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111.
Neurofibromatosis type 2 is caused by mutations in the NF2 tumor suppressor gene. The NF2 gene encodes a 595‐aminoacid protein, presumably functioning as a membrane‐organizing element. Theoretically, the majority of mutations found in the NF2 gene should lead to a truncated protein product. Using immunoprecipitation with an antibody raised to N‐terminal sequences of the NF2 protein, the authors sought to demonstrate the presence of truncated NF2 proteins in tumors. From 17 of 19 tumors (14 meningiomas and five schwannomas), 12 of which have previously been shown to harbor truncating NF2 mutations, wild‐type NF2 protein was immunopreci‐pitated. From two tumors no protein was precipitated. Truncated NF2 proteins were not observed. The authors conclude that mutant NF2 proteins are unstable and undergo accelerated degradation.  相似文献   
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尽管卒中的预防、诊断、治疗和康复已取得一些进展,但卒中在美国仍然是第三大死亡原因和长期残疾的主要原因.每年约有70万人新发或复发卒中[1].在过去10年里,急性卒中诊治的一些进展,包括纤溶和其他短期疗法的引入,突出显示了急诊医疗服务(emergency medical services,EMS)机构和急诊医疗服务体系(emergency medical services systems,EMSS)在优化卒中医疗中的关键作用[2-7].  相似文献   
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Endothelial dysfunction (ED) is characterized by an imbalance between vasodilator and vasoconstriction agents. Several pathological conditions clinically diagnosed in childhood and adolescence are characterized by ED and increased risk for early development of microangiopathic and macroangiopathic impairment, in particular type 1 diabetes mellitus (T1DM), T2DM, obesity, metabolic syndromeand pituitary dysfunction associated to various endocrinopathies. More recently insulin resistance following chemotherapy or radiotherapy for tumors, bone marrow transplantation for hematological malignancies (i.e., cancer survivors), or immunosuppressive treatment for solid organ transplantation has been observed. Assessment of ED by means of non-invasive techniques is the gold standard for early ED detection before clinical manifestation. It is aimed to recognize patients at risk and to avoid the development and progression of more serious illnesses. Reactive hyperemia-peripheral artery tonometry is a noninvasive technique to assess peripheral endothelial function by measuring modifications in digital pulse volume during reactive hyperemia, and represents a non-invasive, reproducible and operator-independent tool able to detect precocious ED. This narrative review aimed to provide an overview of the most important papers regarding ED detection by EndoPat 2000 in children and adolescents with different endocrine diseases. A comprehensive search of English language articles was performed in the MEDLINE database without using other search filters except the publication interval between 2005 and 2020.  相似文献   
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Objectives :The aim of this study was to compare the accuracy of vertical root fracture (VRF) detection using three tomography devices and two software systems in teeth with different endodontic fillings.Methods:The sample consisted of 45 premolars divided into 3 groups: No filling (NF, n=15); Gutta percha (GP, n=15) and Metallic Post (MP, n=15). Cone-beam computed tomography (CBCT) images were acquired in Kodak 9000 3D, Orthopantomography 300 (OP300) and PreXion 3D devices, before and after induced root fractures. Two oral radiologists analyzed all images using InVivoDental and e-Vol DX software systems. The analysis was repeated after 15 days in 30% of the sample. Data analysis compared receiver operating characteristic (ROC) curves, as well the areas under the ROC curves. Accuracy, sensitivity, specificity, positive and negative predictive value were calculated according to each tomographic device and software. Intra- and interexaminer reliability were tested using the Kappa coefficient.Results:The highest accuracy was seen in the image set from the PreXion 3D, using InVivo (0.96) or e-Vol DX (0.92) in image analysis. The OP300 device presented a similar performance of the PreXion 3D in teeth with different endodontic fillings. When using e-Vol DX, the accuracy of Kodak 9000 3D improved from 0.62 to 0.74.Conclusions:The PreXion 3D device is the most accurate when detecting VRF, with a performance similar to the OP300 in endodontic filled teeth. Kodak 9000 3D is indicated for teeth without fillings, with better accuracy using e-Vol DX software.  相似文献   
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This communication reports the histological structure of loop recessions of extraocular muscles from seven patients. In all cases the loops formed pseudotendons in which the typical histological structure was well established by four months. Subsequently, moulding of these pseudotendons occurred with improved alignment of collagen and decrease in vascularity. By three and a half years after the operation the pseudotendon had acquired a very close resemblance to true tendon.  相似文献   
118.
The ability of the monocyte monolayer assay (MMA) and the chemiluminescence test (CLT) to predict the clinical significance of alloantibodies associated with hemolytic disease of the newborn (HDN) was assessed by the use of 22 well-characterized antisera– predominantly anti-D–from alloimmunized pregnant women. Seventeen sera were obtained before delivery from women whose infants were antigen positive for the antibody specificities identified in the maternal serum. With testing of these 17 sera by MMA, 10 results were in agreement with the presence or absence of HDN, but there were 5 false- positive and 2 false-negative results. With the CLT, 16 results were in agreement with the presence or absence of HDN, and there was 1 false- negative result. Five sera were obtained from women whose infants were antigen negative for the antibody specificities identified in the maternal serum. The CLT and the MMA were both subject to false-positive results with these sera. These results suggest that the CLT may be more valuable than the MMA as a noninvasive test for predicting the clinical significance of alloantibodies in HDN.  相似文献   
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