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21.
C Monteiro B Fernandes J Reis O Tellechea J Freitas A Figueiredo 《Journal of the European Academy of Dermatology and Venereology》2002,16(6):615-617
We report the case of a 75-year-old-woman who presented with bilateral scalp ulcerations and blindness, accompanied by severe headache and scalp tenderness, due to bilateral temporal arteritis without systemic involvement. A biopsy taken from the border of an ulceration showed evidence of giant cell arteritis. She was treated with oral prednisone, 60 mg per day. The ulcerations healed in a few weeks but the vision loss was irreversible. This case highlights for temporal arteritis the importance of accurate and timely diagnosis as well as the need for prompt therapy with systemic steroids in order to avoid major complications, namely loss of vision. It also demonstrates that scalp necrosis and ulcerations are skin signs associated with a poor prognosis. 相似文献
22.
PEMMARAJU NARASIMHA RAO JAMES E. BURDETT JAMES W. CESSAC CECIL M. DiNUNNO DOROTHY M. PETERSON HYUN K. KIM 《Chemical biology & drug design》1987,29(1):118-125
The DL-arylamino acid ethyl ester derivatives of β-(3-pyridyl)-DL-alanine, and β-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide. 相似文献
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24.
眼球孤立性脉络膜血管瘤的HR-MRI表现 总被引:4,自引:0,他引:4
目的 探讨眼球孤立性脉络膜血管瘤的高分辨率磁共振 (HR MRI)影像学特征 ,进一步提高诊断水平。资料与方法 回顾性分析诊断明确的孤立性脉络膜血管瘤 16例共计 17个病灶的位置、数目、形态、大小、MRI信号、强化情况、有无合并视网膜脱离及有无视神经和眼外侵犯等。所有病例均行HR MRI及增强扫描 ,部分病例行脂肪抑制。结果 17个病灶中的 16个呈扁丘状位于眼球内壁的后极。 15个病灶厚度 <5mm ,平均厚度为2 .9mm。病灶边缘清晰 ,T1WI上呈轻度高信号者 16个 ,T2 WI上呈等信号者 15个 ,增强扫描显著强化者有 12个。 3例合并视网膜脱离 ,在T2 WI上多呈等信号 ,T1WI上呈轻度高信号者 ,均无强化。无视神经及眼外侵犯病例。结论 94 %孤立性脉络膜血管瘤的HR MRI表现具有特征性 ,表现为位于眼球内壁后极的较小、基底较宽、边缘清晰的扁丘状病灶。其T1WI信号高于玻璃体 ,T2 WI信号等于玻璃体 ,增强扫描瘤体显著强化。明确其HR MRI影像学特征有助于临床与恶性葡萄膜黑色素瘤相鉴别 ,避免不必要的眼球摘除 相似文献
25.
M. Sand T. Gambichler G. Moussa F. G. Bechara D. Sand P. Altmeyer K. Hoffmann 《Skin research and technology》2006,12(2):114-118
BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary. 相似文献
26.
Mesial temporal sclerosis and volumetric investigations 总被引:2,自引:0,他引:2
M. J. Cook 《Acta neurologica Scandinavica》1994,89(S152):109-114
Volumetric MRI data acquisition permits reliable and accurate measurement of mesial temporal lobe structures. In normal subjects, these structures are very symmetric. A high degree of pathological specificity is associated with the finding of even minor volume asymmetries. Definition in this manner allows precise estimation of both absolute and relative volume differences, and precise anatomical localisation of volume loss within the hippocampus. There are good EEG and clinical correlates with the distribution of volume loss defined on MRI studies. Volumetric assessment is fast, reliable, non-invasive, and a relatively inexpensive component of the pre-operative work-up. It is the method of choice when imaging patients with clinical temporal lobe epilepsy undergoing pre-surgical evaluation. The finding of significant hippocampal volume asymmetry in a patient with clinical temporal lobe seizures being evaluated for epilepsy surgery may obviate the need for alternative sophisticated, invasive, or expensive investigative procedures. At our centre, such MRI allows "fast track" cases to proceed to surgery without further invasive investigations, and is likely to have a dramatic effect on pre-operative evaluation in most centres practising epilepsy surgery. 相似文献
27.
