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81.
Motor imagery is defined as the mental execution of a movement without any muscle activity. In the present study, corticospinal excitability was assessed by motor evoked potentials (MEPs) when the subjects imagined isometric elbow flexion at various force levels. Electromyography was recorded from the right brachioradialis, the biceps brachii and the triceps brachii muscles. First, the maximum voluntary contraction (MVC) of elbow flexion was recorded in each subject. Subjects practiced performing 10, 30 and 60 % MVC using visual feedback. After the practice, MEPs were recorded during the imagery of elbow flexion with the forces of 10, 30 and 60 % MVC without any feedback. After the MEPs recording, we assigned subjects to reproduce the actual elbow flexion force at 10, 30 and 60 % MVC. The MEPs amplitudes in the brachioradialis and biceps brachii in the 60 % MVC condition were significantly greater than those in the 10 % MVC condition (p < 0.05). These findings suggest that the enhancement of corticospinal excitability during motor imagery is associated with an increase in imagined force level.  相似文献   
82.
The lungfish, the closest fish to tetrapods, has two types of sensory epithelia in the olfactory organ: the lamellar olfactory epithelium and the recess epithelium. The former resembles the olfactory epithelium of ordinary teleosts and the latter resembles the vomeronasal organ of tetrapods with respect to the G‐protein expressions and the morphological properties of olfactory receptor cells. In contrast to the lamellar olfactory epithelium covering the surface of olfactory lamella, the recess epithelium, together with the glandular epithelium, lines the recesses at the base of olfactory lamellae and is separated from the surrounding tissues by nonsensory epithelium. In the present study, we examined the distribution of these recesses and the relationship between the recess epithelium and the associated gland in the nasal sac of lungfish. We found that the posterior part of the nasal sac contained more recesses than the anterior one, and the medial one contained more recesses than the lateral one. In addition, virtually all recesses consisted of both the recess epithelium and the glandular epithelium. Furthermore, the glandular epithelium was invariably situated proximal to the midline raphe of the nasal sac, and the recess epithelium distal to it. Possible roles of the recess epithelium and the glandular epithelium are discussed.  相似文献   
83.
Although appendiceal anatomical anomalies are very rare, understanding of the anatomical details of these anomalies is important for surgery. In this case report, we present images from multi-detector row computed tomography (MDCT) and histological findings of a rare anatomical appendiceal anomaly originating from the cecum and opening into the terminal ileum like a bridge. These anatomical details were clearly depicted on MDCT with multi-planar reconstruction. MDCT demonstrated a communication between the appendix and terminal ileum. Histological analysis revealed that a normal mucosal layer was maintained from the appendix to the connected ileum, without any evidence of inflammatory or neoplastic changes, and only thickening of the muscular layer of the appendix was identified. Based on these histological findings, the appendix was considered to represent an anatomical anomaly rather than secondary fistula caused by inflammation or neoplasm, which has not yet been reported.  相似文献   
84.
Objective:We investigated the efficacy and exposure to radiation in 320-detector row computed tomography fluoroscopy-guided (CTF-guided) interventions.Methods:We analysed 231 320-detector row CTF-guided interventions (207 patients over 2 years and 6 months) in terms of technical success rates, clinical success rates, complications, scanner settings, overall radiation doses (dose–length product, mGy*cm), patient doses of peri-interventional CT series, and interventional CT (including CTF), as a retrospective cohort study. The relationships between patient radiation dose and interventional factors were assessed using multivariate analysis.Results:Overall technical success rate was 98.7% (228/231). The technical success rates of biopsies, drainages, and aspirations were 98.7% (154/156), 98.5% (66/67), and 100% (8/8), respectively. The clinical success rate of biopsies was 93.5% (146/156). All three major complications occurred in chest biopsies. The median total radiation dose was 522.4 (393.4–819.8) mGy*cm. Of the total radiation dose, 87% was applied during the pre- and post-interventional CT series. Post-interventional CT accounted for 24.4% of the total radiation dose. Only 11.4% of the dose was applied by CTF-guided intervention. Multilinear regression demonstrated that male sex, body mass index, drainage, intervention time, and helical scan as post-interventional CT were significantly associated with higher dose.Conclusion:The 320-detector row CTF interventions achieved a high success rate. Dose reduction in post-interventional CT provides patient dose reduction without decreasing the technical success rates.Advances in knowledge:This is the first study on the relationship between various interventional outcomes and patient exposure to radiation in 320-detector row CTF-guided interventions, suggesting a new perspective on dose reduction.  相似文献   
85.
Clinical Oral Investigations - The aim of this study was to evaluate the combined effects of recombinant human bone morphogenetic protein&nbsp;- 9 (rhBMP-9) loaded onto absorbable collagen...  相似文献   
86.
Odontology - There is no conclusive evidence regarding a causal relationship between periodontitis and atherosclerosis. In this study, we examined the microbiome in the oral cavity and atheromatous...  相似文献   
87.
Journal of Natural Medicines - We evaluated whether the origins of crude drugs derived from arthropods and annelids could be identified using molecular biological techniques. DNA was extracted from...  相似文献   
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The main mechanism of restenosis after directional coronary atherectomy (DCA) remains obscure. We investigated mechanisms of restenosis after DCA in different coronary artery remodeling patterns. DCA was performed in 51 de novo lesions. The lesions were evaluated by intravascular ultrasound (IVUS) before, immediately after, and 6 months after the procedure. According to the IVUS findings before DCA, we classified the lesions into the following 3 groups: (1) positive (n = 10), (2) intermediate (n = 25), and (3) negative (n = 16) remodeling. We measured lumen area, vessel area, and plaque area using IVUS before DCA, immediately after DCA, and at follow-up. Lumen area increase after DCA was mainly due to plaque area reduction in the positive and intermediate remodeling groups (90 plus minus 15% and 80 plus minus 25% increase in lumen area, respectively), whereas that in the negative remodeling group was due to both plaque area reduction (57 plus minus 22% increase in lumen area) and vessel area enlargement (43 plus minus 33% increase in lumen area). The plaque area increase correlated strongly with late lumen area loss in the positive and intermediate remodeling groups (r = 0.884, p <0.001; r = 0.626, p <0.001, respectively), but the decrease in vessel area was not correlated with lumen area loss. In contrast, both an increase in plaque area and a decrease in vessel area were correlated with late lumen area loss (r = 0.632, p = 0.009; r = 0.515, p = 0.041) in the negative remodeling group. Coronary artery restenosis after atherectomy was primarily due to an increase in plaque in the positive and/or intermediate remodeling groups. However, in the negative remodeling group, late lumen loss might have been caused by both an increase in plaque and vessel shrinkage.  相似文献   
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