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We sought to simultaneously confirm that substantial recovery at day 1 and day 7 after acute ischaemic stroke onset is associated with subsequent neurological deterioration in patients of the Acute Stroke Therapy by Inhibition of Neutrophils randomized clinical trial. Substantial recovery was assessed by improvement in the National Institutes of Health Stroke Score (NIHSS). Neurological deterioration was defined as any stroke event or NIHSS worsening from recovery assessment to day 90. After adjusting for age, t-PA and day 1 NIHSS, there was a non-significant tendency of substantial (pre-specified as 75%) recovery at day 1 to be associated with later deterioration [odds ratio (OR) 2.47; 95% CI, 0.95–6.50]. The corresponding OR for substantial (pre-defined as 65%) recovery at day 7 was 1.84 (0.85–3.96). Other thresholds for recovery were significantly associated with later deterioration: >50%, 80%, 90% and 100% for day 1 and >50%, 60%, 70%, 90% and 100% for day 7. The effect of recovery at day 1 was more important than that of later recovery. This study confirms the association between recovery and subsequent neurological deterioration and is the first to indicate the greater importance of acute recovery at day 1 in comparison with later recovery.  相似文献   
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Abstract: Two autopsied female sibling cases of sudanophilic leukodystrophy are reported. Case A and case B were the second and third of seven siblings, and a sister and a brother died from severe progressive neurological disease with similar symptoms. Consanguineous marriages were noted in the family of both cases through the past three generations. Case A gradually developed intellectual deterioration and tetraplegia at the age of 29, progressed to akinetic mutism within one year and thereafter survived for 14 years. Neuropathologically, a severe atrophy and degeneration were noted in the white matter of the whole cerebrum, sparing the subcortical U-fibers. Myelin and axons were severely damaged with peripheral astrocytic gliosis. Case B developed similar clinical symptoms at the age of 20 and survived for 7 years in the state of akinetic mutism. Similar postmortem findings as those of case A were found in the white matter of the cerebrum with formation of sudanophilic breakdown products and with thick fibrillary gliosis. The pyramidal tract was completely degenerated. There was no accumulation of abnormal lipid in the brains of both cases.  相似文献   
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Vestibular functions are known to show some deterioration with age. Vestibular deterioration is often thought to be compensated for by an increase in neck proprioceptive gain. We studied this presumed compensatory mechanism by measuring psychophysical responses to vestibular (horizontal canal), neck and combined stimuli in 50 healthy human subjects as a function of age (range 15–76 years). After passive horizontal rotations of head and/or trunk (torso) in complete darkness (dominant frequencies 0.05, 0.1, and 0.4 Hz), subjects readjusted a visual target to its remembered prerotational location in space. (1) Vestibular-only stimulus (whole-body rotation); subjects' responses were shifted towards postrotatory body position, this only slightly at 0.4 Hz and pronounced at 0.1 and 0.05 Hz. These errors reflect the known physiological drop of vestibular gain at low rotational frequency. They exhibited a slight but significant increase with age. (2) Neck-only stimulus (trunk rotated, head stationary); the responses showed errors similar to those upon vestibular stimulation (with offset towards postrotatory trunk position) and this again slightly more with increasing age. (3) Vestibular-neck stimulus combination during head rotation on stationary trunk; the errors were close to zero, independent of stimulus frequency and the subjects' age. (4) Opposite stimulus combination (trunk rotated in the same direction as the head, but with double amplitude); the errors were clearly enhanced, essentially reflecting the sum of those with vestibular-only and neck-only stimulation. Taken together, we find a parallel increase in neck- and vestibular-related errors with age, in seeming contrast to previous studies. We explain our and the previous findings by a vestibular-neck interaction model in which two different neck signals are involved. One neck signal is used, in combination with the vestibular signal, for estimating trunk-in-space rotation. It is internally shaped to always match the vestibular signal, so that these two signals cancel each other out when summed during head rotation on stationary trunk. Because of this matching, perceived trunk stationariness during head rotation on the stationary trunk is independent of vestibular deterioration (related to stimulus frequency, age, ototoxic medication, etc.). The other neck proprioceptive signal, coding head-on-trunk rotation, is superimposed on the estimate of trunk-in-space rotation, thereby yielding a notion of head-in-space. This neck signal remains essentially unchanged with vestibular deterioration. Generally, we hold that the transformation of the vestibular signal from the head down to the trunk proceeds further to include the hip and the legs as well as the haptically perceived body support surface; by this, subjects yield a notion of support kinematics in space. As a consequence, spatial orientation is impaired by chronic vestibular deterioration only to the extent that the body support is moving in space, while it is unimpaired (determined by proprioception alone) during body motion with respect to a stationary support. Electronic Publication  相似文献   
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Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool.  相似文献   
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目的 探讨原发性肝癌切除术后门静脉血栓相关性肝坏死的临床表现及诊疗方法。方法 回顾性分析上海东方肝胆外科医院2018年11月至2019年10月8例原发性肝癌切除术后门静脉血栓相关性肝坏死患者的临床资料,包括患者的人口统计学特征、临床表现、手术方式、实验室检查及影像学检查结果、临床诊疗及预后等。结果 原发性肝癌切除术后门静脉血栓相关性肝坏死均发生在术后2周内,无特异性临床症状和体征,实验室检查主要表现为肝功能谷丙转氨酶、乳酸脱氢酶急剧升高,凝血功能指标异常。8例患者中增强CT显示肝脏呈广泛性坏死6例,局限性坏死2例,显示门脉血栓形成5例,肝脏坏死的发生部位与血栓形成的门静脉支血供区域并非完全相关。超声检查5例,均未能显示肝脏组织坏死改变,显示门脉血栓形成4例。8例患者中,7例予以抗凝、改善微循环、护肝等治疗,5例存活,2例死亡;1例患者病情较轻,给予低分子右旋糖酐、改善微循环等治疗后病情缓解。结论 肝功能急剧恶化为原发性肝癌切除术后早期发生门静脉血栓相关性肝坏死主要初发表现,肝脏广泛性坏死或局限性坏死、伴有或不伴有门脉血栓的增强CT表现为其影像学特征。抗凝、改善微循环治疗有一定效果。该病症确切的发病机制、有效的防治方法需要重视和进一步研究。  相似文献   
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介绍了工程抗震理论中一些重要的研究进展,并对若干重要问题进行了探讨,提出了一些新的学术观点。这些问题主要包括抗震设计的目标和优化策略、设防标准的确定、地震作用的计算方法、钢筋混凝土结构地震破坏的机理等。  相似文献   
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