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1.
Emine Alçitepe 《Biologia》2008,63(3):338-342
The morphological, anatomical and palynological features of Asyneuma michauxioides (Boiss.) Damboldt (Campanulaceae) were investigated. This species is an East Mediterranean Floristic Element and an endemic in Turkey. In anatomical studies, cross-sections of the root and stem were examined and demonstrated by photographs. It has conspicuous endodermis in which the Casparian bands are indistinct in the stem. According to the result of this study, it was found that pollen grain of this taxon was 3-porate sometimes 4-porate and oblate-spheroidal. Its structure was tectate and sculpture was small granules and pits with densely spaced spinules. The seeds of the taxon were eliptic to ovate in shape, laterally compressed, brown to light brown in colour, glabrous and shiny.  相似文献   
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Biosurfactant production by Pseudomonas aeruginosa EBN-8 mutant was studied in shake flasks on separate wastes from canola, soybean and corn oil refineries. Of the substrates tested, canola oil refinery waste (COD=20 g l−1) supplemented with sodium nitrate (at COD/N=20) showed the best microbial growth (4.50 g l−1) and rhamnolipid production (8.50 g l−1), at 10 d of incubation with the specific growth rate of 0.316 h−1 and specific product yield of 0.597 g g−1 h. Its cell-free supernatant showed the critical micelle dilution (CMD) of 150 and surface tension (ST) of 28.5 mN m−1.  相似文献   
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Caffeic acid phenethyl ester (CAPE) is a natural product with potent anti-inflammatory, antitumor, and antioxidant activities, and attenuates inflammation and lipid peroxidation. The purpose of the present study was to investigate the effects of CAPE on iron-induced liver damage. Rats were divided into four groups and treated for 7 days with saline (control group), 10 μmol kg CAPE/day s.c. (CAPE group), 50 mg iron-dextran/kg i.p. (IRON group) and CAPE and iron at the same time (IRON+CAPE group). Seven days later, rats were killed and the livers were excised for biochemical analysis. The administration of IRON alone resulted in higher myeloperoxidase (MPO) activity and lipid peroxidation than in the control and CAPE treatment prevented the increase in MPO activity and malondialdeyde (MDA) level. No differences were observed in all four groups with regards to superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities. Our results collectively suggest that CAPE may be an available agent to protect the liver from injury via inhibition of MPO activity.  相似文献   
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It is believed that some wastes play an important role on the pollution prevention. In this paper, three different natural biomasses were investigated as biosorbent. Salsola green plant which grown at Jubail (industrial area) in KSA, it is phyto remediation plant. Salsola is metal hyper accumulation plant, it adsorbed (23.5, 25.7 mg lead per gram stem or leaf) from soil. Also it can be reused as ion exchanger for pb2+ from solution. Shrimp shell’s used for extraction of chitosan in laboratory with degree of substitution 81%. Chitosan and crosslinked carboxymethyl chitosan were investigated for pb2+ adsorption and compared with crosslinked carboxymethyl corn cob. The adsorption experiments demonstrated that the three biomasses have high adsorption capacity for pb2+, good reusability and stability for three cycles.  相似文献   
9.
Campylobacter jejuni is the leading cause of human bacterial gastroenteritis worldwide, but source attribution of the organism is difficult. Previously, DNA microarrays were used to investigate isolate source, which suggested a non‐livestock source of infection. In this study we analysed the genome content of 162 clinical, livestock and water and wildlife (WW) associated isolates combined with the previous study. Isolates were grouped by genotypes into nine clusters (C1 to C9). Multilocus sequence typing (MLST) data demonstrated that livestock associated clonal complexes dominated clusters C1–C6. The majority of WW isolates were present in the C9 cluster. Analysis of previously reported genomic variable regions demonstrated that these regions were linked to specific clusters. Two novel variable regions were identified. A six gene multiplex PCR (mPCR) assay, designed to effectively differentiated strains into clusters, was validated with 30 isolates. A further five WW isolates were tested by mPCR and were assigned to the C7‐C9 group of clusters. The predictive mPCR test could be used to indicate if a clinical case has come from domesticated or WW sources. Our findings provide further evidence that WW C. jejuni subtypes show niche adaptation and may be important in causing human infection.  相似文献   
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The results of studying the precedence effect in the case where the direct and delayed (reflected) signals are located in the vertical and horizontal planes are considered. Loudspeakers emitting direct and reflected sounds were placed 45 deg to the left and right of the median line of the subject’s head in the horizontal plane and in front of and above the subject’s head, i.e., with 0 and 90 deg of elevation relative to the eye level, in the vertical plane. It has been shown that the time limits of the precedence effect of short (5-ms) signals are similar in the horizontal and vertical planes. For signals more than 10 ms in duration, the values of echo thresholds were higher in the vertical plane and significantly differed (p < 0.05) from the thresholds in the horizontal plane.  相似文献   
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