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101.
Maturo VG; Zusmer NR; Gilson AJ; Smoak WM; Janowitz WR; Bear BE; Goddard J; Dick DE 《Radiology》1980,137(2):457-463
Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented. 相似文献
102.
Jay WI Wijesinghe RS Dolasinski BD Roth BJ 《Medical & biological engineering & computing》2012,50(7):651-657
The action currents of a dendrite, peripheral nerve or skeletal muscle create their own magnetic field. Many investigators have attempted to detect neural and dendritic currents directly using magnetic resonance imaging that can cause the phase of the spins to change. Our goal in this paper is to use the calculated magnetic field of a dendrite to estimate the resulting phase shift in the magnetic resonance signal. The field produced by a dense collection of simultaneously active dendrites may be just detectable under the most ideal circumstances, but in almost every realistic case the field cannot be detected using current MRI technology. 相似文献
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Linda WM van Kerkhof Ruth Damsteegt Viviana Trezza Pieter Voorn Louk JMJ Vanderschuren 《Neuropsychopharmacology》2013,38(10):1899-1909
Social play behavior is a characteristic, vigorous form of social interaction in young mammals. It is highly rewarding and thought to be of major importance for social and cognitive development. The neural substrates of social play are incompletely understood, but there is evidence to support a role for the prefrontal cortex (PFC) and striatum in this behavior. Using pharmacological inactivation methods, ie, infusions of GABA receptor agonists (baclofen and muscimol; B&M) or the AMPA/kainate receptor antagonist 6,7-dinitroquinoxaline-2,3(1H,4H)-dione (DNQX), we investigated the involvement of several subregions of the medial PFC and striatum in social play. Inactivation of the prelimbic cortex, infralimbic cortex, and medial/ventral orbitofrontal cortex using B&M markedly reduced frequency and duration of social play behavior. Local administration of DNQX into the dorsomedial striatum increased the frequency and duration of social play, whereas infusion of B&M tended to have the same effect. Inactivation of the nucleus accumbens (NAcc) core using B&M increased duration but not frequency of social play, whereas B&M infusion into the NAcc shell did not influence social play behavior. Thus, functional integrity of the medial PFC is important for the expression of social play behavior. Glutamatergic inputs into the dorsomedial striatum exert an inhibitory influence on social play, and functional activity in the NAcc core acts to limit the length of playful interactions. These results highlight the importance of prefrontal and striatal circuits implicated in cognitive control, decision making, behavioral inhibition, and reward-associated processes in social play behavior. 相似文献
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Thomas Cordner Thorlene Egerton Katharine Schubert Tanya Wijesinghe Gavin Williams 《Archives of physical medicine and rehabilitation》2021,102(4):735-751
ObjectivesTo determine whether ballistic resistance training is feasible, safe, and effective in improving muscle strength, power generation, and mobility in adults with neurologic conditions.Data SourcesNine electronic databases were searched from inception to March 2019 in addition to the reference lists of included articles.Study SelectionArticles were independently screened by 2 authors and were included if they were full-text; English-language articles published in a peer-reviewed journal; investigated ballistic resistance training for adults with a neurologic condition; and reported on feasibility, safety, strength, power, or mobility.Data ExtractionTwo authors independently extracted data. Study quality was assessed using the McMaster critical review form and the Physiotherapy Evidence Database scale.Data SynthesisThe search identified 1540 articles, with 13 articles describing 9 studies meeting the criteria for inclusion. Five studies were randomized controlled trials and 4 were cohort studies. Ballistic resistance training was feasible and safe with only 1 intervention-related adverse event reported. Findings indicated improvements in strength for hip abduction, leg press, knee flexion, and ankle dorsiflexion, but not for hip flexion, hip extension, knee extension, or ankle plantarflexion. Muscle power generation improved for hip flexion, hip abduction, leg press, knee extension, and knee flexion, but not for ankle plantarflexion. Treatment effect was positive for self-selected walking speed, with a standardized mean difference (SMD) of 0.69 (95% confidence interval [CI], 0.01-1.38) from 3 studies. However, fastest comfortable walking speed results were inconclusive with a SMD from 4 studies of 0.45 (95% CI, –0.01 to 0.91).ConclusionsBallistic training is safe and feasible for people with a neurologic condition. The effects on muscle strength, power generation, and mobility were found to be positive but not conclusive. 相似文献
108.
目的:探讨中药保元强肾Ⅱ号胶囊对慢性肾功能衰竭(CRF)的疗效及机理。方法:60例CRF患者随机分为保元强肾Ⅱ号胶囊加洛汀新组(治疗组,30例)及必需氨基酸加洛汀新组(对照组,30例),观察肾功能及肾小管标志蛋白的改变。结果:治疗组显效率及总有效率分别为633%及933%;对照组分别为300%及567%,治疗组疗效明显优于对照组(P<001);治疗组治疗后BUN、SCr及CCr均较治前明显改善,尿视黄醇结合蛋白、尿β2微球蛋白及尿N乙酰氨基葡萄糖苷酶均比治疗前显著降低,TammHorfau蛋白比治疗前显著增高(P<001或P<005)。结论:保元强肾Ⅱ号胶囊对肾小管间质损伤有明显的改善作用,从而改善肾功能,提高疗效。 相似文献
109.
We present an analysis of the relative information content of cortical current source reconstructions from electroencephalogram (EEG) and magnetoencephalogram (MEG) forward calculations by examining the spatial filters that relate the internal sources with the externally measured electric potentials and magnetic fields. The forward spatial filters are seen to be low-pass functions of spatial frequency and spatial resolution degrades in external measurements. Inverse spatial filters may be used to reconstruct cortical sources from external data, but since they are high-pass functions of spatial frequency, they must be regularized to avoid instabilities caused by noise at higher spatial frequencies. The regularization process limits the spatial resolution of source reconstructions. EEG forward spatial filters fall off at lower spatial frequencies than MEG filters; hence, there is less information available in higher spatial frequencies resulting in lower spatial resolution in inverse reconstructions. The tangential component of the magnetic field provides even higher spatial resolution than can be obtained using the radial component. An accompanying article examines the surface Laplacian for both the EEG and the MEG. © 2001 Biomedical Engineering Society.
PAC01: 8710+e, 0230Zz, 8719Nn 相似文献
110.