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81.
新生儿疾病筛查时血片采集过程中存在的问题   总被引:1,自引:0,他引:1  
新生儿疾病筛查是落实《母婴保健法》,提高出生人口素质的重要措施.东营市自2000年开展此项工作,利津县计生妇幼站担负着本县辖区内各接生单位所采集的新生儿疾病筛查血片的定期收集、质量初筛及报送工作.  相似文献   
82.
Although combined spin‐ and gradient‐echo (SAGE) dynamic susceptibility‐contrast (DSC) MRI can provide perfusion quantification that is sensitive to both macrovessels and microvessels while correcting for T1‐shortening effects, spatial coverage is often limited in order to maintain a high temporal resolution for DSC quantification. In this work, we combined a SAGE echo‐planar imaging (EPI) sequence with simultaneous multi‐slice (SMS) excitation and blipped controlled aliasing in parallel imaging (blipped CAIPI) at 3 T to achieve both high temporal resolution and whole brain coverage. Two protocols using this sequence with multi‐band (MB) acceleration factors of 2 and 3 were evaluated in 20 patients with treated gliomas to determine the optimal scan parameters for clinical use. ΔR2*(t) and ΔR2(t) curves were derived to calculate dynamic signal‐to‐noise ratio (dSNR), ΔR2*‐ and ΔR2‐based relative cerebral blood volume (rCBV), and mean vessel diameter (mVD) for each voxel. The resulting SAGE DSC images acquired using MB acceleration of 3 versus 2 appeared visually similar in terms of image distortion and contrast. The difference in the mean dSNR from normal‐appearing white matter (NAWM) and that in the mean dSNR between NAWM and normal‐appearing gray matter were not statistically significant between the two protocols. ΔR2*‐ and ΔR2‐rCBV maps and mVD maps provided unique contrast and spatial heterogeneity within tumors.  相似文献   
83.
IntroductionGlobal hippocampal atrophy has been repeatedly reported in patients with Parkinson's disease (PD). However, there is limited literature on the differential involvement of hippocampal subfields among PD motor subtypes. This study aimed to investigate hippocampal subfield alterations in patients with PD based on their predominant symptoms.MethodWe enrolled 31 PD patients with the tremor-dominant (TD) subtype, 27 PD patients with postural instability and gait disturbance-dominant (PIGD) subtype, and 40 healthy controls (HCs). All participants underwent high-spatial-resolution T1-weighted magnetic resonance imaging. The volume of hippocampal subfields was measured using FreeSurfer software, compared across groups, and correlated with clinical features.ResultsWe found volumetric reductions in the hippocampal subfield in both patient subtypes compared to HCs, which were more pronounced in the PIGD subtype. The PIGD subtype had accelerated age-related alterations in the hippocampus compared to the TD subtype. Bilateral hippocampal volumes were positively associated with cognitive performance levels, but not with disease severity and duration in patients.ConclusionsAlterations in the hippocampal subfields of patients with PD differed based on their predominant symptoms. These findings are of relevance for understanding the pathophysiology of the increased risk of cognitive impairment in PIGD.  相似文献   
84.
The hippocampus has been suggested to show protracted postnatal developmental growth across childhood. Most previous studies during this developmental period have been cross-sectional in nature and have focused on age-related differences in either hippocampal subregions or subfields, but not both, potentially missing localized changes. This study capitalized on a latent structural equation modeling approach to examine the longitudinal development of hippocampal subfields (cornu ammonis (CA) 2-4/dentate gyrus (DG), CA1, subiculum) in both the head and the body of the hippocampus, separately, in 165 typically developing 4- to 8-year-old children. Our findings document differential development of subfields within hippocampal head and body. Specifically, within hippocampal head, CA1 volume increased between 4−5 years and within hippocampal body, CA2-4/DG and subiculum volume increased between 5−6 years. Additionally, changes in CA1 volume in the head and changes in subiculum in the body between 4−5 years related to improvements in memory between 4−5 years. These findings demonstrate the protracted development of subfields in vivo during early- to mid-childhood, illustrate the importance of considering subfields separately in the head and body of the hippocampus, document co-occurring development of brain and behavior, and highlight the strength of longitudinal data and latent modeling when examining brain development.  相似文献   
85.
