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161.
Capecitabine, a fluoropyrimidine derivative, is an orally administered drug that delivers 5-fluorouracil (5-FU) selectively to the tumour. The drug has demonstrated activity in metastatic colorectal cancer. We describe a male patient receiving capecitabine therapy with typical chest pain and electrocardiographic changes consistent with STsegment elevation myocardial infarction. Capecitabine-induced cardiotoxicity may develop in patients who have had a previous episode of 5-FU-induced cardiotoxicity. Capecitabine-induced cardiotoxicity is a rare condition that may lead to diagnostic and therapeutic dilemmas. (Neth Heart J 2009;17:277–80.) 相似文献
162.
Adrian-Ştefan Andrei Andreea Baricz Manuela Păuşan Vasile Muntean Cosmin Ionel Sicora Mircea Alexe 《Geomicrobiology journal》2017,34(2):130-138
Dating from the Middle Miocene, the massive halite deposits lying beneath the Transylvanian Basin (Central Romania) have been valuable mineral resources quarried for millennia. Among the numerous hypersaline pit lakes that resulted from this mining, Brâncoveanu Lake is unique by its extreme salinity. Assessment of physicochemical variables, water chemistry and trophic status indicated that Brâncoveanu Lake is a permanently stratified, pH-neutral, NaCl-rich and eutrophied system. We investigated the abundance, molecular diversity and vertical distribution of archaeal community by culture-independent approaches. Additionally, the most relevant environmental parameters shaping the archaeal community composition were evaluated by statistical methods. Archaea appeared to largely outnumber Bacteria; altogether the great prevalence of Halobacteriaceae-related sequences could imply a major contribution of this group to the biogeochemical carbon turnover. The fairly distinct composition of archaeal communities reflects the lake's physicochemical stratification. Among the limnological factors, salinity and oxygen showed a significant impact on determining the composition and structure of archaeal assemblages. Furthermore, Brâncoveanu Lake might harbor novel microorganisms such as members of the recently described phylum Nanohaloarchaea. Overall, this study reported the occurrence of halophilic Archaea in a little explored hydrogeochemical system and provided a better insight into geomicrobiology of meromictic hypersaline pit lakes. 相似文献
163.
Phytochemical Profile and Biological Activities of Helianthemum canum l. baumg. from Turkey
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In the current study, antioxidant, antibacterial activities, and the phenolic compositions of extracts from Helianthemum canum L. Baumg . (Apiaceae) aerial parts were investigated for the first time. The H . canum was extracted with 70% methanol (HCM eOH ) and water (HCW ). Both extracts were determined by total phenolic contents (3 mg/ml), flavonoids (1.5 mg/ml), flavonols (1.5 mg/ml), qualitative–quantitative compositions, iron (II ) chelation activities (0.1 – 5 mg/ml), free radical scavenging activities (DPPH ?: 0.01 – 0.6 mg/ml and ABTS +?: 0.125 – 0.5 mg/ml) and the effect upon inhibition of β ‐carotene/linoleic acid co‐oxidation (1 mg/ml). The peroxidation level was also determined using the thiobarbituric acid method (0.01 – 1.5 mg/ml). The results of the activity tests given as IC 50 values were estimated from non‐linear algorithm and compared with standards. Antibacterial activities of extracts and standards were evaluated against Gram‐ negative and ‐positive ten standard strains using disc diffusion and broth microdilution methods. The MIC results (312.5 – 2500 μg/ml) against tested microorganisms varied from 625 to 2500 μg/ml. In HPLC analysis, 3,5‐dihydroxybenzoic acid was found as the main substance in both extracts. These results showed that HCM eOH was richer in phenolic compounds (284.13 ± 0.30 mg GAE /g extract) from HCW (244.55 ± 0.35 mg GAE /g extract). In conclusion, H . canum extracts showed in vitro antibacterial and antioxidant activities. 相似文献
164.
