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51.
The present experiments were carried out to determine the effects of energy deposition from energetic iron (56Fe particles, an important component of cosmic rays) on motor behavioral performance and to determine if the observed deficits were caused by alterations in the neostriatum (an important motor control area). Neostriatal function was assessed with two correlated parameters, i.e., motor behavioral performance (wire suspension task), and oxotremorine-enhanced K(+)-evoked release of dopamine from perifused striatal slices. Rats were exposed to one of several doses of 56Fe-particle irradiation (0.10-1.0 Gy) and tested on a wire suspension task at 3-180 days postirradiation. Results indicated that profound decrements occurred in both of these indices. The effects on K(+)-evoked release of dopamine were evident for as long as 180 days after irradiation, and a subsequent experiment indicated that these effects appeared as early as 12 h postirradiation. Since similar findings have been observed in aged rats, the results are discussed in terms of these particles producing a possible accelerated striatal aging effect. 相似文献
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K N Chengappa R Ganguli Z W Yang G Schurin J Cochran J S Brar B Rabin 《Life sciences》1992,51(24):1843-1849
Using a laterality questionnaire, 138 normal healthy individuals were classified as right-sided and 25 as non-right sided. Interleukin-2 (IL-2) was generated from whole blood obtained from these subjects using mitogen (PHA) stimulation. IL-2 was quantitated in picograms/ml using an enzyme immunoassay (ELISA). Additionally, sera from these subjects were tested for 7 autoantibodies by standard serological methods. As compared to right sided subjects, non-right sided individuals had significantly lower IL-2 production. Non-right sided individuals with autoantibodies had significantly lower IL-2 production than right sided subjects with or without autoantibodies, but did not differ significantly from their non-right sided counterparts without autoantibodies. These data support the increasing evidence for the differential and lateralized regulation of immune functions by the right and left cerebral regions. 相似文献
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Sankarsan Roy Susanta Kumar Chakraborty Panchanan Parui Bulganin Mitra 《Proceedings of the Zoological Society》2018,71(2):121-126
The present communication deals with recording of nine species of soldier flies (Insecta: Diptera: Stratiomyidae) from Sunderban Biosphere Reserve of India, of which, Tinda indica (Walker, 1851), Hermetia illucens (Linnaeus, 1758), Odontomyia kashmirensis Brunetti, 1920, Odontomyia viridana (Wiedemann, 1824), Prosopochrysa vitripennis (Doleschall, 1856) are being reported for the first time from this unique and globally acclaimed mangrove ecosystem. Odontomyia kashmirensis Brunetti, 1920 is reported for the first time from the state of West Bengal. A key to identify these species is provided with taxonomic notes. 相似文献
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Inhibition of yeast alcohol dehydrogenase by alkylating agents 总被引:2,自引:0,他引:2
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A characterization of the low temperature structural transition of Escherichia coli 5 S RNA by partial enzymatic digestion 总被引:4,自引:0,他引:4
The low temperature structural transition (low leads to high) of 5 S RNA from Escherichia coli is investigated by partial digestion with ribonuclease T1. In addition to a general masking of guanines from the nuclease, differential changes of accessibility are observed when Mg2+ and salt concentrations are increased to bring about the low leads to high transition. Residue G13 becomes more exposed in the high form while residues G54, G56, G61, G72, and G83-86 become less exposed. The observed cutting rate at other sites is unchanged. A possible conformational change is discussed which could explain the observed changes in RNase T1 digestion patterns as well as the physical chemical observations. 相似文献
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