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81.
BackgroundAutoimmune hepatitis is a chronic inflammatory disease, the abnormal immunological function is the main pathogenesis. Interleukin-34 is a newly identified cytokine that shares the same receptor as colony stimulating factor-1.MethodsWe used interleukin-34 knockout and wild-type mice in a Con A-induced hepatitis model and cocultured RAW264.7 macrophage cells with interleukin-34. We then detected associated inflammatory cytokine and chemokine levels to elucidate the role of interleukin-34.ResultsIn this study, we found that the loss of interleukin-34 resulted in higher sensitivity to Con A-induced hepatitis. RAW264.7 macrophage cells were able to differentiate to the M2 phenotype upon interleukin-34 stimulation.ConclusionsWe conclude that interleukin-34 may protect the liver from Con A-mediated hepatitis by driving M2 macrophage polarization and suppressing inflammation. 相似文献
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Hajnal Jolsvai Elyse Sussman Roland Csuhaj Valéria Csépe 《International journal of psychophysiology》2011,82(3):207-216
Non-adjacent dependencies are thought to be more costly to process than sentences wherein dependents immediately follow or precede what they depend on. In English locality effects have been revealed, while in languages with rich case marking (German and Hindi) sentence final structures show anti-locality-effects. The motivation of the current study is to test whether locality effects can be directly applied to a typologically different language than those investigated so far. Hungarian is a “topic prominent” language; it permits a variation of possible word sequencing for semantic reasons, including SVO word order. Hungarian also has a rich morphological system (e.g., rich case system) and postpositions to indicate grammatical functions. In the present ERP study, Hungarian subject–verb dependencies were compared by manipulating the mismatch of number agreement between the sentence's initial noun phrase and the sentence's final intransitive verb as well as the complexity of the intervening sentence material, interrupting the dependencies. Possible lexical class and frequency or cloze-probability effects for the first two words of the intervening sentence material were revealed when used separate baseline for each word, while at the third word of the intervening material as well as at the main verb ERPs were not modulated by complexity but at the verb ERPs were enhanced by grammaticality. Ungrammatical sentences enlarged the amplitude of both LAN and P600 components at the main verb. These results are in line with studies suggesting that the retrieval of the first element of a dependency is not influenced by distance from the second element, as the first element is directly accessible when needed for integration (e.g., McElree, 2000). 相似文献
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《Clinical neurophysiology》2014,125(1):108-123
ObjectivesAutism spectrum disorder (ASD) is characterized by impaired global language processing, whereas local language processing often appears intact. Recent psycholinguistic research suggests that the quality of language perception relies on monitoring, an aspect of executive control. The aim of the study was to examine monitoring in people with ASD of (a) local, orthographic violations, and (b) global, syntactic violations, when provided with single level versus dual level task instructions.MethodsWe recorded event-related potentials and compared P600 effects to the linguistic violations relative to correct words in 14 adults with ASD and 14 matched controls.ResultsIn control participants, local errors elicited a monitoring response as tapped by the P600 effect in both conditions. For global errors, the P600 effect was present only at one centroposterior site in the single level condition, whereas in the dual level condition a broadly distributed effect was obtained. People with ASD, however, showed a monitoring response to local and global errors both in the single and dual level condition.ConclusionsThe main ERP finding suggests that when instructed people with ASD monitor global aspects of language already under simple circumstances, whereas people without ASD mainly do so under more complex circumstances.SignificanceResults suggest that language problems in ASD should not be studied in terms of a linguistic dysfunction as such, but in light of the use of executive resources during language comprehension. 相似文献
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David Pye Peter Herse Ha Nguyen Lan Vuong Quoc Pham 《Clinical & experimental optometry》1999,82(1):11-13
Background : Clinical experience has shown that the sensitivity indices reported by the Humphrey Field Analyser (HFA) are generally higher than those given by the Medmont Automated Perimeter (M600). It is the purpose of this paper to determine a conversion factor for the two perimeters and to confirm this prediction using clinical data. Theory predicted that HFAsensitivity ? 5 dB = M600sensitivity. Methods : Sensitivity versus eccentricity profiles were measured over the central visual field on 10 young subjects using both perimeters. Results : Both the HFA and the M600 operate within the realms of the Weber law and measure similar Weber fractions. The sensitivity profiles had similar slopes (about ?0.2 dB/degree) and were separated by about six decibels with the HFA reporting higher sensitivity values. This result confirmed the theoretical prediction. Conclusion : The difference in threshold sensitivities between the two perimeters is a result of differences in scaling factors and instrument luminances. A suggested clinical conversion factor is to subtract 5 dB from the HFA data to approximate those of the M600. 相似文献
89.
Slow Ca and K currents across frog skeletal muscle membrane were recorded with the Vaseline gap voltage clamp in order to investigate block by divalent cations and various organic compounds. Cd2+, Ni2+, Co2+, Mn2+, Mg2+ all block Ca currents, as do barbiturates, D-600 and nifedipine. Local anesthetics also block Ca currents, with the impermeant quaternary lidocaine derivative, QX-314, being more than an order of magnitude less potent than its permeant parent compound. Surprisingly, all agents that blocked Ca currents also blocked the slow K currents. To explain this pharmacologic parallel, one could suggest that K current is activated by Ca2+ appearing in the myoplasm due to the combination of Ca current and release from internal stores. While possibly correct for intact fibres, this hypothesis appears not to apply in our case where the myoplasm contained the Ca chelator EGTA at high concentration. Instead, K currents seem to be activated by a decrease in external [Ca2+]. In the transverse tubules, Ca current is known to cause [Ca2+] to decline to submicromolar concentrations, and evidence is presented that K currents are activated by Ca depletion from a restricted extracellular space. It is suggested that K currents flow through Ca channels that have become capable of passing monovalent cations after the tubules have become depleted of Ca2+. 相似文献
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The authors review psychiatric complications of thyroid disease and the use of psychotropic agents in hyper- and hypothyroid patients. Neuropsychiatric symptoms of hyperthyroidism tend to resolve with treatment of excessive thyroid production; those of hypothyroidism respond in a variable manner to thyroid replacement, but most patients improve substantially after becoming euthyroid. The judicious use of most psychotropics has its place even in the presence of overt thyroid disease. The important antithyroid effects of lithium should be noted when treating patients with thyroid disease. Routine monitoring of thyroid function in otherwise healthy patients taking antipsychotic agents, tricyclic antidepressants, or monoamine oxidase inhibitors (MAOIs) is not believed necessary. 相似文献