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31.
Xi Yu Jennifer Zuk Meaghan V. Perdue Ola Ozernov‐Palchik Talia Raney Sara D. Beach Elizabeth S. Norton Yangming Ou John D. E. Gabrieli Nadine Gaab 《Human brain mapping》2020,41(10):2827-2845
Developmental dyslexia affects 40–60% of children with a familial risk (FHD+) compared to a general prevalence of 5–10%. Despite the increased risk, about half of FHD+ children develop typical reading abilities (FHD+Typical). Yet the underlying neural characteristics of favorable reading outcomes in at‐risk children remain unknown. Utilizing a retrospective, longitudinal approach, this study examined whether putative protective neural mechanisms can be observed in FHD+Typical at the prereading stage. Functional and structural brain characteristics were examined in 47 FHD+ prereaders who subsequently developed typical (n = 35) or impaired (n = 12) reading abilities and 34 controls (FHD?Typical). Searchlight‐based multivariate pattern analyses identified distinct activation patterns during phonological processing between FHD+Typical and FHD?Typical in right inferior frontal gyrus (RIFG) and left temporo‐parietal cortex (LTPC) regions. Follow‐up analyses on group‐specific classification patterns demonstrated LTPC hypoactivation in FHD+Typical compared to FHD?Typical, suggesting this neural characteristic as an FHD+ phenotype. In contrast, RIFG showed hyperactivation in FHD+Typical than FHD?Typical, and its activation pattern was positively correlated with subsequent reading abilities in FHD+ but not controls (FHD?Typical). RIFG hyperactivation in FHD+Typical was further associated with increased interhemispheric functional and structural connectivity. These results suggest that some protective neural mechanisms are already established in FHD+Typical prereaders supporting their typical reading development. 相似文献
32.
功能性便秘的发生严重困扰着现代人群,进而影响人们的生活质量。杜长海名老中医认为功能性便秘究其内因为大肠传导失常,外因乃现代人的生活方式、紧张的生活氛围等等,因此杜老结合自己数十年的临床经验,根据中医辨证总结出临床常用药对,对有效治疗功能性便秘进行了经验总结。 相似文献
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目的研究布拉酵母联合小剂量红霉素对功能性消化不良患儿血清胃动素、胃泌素的影响。方法以某医院2017年8月—2018年10月收治的90例功能性消化不良患儿为研究对象,采用随机数字法将所有患儿分为对照组(n=45)、观察组(n=45)。对照组应用小剂量红霉素对患儿进行治疗,观察组在小剂量红霉素的基础上联合布拉酵母治疗。结果观察组恶心、呕吐、嗳气、腹胀及疼痛评分[(7.68±1.78)分、(6.42±0.92)分、(8.21±1.25)分、(8.34±1.33)分、(7.24±1.63)分]均低于对照组[(10.34±1.09)分、(9.42±1.18)分、(12.71±1.43)分、(13.70±1.36)分、(15.39±1.56)分],差异有统计学意义(P<0.05);观察组治疗后血清胃动素为(281.16±45.81)ng/L、胃泌素为(182.65±16.81)ng/L,高于对照组,总有效率(97.78%)高于对照组,差异均有统计学意义(P<0.05)。结论布拉酵母联合小剂量红霉素对功能性消化不良患儿治愈率显著,与其提高患儿胃动素、胃泌素的水平相关。 相似文献
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The inferior alveolar nerve and facial nerve are the two most important nerves in the dental and maxillofacial region. The injury to them is one of the major postoperative complications after alveolar surgery and orthognathic surgery. However, recovering the nerve function after injury takes a long time and the recovery effect tends to be unsatisfactory. In recent years, an intensively investigated technique, low level laser which has been applying in assisting the recovery of nerve function, has been gradually proved to be effective in clinically treating postoperative nerve injury. In this article we review in terms of the mechanisms involved in low level laser-assisted functional restoration of nerve injury and its clinical application in the recovery of nerve function in the dental and maxillofacial area as well. 相似文献
37.
《Annals of physical and rehabilitation medicine》2020,63(5):416-421
ObjectiveTo evaluate the relationship between neural (re)organization of the somatosensory cortex and impairment of sensory function (2-point discrimination [2PD]) in individuals with unilateral cerebral palsy.MethodsWe included 21 individuals with unilateral cerebral palsy. 2PD thresholds were evaluated on thumb pads, and activation of the somatosensory cortex was recorded by functional MRI (fMRI) during passive movements of the affected hand. A lateralization index (LI) was calculated for the primary sensory (S1) and secondary sensory (S2) cortices and the correlation between the LI and 2PD thresholds was analysed.ResultsWe found a significant negative correlation between the 2PD thresholds and the S2 LI (r = −0.5, one-tailed P-value = 0.01) and a trend towards a negative correlation with the S1 LI (r = −0.4, one-tailed P-value = 0.05).ConclusionHigh levels of activation in the contralesional hemisphere were associated with high levels of sensory impairment in individuals with unilateral cerebral palsy. The interhemispheric (re)organization of the somatosensory system may not effectively compensate for somatosensory impairment. 相似文献
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《Journal of Medical Imaging and Radiation Sciences》2015,46(4):420-426
PurposeAttempts by magnetic resonance (MR) manufacturers to help imaging centres improve patient throughput has led to the development of more automated acquisition. This software is capable of customizing individual scan alignment; potentially improving imaging efficiency and standardizing protocols. However, substantial investments are required to introduce such systems, potentially deterring their widespread application. This study assessed the implementation costs and reduction in examination durations for automated knee MR imaging (MRI) software.Materials and MethodsResearch activities were performed at a community-based academic centre on a 3-Tesla (3-T) system using Siemens' Day Optimizing Throughput (Dot) knee software. Examination acquisition times were extracted from the system before and after software implementation. Fiscal year 2012/13 finances were used to determine the average hourly cost of MRI utilization. Costs associated with automated software implementation were also calculated. Finally, the number of knee scans required to achieve a positive return on investment using the software was established.Results and DiscussionThe mean (standard deviation, sample size) pre- and post-Dot software scan times were 23.20 (4.18, n = 266) and 21.94 (4.51, n = 59) minutes, respectively, for a routine knee scan and 11.88 (1.60, n = 74) and 11.24 (1.51, n = 27) minutes, respectively, for a fast knee scan. The overall weighted average resulted in a 64-second time savings per automated knee examination. This negligible time savings would be extremely difficult to make use of clinically. Dot simplified 29 unique knee protocols to two, improving the consistency of knee examinations. Current Dot software is not compatible with all patients and therefore has limitations that are a concern among MR technologists.ConclusionAdoption of automated knee systems could assist in standardizing protocols; however, the cost of implementation and difficulty in modifying patient scheduling to reflect the minimal time savings would make a financial return unlikely to occur at small- and medium-sized institutions. 相似文献