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Gauthier Janel Lacroix Renée Coté Alain Doyon Julien Drolet Michel 《Applied psychophysiology and biofeedback》1985,10(2):139-159
In order to assess the relative effectiveness of finger warming and temporal blood volume pulse reduction biofeedback in the treatment of migraine, 22 female migraine patients were assigned to one of three experimental conditions: temporal artery constriction feedback, finger temperature feedback, or waiting list. Biofeedback training consisted of 12 sessions over a 6-week period. All patients completed 5 weeks of daily self-monitoring of headache activity (frequency, duration, and intensity) and medication before and after treatment. Treatment credibility was assessed at the end of Sessions 1, 6, and 12. Results showed that temporal constriction and finger temperature biofeedback were equally effective in controlling migraine headaches and produced greater benefits than the waiting list condition. Power analyses indicated that very large sample sizes would have been required to detect any significant differences between the two treatment groups. No significant relationships were found between levels of therapeutic gains and levels of thermal or blood volume pulse self-regulation skills. Likewise, treatment outcome was not found to be related to treatment credibility. Further analyses revealed that changes in headache activity and medication were associated with changes in vasomotor variability. Because blood volume pulse variability was not significantly affected by biofeedback training, questions about its role in the therapeutic mechanism are raised.This research was supported in part by grants from the Quebec Ministry of Education and the Quebec Ministery of Social Affairs to the first author, and an award from the Medical Research Council of Canada to the second author. The authors are indebted to Drs. Frank Andrasik, Howard Barbaree, Edward Blanchard, Martin Ford, and Patrick McGrath, as well as to two anonymous reviewers, for their helpful comments on an earlier draft of this paper. 相似文献
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Detection of truncated virus particles in a persistent RNA virus infection in vivo. 总被引:2,自引:0,他引:2 下载免费PDF全文
Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus which causes devastating epizootics of trout and salmon fry in hatcheries around the world. In laboratory and field studies, epizootic survivors are negative for infectious virus by plaque assay at about 50 days postexposure. Survivors are considered virus free with no sequelae and, thus, are subsequently released into the wild. When adults return to spawn, infectious virus can again be isolated. Two hypotheses have been proposed to account for the source of virus in these adults. One hypothesis contends that virus in the epizootic survivors is cleared and that the adults are reinfected with IHNV from a secondary source during their migration upstream. The second hypothesis contends that IHNV persists in a subclinical or latent form and the virus is reactivated during the stress of spawning. Numerous studies have been carried out to test these hypotheses and, after 20 years, questions still remain regarding the maintenance of IHNV in salmonid fish populations. In the study reported here, IHNV-specific lesions in the hematopoietic tissues of rainbow trout survivors, reared in specific-pathogen-free water, were detected 1 year after the epizootic. The fish did not produce infectious virus. The presence of viral protein detected by immunohistochemistry, in viral RNA by PCR amplification, and in IHNV-truncated particles by immunogold electron microscopy confirmed the presence of IHNV in the survivors and provided the first evidence for subclinical persistence of virus in the tissues of IHNV survivors. 相似文献
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目的:探讨MR弥散加权成像(DWI)鉴别诊断良恶性椎体压缩性骨折的临床价值。方法:对57例经临床或病理证实的椎体良恶性压缩性骨折患者行矢状位T1M、T2WI、T2WI/FS及DWI扫描,研究其在常规序列和DWI序列上的表现,将常规MR序列和DWI序列检出率进行比较,测量正常椎体及病变椎体的表观弥散系数(ADC)值,并进行统计学分析。结果:(1)MR常规序列和DWI序列(b=500s/mm2)表现:良性椎体压缩性骨折呈长T1长或等T2改变,T2WI/FS呈高信号,DWI可以呈高信号、等信号及低信号;恶性椎体压缩性骨折呈长T1长T2信号,大部分病灶T2WUFS及DWI呈高信号,少数变现为低信号;(2)MR常规序列和DWI序列(b=500s/mm2)病灶检出率的比较:T1WI、T2WI/FS及DWI序列病灶检出率均高于T2WI序列,其间的差别有显著性意义(P〈0.01),T1WI、T2WI/FS及DWI序列病灶检出率之间无显著性差异(P〉0.01);(3)ADC值比较:在DWI(b=500s/mm2)上,良性组ADC值为(2.03±0.83)×10^3mm^2/s,恶性组ADC值为(1.37±0.75)×10^-3mm^2/s,正常组ADC值为(0.36±0.21)×10^-3mm^2/s,成像条件相同时,良性组高于恶性组,两组间有明显的统计学意义(P〈0.05)。结论:DWI可较好的反映椎体的弥散特征,ADC值作为量化指标可对良恶性椎体压缩性骨折进行可靠鉴别。 相似文献
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Larson Boundenga Boris Makanga Benjamin Ollomo Aude Gilabert Virginie Rougeron Bertrand Mve-Ondo Céline Arnathau Patrick Durand Nancy Diamella Moukodoum Alain-Prince Okouga Lucresse Delicat-Loembet Lauriane Yacka-Mouele Nil Rahola Eric Leroy Cheikh Tidiane BA Francois Renaud Franck Prugnolle Christophe Paupy 《PloS one》2016,11(2)
Re-examination, using molecular tools, of the diversity of haemosporidian parasites (among which the agents of human malaria are the best known) has generally led to rearrangements of traditional classifications. In this study, we explored the diversity of haemosporidian parasites infecting vertebrate species (particularly mammals, birds and reptiles) living in the forests of Gabon (Central Africa), by analyzing a collection of 492 bushmeat samples. We found that samples from five mammalian species (four duiker and one pangolin species), one bird and one turtle species were infected by haemosporidian parasites. In duikers (from which most of the infected specimens were obtained), we demonstrated the existence of at least two distinct parasite lineages related to Polychromophilus species (i.e., bat haemosporidian parasites) and to sauropsid Plasmodium (from birds and lizards). Molecular screening of sylvatic mosquitoes captured during a longitudinal survey revealed the presence of these haemosporidian parasite lineages also in several Anopheles species, suggesting a potential role in their transmission. Our results show that, differently from what was previously thought, several independent clades of haemosporidian parasites (family Plasmodiidae) infect mammals and are transmitted by anopheline mosquitoes. 相似文献
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van der Veen BA Uitdehaag JC Dijkstra BW Dijkhuizen L 《Biochimica et biophysica acta》2000,1543(2):336-360
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Mélanie Drolet Marc Brisson Kenneth E. Schmader Myron J. Levin Robert Johnson Michael N. Oxman David Patrick Caty Blanchette James A. Mansi 《CMAJ》2010,182(16):1731-1736