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排序方式: 共有1680条查询结果,搜索用时 15 毫秒
71.
Martin Stepan Teresa Cobo Ivana Musilova Helena Hornychova Bo Jacobsson Marian Kacerovsky 《PloS one》2016,11(3)
Objective
This study evaluated maternal C-reactive protein (CRP) as a predictor of microbial invasion of the amniotic cavity (MIAC) and histological chorioamnionitis (HCA) in women with preterm prelabor rupture of the membranes (PPROM) before and after 32 weeks of gestation.Methods
This study was a prospective observational cohort study of 386 women. Maternal serum CRP concentrations were evaluated, and amniotic fluid samples were obtained via transabdominal amniocentesis at the time of admission. Placentas underwent histopathological examination after delivery. MIAC was defined based on a positive PCR for Ureaplasma species, Mycoplasma hominis and Chlamydia trachomatis and/or positive 16S rRNA gene amplification. HCA was defined based on the Salafia classification.Results
Maternal CRP was significantly higher in women with MIAC and HCA (median 9.0 mg/l) than in women with HCA alone (median 6.9 mg/l), MIAC alone (median 7.4 mg/l) and without MIAC or HCA (median 4.5 mg/l) (p<0.0001). CRP was a weak predictor of the occurrence of MIAC and HCA before and after 32 weeks of gestation. Only the 95th percentile of CRP and PPROM before 32 weeks exhibited a false-positive rate of 1%, a positive predictive value of 90% and a positive likelihood ratio of 13.2 to predict MIAC and HCA. However, the low sensitivity of 15% limits the clinical utility of this detection.Conclusion
CRP is a poor predictor of the occurrence of MIAC and HCA, even at early gestational ages. 相似文献72.
Genetic diversity and morphological variability in the Balkan endemic Campanula secundiflora s.l. (Campanulaceae) 下载免费PDF全文
Ivana Janković Zlatko Šatović Zlatko Liber Nevena Kuzmanović Ivan Radosavljević Dmitar Lakušić 《Botanical journal of the Linnean Society. Linnean Society of London》2016,180(1):64-88
We reconstructed the relationships among populations of Campanula secundiflora s.l. and closely related and geographically close populations of C. austroadriatica and C. versicolor. Based on analyses of microsatellite DNA data, the investigated populations have high overall genetic diversity and abundant allelic variation over seven investigated loci. Bayesian model‐based clustering identified four clearly differentiated genetic groups of populations. The genetic differentiation was reflected by morphological differentiation, allowing us to propose a new taxonomic treatment of the constituents of C. secundiflora s.l. The populations distributed in south‐western Serbia and north‐eastern Montenegro were included in C. secundiflora. A new species, C ampanula montenegrina sp. nov. , distributed in the continental part of Montenegro and the northern part of Albania is described. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2016, 180 , 64–88. 相似文献
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Effect of Cultivation Time on Production of Antifungal Metabolite(s) by Streptomyces hygroscopicus in Laboratory‐Scale Bioreactor 下载免费PDF全文
Ivana Tadijan Jovana Grahovac Jelena Dodić Mila Grahovac Siniša Dodić 《Journal of Phytopathology》2016,164(5):310-317
Biological control agents offer one of the best alternatives to reduce the use of pesticides . Fungi from the genera Alternaria, Colletotrichum and Fusarium are listed among the most important storage pathogens of apple fruits. During storage, transport and marketing, pathogenic fungi can cause significant losses of apple fruits. This investigation studied the potential of Streptomyces hygroscopicus as a biocontrol agent against pathogenic fungi obtained from apple fruit samples expressing rot symptoms. Production of antifungal metabolites by S. hygroscopicus was carried out in 3‐l bench‐scale bioreactor (Biostat® Aplus, Sartorius AG, Germany) during 7 days. Fermentation was carried out at 27°C with aeration rate of 0.5 vvm and agitation rate of 200 rpm. The aim was to analyse bioprocess parameters of batch biofungicide production in medium containing glucose as a carbon source and to examine at which stage of bioprocess production of antifungal metabolite(s) against six phytopathogenic fungi occurs. In vitro antifungal activity of the produced metabolites against six fungi of the genera Colletotrichum, Fusarium and Alternaria grown on potato dextrose agar were determined every 24 h using wells technique. Antifungal activity of cell‐free culture filtrate and filtrate treated with high temperature were tested. The filtrate treated with high temperature did not show any antifungal activity suggesting that active components are thermo unstable. Stationary phase of growth occurred between the third and fourth day of cultivation when production of secondary metabolites begins. Obtained results showed that maximal antifungal activity is achieved on fifth and sixth day of S. hygroscopicus cultivation under defined conditions (inhibition zone diameter higher than 30 mm for all test fungi). 相似文献
