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991.
Respiratory syncytial virus and other pneumoviruses: a review of the international symposium--RSV 2003 总被引:3,自引:0,他引:3
Schmidt AC Johnson TR Openshaw PJ Braciale TJ Falsey AR Anderson LJ Wertz GW Groothuis JR Prince GA Melero JA Graham BS 《Virus research》2004,106(1):1-13
The Respiratory Syncytial Virus 2003 symposium took place from 8th-11th November 2003 in Stone Mountain, Georgia, and brought together more than 200 international investigators engaged in RSV research. RSV biology, pathogenesis, and clinical data, as well as RSV vaccines and antivirals, were addressed in the meeting, and this review will aim to briefly summarize and discuss the implications of new findings. The meeting also served as the inauguration of the Robert M. Chanock Award for lifetime achievement in RSV research, an award named in honor of the person who started the field of RSV research by recovering the first human RS virus from infants with severe bronchiolitis in 1956. 相似文献
992.
Kinnard L Lo SC Makariou E Osicka T Wang P Chouikha MF Freedman MT 《Medical physics》2004,31(10):2796-2810
Our purpose in this work was to develop an automatic boundary detection method for mammographic masses and to rigorously test this method via statistical analysis. The segmentation method utilized a steepest change analysis technique for determining the mass boundaries based on a composed probability density cost function. Previous investigators have shown that this function can be utilized to determine the border of the mass body. We have further analyzed this method and have discovered that the steepest changes in this function can produce mass delineations that include extended projections. The method was tested on 124 digitized mammograms selected from the University of South Florida's Digital Database for Screening Mammography (DDSM). The segmentation results were validated using overlap, accuracy, sensitivity, and specificity statistics, where the gold standards were manual traces provided by two expert radiologists. We have concluded that the best intensity threshold corresponds to a particular steepest change location within the composed probability density function. We also found that our results are more closely correlated with one expert than with the second expert. These findings were verified via Analysis of Variance (ANOVA) testing. The ANOVA tests obtained p-values ranging from 1.03 x 10(-2)-7.51 x 10(-17) for the single observer studies and 2.03 x 10(-2)-9.43 x 10(-4) for the two observer studies. Results were categorized using three significance levels, i.e., p<0.001 (extremely significant), p <0.01 (very significant), and p <0.05 (significant), respectively. 相似文献
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The purpose of this study was to characterize the transtympanically evoked, perioperative electrically evoked auditory brainstem response (EABR) and define its relationship with preoperative hearing, age and hearing loss etiology in 59 children (10-60 months of age) who had received cochlear implants. The results indicate that there was no difference between wave V latency obtained from the younger (10-36 months) and the older (37-60 months) children. There was a statistically significant difference in the preoperative pure-tone average between the higher-EABR threshold group (650 microA and above) and the lower-EABR threshold group (600 microA or less). Patients with post-meningitic deafness exhibited the longest EABR wave V latencies. Perioperative, transtympanic, promontory EABR is an effective clinical procedure which can decrease the likelihood of placing a cochlear implant in a non-stimulable ear, and may provide the clinician with a valuable tool for selecting the most appropriate ear for implantation. 相似文献
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997.
Fibrocartilaginous embolism is a rare cause of spinal cord infarction. It is postulated that an acute vertical disk herniation of the nucleus pulposus material can lead to spinal cord infarction by a retrograde embolization to the central artery. An increased intradiskal pressure resulting from axial loading of the vertebral column with a concomitant Valsalva maneuver is thought to be the initiating event for the embolus. We present a previously healthy 16-year-old boy with sudden onset of back pain and progressive paraparesis within 36 hours after lifting exercises in a squat position. His clinical presentation and neuroimaging studies were consistent with spinal cord infarction resulting from a central artery embolus at the T8 spinal cord level. Laboratory investigation showed no evidence of infectious, autoimmune, inflammatory, or neoplastic causes. Although no histologic confirmation was obtained, lack of evidence for other plausible diagnoses in the setting of his clinical presentation and in the magnetic resonance imaging findings made fibrocartilaginous embolism myelopathy the most likely diagnosis. We postulated that some cases of transverse myelitis might actually be fibrocartilaginous embolism, making it a more prevalent cause of an acute myelopathy than commonly recognized. Relevant literature and current theories regarding the pathogenesis of fibrocartilaginous embolism myelopathy are reviewed. 相似文献
998.
Interaction between dinucleotide and nicotinic receptors in individual cholinergic terminals 总被引:4,自引:0,他引:4
Díaz-Hernández M Sánchez-Nogueiro J Pintor J Miras-Portugal MT 《The Journal of pharmacology and experimental therapeutics》2004,311(3):954-967
Functional ionotropic nucleotidic receptors responding to diadenosine pentaphospate and nicotinic receptors responding to epibatidine coexpress in 19% of the total rat midbrain cholinergic terminals, as determined by the combination of immunological and microfluorimetric techniques. Activation of each independent receptor induces the intrasynaptosomal [Ca2+]i and acetylcholine (ACh) release in a dose-dependent way. The responses are inhibited by antagonists of the dinucleotide receptor and nicotinic receptors, thus confirming the involvement of specific receptors in both functions. Stimulation of single cholinergic terminal with both agonists altogether results in a significant decrease of the [Ca2+]i signaling compared with responses of each independent agonist. Inhibitory interaction between both receptors is reverted when one of them is blocked by specific antagonists, both in [Ca2+]i, and subsequent ACh release. The receptor's inhibitory cross talk confirm the involvement of calcium/calmodulin-dependent protein kinase II, CaMKII, as the inhibitory effects are reverted in the presence of the specific inhibitors KN-62 (2-[N-(4'-methoxybenzenesulfonyl)]-amino-N-(4'-chlorophenyl)-2-propenyl-N-methylbenzylamine phosphate) and KN-93 (N-(2-[N-[4-chlorocinnamyl]-N-methylaminomethyl]phenyl)-N-(2-hydroxyethyl)-4-methoxybenzenesulphonamide). These results demonstrate the existence of an efficient interaction between these two channel populations, opening a new understanding of the functioning of the cholinergic synaptic terminals or terminals containing other neurotransmitters but exhibiting these receptor types or ones that are similar. 相似文献
999.
Chemotherapy is keeping more and more patients alive, but its side effects can be debilitating. Appropriate nursing care and education can help cancer patients overcome the challenges of this vital treatment. 相似文献
1000.
Local genetic patterns within a vancomycin-resistant Enterococcus faecalis clone isolated in three hospitals in Portugal 下载免费PDF全文
Novais C Coque TM Sousa JC Baquero F Peixe L;Portuguese Resistance Study Group 《Antimicrobial agents and chemotherapy》2004,48(9):3613-3617
Eight pulsed-field gel electrophoresis subtypes and six Tn1546 variants were identified among Enterococcus faecalis isolates of a single clone recovered in three geographically separate Portuguese hospitals. Some clonal subtypes were found in particular hospitals, and Tn1546 variants were either widespread or confined to some of them. We also report on the first Tn1546 transposon containing an ISEf1 insertion. 相似文献