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91.
92.
Neal Gutterson 《Acta Botanica Sinica》2011,(3)
Selection of energy crops is the first priority for large-scale biofuel production in China. As a major topic, it was extensively discussed in the Second International Symposium on Bioen- 相似文献
93.
Shaddick K Burridge CP Jerry DR Schwartz TS Truong K Gilligan DM Beheregaray LB 《Journal of fish biology》2011,79(5):1214-1235
The presence and distribution of hybrid individuals and the existence of a hybrid zone between the catadromous Australian bass Macquaria novemaculeata and estuary perch Macquaria colonorum were investigated throughout the range of both species in Australia. Bayesian analyses and genotypic simulations identified 140 putative hybrids (11·5% of the total sample) with varying levels of introgression. Most hybrids were observed in an area extending from the Snowy River to the Albert River suggesting a hybrid zone in the eastern Bass Strait region. Sixteen hybrids, however, were found outside this zone, possibly reflecting the movement of hybrid offspring between estuaries or their inadvertent release during fish stocking programmes. Biparental backcrossing was found to occur suggesting that hybrids were fertile. These results have implications for the management of the extensive stocking programme in M. novemaculeata and for understanding the potential role of habitat degradation and reduced water flow in facilitating hybridization in species with migratory life histories. 相似文献
94.
van den Bosch F Jeger MJ Gilligan CA 《Proceedings. Biological sciences / The Royal Society》2007,274(1606):11-18
Viral diseases are a key constraint in the production of staple food crops in lesser developed countries. New and improved disease control methods are developed and implemented without consideration of the selective pressure they impose on the virus. In this paper, we analyse the evolution of within-plant virus titre as a response to the implementation of a range of disease control methods. We show that the development of new and improved disease control methods for viral diseases of vegetatively propagated staple food crops ought to take the evolutionary responses of the virus into consideration. Not doing so leads to a risk of failure, which can result in considerable economic losses and increased poverty. Specifically in vitro propagation, diagnostics and breeding methods carry a risk of failure due to the selection for virus strains that build up a high within-plant virus titre. For vegetatively propagated crops, sanitation by roguing has a low risk of failure owing to its combination of selecting for low virus titre strains as well as increasing healthy crop density. 相似文献
95.
96.
AA Bozzo CA Soñez I Monedero Cobeta A Rolando MC Romanini D Cots 《Biotechnic & histochemistry》2014,89(4):296-303
The model of chronic intermittent stress by immobilization during pregnancy may produce alterations in the mechanisms that maintain adrenal gland homeostasis. In earlier investigations using this model, significant variations in plasma prolactin and corticosterone levels, and adrenal gland weights were observed. We hypothesized that chronic stress causes changes in apoptosis in the adrenal glands of pregnant rats. We identified and quantified apoptotic cells in the adrenal cortex and examined their ultrastructural characteristics using transmission electron microscopy. Adrenal glands of pregnant rats at gestation days 12, 17 and 21 were studied for control and experimental (stressed) rats. Immunolabelling techniques, stereological analysis and image quantification of adrenal gland sections were combined to determine differences in apoptosis in the different cell populations of the adrenal cortex. The apoptotic index of the experimental rats showed a significant reduction at gestation day 17, while at days 12 and 21 there were no differences from controls. Moreover, the apoptotic index of the reticular zones in control and experimental animals showed a significant increase compared to the glomerular and fascicular zones at the three gestation times studied. Chronic stress by immobilization reduced the caspase-dependent apoptotic index at gestation day 17, which may be related to variations in plasma concentrations of estrogens and prolactin. 相似文献
97.
Gilligan PH 《Current opinion in microbiology》2002,5(5):489-495
The events of the autumn of 2001 in the United States made it clear that the spectre of the use of microorganisms to intentionally harm humans is a reality. The current strategy to control disease outbreaks caused by the intentional release of bacteria is to use antimicrobial agents, both therapeutically and prophylactically. However, multidrug-resistant strains of bacterial bioterrorism agents occur naturally or have been bio-engineered, indicating how vulnerable this strategy is. 相似文献
98.
Defining appropriate policies for controlling the spread of fungal disease in agricultural landscapes requires appropriate theoretical models. Most existing models for the fungicidal control of plant diseases do not explicitly include the dynamics of the fungicide itself, nor do they consider the impact of infection occurring during the host growth phase. We introduce a modelling framework for fungicide application that allows us to consider how "explicit" modelling of fungicide dynamics affects the invasion and persistence of plant pathogens. Specifically, we show that "explicit" models exhibit bistability zones for values of the basic reproductive number ([Formula: see text]) less than one within which the invasion and persistence threshold depends on the initial infection levels. This is in contrast to classical models where invasion and persistence thresholds are solely dependent on [Formula: see text]. In addition if initial infection occurs during the growth phase then an additional "invasion zone" can exist for even smaller values of [Formula: see text]. Within this region the system will experience an epidemic that is not able to persist. We further show that ideal fungicides with high levels of effectiveness, low rates of application and low rates of decay lead to the existence of these bistability zones. The results are robust to the inclusion of demographic stochasticity. 相似文献
99.
Cocuzza AJ Chidester DR Culp S Fitzgerald L Gilligan P 《Bioorganic & medicinal chemistry letters》1999,9(7):1063-1066
The Suzuki reaction has been used to synthesize a variety of aryl-substituted heterocyclic antagonists of the CRH1 receptor. Examples with several different heterocyclic cores are potent CRH receptor ligands. 相似文献
100.
J P Beck M A Curry R J Chorvat L W Fitzgerald P J Gilligan R Zaczek G L Trainor 《Bioorganic & medicinal chemistry letters》1999,9(8):1185-1188
A series of thiazolo[4,5-d]pyrimidine thiones and -ones was prepared and discovered to have good binding affinity to the CRH-R1 receptor, thus showing promise as a new class of potential anxiolytics and/or antidepressants. 相似文献