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41.
The rich sensory innervation of the ankle and foot is manifest through the numerous communicating branches linking the neural trunks, particularly the superficial peroneal and sural nerves on the anterolateral aspect of the hindfoot. The 35 communicating branches seen in 55 dissections (58%) were proximal in half of the cases, lying in the malleolar and lateral tarsal regions, and distal in the other half, in the metatarsal region. The communicating branch was straight in 25 cases and curved in 11. The average distances of the communicating branch from the crest of the lateral malleolus and the tubercle of the 5th metatarsal was 4.7 and 4.1 cm, but there was a wide range of values. We believe that stretching of the proximal communicating branch during forced inversion of the ankle and/or foot or during fractures of the calcaneus or direct injury in surgical approaches or arthroscopy of the ankle may lead to unexplained pre- and submalleolar pain. Advances in modern imaging may allow recognition of these branches and guidance of infiltration and even neurolysis in cases of failure of conservative treatment.  相似文献   
42.
Atrial fibrillation (AF) is the most common arrhythmia worldwide associated with significant morbidity and mortality and represents a significant health care burden. Goals of AF treatment include prevention of cardioembolic stroke using anticoagulation and device therapy and restoration of sinus rhythm using antiarrhythmic drugs or catheter ablation techniques. A comprehensive assessment of cardiac chamber size and function is often started with echocardiography as a first line diagnostic imaging strategy. Recently, innovations in advanced imaging using cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) provide a detailed characterization of atrial anatomy and have been shown to accurately exclude thrombus and guide left atrial appendage (LAA) closure or catheter ablation (CA) of atrial fibrillation. Compared to echocardiography, CCT offers an uncompromised spatial resolution and a fast dataset acquisition, with the disadvantages of the need of iodine contrast agent and radiation exposure. CMR, conversely, can rely on very high temporal resolution, the unique feature of tissue characterization and the absence of radiation exposure. However, the main drawbacks of this diagnostic tool are long scan times and low availability. This review will illustrate the vital role of multimodality cardiac imaging in the accurate identification of left atrial, pulmonary vein and LAA size and function, discuss advanced imaging techniques to rule out thrombus and highlight novel CMR and CCT techniques to guide catheter ablation of AF and LAA occlusion.  相似文献   
43.
目的研究平衡易位和倒位携带者对下一代的影响.方法对94例染色体异常者,其中平衡易位70例、倒位携带者24例的妊娠结果进行分析.结果94例染色体异常者,其中70例平衡易位携带者流产或死胎、生育畸形儿、平衡易位携带者及生育正常儿的机会分别为:68.86%、8.33%、11.84%、10.09%;24例倒位携带者流产或死胎、生育畸形儿、倒位携带者及生育正常儿的机会分别为:35.29%、23.53%、21.53%、19.61%.结论平衡易位和倒位携带者,因产生不平衡配子而导致反复流产、死胎、生育畸形儿和染色体异常携带者的风险很大.  相似文献   
44.
BackgroundAlthough chemotherapy-induced leukoencephalopathy has been described in case and cohort studies, literature remains inconclusive about its prevalence and mechanisms. Therefore, we investigated the presence of leukoencephalopathy after multiagent chemotherapy in women treated for breast cancer and potential underlying neuroinflammatory processes.MethodsIn this exploratory study, 15 chemotherapy-treated and 15 age-matched chemotherapy-naïve patients with early-stage breast cancer, as well as 15 healthy controls underwent simultaneous PET-MR neuroimaging, including T1-weighted MPRAGE, T2-weighted FLAIR and dynamic PET with the 18-kDA translocator protein (TSPO) radioligand [18F]DPA-714. Total and regional (juxtacortical, periventricular, deep white matter and infratentorial) lesion burden were compared between the groups with one-way ANOVA. With paired t-tests, [18F]DPA-714 volume of distribution [VT, including partial volume correction (PVC)] in lesioned and normal appearing white matter (NAWM) were compared within subjects, to investigate inflammation. Finally, two general linear models were used to examine the predictive values of neurofilament light-chain (NfL) serum levels on (1) total lesion burden or (2) PVC [18F]DPA-714 VT of lesions showing elevated inflammation.ResultsNo significant differences were found in total or localized lesion burden. However, significantly higher (20–45%) TSPO uptake was observed in juxtacortical lesions (p ≤ 0.008, t ≥ 3.90) compared to NAWM in both cancer groups, but only persisted for chemotherapy-treated patients after PVC (p = 0.005, t = 4.30). NfL serum levels were not associated with total lesion volume or tracer uptake in juxtacortical lesions.ConclusionThis multimodal neuroimaging study suggests that neuroinflammatory processes could be involved in the development of juxtacortical, but not periventricular or deep white matter, leukoencephalopathy shortly after chemotherapy for early-stage breast cancer.  相似文献   
45.
