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排序方式: 共有1301条查询结果,搜索用时 194 毫秒
91.
92.
T Kaya M Nishizawa T Yasukawa M Nishiguchi T Onouchi T Matsue 《Biotechnology and bioengineering》2001,76(4):391-394
A microbial chip for bioassay was fabricated and its performance was characterized by scanning electrochemical microscopy (SECM). The microbial chip was prepared by spotting a suspension of Escherichia coli on a polystyrene substrate by using a glass capillary pen. The respiration activity of the E. coli spot was imaged with SECM by mapping the oxygen concentration around the spot. The SECM images of the microbial chips clearly showed spots with lower reduction currents, indicating that E. coli in the spots uptake oxygen by respiration. The bactericidal effects of antibiotics (streptomycin and ampicillin) were measured using the E. coli-based microbial chip, and discussed in comparison with the minimum inhibitory concentration (MIC) determined by an agar plate dilution method. 相似文献
93.
The protective effects of melatonin, vitamin E, and selenium alone or in combination were tested against cadmium-induced oxidative
damage in rat testes. A total of 60 male rats were equally divided into five study groups, one of which acted as control receiving
subcutaneous injections of physiological saline. The remaining four groups were treated with subcutaneous injections of cadmium
chloride at a dose of 1 mg/kg weight. The first study group received no treatment. The second group was treated with a combination
of 60 mg/kg vitamin E and 1 mg/kg sodium selenite. Group 3 was treated with 10 mg/kg melatonin, and the fourth group received
a combination of vitamin E, sodium selenite, and melatonin at the doses mentioned above. After 1 month, the animals were killed,
and the testes were excised for histological inspection and determination of tissue malondialdehyde and the activity of superoxide
dismutase. The animals receiving no treatment showed significantly higher malondialdehyde levels and reduced activity of the
enzyme (p < 0.05). Treatment with antioxidants resulted in a significant reduction in malondialdehyde when compared to the nontreated
animals (p < 0.05) and an increase in the superoxide dismutase activity that was almost the same as the controls. The combination of
melatonin, vitamin E, and selenium appears to have the more profound effect against cadmium-induced testicular injury. 相似文献
94.
The present study was carried to evaluate the protective effects of melatonin alone and vitamin E with selenium combination
against high dose cadmium-induced oxidative stress in rats. The control group received subcutanous physiological saline. The
first study group administered cadmium chloride (CdCl2) by subcutaneous injection of dose of 1 mg/kg. The second study group administered cadmium plus vitamin E with selenium (1 mg/kg
sodium selenite with 60 mg/kg vitamin E); the third study group administered cadmium plus 10 mg/kg melatonin (MLT); the fourth
study group administered CdCl2 plus a combination of melatonin in addition to vitamin E and selenium for a month. Determination levels of plasma malondialdehyde
(MDA), glutathione peroxidase (GSH-Px), blood superoxide dismutase (SOD), creatinine alanine transaminase (ALT), aspartate
aminotransferase (AST), alkaline phosphatase (ALP), blood urea nitrogen (BUN), and urea were measured in serum. In only CdCl2 administered group, the MDA, creatinine, ALT, AST, ALP, and urea levels in the serum were significantly higher than the control
group (p < 0.05). Whereas in all other groups, this values were significantly lower than the only CdCl2 administered group (p < 0.05). Erythrocytes GSH-Px, serum SOD activities of only CdCl2 received group were significantly lower than the control group (p < 0.05). In conclusion, vitamin E + Se, melatonin and vitamin E, and Se, in addition to MLT combinations, had protective
effects against high dose cadmium-induced oxidative damage. 相似文献
95.
