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排序方式: 共有582条查询结果,搜索用时 15 毫秒
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Zübeyde Filiz Arslan 《Biodiversity and Conservation》2018,27(12):3267-3286
Wheat is widely grown in Turkey in the winter season, generally and weeds have been problem in production. Changes in agricultural practices such as increasing mechanization, changing cropping systems and widely use of herbicides and fertilizers has been causing some changes in weed flora in wheat fields from past to present. A contemporary weed survey was done in 2014 in the wheat fields of ?anl?urfa province, which dominate the production of Southeastern region and results were compared with a former survey done in 1967 in the same region. As a result of the comparison, flora has been notably changed; the number of weed species declined from 221 to 71 which means more than threefold diversity loss. In addition, species common over 50% of fields declined dramatically and some foremost species in the past were not recorded contemporary studies whereas some are recorded later. General density of weeds slightly increased in time with a volunteer crop (lentil) in 2014, however, without volunteer crop, the density also declined by about half. Similarly, the density and frequency of dominant species decreased markedly from past to present except some exceptions. The most important reasons for this change are increased use of herbicides and the change of the regional alternation system. It should be noted that biodiversity loss is lower than comparing to the developed world and there is a chance to conserve this through employing sustainable methods. Furthermore, problems related to weed identification were discussed using data from these surveys. 相似文献
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Sohel Md Mahmodul Hasan Akyuz Bilal Konca Yusuf Arslan Korhan Gurbulak Kutlay Abay Murat Kaliber Mahmut Cinar Mehmet Ulas 《Mammalian genome》2020,31(9-12):309-324
Mammalian Genome - Maternal nutrition during pregnancy is one of the major intrauterine environmental factors that influence fetal development by significantly altering the expression of genes that... 相似文献
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Hacer Tugba Degirmencioglu Etil Guzelmeric Parla Isil Yuksel Hasan Krmzbekmez Inci Deniz Erdem Yesilada 《化学与生物多样性》2019,16(12)
This study was undertaken to analyze the phenolic profiles of 19 propolis samples from Turkey by using a high‐performance thin‐layer chromatographic (HPTLC) method in order to identify their plant origins. Furthermore, their antioxidant and antimicrobial activity profiles were comparatively evaluated. For the appraisal of antioxidant potential, total phenolic (TPC) and total flavonoid contents (TFC) of propolis samples were firstly determined and then their effects on free radicals were evaluated by FRAP, ABTS.+, CUPRAC, DPPH. and HPTLC‐DPPH. methods. Antimicrobial activity of propolis samples against Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 11229) and Candida albicans ATCC 10231 were determined by disc diffusion and broth dilution methods. HPTLC fingerprinting analyses revealed that O‐type (botanical origin from Populus nigra L.) was the primarily available propolis type in Turkey. Moreover, 3‐O‐methylquercetin (3MQ) rich propolis was identified as a new propolis type for the first time. Principal component analysis (PCA) indicated that 3MQ‐type propolis differs from the O‐type. Antioxidant activity studies showed that O‐type of propolis possesses higher antioxidant effect than the other tested propolis types. Quercetin, caffeic acid, caffeic acid phenethyl ester (CAPE) and galangin were determined to contribute significantly to the antioxidant potential of O‐type propolis among others. Propolis extracts exerted moderate antimicrobial activity against the tested microorganisms with MIC values between the ranges of 128–512 μg/mL. 相似文献
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Hamna Saleem Muhammad Arslan Khadeeja Rehman Razia Tahseen Muhammad Afzal 《Saudi Journal of Biological Sciences》2019,26(6):1179-1186
Helophytic plants contribute significantly in phytoremediation of a variety of pollutants due to their physiological or biochemical mechanisms. Phenol, which is reported to have negative/deleterious effects on plant metabolism at concentrations higher than 500 mg/L, remains hard to be removed from the environmental compartments using conventional phytoremediation procedures. The present study aims to investigate the feasibility of using P. australis (a helophytic grass) in combination with three bacterial strains namely Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, in a floating treatment wetland (FTW) for the removal of phenol from contaminated water. The strains were screened based on their phenol degrading and plant growth promoting activities. We found that inoculated bacteria were able to colonize in the roots and shoots of P. australis, suggesting their potential role in the successful removal of phenol from the contaminated water. Pseudomonas sp. LCRH90 dominated the bacterial community structure followed by A. lowfii ACRH76 and B. cereus LORH97. The removal rate was significantly high when compared with the individual partners, i.e., plants and bacteria separately. The plant biomass, which was drastically reduced in the presence of phenol, recovered significantly with the inoculation of bacterial consortia. Likewise, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total organic carbon (TOC) is achieved when both plants and bacteria were employed. The study, therefore, suggests that P. australis in combination with efficient bacteria can be a suitable choice to FTWs for phenol-degradation in water. 相似文献
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Netherlands Heart Journal - Data on the impact of the cumulative percutaneous left atrial appendage closure (LAAC) caseload on cardiovascular outpatient and hospitalisation costs are limited. The... 相似文献
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Fatih Arslan Joo Y. Hong Vydehi Kanneganti Sei-Kyoung Park Susan W. Liebman 《PLoS genetics》2015,11(1)
Prions are self-perpetuating conformational variants of particular proteins. In yeast, prions cause heritable phenotypic traits. Most known yeast prions contain a glutamine (Q)/asparagine (N)-rich region in their prion domains. [PSI+], the prion form of Sup35, appears de novo at dramatically enhanced rates following transient overproduction of Sup35 in the presence of [PIN+], the prion form of Rnq1. Here, we establish the temporal de novo appearance of Sup35 aggregates during such overexpression in relation to other cellular proteins. Fluorescently-labeled Sup35 initially forms one or a few dots when overexpressed in [PIN+] cells. One of the dots is perivacuolar, colocalizes with the aggregated Rnq1 dot and grows into peripheral rings/lines, some of which also colocalize with Rnq1. Sup35 dots that are not near the vacuole do not always colocalize with Rnq1 and disappear by the time rings start to grow. Bimolecular fluorescence complementation failed to detect any interaction between Sup35-VN and Rnq1-VC in [PSI
+][PIN
+] cells. In contrast, all Sup35 aggregates, whether newly induced or in established [PSI
+], completely colocalize with the molecular chaperones Hsp104, Sis1, Ssa1 and eukaryotic release factor Sup45. In the absence of [PIN+], overexpressed aggregating proteins such as the Q/N-rich Pin4C or the non-Q/N-rich Mod5 can also promote the de novo appearance of [PSI
+]. Similar to Rnq1, overexpressed Pin4C transiently colocalizes with newly appearing Sup35 aggregates. However, no interaction was detected between Mod5 and Sup35 during [PSI+] induction in the absence of [PIN
+]. While the colocalization of Sup35 and aggregates of Rnq1 or Pin4C are consistent with the model that the heterologous aggregates cross-seed the de novo appearance of [PSI
+], the lack of interaction between Mod5 and Sup35 leaves open the possibility of other mechanisms. We also show that Hsp104 is required in the de novo appearance of [PSI+] aggregates in a [PIN
+]-independent pathway. 相似文献