We report a 14 year old male patient ascertained for developmental delay, carrying a de novo pericentric inversion on chr(7)(p14.3q22.3). Sequencing revealed that the breakpoints overlap a LTR sequence on 7q22.3 and a LINE on 7p14.3. A TTTAAA motif was found in proximity of the breakpoints on both arms. In addition the sequencing detected several small micro-rearrangements, deletion, duplication, insertion, at the breakpoints. No significant sequence identity exists between the 7p14.3 and 7q22.3 breakpoints. These features at the breakpoint junctions suggest that the inversion was triggered by the TTTAAA motif, LTR and LINE and healed by a Non Homologous End Joining (NHEJ) mechanism. The genes ATXN7L1 and PDE1C are disrupted by the inversion. PDE1C is responsible for the hydrolysis of the second messenger molecules cAMP and cGMP and is highly expressed in the human heart and certain brain regions. In mice, Pde1c is expressed in migrating neuronal cells within the central nervous system during early embryo development. Although neuronal migration disorder was not seen in our patient, this is the first patient described with haploinsufficiency of PDE1C possibly causing developmental delay.  相似文献   
46.
Watson TL  Clifford CW 《Vision research》2006,46(20):3422-3429
Prolonged exposure to upright and inverted female and male faces produces opposite effects on subsequent judgments of the sex of faces depending on their orientation. We show that the magnitude of this orientation-contingent gender aftereffect can be predicted from simple aftereffects induced separately at the same orientations. The contingent aftereffect can also be induced in faces tilted 90 degrees to the right and left, eliminating any difference in face-processing strategy that may be in operation with upright and inverted faces. This suggests that neurons employing a single face encoding strategy can be activated in an orientation-specific manner.  相似文献   
47.
Visual expertise in fingerprint examiners was addressed in one behavioral and one electrophysiological experiment. In an X-AB matching task with fingerprint fragments, experts demonstrated better overall performance, immunity to longer delays, and evidence of configural processing when fragments were presented in noise. Novices were affected by longer delays and showed no evidence of configural processing. In Experiment 2, upright and inverted faces and fingerprints were shown to experts and novices. The N170 EEG component was reliably delayed over the right parietal/temporal regions when faces were inverted, replicating an effect that in the literature has been interpreted as a signature of configural processing. The inverted fingerprints showed a similar delay of the N170 over the right parietal/temporal region, but only in experts, providing converging evidence for configural processing when experts view fingerprints. Together the results of both experiments point to the role configural processing in the development of visual expertise, possibly supported by idiosyncratic relational information among fingerprint features.  相似文献   
48.
Dynamic magnetic resonance elastography can visualize and measure propagating shear waves in tissue-like materials subjected to harmonic mechanical excitation. This allows the calculation of local values of material parameters such as shear modulus and attenuation. Various inversion algorithms to perform such calculations have been proposed, but they are sensitive to areas of low displacement amplitude (and hence low SNR) that result from interference patterns due to reflection and refraction. A spatio-temporal directional filter applied as a pre-processing step can separate interfering waves so they can be processed separately. Weighted combinations of inversions from such directionally separated data sets can significantly improve reconstructions of shear modulus and attenuation.  相似文献   
49.
The chloroplast genomes in buckwheat species contain large inverted repeats which are at least 4 kbp longer than the majority of those in land plants. The length of the buckwheat inverted repeats was attributable to an additional region located adjacent to the borders of the small single-copy region. We have cloned and sequenced a 5.2-kbp SmaI fragment corresponding to this extra region in the inverted repeats. A homology search revealed that the sequence of the SmaI fragment is highly homologous to one side of the small single-copy region of the inverted repeats in dicot chloroplast DNAs such as tobacco and beechdrops. Interestingly, a 3.7-kbp segment in the middle of the SmaI fragment is inserted in the opposite orientation relative to those of the other dicot species, and 17-bp direct repeats are found located at both the ends of the additional region. These results suggest that expansion of the inverted repeats in buckwheat chloroplast DNA might have been associated with an inversion. Received: 6 May / 1 November 1996  相似文献   
50.
Effects of facial expression on shared attention mechanisms   总被引:3,自引:0,他引:3  
We investigated the effects of facial expression on shared attention mechanisms. A female or male facial stimulus with one of 3 facial expressions (happiness, neutral, or anger) was presented at the center of a display. This facial stimulus gazed toward a subject, or toward the left or right side of the display. After the facial stimulus was offset, a target appeared on the left or right side of the display and the reaction time to the target was measured. In the statistical analysis by ANOVA, there was a significant main effect of congruity between the target position and the gaze direction in both the female and male facial cues, indicating that gaze direction significantly affected reaction time. When the female facial cues were presented, the reaction times for the congruent target position to the gaze direction were significantly shorter in the happy than other facial expressions. However, there were no significant differences in reaction time when the facial stimuli were presented in an inverted orientation. The results demonstrated that facial expression significantly affected shared attention mechanisms.  相似文献   
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