Florentin Paris Alain Le Hérissé Huseyin Kozlu William Thornton Dean Yilmaz Günay 《Revue de Micropaléontologie》2007,50(1):81
Revision of the lithostratigraphy of Ordovician deposits in southern and southeastern Turkey led to a re-evaluation of the age assignments of formations identified in the subsurface and at outcrop. Previous datings were based on macrofauna (mainly trilobites and graptolites). The present paper focuses exclusively on organic-walled microfossils (chitinozoans and acritarchs), which provide numerous chronostratigraphical improvements, especially in successions barren or poor in macrofossils. Close to 200 samples were collected in the Taurus chain (i.e. from Kemer, Seydisehir, Ovacik, Kozan, to Sariz regions in southern Turkey) and in the Border Folds (Mardin and Hakkari regions), usually regarded as part of the Arabian Plate in palaeogeographical reconstructions. Many samples are productive and yield chitinozoans and/or acritarchs of extremely variable preservation, depending on their geographical and geological location. In the Taurus chain, the material is “coalified” and frequently fragmented whereas, in the Border Folds, maturation of the organic matter is much lower and preservation of the microfossils is good to excellent. Several Ordovician chitinozoan biozones (northern Gondwana zonation) as well as diagnostic acritarch assemblages are identified in southern and southeastern Turkey. These Ordovician formations are assigned here to the new global stages of the Ordovician chronostratigraphical scale. The Seydisehir (upper part), Sobova, and Kilgen Lake (lower part) formations are referred to the Darriwilian. The Kilgen Lake (upper part), Sort Tepe, and Bedinan formations are attributed to the Sandbian and to the Katian, and the Halevikdere Formation (glacio-marine part) is assigned to the Hirnantian. Reworking of Early Ordovician acritarchs is documented in pre-glacial and in glacial Late Ordovician deposits. They indicate that active erosive processes occurred during the Middle and Late Ordovician sedimentation. The organic-walled microfossils recorded in the Ordovician of south and southeastern Turkey belong to the northern Gondwana realm. Interestingly however, some Baltoscandian influences are noted in the Border Folds during Early Late Ordovician. 相似文献
96.
McMahon KD Yilmaz S He S Gall DL Jenkins D Keasling JD 《Applied microbiology and biotechnology》2007,77(1):167-173
The performance of enhanced biological phosphorus removal (EBPR) wastewater treatment processes depends on the presence of
bacteria that accumulate large quantities of polyphosphate. One such group of bacteria has been identified and named Candidatus Accumulibacter phosphatis. Accumulibacter-like bacteria are abundant in many EBPR plants, but not much is known about their
community or population ecology. In this study, we used the polyphosphate kinase gene (ppk1) as a high-resolution genetic marker to study population structure in activated sludge. Ppk1 genes were amplified from samples collected from full-scale wastewater treatment plants of different configurations. Clone
libraries were constructed using primers targeting highly conserved regions of ppk1, to retrieve these genes from activated sludge plants that did, and did not, perform EBPR. Comparative sequence analysis
revealed that ppk1 fragments were retrieved from organisms affiliated with the Accumulibacter cluster from EBPR plants but not from a plant
that did not perform EBPR. A new set of more specific primers was designed and validated to amplify a 1,100 bp ppk1 fragment from Accumulibacter-like bacteria. Our results suggest that the Accumulibacter cluster has finer-scale architecture
than previously revealed by 16S ribosomal RNA-based analyses.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
97.
Lee DW Choo HY Smitley DR Lee SM Shin HK Kaya HK Park CG Park JK 《Journal of economic entomology》2007,100(1):103-109
Japanese beetle traps baited with the Popillia japonica Newman (Coleoptera: Scarabaeidae) pheromone lure and a eugenol feeding attractant were placed at five golf courses in Korea to determine how well they work for detecting activity of a closely related species, Popillia quadriguttata (F.) (Coleoptera: Scarabaeidae), a turf pest in Korea. The traps also were used to determine the time of day and time of year that P. quadriguttata is most active. Nineteen scarab species of 13 genera were attracted to the Japanese beetle traps with P. quadriguttata clearly being the most abundant (383 beetles per trap), followed by Adoretus tenuimaculatus Waterhouse (10 per trap), Popilliaflavosellata Fairmaire (seven per trap), Exomala orientalis Waterhouse (four per trap), and Maladera japonica (two per trap). Other scarab species were trapped at a rate of <1.0 per trap. Popillia quadriguttata adults were active over a 5-wk period in late June and early July. At Yongwon Golf Club in 2002, peak adult activity was during the last week of June in visual counts and approximately 1 wk later in the Japanese beetle traps. In Korea, P. quadriguttata adults are most active between 12:00 p.m. and 4:00 p.m. This information should be helpful to golf course superintendents in Korea and to entomologists interested in finding natural enemies of P. quadriguttata to evaluate as potential biocontrol organisms for the very closely related species, the Japanese beetle. 相似文献
98.