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Kristýna Nmejcov Ivana Tich Michaela Brt Ondej Kodet Miroslav Dra Radek Jaka Romana Michlkov Pavel Dundr 《Pigment cell & melanoma research》2019,32(3):412-423
The objective of our study was to compare the five different scoring methods of tumor‐infiltrating lymphocytes (TILs) assessment in a group of 213 cases of superficial spreading and nodular melanoma. The scoring methods include (a) Clark scoring; (b) Melanoma Institute Australia system; (c) scoring system used in the study of Saldanha et al.; (d) scoring system used in the TCGA study and modified by Park et al.; and (e) the system recently proposed by the “International Immuno‐Oncology Biomarker Working Group” for TILs scoring in all solid tumors. Prediction of survival with three main outcomes—disease‐specific‐free survival, local recurrence‐free survival, and distant metastasis‐free survival—was evaluated. The prognostic value of TILs showed statistical significance in univariate analysis regarding all three of the outcomes only for three of the five evaluated methods; the Clark scoring, the Melanoma Institute Australia system, and the system proposed by the “International Immuno‐Oncology Biomarker Working Group”. However, in multivariate analysis with covariants including Breslow thickness, type of melanoma, location, sex, and age, we did not find TILs to be an independent prognostic factor. 相似文献
77.
Ayelén Ivana Pesce Viglietti Guillermo Hernán Giambartolomei María Victoria Delpino 《Microbes and infection / Institut Pasteur》2019,21(7):287-295
Osteoarticular brucellosis is the most frequent complication of active disease. A large amount of cells in bone are osteocytes. Since bone remodeling process is regulated by hormones we sought to study the effect of cortisol and DHEA in Brucella abortus-infected osteocytes. Cortisol treatment inhibited the expression of IL-6, TNF-α, MMP-2 and RANKL in B. abortus-infected osteocytes. DHEA could reverse the inhibitory effect of cortisol on MMP-2 production. B. abortus infection inhibited connexin 43 (Cx43) expression in osteocytes. This expression was increased when cortisol was incorporated during the infection and DHEA treatment partially reversed the effect of cortisol. Osteocytes-infected with B. abortus induced osteoclast's differentiation. Yet, the presence of cortisol, but not DHEA, during osteocyte infection inhibited osteoclastogenesis. Glucocorticoid receptor (GR) is implicated in the signaling of cortisol. Infection with B. abortus was able to increase GRα/β ratio. Levels of intracellular cortisol are not only dependent on GR expression but also a result of the activity of the isoenzymes 11β-hydroxysteroid dehydrogenase (11β-HSD)-1 (cortisone to cortisol conversion), 11β-HSD2 (cortisol to cortisone conversion). B. abortus infection increased 11β-HSD 1/2 ratio and cortisone mimicked the effect of cortisol. Our results indicated that cortisol and DHEA could modulate osteocyte responses during B. abortus infection. 相似文献
78.
González-Bergonzoni Ivan D’Anatro Alejandro Vidal Nicolás Stebniki Samanta Tesitore Giancarlo Silva Ivana Teixeira de Mello Franco 《Ecosystems》2019,22(8):1736-1753
Ecosystems - The origin of resources supporting metazoan biomass in rivers has long been a subject of debate. The river wave concept (RWC) postulates that the energetic basis of food webs varies... 相似文献
79.
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Lance J. Miller Jamie A. Ivy Greg A. Vicino Ivana G. Schork 《Journal of applied animal welfare science : JAAWS》2019,22(2):188-196
To improve the welfare of nonhuman animals under professional care, zoological institutions are continuously utilizing new methods to identify factors that lead to optimal welfare. Comparative methods have historically been used in the field of evolutionary biology but are increasingly being applied in the field of animal welfare. In the current study, data were obtained from direct behavioral observation and institutional records representing 80 individual animals from 34 different species of the order Carnivora. Data were examined to determine if a variety of natural history and animal management factors impacted the welfare of animals in zoological institutions. Output variables indicating welfare status included behavioral diversity, pacing, offspring production, and infant mortality. Results suggested that generalist species have higher behavioral diversity and offspring production in zoos compared with their specialist counterparts. In addition, increased minimum distance from the public decreased pacing and increased offspring production, while increased maximum distance from the public and large enclosure size decreased infant mortality. These results have implications for future exhibit design or renovation, as well as management practices and priorities for future research. 相似文献