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31.
Abstract

Objective: We examined cortical auditory development and behavioral outcomes in children with ANSD fitted with cochlear implants (CI). Design: Cortical maturation, measured by P1 cortical auditory evoked potential (CAEP) latency, was regressed against scores on the infant toddler meaningful auditory integration scale (IT-MAIS). Implantation age was also considered in relation to CAEP findings. Study sample: Cross-sectional and longitudinal samples of 24 and 11 children, respectively, with ANSD fitted with CIs. Results: P1 CAEP responses were present in all children after implantation, though previous findings suggest that only 50–75% of ANSD children with hearing aids show CAEP responses. P1 CAEP latency was significantly correlated with participants’ IT-MAIS scores. Furthermore, more children implanted before age two years showed normal P1 latencies, while those implanted later mainly showed delayed latencies. Longitudinal analysis revealed that most children showed normal or improved cortical maturation after implantation. Conclusion: Cochlear implantation resulted in measureable cortical auditory development for all children with ANSD. Children fitted with CIs under age two years were more likely to show age-appropriate CAEP responses within six months after implantation, suggesting a possible sensitive period for cortical auditory development in ANSD. That CAEP responses were correlated with behavioral outcome highlights their clinical decision-making utility.  相似文献   
32.
The 3×Tg‐AD mouse is one of the most studied animal models of Alzheimer's disease (AD), and develops both amyloid beta deposits and neurofibrillary tangles in a temporal and spatial pattern that is similar to human AD pathology. Additionally, abnormal myelination patterns with changes in oligodendrocyte and myelin marker expression are reported to be an early pathological feature in this model. Only few diffusion MRI (dMRI) studies have investigated white matter abnormalities in 3×Tg‐AD mice, with inconsistent results. Thus, the goal of this study was to investigate the sensitivity of dMRI to capture brain microstructural alterations in 2‐month‐old 3×Tg‐AD mice. In the fimbria, the fractional anisotropy (FA), kurtosis fractional anisotropy (KFA), and radial kurtosis (K) were found to be significantly lower in 3×Tg‐AD mice than in controls, while the mean diffusivity (MD) and radial diffusivity (D) were found to be elevated. In the fornix, K was lower for 3×Tg‐AD mice; in the dorsal hippocampus MD and D were elevated, as were FA, MD, and D in the ventral hippocampus. These results indicate, for the first time, dMRI changes associated with myelin abnormalities in young 3×Tg‐AD mice, before they develop AD pathology. Morphological quantification of myelin basic protein immunoreactivity in the fimbria was significantly lower in the 3×Tg‐AD mice compared with the age‐matched controls. Our results demonstrate that dMRI is able to detect widespread, significant early brain morphological abnormalities in 2‐month‐old 3×Tg‐AD mice.  相似文献   
33.
34.
Background: Atopic dermatitis (AD) is a chronic, relapsing skin disorder which is strictly determined by the epidermal barrier function. In previous studies, there is conclusive evidence that normal‐looking, nonlesional skin presents meaningful barrier function defect and a sub‐clinical eczematous skin reaction. Aim: The authors intended to visualize nonlesional AD skin with the use of high frequency ultrasonography to show that the normal‐looking, nonlesional skin may present significant abnormalities in USG examination. Methods: We have performed analysis with the use of high‐frequency 20 MHz skin sonography in the cases of 15 AD patients of the Department of Dermatology, Medical University, Poznań, Poland. The clinical score has been evaluated on the basis of W‐AZS index and EASI. The results were presented in the form of ultrasonographic images. Results: High frequency ultrasonography revealed an echopoor band within nonlesional skin of six (40%) examined AD patients and in all cases within skin lesions. Conclusion: Our results indicate the significant role of skin ultrasonography in the complete clinical evaluation of patients with AD, which may serve as an element in selection of the most appropriate topical treatment. An echopoor band beneath the echo entry within nonlesional skin of some AD patients may reflect subclinical eczematous reaction and the readiness for the development of typical skin lesions. For this purpose, we suggest to name an intact skin in AD as seemingly healthy skin.  相似文献   
35.

Background

Atopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malassezia globosa was identified as the major histamine releasing antigen in human sweat.

Methods

The full length cDNA of the counterpart of MGL_1304 in Malassezia restricta (Mala r 8), was cloned by degenerate PCR and rapid identification of cDNA ends (RACE). Recombinant MGL_1304, and its counterparts, Mala s 8 (produced by Malassezia sympodialis) and Mala r 8 were prepared, and compared in their allergenicities by dot blot analysis and histamine release tests with sera and basophils of patients with AD.

Results

The identities between MGL_1304 and Mala s 8, MGL_1304 and Mala r 8, and Mala s 8 and Mala r 8 were 68%, 78%, and 76%, respectively, in protein sequences. Dot blot analysis revealed that the level of IgE binding to Mala s 8 was higher than that of MGL_1304. However, histamine release tests revealed that MGL_1304 and Mala r 8 possessed higher activity than Mala s 8. In addition, the crude lysate of M. globosa showed higher histamine release ability than that of M. sympodialis.

