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Infectious full-length cDNA clones from the genomic RNAs of a subgroup II cucumber mosaic cucumovirus strain (Trk7) were obtained. Sequence analysis of the whole genome revealed strong homology (99%) to the genome of Q-CMV, the only subgroup II strain whose entire genomic nucleotide sequence had been available in the database, and an overall 75% homology to those of subgroup I strains. We provide sequence comparisons of different parts of 1a, 2a and 2b proteins of Cucumovirus species, and propose phylogenetic trees based on these protein sequences. 相似文献
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U. Sławin´ska F. Tyc˘ S. Kasicki R. Navarrete G. Vrbová 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(2):193-201
After partial denervation, the remaining motor units (MUs) of adult fast extensor digitorum longus muscle (EDL) expand their
peripheral field. The time course of this event was studied using tension measurement and recordings of electromyographic
(EMG) activity. The results show that after section of the L4 spinal nerve, when only 5.3 ± 0.63 of the 40 MUs normally supplying
EDL muscle remain, the force of individual motor units starts to increase between the 1st and 2nd week after the operation
and continues to do so for a further week. The drastic reduction of the number of motoneurones supplying the fast EDL leads
to an increase in activity of the remaining MUs. In the 1st week after partial denervation, there was a sharp increase in
the EMG activity of remaining motor units. During the next 12 days, this increase became less marked, but EMG activity remained
nevertheless significantly higher than that of the unoperated EDL muscle. Many MUs became tonically active during posture.
The EMG activity pattern during locomotion was also altered, so that the burst duration was positively correlated with the
step cycle duration. Moreover, shortly after partial denervation, the interlimb coordination was disturbed but returned to
its original symmetrical use 1–2 weeks later.
Received: 17 September 1996 / Accepted: 3 November 1997 相似文献
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D. S. Stokic´ W. Barry McKay Lillian Scott Arthur M. Sherwood Milan R. Dimitrijevic´ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(3):437-443
The aim of the present study was to determine the characteristics of intracortical inhibition in the motor cortex areas representing
lower limb muscles using paired transcranial magnetic (TMS) and transcranial electrical stimulation (TES) in healthy subjects.
In the first paradigm (n=8), paired magnetic stimuli were delivered through a double cone coil and motor evoked potentials (MEPs) were recorded from
quadriceps (Q) and tibialis anterior (TA) muscles during relaxation. The conditioning stimulus strength was 5% of the maximum
stimulator output below the threshold MEP evoked during weak voluntary contraction of TA (33±5%). The test stimulus (67±2%)
was 10% of the stimulator output above the MEP threshold in the relaxed TA. Interstimulus intervals (ISIs) from 1–15 ms were
examined. Conditioned TA MEPs were significantly suppressed (P<0.01) at ISIs of less than 5 ms (relative amplitude from 20–50% of the control). TA MEPs tended to be only slightly facilitated
at 9-ms and 10-ms ISIs. The degree of MEP suppression was not different between right and left TA muscles despite the significant
difference in size of the control responses (P<0.001). Also, conditioned MEPs were not significantly different between Q and TA. The time course of TA MEP suppression,
using electrical test stimuli, was similar to that found using TMS. In the second paradigm (n=2), the suppression of TA MEPs at 2, 3, and 4 ms ISIs was examined at three conditioning intensities with the test stimulation
kept constant. For the pooled 2- to 4-ms ISI data, relative amplitudes were 34±6%, 61±5%, and 98±9% for conditioning intensities
of 0.95, 0.90, and 0.85× active threshold, respectively (P<0.01). In conclusion, the suppression of lower limb MEPs following paired TMS showed similar characteristics to the intracortical
inhibition previously described for the hand motor area.
Received: 21 June 1996 / Accepted: 23 May 1997 相似文献
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Gilli F Sala A Bancone C Salacone P Gallo M Gaia E Bertolotto A 《Journal of immunological methods》2002,262(1-2):187-190
Previously, we have reported the development of a new quantitative-competitive polymerase chain reaction (qc-PCR) method to evaluate interferon-beta (IFNbeta) bioavailability in multiple sclerosis (MS) patients, by measuring mRNA of mixovirus resistance protein A (MxA). Here we show that our assay is also able to assess IFNalpha bioavailability in hepatitis C virus (HCV) patients treated with different IFNalpha regimens. Indeed, our method was able to detect a slight constitutive expression of MxA mRNA in untreated HCV patients (median=70 fgMxA/pgGAPDH) and a significant induction 12 h after the first IFNalpha administration (median=750 fgMxA/pgGAPDH). 相似文献
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