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111.

The chloroform extract of the air-dried leaves of Alternanthera sessilis afforded a mixture of diastereomers of a new ionone derivative 1 whose structures were elucidated by extensive 1D and 2D NMR spectroscopy and mass spectrometry. Oxidative cleavage of 1 to aldehyde 3 with manganese dioxide confirmed diastereoisomerism arose from a racemic side chain chiral centre. Antimicrobial tests on the mixture of diastereomers and the derivative indicated that they have low activities against Pseudomonas aeruginosa and Trichophyton mentagrophytes.  相似文献   
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Background. Papillary thyroid carcinoma (PTC), follicular thyroid adenoma (FTA), and thyroid nodular hyperplasia (TNH) are the most frequent diseases of the thyroid gland. Previous studies described the involvement of dipeptidyl-peptidase IV (DPPIV/CD26) in the development of thyroid neoplasia and proposed it as an additional tool in the diagnosis/prognosis of these diseases. However, very little is known about the involvement of other peptidases in neoplastic and hyperplastic processes of this gland. Methods. The catalytic activity of 10 peptidases in a series of 30 PTC, 10 FTA, and 14 TNH was measured fluorimetrically in tumour and nontumour adjacent tissues. Results. The activity of DPPIV/CD26 was markedly higher in PTC than in FTA, TNH, and nontumour tissues. Aspartyl aminopeptidase (AspAP), alanyl aminopeptidase (AlaAP), prolyl endopeptidase, pyroglutamyl peptidase I, and aminopeptidase B activities were significantly increased in thyroid neoplasms when compared to nontumour tissues. AspAP and AlaAP activities were also significantly higher in PTC than in FTA and TNH. Conclusions. These data suggest the involvement of DPPIV/CD26 and some cytosolic peptidases in the neoplastic development of PTC and FTA. Further studies will help to define the possible clinical usefulness of AlaAP and AspAP in the diagnosis/prognosis of thyroid neoplasms.  相似文献   
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The aim of this work is to clarify the development and morphology of the juxta‐oral organ (JOO) in rat embryos from Day (E)14 to 19. Furthermore, in the region of the JOO, an analysis was made of the expression of the monoclonal antibody HNK‐1, which recognizes cranial neural‐crest cells. In this study, we report that JOO develops from an epithelial condensation at the end of the transverse groove of the primitive mouth at E14. During E15, it invaginates and is disconnected from the oral epithelium. At E16, the JOO forms an solid epithelial cord with three parts (anterior, middle, and posterior) and is related to the masseter, temporal, medial pterygoid, and tensor veli palatini muscles. During E17‐19, no significant changes were detected in their position. Both the mesenchyme caudal to the anlage of the JOO at E14, as well as the mesenchyme that surrounds the bud of the JOO at E15, expressed positivity for HNK‐1. Our results suggest that the mesenchyme surrounding the JOO at E15 could emit some inductive signal for the JOO to reach its position at E16. This work shows for the first time that the cranial neural‐crest‐derived mesenchyme participates in the development of the JOO. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Pulmonary edema is a frequent condition found in adult patients hospitalized in cardiology wards and intensive care units. Ultrasonography is a diagnostic modality with a high sensitivity for the detection of extravascular lung water, visualized as B lines, and usually caused by cardiogenic or noncardiogenic pulmonary edema. This paper highlights a simple method for the assessment of patients with pulmonary edema, which allows for a differential diagnosis of its possible mechanism and contributes to therapeutic intervention guiding and monitoring.  相似文献   
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