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目的 探讨尿阿尔茨海默病(AD)相关神经丝蛋白(AD7c-NTP)含量测定联合血浆同型半胱氨酸(Hcy)在AD诊断中的价值。方法 纳入轻度阿尔茨海默病(CDR=1分)及中重度阿尔茨海默病患(CDR ≥ 2分)者各40例,并选择健康体检志愿者40例为对照组,采用酶联免疫吸附测定法(ELISA)检测尿液中AD7c-NTP含量,采用循环酶法测定血浆Hcy的含量,通过绘制ROC曲线,分析二者联合检测对AD的诊断准确性。结果 3组受试者尿AD7c-NTP含量比较,差异有统计学意义(P<0.05);组间比较差异均有统计学意义(P<0.05)。根据ROC曲线,当尿AD7c-NTP为1.745 ng/mL时,对应的灵敏度和特异度之和最大。3组受试者血浆Hcy的含量比较,差异有统计学意义(P<0.05);组间比较差异均有统计学意义(P<0.01)。根据ROC曲线,当血浆HCY为15.05 μmol/L时,对应的灵敏度和特异度之和最大。当二者进行联合检测时,ROC曲线下面积为0.891,大于各项单独检测。结论 AD患者尿AD7c-NTP含量及血浆HCY含量均增高;尿液AD7c-NTP含量及血浆HCY含量可作为辅助AD诊断的生物标记物;二者联合检测可提高AD诊断的准确性。 相似文献
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Biodegradable Polydioxanone Microspheres for Transcatheter Arterial Embolization: Proof of Principle
《Journal of vascular and interventional radiology : JVIR》2020,31(12):2132-2140.e5
PurposeTo evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization.Materials and MethodsUnilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100–150 μm and 90–315 μm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility.ResultsEmbolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100–150 μm MS were injected easily through 3-F catheters; the 90–315 μm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild.ConclusionsBiodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent. 相似文献
4.
Diana Santiago Sánchez-Mateos Margarita Jo-Velasco Victoria Alegría-Landa María del Carmen Fariña-Sabaris Luis Requena 《Journal of cutaneous pathology》2020,47(3):269-274
Lichen sclerosus involving the hands is very uncommon. On the other hand, degenerative collagenous plaques of the hands is a rare condition characterized by keratotic, translucent papules in linear array, on the radial border of the hands. Histopathologically, lesions of degenerative collagenous plaques of the hands show increased collagen bundles in upper half of the dermis and dermal elastosis. We describe the clinical and histopathological progression experienced by a woman who initially presented lesions with clinical and histopathological appearance of degenerative collagenous plaques of the hands, which evolved into characteristic lichen sclerosus. We propose that some cases of the so-called degenerative collagenous plaques of the hands may represent an acrolocalized lichen sclerosus at an early stage. 相似文献
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Effective Two-Level Domain Decomposition Preconditioners for Elastic Crack Problems Modeled by Extended Finite Element Method 下载免费PDF全文
Xingding Chen & Xiao-Chuan Cai 《Communications In Computational Physics》2020,28(4):1561-1584
In this paper, we propose some effective one- and two-level domain decomposition preconditioners for elastic crack problems modeled by extended finite element method. To construct the preconditioners, the physical domain is decomposed
into the "crack tip" subdomain, which contains all the degrees of freedom (dofs) of the
branch enrichment functions, and the "regular" subdomains, which contain the standard dofs and the dofs of the Heaviside enrichment function. In the one-level additive
Schwarz and restricted additive Schwarz preconditioners, the "crack tip" subproblem
is solved directly and the "regular" subproblems are solved by some inexact solvers,
such as ILU. In the two-level domain decomposition preconditioners, traditional interpolations between the coarse and the fine meshes destroy the good convergence property. Therefore, we propose an unconventional approach in which the coarse mesh
is exactly the same as the fine mesh along the crack line, and adopt the technique of
a non-matching grid interpolation between the fine and the coarse meshes. Numerical experiments demonstrate the effectiveness of the two-level domain decomposition
preconditioners applied to elastic crack problems. 相似文献
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目的探讨间歇性负压封闭引流(VSD)联合自体皮瓣原位弹性绷带加压包扎对III~Ⅳ期溃疡期压疮疗效的影响。方法选择2009年4月~2014年3月我科住院治疗的溃疡性压疮患者40例作为观察组,采用间歇性VSD联合自体皮瓣原位弹性绷带加压包扎的治疗方法。选择同期我科住院治疗的III~Ⅳ期溃疡性压疮患者25例作为对照组,采用常规换药联合自体皮瓣原位弹性绷带加压包扎的治疗方法。观察两组感染发生率、愈合情况及住院时间,并进行比较。结果观察组感染率为0,对照组感染率为76%,两组比较有显著性差异(P0.05);观察组皮瓣修复术前住院时间、术后住院时间、总住院时间较对照组明显缩短,两组比较有显著性差异差异(P0.05)。两组皮瓣面积、一期愈合、复发情况比较无显著性差异(P0.05)。结论间歇性VSD联合自体皮瓣原位弹性绷带加压包扎,能阻止溃疡期压疮创面感染,促进创面愈合,改善预后。 相似文献
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Multinucleate cell angiohistiocytoma (MCAH) is a vascular and fibrohistiocytic proliferation with unknown pathogenesis. Clinical lesions tend to be localized to an anatomical area. Exceptionally, the generalized variant is rare. This study reports three cases of generalized MCAH, and analyzes the clinicopathological features of 15 cases reviewed in the published work. Compared with the localized variant, generalized MCAH affected both sexes equally, had an earlier age of onset and a predilection for the trunk and extremities. Histopathologically, the most characteristic feature is the giant, bizarre multinucleate cells with angulated cytoplasm. Systemic diseases or abnormal immune conditions were revealed in six patients with generalized MCAH. For the first time, we found that the present cases showed increased elastic fibers in the affected areas, suggesting that the synthetic function of fibroblasts was active. This study suggested that MCAH originates from fibroblasts and is a distinct entity with potential correlation with abnormal immune states. 相似文献
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目的 系统评价弹性抗阻运动(弹力带/弹力管)对慢性阻塞性肺疾病(COPD)患者康复疗效的影响。方法 检索Cochrane Library、PubMed、Web of Science、中国知网、维普、万方和生物医学文献数据库中关于弹性抗阻运动治疗COPD患者的临床随机对照试验,检索时限自建库至2020年9月。最后纳入文献11篇,其中英文9篇,中文2篇,共485例患者。采用Cochrane风险偏倚评估工具及物理治疗证据数据库量表进行质量评价,采用RevMan 5.2软件进行分析。这一系统评价在PROSPERO(CRD42020208659)上登记。结果 弹性抗阻运动组与传统抗阻运动组(如举重训练机、体重训练) 6 min步行试验距离(6WMD) (MD = 1.19, 95%CI -7.02~9.39, P = 0.78)、COPD患者自我评估测试(CAT) (MD = -0.43, 95%CI -2.42~1.57, P = 0.68)和肌力(MD = 0.23, 95%CI -1.06~1.52, P = 0.73)无显著性差异,两组间异质性不高。弹性抗阻运动组与非抗阻运动组6MWD (MD = 18.30, 95%CI -8.92~45.52, P = 0.19)和CAT (MD = -0.59, 95%CI -3.78~2.60, P = 0.72)无显著性差异,研究间异质性较高。结论 弹性抗阻运动也许是一种潜在的替代传统抗阻训练的方法,但弹性抗阻运动对运动耐力、生活质量、肺功能的影响尚不明确。 相似文献