Potentially confounding effects of varying maternal quality were avoided by cross-fostering. Our results showed that the number of offspring alive in the next breeding season was higher in offspring number manipulation groups, despite their smaller body size at weaning. Offspring size manipulation had no effect on offspring growth or survival. Further, the first litter size of female offspring did not differ between treatments. In conclusion, females may be able to increase the number of offspring reaching reproductive age by producing larger litters, whereas increasing offspring size benefits neither the mother nor the offspring. 相似文献
783.
T. Håstein A. Hellstrøm G. Jonsson N. J. Olesen E. R.- Pärnänen 《Acta veterinaria Scandinavica》2001,42(Z1):S43
Due to the increasing importance of disease problems in the fish farming industry and the impact disease may have on both feral and farmed fish in the Nordic countries, monitoring and surveillance on diseases have for many years been considered to be of socioeconomic importance. All the Nordic countries have a national legislation as basis for their surveillance and disease control in aquatic animals and regulations listing notifiable diseases of concern to the countries. The list of diseases vary between the countries. In addition, Denmark, Finland and Sweden are ruled by [3] as regards placing on the market of aquaculture animals and products. The surveillance for viral diseases in all the Nordic countries has mainly been based on the testing procedures given in the EU Commission [2]. 相似文献
784.
Analysis of behavioural rejection of micro-textured surfaces and implications for recruitment by the barnacle Balanus improvisus 总被引:2,自引:0,他引:2
Berntsson KM Jonsson PR Lejhall M Gatenholm P 《Journal of experimental marine biology and ecology》2000,251(1):59-83
Experiments performed in the field and in the laboratory show that the barnacle, Balanus improvisus, preferentially settles on smooth surfaces. Settlement and recruitment of B. improvisus was evaluated on micro-textured surfaces with scales of surface texture ranging from 1 to 100 μm in profile heights. Surface texture with profile heights within a topographic range of 30-45 μm reduced settlement and recruitment by 92% as compared to smooth surfaces. The reduction in recruitment on micro-textured surfaces is best explained by behavioural responses to surface topography. Behavioural experiments show that cyprids have a higher propensity for smooth surfaces than for micro-textured surfaces. Cyprids spend more time exploring smooth surfaces and more time swimming when exposed to micro-textured surfaces. Micro-textured surfaces are more often rejected by cyprids after exploration than smooth surfaces. It is suggested that some scales of surface texture could be exploited to improve future anti-fouling techniques in geographical areas where Balanus improvisus is a severe fouling problem. 相似文献
785.
786.
When rehabilitating and reintroducing trout Salmo trutta in rivers, it is a goal that as many as possible survive, home and form self-sustaining populations. Hatchery-reared, anadromous S. trutta have significant lower ability to return to the area where they were raised if (a) transported in a closed tank to sea and released 5 km from the River Imsa, relative to those that were (b) transported when swimming in a partly submerged tank with sea water run-through, while being slowly towed by a boat the same distance or (c) released at the outlet of the River Imsa. Thus, if deprived from environmental cues during part of the way, they lose their ability to home. 相似文献
787.
A. W. Schram E. J. M. Al N. Douma L. M. V. Jonsson P. de Vlaming A. Kooi G. J. H. Bennink 《Planta》1982,155(2):162-165
Limbs of flower buds from Petunia hybrida were investigated for -glucosidase activity with dihydroflavonol-glucosides and 4-methyl-umbelliferyl--D-glucoside as substrates. Dihydroflavonol-glucoside -glucosidase is localized in the cell wall. This activity has an acid pH optimum and is also active toward 4-methyl-umbelliferyl--glucoside. Besides this activity a neutral -glucosidase is present. This activity is soluble and is not active toward dihydroflavonol-glucosides. Using starch gel electrophoresis it was shown that no difference in -glucosidase activity is present between mutants able to convert dihydroflavonols into anthocyanins and mutants accumulating dihydroflavonol-glucosides. It is concluded that -glucosidase activity is not involved in anthocyanin synthesis.Abbreviations 4MU--glc
4-methylumbelliferyl--D-glucopyranoside
- dHQ-7-g
dihydroquercetin-7-glucoside
- dHQ-4-g
dihydroquercetin-4-glucoside
- dHM-4-g
dihydromyricetin-4-glucoside
Deceased 相似文献
788.
Satish Babu Moparthi Daniel Sjölander Laila Villebeck Bengt-Harald Jonsson Per Hammarström Uno Carlsson 《Journal of chemical biology》2014,7(1):1-15
The commonly accepted dogma of the bacterial GroE chaperonin system entails protein folding mediated by cycles of several ATP-dependent sequential steps where GroEL interacts with the folding client protein. In contrast, we herein report GroES-mediated dynamic remodeling (expansion and compression) of two different protein substrates during folding: the endogenous substrate MreB and carbonic anhydrase (HCAII), a well-characterized protein folding model. GroES was also found to influence GroEL binding induced unfolding and compression of the client protein underlining the synergistic activity of both chaperonins, even in the absence of ATP. This previously unidentified activity by GroES should have important implications for understanding the chaperonin mechanism and cellular stress response. Our findings necessitate a revision of the GroEL/ES mechanism. 相似文献
789.
St John JA Braun EL Isberg SR Miles LG Chong AY Gongora J Dalzell P Moran C Bed'hom B Abzhanov A Burgess SC Cooksey AM Castoe TA Crawford NG Densmore LD Drew JC Edwards SV Faircloth BC Fujita MK Greenwold MJ Hoffmann FG Howard JM Iguchi T Janes DE Khan SY Kohno S de Koning AJ Lance SL McCarthy FM McCormack JE Merchant ME Peterson DG Pollock DD Pourmand N Raney BJ Roessler KA Sanford JR Sawyer RH Schmidt CJ Triplett EW Tuberville TD Venegas-Anaya M Howard JT Jarvis ED Guillette LJ Glenn TC 《Genome biology》2012,13(1):415-12
The International Crocodilian Genomes Working Group (ICGWG) will sequence and assemble the American alligator (Alligator mississippiensis), saltwater crocodile (Crocodylus porosus) and Indian gharial (Gavialis gangeticus) genomes. The status of these projects and our planned analyses are described. 相似文献
790.
Stattin Eva-Lena Boström Ida Maria Winbo Annika Cederquist Kristina Jonasson Jenni Jonsson Björn-Anders Diamant Ulla-Britt Jensen Steen M Rydberg Annika Norberg Anna 《BMC cardiovascular disorders》2012,12(1):1-12