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In humans, intermittent and continuous theta‐burst stimulation (iTBS and cTBS) elicit long‐term changes in motor‐evoked potentials (MEPs) reflecting long‐term potentiation (LTP)‐ and depression (LTD)‐like plasticity in the primary motor cortex (M1). In this study, we used TBS to investigate M1 plasticity in patients with MSA. We also assessed whether responses to TBS reflect M1 excitability as tested by short‐interval intracortical inhibition (SICI), intracortical facilitation (ICF), short‐interval intracortical facilitation (SICF), and the input/output curves. We studied 20 patients with MSA and 20 healthy subjects (HS). Patients were clinically evaluated with the Unified Multiple System Atrophy Rating Scale. The left M1 was conditioned with TBS. Twenty MEPs were recorded from the right first dorsal interosseous muscle before TBS and 5, 15, and 30 minutes thereafter. In a subgroup of 10 patients, we also tested MEPs elicited by SICI, ICF, SICF, and input/output curves, before TBS. Between‐group analysis of variance showed that at all time points after iTBS MEPs increased, whereas after cTBS they decreased only in HS. In both subgroups tested, patients with predominant parkinsonian and cerebellar features, iTBS and cTBS left MEPs unchanged. MSA patients had reduced SICI, but normal ICF, SICF, and input/output curves. No correlation was found between patients' clinical features and responses to TBS and M1 excitability variables. These findings suggest impaired M1 plasticity in MSA. © 2013 International Parkinson and Movement Disorder Society  相似文献   
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The aim of this case report was to present a case of multiple calcified tuberculous lymph nodes found on a panoramic radiograph coincidently diagnosed in an endodontic clinic. A detailed discussion on the differential diagnosis of similar such calcification found in the same region is also presented. A 14‐year‐old girl was referred to our department with the complaint of painless swelling in the left side of the lower jaw. Clinical and radiographical examinations were performed, leading to the initial diagnosis of chronic periapical abscess. The patient's medical history was re‐evaluated. Advanced imaging and excisional biopsy were performed in order to confirm the final diagnosis. Regarding the presenting signs and symptoms of bilateral carious mandibular molars, a periapical inflammatory process was considered in the provisional diagnosis. A thorough examination and investigations were suggestive of cervical tuberculous lymphadenitis (scrofula), and the patient underwent excision of the same. The clinician should consider the possibility of chronic granulomatous inflammatory lesions in the differential diagnosis of radiopaque lesions.  相似文献   
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Background Photodynamic therapy (PDT) with 5‐aminolaevulinic acid (ALA) or its methylester [methyl‐5‐aminolaevulinate (MAL) or 5‐amino‐4‐oxopentanoate] was recently ranked as first‐line therapy for the treatment of actinic keratosis (AK) and is an accepted therapeutic option for the treatment of neoplastic skin diseases. BF‐200 ALA (Biofrontera Bioscience GmbH, Leverkusen, Germany) is a gel formulation of ALA with nanoemulsion for the treatment of AK which overcomes previous problems of ALA instability and improves skin penetration. Objectives To evaluate the efficacy and safety of PDT of AKs with BF‐200 ALA in comparison with a registered MAL cream and with placebo. Methods The study was performed as a randomized, multicentre, observer‐blind, placebo‐controlled, interindividual trial with BF‐200 ALA, a registered MAL cream and placebo in a ratio of 3 : 3 : 1. Six hundred patients, each with four to eight mild to moderate AK lesions on the face and/or the bald scalp, were enrolled in 26 study centres in Germany, Austria and Switzerland. Patients received one PDT. If residual lesions remained at 3 months after treatment, PDT was repeated. Results PDT with BF‐200 ALA was superior to placebo PDT with respect to patient complete clearance rate (78·2% vs. 17·1%; P < 0·0001) and lesion complete clearance rate (90·4% vs. 37·1%) at 3 months after the last PDT. Moreover, superiority was demonstrated over the MAL cream regarding the primary endpoint patient complete clearance (78·2% vs. 64·2%; P < 0·05). Significant differences in the patient and lesion complete clearance rates and severity of treatment‐related adverse events were observed for the narrow‐ and broad‐spectrum light sources. Conclusions BF‐200 ALA is a very effective, well‐tolerated new formulation for AK treatment with PDT and is superior to a registered MAL medication. Efficacies and adverse events vary greatly with the different light sources used.  相似文献   
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Schafer  AI; Zavoico  GB; Loscalzo  J; Maas  AK 《Blood》1987,69(5):1504-1507
Endothelial cell prostacyclin (PGI2) inhibits platelet activation by raising platelet cyclic AMP. Previously, platelet activation was also shown to be blocked by plasmin formed by endothelium-derived tissue plasminogen activator (TPA). We have now studied interactions between PGI2 and plasmin in the control of platelet function. PGI2 and plasmin cause synergistic inhibition of thrombin- and ADP-induced aggregation of washed platelets. Inhibition by PGI2 is similarly potentiated by TPA added to platelet-rich plasma to generate plasmin. Thrombin-stimulated rise in platelet cytosolic Ca2+, measured by fura2 fluorescence, and thromboxane A2 formation, measured by radioimmunoassay (RIA), are likewise synergistically inhibited by PGI2 and plasmin. Plasmin neither increases nor potentiates PGI2-stimulated increases in platelet cyclic AMP. Thus, PGI2 and plasmin cause synergistic inhibition of platelet activation by both cyclic AMP-dependent and independent mechanisms. This interaction between two different endothelium-derived products may play an important role in localizing the hemostatic plug to a site of vascular injury by preventing further thrombin-mediated accrual of platelets.  相似文献   
38.
Mark AK  高立  杨敏洁 《放射学实践》2006,21(12):1292-1295
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,…  相似文献   
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GL Reed  AK Houng 《Circulation》1999,99(2):299-304
BACKGROUND: The resistance of thrombi to fibrinolysis induced by plasminogen activators remains a major impediment to the successful treatment of thrombotic diseases. This study examines the contribution of activated factor XIII (factor XIIIa) to fibrinolytic resistance in experimental pulmonary embolism. METHODS AND RESULTS: The fibrinolytic effects of specific inhibitors of factor XIIIa-mediated fibrin-fibrin cross-linking and alpha2-antiplasmin-fibrin cross-linking were measured in anesthetized ferrets with pulmonary emboli. Five experimental groups were treated with heparin (100 U/kg) and/or tissue plasminogen activator (TPA, 1 mg/kg) and the percent (mean+/-SD) lysis of emboli was determined: (1) control, normal factor XIIIa activity (14.1+/-4. 8% lysis); (2) inhibited factor XIIIa activity (42.7+/-7.4%); (3) normal factor XIIIa activity+TPA (32.3+/-7.7%); (4) inhibited factor XIIIa activity+TPA (76.0+/-11.9%); and (5) inhibited alpha2-antiplasmin-fibrin cross-linking+TPA (54.7+/-3.9%). Inhibition of factor XIIIa activity increased endogenous lysis markedly (group 1 versus 2; P<0.0001), to a level comparable to that achieved with TPA (group 2 versus 3; P<0.05). Among groups receiving TPA, selective inhibition of factor XIII-mediated alpha2-antiplasmin-fibrin cross-linking enhanced lysis (group 3 versus 5; P<0.0005). Complete inhibition of factor XIIIa also amplified lysis (group 3 versus 4; P<0.0001) and had greater effects than inhibition of alpha2-antiplasmin cross-linking alone (group 4 versus 5; P<0.0005). No significant fibrinogen degradation occurred in any group. CONCLUSIONS: Factor XIIIa-mediated fibrin-fibrin and alpha2-antiplasmin-fibrin cross-linking both caused experimental pulmonary emboli to resist endogenous and TPA-induced fibrinolysis. This suggests that factor XIIIa may play a critical role in regulating fibrinolysis in human thrombosis.  相似文献   
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