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51.
L Vulchanova MS Riedl SJ Shuster LS Stone KM Hargreaves G Buell A Surprenant RA North R Elde 《Canadian Metallurgical Quarterly》1998,10(11):3470-3478
The P2X3 receptor subunit, a member of the P2X family of ATP-gated ion channels, is almost exclusively localized in sensory neurons. In the present study, we sought to gain insight into the role of P2X3 and P2X3-containing neurons in sensory transmission, using immunohistochemical approaches. In rat dorsal root ganglia (DRG), P2X3-immunoreactivity (-ir) was observed in small- and medium-sized neurons. Approximately 40% of DRG neuronal profiles in normal rats contained P2X3-ir. In rats that had received neonatal capsaicin treatment, the number of P2X3-positive neurons was decreased by approximately 70%. Analysis of the colocalization of P2X3-ir with cytochemical markers of DRG neurons indicated that approximately 94% of the P2X3-positive neuronal profiles were labelled by isolectin B4 from Bandeiraea simplicifolia, while only 3% contained substance P-ir, and 7% contained somatostatin-ir. In dorsal horn of rat spinal cord, P2X3-ir was observed in the inner portion of lamina II and was reduced subsequent to dorsal rhizotomy, as well as subsequent to neonatal capsaicin treatment. Finally, P2X3-ir accumulated proximal to the site of sciatic nerve ligation, and was seen in nerve fibres in skin and corneal epithelium. In summary, our results suggest that P2X3 is expressed by a functionally heterogeneous population of BSI-B4-binding sensory neurons, and is transported into both central and peripheral processes of these neurons. 相似文献
52.
NV Tat'ianko LL Gromashevskaia AD Vovk MG Kasatkina OV Liashok VI Matiash SP Iasinovy? IaN Kovgan 《Canadian Metallurgical Quarterly》1996,(5-6):119-122
In this paper, characterization is given of clinical and biochemical features of VH B course against the background of narcomania. Recordable in such patient populations are high percentage of delta hepatitis (14.2%), unusual severity of the intoxication syndrome, protracted course with exacerbations (12.2%) and recurrences (8%), outcome being a chronic hepatitis (14.2%), slower normalization of biochemical indicators, persistently low ratio of AIAT activity in diluted and whole blood sera. The persistence of viral markers in drug addicts discharged from the hospital (68%) is fraught with danger of spreading viral hepatitis of prophylactic measures are not strictly observed. 相似文献
53.
JM Rabey H Bass U Bonuccelli D Brooks P Klotz AD Korczyn P Kraus P Martinez-Martin P Morrish W Van Sauten B Van Hilten 《Canadian Metallurgical Quarterly》1997,20(4):322-337
The extensive use of the Unified Parkinson's Disease Rating Scale (UPDRS) has revealed low interrater reliability in some items and redundancy in others. In view of these shortcomings, we have structured a new scale that includes a zero-to three-point scale for each item in the evaluation of PD. The mental axis includes memory, thought disorders, and depression. Activities of daily living (ADL) includes eight items: speech, eating, feeding, dressing, hygiene, handwriting, walking, and turning in bed. The motor examination includes eight items: speech, tremor, rest and posture, rigidity, finger tapping, arising from chair, gait, and postural stability. Complications of therapy were also included: dyskinesias, dystonia, motor fluctuations, and freezing episodes, collected by history. In addition, a global scoring for motor fluctuations that should complement the Hoehn and Yahr Scale was incorporated. In this report, we present a statistical analysis of the ADL, motor evaluation, and complications of therapy sections. Concerning the interrater reliability mean, Kendall's W values were >0.9 for most of the items in the Short Parkinson's Evaluation Scale (SPES). Kendall's W <0.8 (motor evaluation) was found for two items of the SPES and nine items of the UPDRS. The mean interrater reliability for both scales across all seven centers (seven Kendall's W for seven centers) (Mann-Whitney test) showed no statistical differences between the scales. Spearman's correlations between items of both scales were significant. Factor analysis of the SPES and UPDRS data revealed a four-factor solution that explained approximately 60% of the data. All participating centers found the SPES easier to apply and quicker to complete, when compared with the UPDRS. The results obtained strongly favor the introduction of SPES for clinical practice. 相似文献
54.
The development and capabilities of a prototype expert system that provides real-time spacecraft system analysis and command generation are described. At present, ESSOC (Expert System for Satellite Orbit Control) is capable of performing the stationkeeping maneuver for a geostationary satellite. ESSOC guides the operator through the stationkeeping operation by recommending appropriate commands that reflect both the changing spacecraft condition and previous procedural action. Information regarding satellite status is stored in a knowledge base internal to the expert system. This knowledge base is continuously updated with processed spacecraft telemetry. Information on the procedural structure is encoded in production rules. The independence of the procedural rules from each other, and from the knowledge base, makes the system easy to maintain and expand. Particular attention is directed to distinctive features of the ESSOC system and its development, namely, the structured methods of knowledge acquisition, and the design and performance-enhancing techniques that enable ESSOC to operate in a real-time environment. 相似文献
55.
H. E. N. Stone 《Journal of Materials Science》1992,27(6):1701-1703
Ten samarium-structure alloys have been oxidation tested in air to estimate the thermal oxidation parameter, T
p, and hence the ratio T
p/TSm, where T
Sm is the temperature of decomposition of the appropriate structure and the ratio is a measure of the strength and type of bonding. The ratio decreases with (a) increasing distance apart in the 4f series of the components, and (b) increasing average Group number. 相似文献
56.
57.
H Reznik-Wolf TA Treves M Davidson J Aharon-Peretz PH St George Hyslop J Chapman AD Korczyn B Goldman E Friedman 《Canadian Metallurgical Quarterly》1996,98(6):700-702
Germline mutations in the presenilin 1 (PS1) gene apparently account for the majority of early-onset, familial Alzheimer's disease (AD). Using a mutation-screening strategy (denaturing gradient gel electrophoresis; DGGE), we analyzed a large family with early onset AD and seizures. The patients in this family showed a novel missense mutation in exon 5 of the PS1 gene (A to T change in codon 120, altering glutamine to aspartic acid). This novel mutation is located within the second hydrophilic domain of the molecule, a region not particularly involved in previously described germline mutations, and is of unknown biological significance. These results also demonstrate that DGGE can be used effectively to screen for mutations within this gene. 相似文献
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Aortic valve endocarditis commonly leads to the formation of a root abscess, but fistulae are uncommon. The echocardiographic findings in a patient with Streptococcus viridans endocarditis of a prosthetic aortic valve associated with a fistula between the aorta and the left atrium are presented. The diagnosis was made by transthoracic echocardiography, although the transesophageal study gave higher resolution views and allowed a more confident exclusion of mitral valve involvement. 相似文献