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Eleven mumps vaccine strains, all containing live attenuated virus, have been used throughout the world. Although L-Zagreb mumps vaccine has been licensed since 1972, only its partial nucleotide sequence was previously determined (accession numbers , and ). Therefore, we sequenced the entire genome of L-Zagreb vaccine strain (Institute of Immunology Inc., Zagreb, Croatia). In order to investigate the genetic stability of the vaccine, sequences of both L-Zagreb master seed and currently produced vaccine batch were determined and no difference between them was observed. A phylogenetic analysis based on SH gene sequence has shown that L-Zagreb strain does not belong to any of established mumps genotypes and that it is most similar to old, laboratory preserved European strains (1950s-1970s). L-Zagreb nucleotide and deduced protein sequences were compared with other mumps virus sequences obtained from the GenBank. Emphasis was put on functionally important protein regions and known antigenic epitopes. The extensive comparisons of nucleotide and deduced protein sequences between L-Zagreb vaccine strain and other previously determined mumps virus sequences have shown that while the functional regions of HN, V, and L proteins are well conserved among various mumps strains, there can be a substantial amino acid difference in antigenic epitopes of all proteins and in functional regions of F protein. No molecular pattern was identified that can be used as a distinction marker between virulent and attenuated strains.  相似文献   
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We measured brain activity using magnetoencephalography in five participants during ongoing tasks that included prospective memory, retrospective memory, and oddball trials. Sources were identified in the hippocampal formation and posterior parietal and frontal lobes. Posterior parietal cortex activation had an earlier onset in the prospective memory condition than retrospective memory or oddball conditions, a higher level of theta activity in the retrospective condition, and higher levels of upper alpha in the prospective and oddball conditions. Activation of the hippocampal formation had a longer duration in the retrospective memory and prospective memory conditions than the oddball condition, but prominent alpha and theta band activity was present in all three conditions. We interpret the early (87 ms) onset of activity in parietal cortex as evidence for an initial noticing of appropriate conditions for a PM response. Hippocampal activity may reflect a subsequent memory search for the intended action.  相似文献   
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We investigated a short pain-provoked head-up tilt (PP-HUT) and the Calgary Syncope Symptom Score in a group of patients with clinically diagnosed vasovagal syncope and group of neurological patients without transient loss of consciousness. We included 127 consecutive patients who were investigated in our laboratory. The group 1 included 56 patients who after appropriate investigations were diagnosed with vasovagal syncope. The group 2 included 70 neurological patients without transient loss of consciousness. The subjects were tilted to 70° for a maximum period of 10 min or until symptoms occurred. If there were no symptoms after initial 10 min, a painful stimulus with the insertion of 0.7 mm needle into the dorsum of hand subcutaneously for 30 s was performed with the patient in the tilted for further 5 min. Calgary Syncope Symptom Score was calculated for all patients. In the group 1, significantly higher number of patients had positive results on PP-HUT (36 vs. 6 patients, respectively; p < 0,001). There was no difference in the presence of orthostatic hypotension (8 vs. 15 patients, respectively; p = 0.36) or postural orthostatic tachycardia syndrome (3 vs. 1 patient, respectively; p = 0.32) between groups. PP-HUT had sensitivity of 65.9 % (95 % CI 0.49–0.79) and specificity of 89.7 % (95 % CI 0.75–0.97). The CSSS had sensitivity of 58.5 % (95 % CI 0.42–0.73) and specificity of 46.1 % (95 % CI 0.30–0.63). PP-HUT has a higher diagnostic rate than the CSSS and provides a rapid alternative to conventional methods.  相似文献   
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BackgroundThe aim of this study was to determine if there is a difference in the frequency of postural orthostatic tachycardia syndrome (POTS) in patients with multiple sclerosis (MS) compared to patients with symptoms of orthostatic intolerance and with no evidence of MS or other neurological illness.MethodsWe analyzed data gathered from 293 patients who underwent the head-up tilt table test protocol. Group 1 included prospectively analyzed 112 with MS and group 2 included retrospectively analyzed 181 patients who were evaluated because of symptoms of orthostatic intolerance, and with no evidence of MS or other neurological illness. If POTS was identified the head-up tilt table test was repeated and supine as well as standing serum epinephrine and norepinephrine were determined.ResultsPOTS was identified in 39 patients: 21 (19%) in the MS group comparing to 18 (10%) in the non MS group (p = 0.035). There was no difference between groups in the occurrence of POTS associated syncope (p = 0.52). There was no difference between groups in the epinephrine or norepinephrine in supine and standing positions. While both standing epinephrine and norepinephrine levels were significantly higher compared to levels in the supine position in the non MS group, only standing norepinephrine levels were significantly higher in the MS group.ConclusionsThe results of this study suggest that POTS is associated with MS.  相似文献   
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This paper presents a conjugate gradient‐based algorithm for feedback min–max optimal control of nonlinear systems. The algorithm has a backward‐in‐time recurrent structure similar to the back propagation through time (BPTT) algorithm. The control law is given as the output of the one‐layer NN. Main contribution of the paper includes the integration of BPTT techniques, conjugate gradient methods, Adams method for solving ODEs and automatic differentiation, to provide an effective, numerically robust algorithm for solving optimal min–max control problems. The proposed algorithm is evaluated on a robotic system with two DOFs. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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BackgroundThe National Institute for Health and Clinical Excellence (NICE) guidelines for multiple sclerosis (MS) recommend the time from initial presentation to first neurological evaluation to be no longer than 6 weeks, and a further 6 weeks until any necessary investigations are completed. The aim of this study was to evaluate how many patients with MS are diagnosed within the NICE timelines in two settings specific for Croatia.Patients and methodsAll patients with the final diagnosis of clinically isolated syndrome (CIS) or MS in a 6 months period were retrospectively reviewed. We calculated time from first symptom to first neurological evaluation, time from first symptom to MRI scan, time from first neurological evaluation to MRI scan, time from first neurological evaluation to lumbar puncture (LP), time from first symptom to diagnosis and time from first neurological evaluation to diagnosis. We also calculated the percentage of patients fulfilling the NICE timelines.ResultsThis study showed that only 61.5% of MS patients in Croatia see neurologist within 6 weeks of first symptoms, and 64.1% are diagnosed within next 6 weeks. However, 80% and 100% of patients presented to the emergency room of our hospital (where a visit to a MS clinic can be automatically made) met the NICE guidelines for time from first symptom to first neurological evaluation and time from first neurological evaluation to diagnosis, respectively.ConclusionA specifically designed demyelinating disease diagnostic clinic offers a better service than other existing models in the diagnosis and management of MS patients.  相似文献   
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Cytoprotector amifostine (AMI) was given in a dose of 50, 100 or 150?mg/kg ip in rats treated with several highly toxic doses of T-2 toxin. The best survival rate (24?h and 7?days after treatment) was obtained with AMI50 (50?mg/kg ip). After T-2 intoxication, a peak in the mean number of gastric lesions (petechiae and ulcerations) was reached on the third day (26.40?±?6.24). Administration of AMI50 reduced, almost completely, the total number of gastric lesions in rats acutely poisoned by 0.5 LD50 T-2 (1.5?mg/kg sc), starting with day 1 after intoxication (5.60?±?3.42).  相似文献   
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