Ictal brain imaging in presurgical evaluation of patients with medically intractable complex partial seizures 总被引:1,自引:0,他引:1
O. N. Markand V. Salanova R. M. Worth H.-M. Park H. H. Wellman Omkar N. Markand M.D 《Acta neurologica Scandinavica》1994,89(S152):137-144
At the Indiana University Medical Center, 99 patients with medically intractable complex partial seizures (MI-CPS) had presurgical evaluation with subsequent anterior temporal lobectomy. The majority of the patients had single photon emission tomography (SPECT) performed interictally as well as during an actual epileptic seizure (ictal scan). Decreased regional cerebral perfusion (rCP) was seen in 54/94 (57%) of the interictal scans corresponding to the eventual site of the surgery. However, ictal scans provided a higher yield; increased rCP in the temporal lobe during an actual seizure was observed in 60/82 (73%) concordant to the side of surgery. SPECT is a useful, noninvasive method of localizing the epilepti-form focus in patients with MI-CPS considered for resective surgery. Both interictal and ictal SPECT need to be performed; combined interictal hypo-perfusion and ictal hyperperfusion in the same focal area are unique to epileptogenic lesions. Ictal SPECT studies can be performed in the majority of patients during the period of continuous video/EEG monitoring with only a little additional effort. Combining the results of functional brain imaging (interictal and ictal SPECT, PET) with clinical semiology of seizures, surface and sphenoidal EEG, magnetic resonance imaging and other non-invasive tests, anterior temporal lobectomy can be recommended in approximately two-thirds of the patients without resorting to potentially dangerous intracranial EEG monitoring. 相似文献
28.
CT多平面重组显示镫骨的方法及应用价值 总被引:2,自引:0,他引:2
目的探讨利用螺旋CT多平面重组(mu ltip lanar reform ation,MPR)技术显示镫骨整体结构的方法和临床价值。方法对50例无耳症状、体征的志愿者行平行枕眶线扫描,应用轴位图像行多方位的MPR。比较轴位MPR、冠状位MPR、矢状位MPR和镫骨斜位MPR显示镫骨整体结构的差异。测量镫骨斜位图像显示层面在轴位定位图像上与矢状面的夹角,在冠状位定位图像上与矢状面的夹角。先天性镫骨异常31例,全部病例经电测听检查均表现有不同程度的传音性耳聋,均行听骨链重建术。结果正常组轴位、冠状位、矢状位均未能显示镫骨弓的整体形态,镫骨斜位MPR图像均直观显示了镫骨弓的整体形态和结构。在轴位定位图像上,镫骨斜位MPR图像显示层面与矢状面的夹角为36°±8°,在冠状位定位图像上与矢状面的夹角为57°±6°。异常组31例,其中一侧小腿缺如3例;镫骨弓不发育3例;镫骨底板增厚与周围骨融合16例;镫骨底板上结构(小头、颈、小腿)完全缺如9例,斜位MPR图像均直观显示其病理改变,轴位、冠状位以及矢状位图像均不能准确显示镫骨发育不良的病理改变。结论镫骨斜位MPR图像,能显示正常镫骨整体结构和镫骨异常改变,对听骨链重建术的术前评价具有重要意义。 相似文献
29.
医疗纠纷的非诉讼解决方式-医疗纠纷ADR 总被引:18,自引:0,他引:18
张海滨 《中国卫生事业管理》2003,19(3):153-155
由于在纠纷解决方面所表现出来的简便,经济,快捷,专业性及保密性强等优点,非诉讼纠纷解决方式(又可译为代替性纠纷解决方式)ADR(Alternative Dispute Resolution)逐渐成为许多国家和地区解决民事纠纷的一大趋势,我国现行医疗纠纷解决机制存在着较多的问题,有待于进一步的改善与完善,根据我国所面临的现实情况,将ADR引入医疗纠纷领域是一条快速,有效地解决医疗纠纷的途径,医疗纠纷的非诉讼纠纷解决方式主要包括仲裁,调解与和解,这3种纠纷解决方式各具特点,适用于不同情况下医疗纠纷的解决。 相似文献
30.
颞浅筋膜瓣包裹高密度聚乙烯-肋软骨复合支架一期耳廓再造术 总被引:3,自引:1,他引:2
目的探寻耳廓再造的良好手术方法。方法将高密度聚乙烯耳基架与肋软骨外耳轮形成复合支架,支架采用颞浅筋膜瓣包裹,颞浅筋膜瓣的表面采用邻近皮瓣和皮片覆盖,完成耳廓再造。结果自2000年1月至2003年8月利用该方法对8例先天性小耳进行耳廓再造术效果良好。结论通过该方法行耳廓再造,具备良好的外形和一定的弹性,外观逼真,手感良好。 相似文献