Conclusions

Patients with AD showed hypersensitivities against MGL_1304 and its homologs. However, the allergenicities of the homologs are variable and the histamine release activities may be different from the solid-phase binding activities for IgE. Sweat allergy should be carefully evaluated with biological activities of MGL_1304 and its homologs of other Malassezia fungi residing on the skin.  相似文献   
36.
电针对老年性痴呆模型大鼠海马线粒体酶活性的影响   总被引:14,自引:1,他引:14  
目的研究电针对老年性痴呆(AD)模型大鼠海码神经元线粒体酶活性的影响,从能量代谢的角度探讨电针治疗AD的部分作用机制。方法以D-半乳糖腹腔注射和Aβ1-40海马注射诱导形成的AD模型大鼠为研究对象,电针“百会”、“涌泉”穴,每日1次,连续20d。以通道式水迷宫测试学习记忆能力的变化,评价电针对AD的治疗效庸;以生化方法检测海马神经元线粒体琥珀酸脱氢酶、Na^+ -K^+ -ATP酶、Ca^2+ -Mg^2+ -ATP酶的活性。结果电针能有效改善AD模型大鼠学习记忆能力,提高线粒体琥珀酸脱氢酶、Na^+ -K^+ -ATP酶、Ca^2+ -Mg^2+ -ATP酶活性。结论电针可促进ATP的合成与分解利用,调节线粒体功能,改善AD能量代谢障碍。  相似文献   
37.
目的研究绞股蓝正丁醇部位对阿尔茨海默病(AD)模型小鼠学习记忆的影响。方法采用Morris水迷宫方法对小鼠记忆行为进行检测;采用ELISA法测定SOD、GSH-PX和MDA的含量;采用HE法染色观察对小鼠大脑海马组织的影响。结果绞股蓝正丁醇部位能改善老年痴呆小鼠的学习记忆能力;能促进SOD和GSH-PX生成,抑制MDA的生成。结论绞股蓝正丁醇部位可提高AD小鼠的抗氧化能力,从而起到防治AD的作用。  相似文献   
38.

Objective

To characterize the end-of-life care of all international patients who died at a global destination medical center from January 1, 2005, through December 31, 2015.

Patients and Methods

We performed a retrospective review of all adult international patients who died at a global destination medical center from January 1, 2005, through December 31, 2015.

Results

Eighty-two international patients from 25 countries and 5 continents died during the study period (median age, 59.5 years; 59% male). Of the study cohort, 11% (n=9) completed an advance directive, 61% (n=50) died in the intensive care unit, 26% (n=21) had a full code order at the time of death, and 73% (n=19 of 26) receiving cardiopulmonary resuscitation did not survive the resuscitation process.

Conclusion

Seriously ill international patients who travel to receive health care in the United States face many barriers to receiving high-quality end-of-life care. Seriously ill international patients are coming to the United States in increasing numbers, and little is known about their end-of-life care. There are many unique needs in the care of this complex patient population, and further research is needed to understand how to provide high-quality end-of-life care to these patients.  相似文献   
39.
目的从重组柞蚕抗菌肽AD毕赤酵母发酵液中分离纯化出抗菌肽纯品,并对其进行纯度、分子量和抗菌作用的鉴定。方法用离子交换和疏水层析法对发酵液中的重组柞蚕抗菌肽AD进行分离纯化,用高效液相色谱法分析产物的纯度,再用基质辅助激光解析—飞行时间质谱仪对产物进行分子量鉴定,并结合传统微量肉汤稀释法和流式细胞术分析重组柞蚕抗菌肽AD纯品对E.coli敏感株及耐药株的抗菌作用。结果重组柞蚕抗菌肽AD经离子交换和疏水层析纯化后的纯度达到98.40%,分子量为4068.15Da,与所设计的重组柞蚕抗菌肽AD大小相近。所纯化出的重组柞蚕抗菌肽AD对E.coli的敏感株ATCC25922和产β-内酰胺酶耐药株株ATCC35218的抗菌作用均为MIC 8μg/m L,而头孢他啶和氨苄西林对耐药株ATCC35218的MIC的值分别为8μg/m L和>32μg/m L。结论成功纯化分离出具有自主知识产权的重组柞蚕抗菌肽AD,其对E.coli敏感株和耐药株具有相同的抗菌效果。  相似文献   
40.

Objectives

To compare the effects of conventional core stabilization and dynamic neuromuscular stabilization (DNS) on anticipatory postural adjustment (APA) time, balance performance, and fear of falls in chronic hemiparetic stroke.

Design

Two-group randomized controlled trial with pretest-posttest design.

Setting

Hospital rehabilitation center.

Participants

Adults with chronic hemiparetic stroke (N=28).

Interventions

Participants were randomly divided into either conventional core stabilization (n=14) or DNS (n=14) groups. Both groups received a total of 20 sessions of conventional core stabilization or DNS training for 30 minutes per session 5 times a week during the 4-week period.

Main Outcome Measures

Electromyography was used to measure the APA time for bilateral external oblique (EO), transverse abdominis (TrA)/internal oblique (IO), and erector spinae (ES) activation during rapid shoulder flexion. Trunk Impairment Scale (TIS), Berg Balance Scale (BBS), and Falls Efficacy Scale (FES) were used to measure trunk movement control, balance performance, and fear of falling.

Results

Baseline APA times were delayed and fear of falling was moderately high in both the conventional core stabilization and DNS groups. After the interventions, the APA times for EO, TrA/IO, and ES were shorter in the DNS group than in the conventional core stabilization group (P<.008). The BBS and TIS scores (P<.008) and the FES score (P<.003) were improved compared with baseline in both groups, but FES remained stable through the 2-year follow-up period only in the DNS group (P<.003).

Conclusions

This is the first clinical evidence highlighting the importance of core stabilization exercises for improving APA control, balance, and fear of falls in individuals with hemiparetic stroke.  相似文献   
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