Conservation status of freshwater mussels in Europe: state of the art and future challenges
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Manuel Lopes‐Lima David C. Aldridge Rafael Araujo Jakob Bergengren Yulia Bespalaya Erika Bódis Lyubov Burlakova Dirk Van Damme Karel Douda Elsa Froufe Dilian Georgiev Clemens Gumpinger Alexander Karatayev Ümit Kebapçi Ian Killeen Jasna Lajtner Bjørn M. Larsen Rosaria Lauceri Anastasios Legakis Sabela Lois Stefan Lundberg Evelyn Moorkens Gregory Motte Karl‐Otto Nagel Paz Ondina Adolfo Outeiro Momir Paunovic Vincent Prié Ted von Proschwitz Nicoletta Riccardi Mudīte Rudzīte Māris Rudzītis Christian Scheder Mary Seddon Hülya Şereflişan Vladica Simić Svetlana Sokolova Katharina Stoeckl Jouni Taskinen Amílcar Teixeira Frankie Thielen Teodora Trichkova Simone Varandas Heinrich Vicentini Katarzyna Zajac Tadeusz Zajac Stamatis Zogaris 《Biological reviews of the Cambridge Philosophical Society》2017,92(1):572-607
Freshwater mussels of the Order Unionida provide important ecosystem functions and services, yet many of their populations are in decline. We comprehensively review the status of the 16 currently recognized species in Europe, collating for the first time their life‐history traits, distribution, conservation status, habitat preferences, and main threats in order to suggest future management actions. In northern, central, and eastern Europe, a relatively homogeneous species composition is found in most basins. In southern Europe, despite the lower species richness, spatially restricted species make these basins a high conservation priority. Information on freshwater mussels in Europe is unevenly distributed with considerable differences in data quality and quantity among countries and species. To make conservation more effective in the future, we suggest greater international cooperation using standardized protocols and methods to monitor and manage European freshwater mussel diversity. Such an approach will not only help conserve this vulnerable group but also, through the protection of these important organisms, will offer wider benefits to freshwater ecosystems. 相似文献
165.
Lale Aktay Özgün Sözüer Joshua J. Horns Derviş Kökenek Bilge Kağan Tomas Çağan H. Şekercioğlu 《Zoology in the Middle East.》2017,63(3):189-193
Observation of an unusual population of white-plumaged doves in Osmaniye suggests that these birds are conspecific with the Laughing Dove (Streptopelia senegalensis, Linnaeus, 1766) population in the town. The white-morph is not found outside the urban area. Aside from colouration, the white doves shared identical morphological characteristics with wild-type brown Laughing Doves. Additionally, the white doves and wild-type Laughing Doves formed mixed flocks and readily paired. Based on the observations of four inter-morph pairings, the white morph appears to be a recessive, single autosomal locus mutation. It appears that the white colouration may have originated from one or more hybridization events between Laughing Doves and feral white Barbary Doves (Streptopelia risoria). This study not only identifies an anomalous population of birds in an urban setting, but highlights the importance of traditional knowledge in understanding biodiversity. 相似文献
166.
T. Uysal M. Bozkurt O. Tugay K. Ertuğrul E. N. Şimşek Sezer Y. B. Köse 《Plant biosystems》2017,151(6):949-964
In this paper, 31 mostly endemic and locally distributed Turkish Centaurea taxa belonging to Centaurea and Phalolepis sections were examined in terms of their karyomorphology. The basic chromosome number for all of the studied species was concurringly determined as 9(x = 9) for both sections, excluding C. hierapolitana. We also determined tetraploid and hexaploid species in spite of many species having diploid chromosome numbers. Twelve chromosome counts are reported for the first time and most of the karyotyping analyses are described for the first time via the KAMERAM program. The karyotypes had a predominance of metacentric (m) chromosomes. However, in the karyotyping of six taxa, submetacentric (sm) chromosomes were dominant. Five quantitative asymmetric indices were used to evaluate karyological features of the species. A meaningful dendrogram was carried out to assess the karyotype-symmetry conditions and describe the karyotyping relationships between different taxa. 相似文献
167.
Effects of thermal stratification and mixing on reservoir water quality 总被引:10,自引:0,他引:10
Şebnem Elçi 《Limnology》2008,9(2):135-142
In this study, the effect of thermal stratification on water quality in a reservoir has been investigated by field observations
and statistical analysis. During the summer period, when stratification is evident, field observations indicate that the observed
dissolved oxygen concentrations drop well below the standard limit of 5 mg l−1 at the thermocline, leading to the development of anoxia. The reasons for variations in the dissolved oxygen concentrations
were investigated. Variations of air temperature and other meteorological factors and lateral flows from side arms of the
lake were found to be responsible for the increase of dissolved oxygen concentrations. It was also observed that turbidity
peaked mostly in the thermocline region, closely related to the location of the maximum density gradient and thus low turbulence
stabilizing the sediments in the vertical water column. Relatively cold sediment-laden water flowing into the lake after rain
events also resulted in increased turbidity at the bottom of the lake. Nondimensional analysis widely used in the literature
was used to identify the strength of the stratification, but this analysis alone was found insufficient to describe the evolution
of dissolved oxygen and turbidity in the water column. Thus correlation of these parameters was investigated by multivariate
analysis. Fall (partial mixing), summer (no mixing), and winter (well mixed) models describe the correlation structures between
the independent variables (meteorological parameters) and the dependent variables (water-quality parameters). Statistical
analysis results indicate that air temperature, one day lagged wind speed, and low humidity affected variation of water-quality
parameters. 相似文献
168.