目的:建立一种适用于膜片钳记录研究的成年大鼠延髓薄片制备方法。方法:用改制的注射器将延髓和上颈髓段从离断的椎管中直接吹出;采用水平切的方式制备延髓薄片;记录三叉神经脊束核尾侧亚核(Vc)神经元的自发放电和诱发放电活动。结果:分离得到的延髓和上颈髓标本光滑完整;水平切的延髓薄片较好地保持了Vc的形态学结构和神经元活性,可较好地记录到Vc神经元自发的兴奋性突触后电流和诱发的双脉冲抑制活动。结论:本方法操作简单,取材快速,延髓薄片外形完整且能保持神经元活性,适用于成年大鼠Vc的膜片钳研究。  相似文献   
86.
目的:探究分析在脊柱外伤诊断中运用16排螺旋CT扫描技术的诊断效果。方法:选取我院2018年8月-2019年8月期间收治的50例脊柱外伤患者为本次研究资料来源,对所有患者安排进行16排螺旋CT扫描检查,通过多平面重建和表面遮盖等方式成像,对所有患者的伤情进行观察记录。结果:经过扫查,发现在50例患者中,单纯屈曲压缩型外伤的患者有28例(56%),爆裂性外伤的患者有9例(18%),骨折脱位伤的患者有11例(22%);其中,有2例患者漏诊误诊,诊断准确率为48例(96%),漏诊误诊率为2例(4%)。结论:在脊柱外伤患者诊断中运用16排螺旋CT扫描技术进行诊断扫查,有助于快速查清患者受伤原因,能够取得较高的诊断准确率,漏诊误诊率较低,对制定科学有效的治疗方案具有重要意义,是一种具有较高应用价值的值得大力推广应用于临床的伤情诊断方式。  相似文献   
87.
目的研究分析64层螺旋CT联合心肌酶检查应用于急性心源性胸痛诊断的临床价值。方法随机选取2008年2月~2011年3月我院收治的45例急性心源性胸痛患者作为治疗组,抽取同期来我院体检中心进行检查的45例健康者作为对照组,对照组单纯给予MSCTA(64层螺旋CT血管成像)进行检查。治疗组在此基础上联合血清心肌酶检查,观察两组患者的诊断情况。结果治疗组患者经MSCTA联合心肌酶检查诊断急性心源性胸痛特异性为100%,敏感性为95.56%,显著高于对照组93.33%、86.67%,组间差异显著,具有统计学意义(P0.05);经MSCTA分辨钙化粥样斑块CT值为(341.65±308.42)HU,非钙化粥样斑块CT值为(59.88±67.93)HU,差异显著,具有统计学意义(P0.05)。结论 64层螺旋CT联合心肌酶检查应用于诊断急性心源性胸痛效果良好,准确率较高,同时对判断冠状动脉斑块与狭窄性质具有积极的意义。  相似文献   
88.
89.
目的探讨氢气对乳鼠海马神经元细胞缺氧/复氧损伤后细胞活力的影响。方法原代培养的SD乳鼠海马神经元细胞,随机分成对照组,缺氧/复氧组和氢气预处理组。对照组常规培养;缺氧/复氧组在100%N2中培养15min后复氧30min;氢气预处理组在2%H2+98%N2中培养15min后复氧30min。采用MTT法检测乳鼠海马神经元细胞活力。结果氢气预处理能够增强细胞活力(P<0.05)。结论氢气预处理对海马神经元细胞缺氧/复氧损伤具有保护作用,可能与提高细胞活力有关。  相似文献   
90.
Abstract

School, Okayama, Japan The etiology of amyotrophic lateral sclerosis (ALS) remains unknown although an existence of neurotoxic substances in cerebrospinal fluid (CSF) from ALS patients have been postulated. In order to investigate a possible effect of CSF from ALS patients on cellular signaling in spinal neurons, we compared Fos-like immunoreactivity (Fos-LI) in organotypic cultures of rat lumbar spinal cord after addition of CSF from ALS patients or another neurologic disease. Fos-LI was normally present predominantly in dorsal horn neurons, whereas only a few ventral horn neurons were positive for Fos-LI. The number of Fos-LI positive neurons significantly increased in dorsal horn with addition of CSF from ALS patients as well as glutamate at 100 μM. However, the increase was not observed with addition of CSF from other neurologic diseases. The increase in Fos-LI positive neurons in dorsal horn was reversed by a further supplement of MK801, an N-methyl-D-aspartate (NMDA) receptor antagonist, but not of CNQX, an a-amino-3-hydroxy-5-methyl-4- isoxazole propionic acid (AMPA)/kainate antagonist. These results indicate that there may be substances in CSF from ALS patients that stimulate Fos expression in certain populations of spinal neurons via the NMDA receptors. [Neurol Res 1999; 21: 309-312]  相似文献   
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