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1.
《Cell reports》2020,30(4):1152-1163.e4
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2.
《Cell reports》2020,30(1):164-172.e4
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3.
The photon flux autocorrelation function of a fluorescent label attached to a bacterial motor shaft is calculated for the case in which the bacterial motor is considered to be actively but idly rotating. It is shown that even when the fluorescent label has a very short lifetime, fluorescence correlation spectroscopy should provide a useful tool for determining the rate of revolution of the bacterial motor under various solution conditions. 相似文献
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Abstract Both the intracellular and the extracellular concentration of cyclic AMP increases logarithmically in synchronously growing cultures of Escherichia coli . Thus, cyclic AMP by itself cannot regulate growth and division of the bacterium during the cell cycle. 相似文献
6.
P. Gerrans 《Biology & philosophy》2007,22(1):35-56
Delusions are currently characterised as false beliefs produced by incorrect inference about external reality (DSM IV). This
inferential conception has proved hard to link to explanations pitched at the level of neurobiology and neuroanatomy. This
paper provides that link via a neurocomputational theory, based on evolutionary considerations, of the role of the prefrontal
cortex in regulating offline cognition. When pathologically neuromodulated the prefrontal cortex produces hypersalient experiences
which monopolise offline cognition. The result is characteristic psychotic experiences and patterns of thought. This bottom-up
account uses neural network theory to integrate recent theories of the role of dopamine in delusion with the insights of inferential
accounts. It also provides a general model for evolutionary psychiatry which avoids theoretical problems imported from evolutionary
psychology. 相似文献
7.
《Neuron》2020,105(6):1062-1076.e6
8.
Abstract A short-term oral administration of live Saccharomyces cerevisiae cells, strain Sillix Hansen DSM 1883, resulted in enhanced resistance of mice toward infections with K. pneumoniae, S. pneumoniae and S. pyogenes A produced by intranasal inoculation. Yeast pre-treatment also increased the efficacy of antibiotic therapy in bacterial infections and of antiviral drugs in viral infections. Yeast treatment of animals stimulated phagocytosis, activated the complement system and induced interferon which are likely to represent the main mechanisms of action whereby pretreatment of mice with live S. cerevisiae cells increases resistance to infection. It is concluded that preventive administration of live Saccharomyces cerevisiae cells should be used for increasing resistance to bacterial infections, in particular of the respiratory tract, or to viral infections, as well as an adjunct to antibiotic and antiviral drug therapy. 相似文献
9.
Summary . We propose a fully inferential model-based approach to the problem of comparing the firing patterns of a neuron recorded under two distinct experimental conditions. The methodology is based on nonhomogeneous Poisson process models for the firing times of each condition with flexible nonparametric mixture prior models for the corresponding intensity functions. We demonstrate posterior inferences from a global analysis, which may be used to compare the two conditions over the entire experimental time window, as well as from a pointwise analysis at selected time points to detect local deviations of firing patterns from one condition to another. We apply our method on two neurons recorded from the primary motor cortex area of a monkey's brain while performing a sequence of reaching tasks. 相似文献
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