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Two Myrtus communis varieties (var. italica and baetica) were studied in order to investigate their essential oil yield and composition. Essential oil yield varied in leaves, fruits and stems. So, in leaves, it was 0.5% for italica and 0.3% for baetica and was higher than in fruits and stems with respectively 0.1% and 0.04% for italica and 0.07% and 0.03% for baetica. The essential oil analysis performed by GC and GC/MS showed a composition characterized by a high percentage of monoterpene hydrocarbons in leaves, largely due to alpha-pinene with 51.3% for italica and 27.7% for baetica; 1,8-cineole, the alone compound of ether class, was predominant in fruits and stems with respectively 31.6% and 34.7% for italica and 19.8% and 25.8% for baetica. 相似文献
173.
Biology Bulletin - Due to its wide industrial use, cadmium (Cd) is considered a serious environmental pollutant. Halophytes, such as Atripex species, are model candidates to remediate heavy... 相似文献
174.
Intensity normalization is an important pre-processing step in the study and analysis of DaTSCAN SPECT imaging. As most automatic supervised image segmentation and classification methods base their assumptions regarding the intensity distributions on a standardized intensity range, intensity normalization takes on a very significant role. In this work, a comparison between different novel intensity normalization methods is presented. These proposed methodologies are based on Gaussian Mixture Model (GMM) image filtering and mean-squared error (MSE) optimization. The GMM-based image filtering method is achieved according to a probability threshold that removes the clusters whose likelihood are negligible in the non-specific regions. The MSE optimization method consists of a linear transformation that is obtained by minimizing the MSE in the non-specific region between the intensity normalized image and the template. The proposed intensity normalization methods are compared to: i) a standard approach based on the specific-to-non-specific binding ratio that is widely used, and ii) a linear approach based on the α-stable distribution. This comparison is performed on a DaTSCAN image database comprising analysis and classification stages for the development of a computer aided diagnosis (CAD) system for Parkinsonian syndrome (PS) detection. In addition, these proposed methods correct spatially varying artifacts that modulate the intensity of the images. Finally, using the leave-one-out cross-validation technique over these two approaches, the system achieves results up to a 92.91% of accuracy, 94.64% of sensitivity and 92.65 % of specificity, outperforming previous approaches based on a standard and a linear approach, which are used as a reference. The use of advanced intensity normalization techniques, such as the GMM-based image filtering and the MSE optimization improves the diagnosis of PS. 相似文献
175.
Brahim Arkoun Ludovic Dumont Jean-Pierre Milazzo Agathe Way Amandine Bironneau Julien Wils Bertrand Macé Nathalie Rives 《PloS one》2015,10(2)
Testicular tissue freezing has been proposed for fertility preservation in pre-pubertal boys. Thawed frozen testicular tissue must undergo a maturation process to restore sperm production. The purpose of the current study was to evaluate the ability of retinol to improve the in vitro differentiation of pre-pubertal mouse spermatogonial stem cells into sperm. Testes from pre-pubertal mice, aged 2.5 and 6.5 days post-partum, were cultured on agarose gel at a gas-liquid interphase for 34, 38 and 60 days (D) and for 16, 30 and 36 D respectively. Assessment of basal medium (BM) supplemented with retinol (RE) alone, FSH/LH alone or a combination of both, was performed. Stereological analyses and tissue lesion scoring were performed at the culture time points indicated above. Sperm production was quantified at D30 and D34 after mechanical dissection of the testicular tissues. FSH/LH significantly increased the percentage of round spermatids at D30 and D38, when compared to BM alone. However, RE significantly increased the percentages of round but also elongated spermatids at D30 and D34. Moreover, RE significantly increased the number of spermatozoa per milligram of tissue at D30 and D34 when compared to BM. Therefore, RE improved the in vitro production of spermatids and spermatozoa from pre-pubertal SSCs during the first wave of spermatogenesis. The use of RE could be a useful tool for in vitro spermatogenesis from pre-pubertal human testicular tissue. 相似文献
176.
Hiltermann JT Lapperre TS van Bree L Steerenberg PA Brahim JJ Sont JK Sterk PJ Hiemstra PS Stolk J 《Free radical biology & medicine》1999,27(11-12):1448-1454
We investigated correlations between ozone-induced increases in inflammatory markers in induced sputum and in bronchial lavage fluid. Sixteen volunteers with intermittent asthma participated in a placebo-controlled parallel study with two exposures. Six days before and 16 h after the first exposure to ozone (0.4 ppm during 2 h) sputum was induced with hypertonic saline. This resulted in a significant increase in the sputum levels of eosinophil cationic protein (ECP; 1.8-fold; p = .03), neutrophil elastase (5.0-fold; p = .005) and the total cell number (1.6-fold; p = .02). After 4 weeks, a second exposure was randomized for air or ozone. Six days before and 16 h after the second exposure a bronchial lavage was performed. ECP values in sputum and in bronchial lavage fluid obtained after ozone correlated significantly (Rs = .79; p = .04), as did interleukin-8 (IL-8) values (Rs = .86; p = .01), and the percentage eosinophils (Rs = .89; p = .007). Moreover, the ozone-induced changes in percentage eosinophils observed in sputum and lavage fluid were highly correlated (Rs = .93; p = .003). In conclusion, changes in eosinophils, IL-8, and ECP markers induced by ozone and measured in sputum reflect the inflammatory responses in the lower airways of asthmatics, and may provide a noninvasive tool in epidemiologic studies on air pollution and asthma. 相似文献
177.
Ischemic retinopathies are clinically well-defined chronic microvascular complications characterized by gradually progressive alterations in the retinal microvasculature and a compensatory aberrant neovascularization of the eye. The subsequent metabolic deficiencies result in structural and functional alterations in the retina which is highly susceptible to injurious stimuli such as diabetes, trauma, hyperoxia, inflammation, aging and dysplipidemia. Emerging evidence indicates that an effective therapy may require targeting multiple components of the angiogenic pathway. Conceptually, mircoRNA (miRNA)-based therapy provides the rationale basis for an effective antiangiogenic treatment. miRNAs are an evolutionarily conserved family of short RNAs, each regulating the expression of multiple protein-coding genes. The activity of specific miRNAs is important for vascular cell signaling and blood vessel formation and function. Recently, important progress has been made in mapping the miRNA-gene target network and miRNA-mediated gene expression control. Here we highlight the latest findings on angiogenic and antiangiogenic miRNAs and their targets as well as potential implications in ocular neovascular diseases. Emphasis is placed on how specific vascular-enriched miRNAs regulate cell responses to various cues by targeting several factors, receptors and/or signaling molecules in order to maintain either vascular function or dysfunction. Further improvement of our knowledge in not only miRNA specificity, turnover, and transport but also how miRNA sequences and functions can be altered will enhance the therapeutic utility of such molecules. 相似文献
178.
Lakhrissi B Benksim A Massoui M Essassi el M Lequart V Joly N Beaupère D Wadouachi A Martin P 《Carbohydrate research》2008,343(3):421-433
New water-soluble benzimidazolone derivatives were synthesized. In the first approach, di-N-glycosyl and mono-N-alkyl-N-glycosyl compounds were obtained by grafting C-6-activated glycosides onto benzimidazolone. In the second approach, benzimidazolone derivatives bearing a glucosyl unit were synthesized using an efficient glycosylation method. Every compound structure was confirmed by means of NMR spectroscopy and elemental analysis. The preliminary surfactant properties of some compounds were evaluated. 相似文献
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180.