Recently, there has been a resurgence of interest in bioorganic fertilizers as part of sustainable agricultural practices to alleviate drawbacks of intensive farming practices. N2-fixing and P-solubilizing bacteria are important in plant nutrition increasing N and P uptake by the plants, and playing a significant role as plant growth-promoting rhizobacteria in the biofertilization of crops. A study was conducted in order to investigate the effects of two N2-fixing (OSU-140 and OSU-142) and a strain of P-solubilizing bacteria (M-13) in single, dual and three strains combinations on sugar beet and barley yields under field conditions in 2001 and 2002. The treatments included: (1) Control (no inoculation and fertilizer), (2) Bacillus OSU-140, (3) Bacillus OSU-142, (4) Bacillus M-13, (5) OSU-140 + OSU-142, (6) OSU-140 + M-13, (7) OSU-142 + M-13, (8) OSU-140 + OSU-142 + M-13, (9) N, (10) NP. N and NP plots were fertilized with 120 kg N ha–1 and 120 kg N ha–1 + 90 kg P ha- for sugar beet and 80 kg N ha–1 and 80 kg N ha–1 + 60 kg P ha–1 for barley. The experiments were conducted in a randomized block design with five replicates. All inoculations and fertilizer applications significantly increased leaf, root and sugar yield of sugar beet and grain and biomass yields of barley over the control. Single inoculations with N2-fixing bacteria increased sugar beet root and barley yields by 5.6–11.0% depending on the species while P-solubilizing bacteria alone gave yield increases by 5.5–7.5% compared to control. Dual inoculation and mixture of three bacteria gave increases by 7.7–12.7% over control as compared with 20.7–25.9% yield increases by NP application. Mixture of all three strains, dual inoculation of N2-fixing OSU-142 and P-solubilizing M-13, and/or dual inoculation N2-fixing bacteria significantly increased root and sugar yields of sugar beet, compared with single inoculations with OSU-140 or M-13. Dual inoculation of N2-fixing Bacillus OSU-140 and OSU-142, and/or mixed inoculations with three bacteria significantly increased grain yield of barley compared with single inoculations of OSU-142 and M-13. In contrast with other combinations, dual inoculation of N2-fixing OSU-140 and P-solubilizing M-13 did not always significantly increase leaf, root and sugar yield of sugar beet, grain and biomass yield of barley compared to single applications both with N2-fixing bacteria. The beneficial effects of the bacteria on plant growth varied significantly depending on environmental conditions, bacterial strains, and plant and soil conditions. 相似文献
169.
Şule Eryiğit Ali Gelir Esranur Budak Caner Ünlü Azize Gömleksiz İbrahim Özçeşmeci Ahmet Gül 《Luminescence》2022,37(2):268-277
Quantum dots (QDs) are significant fluorescent materials for energy transfer studies with phthalocyanines (Pcs) and phthalocyanine (Pc)-like biomolecules (such as chlorophylls). Carbon-based QDs, especially, have been used in numerous studies concerning energy transfer with chlorophylls, but the numbers of studies concerning energy transfer between phthalocyanines and carbon-based QDs are limited. In this study, peripherally, hydroxythioethyl terminal group substituted metal-free phthalocyanine (H2Pc) and zinc phthalocyanine (ZnPc) were noncovalently (electrostatic and/or π–π interaction) attached to carbon QDs containing boron and nitrogen to form QD-Pc nanoconjugates. The QD-Pc conjugates were characterized using different spectroscopic techniques (Fourier transform infrared spectroscopy and transmission electron microscopy). The absorption and fluorescence properties of QD-Pc structures in solution were studied. It was found that the quantum yields of the QDs slightly decreased from 30% to 25% upon doping the QDs with heteroatoms B and N. Förster resonance energy transfer efficiency was calculated as 33% for BCN-QD/ZnPc. For the other conjugates, almost no energy transfer from QDs to Pc cores was observed. It was shown that the energy transfer between QDs to Pc cores was completely different from the energy transfer between QDs and photosynthetic pigments, and therefore we concluded that heteroatom doping in the QD structure and the existence of zinc metal in the phthalocyanine structure is obligatory for an efficient energy transfer. 相似文献
170.
Banu Şenay 《The journal of the Royal Anthropological Institute》2022,28(2):632-650
‘Dealing with ambiguity’ has become a pressing concern in many spheres of contemporary life, often presented as a ‘survival skill’ in an uncertain world. Working with ambiguity also plays a crucial role in the musical pedagogy of the Ottoman-Turkish ney (Sufi reed flute), the playing of which I discuss in this article. Rather than a constraint or deficiency to be resolved, in the context of ney apprenticeship, ambiguity emerges as a desired pedagogical force not only valued but also deliberately amplified. My aim is to show how ambiguity is embraced here as a productive condition that maximizes possibilities for artistic exploration, freedom of discernment, and aesthetic pleasures. 相似文献