Homozygous mutations in fibroblast growth factor 3 are associated with a new form of syndromic deafness characterized by inner ear agenesis, microtia, and microdontia 下载免费PDF全文
Tekin M Hişmi BO Fitoz S Ozdağ H Cengiz FB Sirmaci A Aslan I Inceoğlu B Yüksel-Konuk EB Yilmaz ST Yasun O Akar N 《American journal of human genetics》2007,80(2):338-344
We identified nine individuals from three unrelated Turkish families with a unique autosomal recessive syndrome characterized by type I microtia, microdontia, and profound congenital deafness associated with a complete absence of inner ear structures (Michel aplasia). We later demonstrated three different homozygous mutations (p.S156P, p.R104X, and p.V206SfsX117) in the fibroblast growth factor 3 (FGF3) gene in affected members of these families, cosegregating with the autosomal recessive transmission as a completely penetrant phenotype. These findings demonstrate the involvement of FGF3 mutations in a human malformation syndrome for the first time and contribute to our understanding of the role this gene plays in embryonic development. Of particular interest is that the development of the inner ear is completely disturbed at a very early stage--or the otic vesicle is not induced at all--in all of the affected individuals who carried two mutant FGF3 alleles. 相似文献
99.
Morimoto H Ozaki A Okamura H Yoshida K Amorim BR Tanaka H Kitamura S Haneji T 《Cell biochemistry and function》2007,25(4):369-375
In the present study, we examined the expression and cytolocalization of protein phosphatase type 1 (PP1) isoforms and nucleolin in human osteoblastic cell line MG63 cells at two boundaries in the cell cycle. We treated MG63 cells with hydroxyurea and nocodazole to arrest the cells at the G(1)/S and G(2)/M boundaries, respectively. As judged from the results of Western blot analysis, PP1 isoforms were expressed differently at each boundary of the cell cycle. Nucleolin was also shown to have a different expression pattern at each boundary. In the hydroxyurea-treated cells, nucleolus-like bodies were bigger in size and decreased in number compared with those in asynchronized cells. However, the subcellular localization of PP1s and nucleolin was not changed. Anti-nucleolin antibody interacted with 110-kDa and 95-kDa proteins present in asynchronized cells and in the cells treated with hydroxyurea. Treatment of the cells with nocodazole decreased the level of the 95-kDa form of nucleolin. In the nocodazole-treated cells, it was impossible to distinguish the distribution of each protein. The phosphorylation status of nucleolin in the cell cycle arrested samples was examined by 2D-IEF-PAGE followed by Western blot analysis. In the case of asynchronized cells or hydroxyurea-treated ones, nucleolin was located at a basic isoelectric point (dephosphorylated status); whereas in the G(2)/M arrest cells, the isoelectric point of nucleolin shifted to an acidic status, indicating that nucleolin was phosphorylated. The present results indicate that PP1 and nucleolin were differently expressed at G(1)/S and G(2)/M boundaries of the cell cycle and acted in a different fashion during cell-cycle progression. 相似文献
100.
Kutlu S Colakoglu N Halifeoglu I Sandal S Seyran AD Aydin M Yilmaz B 《Cell biochemistry and function》2007,25(2):167-172
Polychlorinated biphenyls (PCBs) are persistent environmental pollutants. This study compared effects of two PCB mixtures, Aroclors 1221 (A1221) and 1254 (A1254) on serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, creatinine and uric acid in female rats. Histopathological changes in the liver and kidney were also examined. A group of adult Wistar rats served as controls. Groups II and III were subcutaneously injected with A1221 and A1254 at 10 mg/kg every other day for 6 weeks. At the end of this period, all animals were decapitated and blood samples were collected. Serum urea, creatinine, uric acid, ALT, AST and ALP levels were determined. Liver and kidney were collected for histopathological examination. They were fixed in formaldehyde and processed for light microscopy. Both A1221 and 1254 significantly elevated serum ALT (p < 0.05) and AST (p < 0.01) levels compared to the control group. Serum ALP values were significantly increased by A1221 (p < 0.05), but they were unaffected in the A1254 group. Treatment with both A1221 and A1254 significantly increased serum levels of urea (p < 0.05), creatinine (p < 0.01) and uric acid (except in the A1221 group; p < 0.005). Distinct histopathological changes including renal corpuscular atrophy, peritubular vascular congestion and dilated cortical tubules, sinusoidal dilatation, congestion and mononuclear cell infiltration were observed. These findings suggest that PCBs may cause nephrotoxicity and hepatotoxicity in female rats. 相似文献