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101.
Francesc Feliu Juan C. Rueda Jorge Escuder Fernando Gris Andrea Jiménez Vicente Vicente 《International surgery》2013,98(4):392-398
Intussusception is a rare cause of adult intestinal obstruction. Clinical manifestations are not specific, which makes a preoperative diagnosis difficult to establish and often causes delay. We report a case of acute intestinal obstruction due to ileocolic intussusception. An emergency laparoscopy was performed revealing an obstructive mass at the ileocecal region resulting from an appendicular tumor. A right hemicolectomy was conducted. The pathologic examination of the resected sample concluded the mass comprised an appendicular mucinous cystoadenoma. We discuss the clinical features, preoperative diagnosis, and surgical strategies of adult intussusception, as well as the uncommon finding of an appendicular mucinous tumor as its causative lesion, with a review of the available literature. 相似文献
102.
Elies Fuster‐Garcia Salvador Tortajada Javier Vicente Montserrat Robles Juan M. García‐Gómez 《NMR in biomedicine》2013,26(5):578-592
The current challenge in automatic brain tumor classification based on MRS is the improvement of the robustness of the classification models that explicitly account for the probable breach of the independent and identically distributed conditions in the MRS data points. To contribute to this purpose, a new algorithm for the extraction of discriminant MRS features of brain tumors based on a functional approach is presented. Functional data analysis based on region segmentation (RSFDA) is based on the functional data analysis formalism using nonuniformly distributed B splines according to spectral regions that are highly correlated. An exhaustive characterization of the method is presented in this work using controlled and real scenarios. The performance of RSFDA was compared with other widely used feature extraction methods. In all simulated conditions, RSFDA was proven to be stable with respect to the number of variables selected and with respect to the classification performance against noise and baseline artifacts. Furthermore, with real multicenter datasets classification, RSFDA and peak integration (PI) obtained better performance than the other feature extraction methods used for comparison. Other advantages of the method proposed are its usefulness in selecting the optimal number of features for classification and its simplified functional representation of the spectra, which contributes to highlight the discriminative regions of the MR spectrum for each classification task. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
103.
Fabianni M. Apolonio Annalisa Mazzoni Valeria Angeloni Polliana M. C. Scaffa Spartaco Santi Vicente de Paulo A. Saboia Franklin R. Tay David H. Pashley Lorenzo Breschi 《European journal of oral sciences》2017,125(2):168-172
Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one‐step self‐etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP‐2 and MMP‐9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one‐step adhesive system. The MMP‐2 and MMP‐9 activities in dentin treated with the one‐step adhesive, Adper Easy Bond, were quantified using an enzymatic activity assay system. The MMP activities within the hybrid layer created by the one‐step adhesive tested were also evaluated using in situ zymography. The enzymatic assay revealed an increase in MMP‐2 and MMP‐9 activities after treatment with adhesive. In situ zymography indicated that gelatinolytic activity is present within the hybrid layer created with the one‐step self‐etch adhesive. The host‐derived gelatinases were localized within the hybrid layer and remained active after the bonding procedure. It is concluded that the one‐step self‐etch adhesive investigated activates endogenous MMP‐2 and MMP‐9 with the dentin matrix, which may cause collagen degradation over time. 相似文献
104.
Fátima Jorge Miguel A. Carretero Vicente Roca Robert Poulin Ana Perera 《Parasitology research》2013,112(12):4001-4007
Parasitological analyses are often based on invasive methodologies, involving host sacrifice, raising ethical and conservation issues. However, alternative non-invasive approaches may not be always applicable due to the location of the parasite in the host tissue or the quality and reliability of the non-invasive sample per se. In this study, we compare the differences in detectability of intestinal parasites in reptiles using the classical invasive approach (intestine dissection), versus a non-invasive procedure (faecal examination), collected from the same individual host. Our results showed significantly lower detectability of helminths in faeces versus the intestine. Moreover, the number of parasites found in faeces was not explained either by the intensities found in the respective intestine or by the host identity. Several factors may explain the lack of association between the two types of samples, but more importantly, our results highlight the randomness of the presence of parasites in faeces. Even if it is not recommended that comparative studies of either parasite abundance or parasite communities be conducted on the basis of faecal samples, there are other types of studies (i.e. genetic) that can be performed with this source of information, thus avoiding the sacrifice of the host. Due to their wide spectrum of life stages and localization in the host tissue, parasites are challenging candidates for non-invasive sampling and consequently, parasitological methodologies should be carefully selected according to the objective of the study. 相似文献
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