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In Vitro Cellular & Developmental Biology - Plant - The OsRGLP1 gene was overexpressed under the control of CaMV 35S promoter in tomato (Solanum lycopersicum L.) plants using...  相似文献   
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A total of 318 Campylobacter strains from sporadic cases of human enteritis (109 strains) and healthy slaughterhouse animals in northern Germany (209 strains) were bio- and serotyped according to the Lior typing schemes. Three hundred strains were typable (94.3%) and 38 serovars were identified. Among human strains 28 serovars were identified with 30% of them belonging to serovar 4. Strains from pigs were associated with 25 serovars, the most frequent being serovar 20 (21.2%). Fourteen serovars were identified in the ovine strains of which 31.1% were of serovar 49, and 22.2% of serovar 4. All of the strains from one chicken farm were of serovar 11, whereas in those from another serovar 1 was predominant (85.4%). Twenty-five of the 38 serovars identified were associated with at least two different biovars. Campylobacter jejuni biovar I was predominant in humans, sheep and chickens and Campylobacter coli biovar I in pigs. The results suggest that the combined use of bio- and serotyping according to the Lior typing schemes would be of use in studies on the epidemiology of human campylobacteriosis in Germany.  相似文献   
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The Kosi coastal lake system, a chain of four interconnected basins, is located in the subtropical north-eastern corner of South Africa. Little information is available on zooplankton of the system and the main aim of this study is to report on zooplankton samples collected during 2002 and 2003. The set of samples consists of seasonal, subsurface mesozooplankton samples that were collected during nighttime in each of the lakes. A well-developed salinity gradient was evident along the interconnected lakes in the subsurface water during all seasons, ranging from freshwater in the upper lake Amanzamnyama to a maximum of 22 recorded in Lake Makhawulani. The zooplankton community structures of the lakes reflected the salinity gradient of the system, with some coastal marine taxa recorded in the lakes closer to the mouth and only freshwater taxa recorded in Lake Amanzamnyama. Mesozooplankton diversity and abundance were relatively low compared to other estuarine systems along the eastern coast of South Africa. The dominant taxa were calanoid copepods Acartiella natalensis and Pseudodiaptomus stuhlmanni and the mysid Mesopodopsis africana in the lower lakes, whereas cyclopoids Mesocyclops sp. and Thermocyclops sp. dominated the freshwater lake Amanzamnyama.  相似文献   
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The effects of cadmium stress (0, 25, 50, 75, and 100 mg/L) on morpho-physiological features and selected genes (carotenoid hydroxilase, amidase, GR, bHLH, NRAMP and YSL) expression were demonstrated in Arundo donax L. The plants were assessed for Cd uptake and its effects on chlorophyll and antioxidants after 30 days of exposure. The expression of genes conferring metal tolerance was evaluated after 10 days of Cd exposure. The results showed a maximum Cd uptake in roots (872 mg/kg) followed by stem (734 mg/kg) and leaves (298 mg/kg) at highest supplied Cd concentration. The Cd uptake reduced dry weight, Chla, Chlb, and total Chl contents of giant reed. The SOD, CAT, POD activities and MDA content increased at the maximum Cd concentration over control. The highest genes expression for carotenoid hydroxylase, glutathione reductase and amidase was observed in plants exposed to 100 mg/L. However, differential bHLH gene expression and slightly increased gene expression of NRAMP was noted for different Cd treatments. Amidase expressed under Cd stress which is pioneer report in A. donax. These results provided insights into the mechanisms of A. donax tolerance and survival under Cd Stress.  相似文献   
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Wastewater treatment based on ecological principles is a low cost and highly desirable solution for the developing countries like Pakistan. The present study evaluated the effectiveness of biological treatment systems including Internal Circulation (IC) anaerobic bioreactor and constructed wetlands (CWs) containing macrophytes and mixed algal cultures for industrial wastewater treatment. The IC bioreactor reduced COD (52%), turbidity (89%), EC (24%) of the industrial wastewater. However, the effluents of IC bioreactor did not comply with National Environmental Quality Standards (NEQS) of Pakistan. Post-treatment of IC bioreactor effluents was accomplished in CW containing macrophytes (Arundo donax and Eichhornia crassipes) and mixed algal culture. The CWs planted with macrophytes lowered the concentrations of COD (89%) and turbidity (99%). CWs with algal biomass were not effective in further polishing the effluent. Inhibition of algal biomass growth was observed due to physicochemical characteristics of wastewater. The integrated treatment system consisting of IC bioreactor and macrophytes was found more suitable option for industrial wastewater treatment.  相似文献   
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In recent years, NO, a gas previously considered a potentially toxic chemical, has become established as a diffusible universal messenger mediating cell—cell communication throughout the body. In mammals, NO is a recognized mediator of blood vessel relaxation that helps to maintain blood pressure. In the central nervous system NO acts as a non-conventional neurotransmitter and participates in the establishment of long-term plasticity required for memory formation. In addition, NO is responsible for some parts of the host response to sepsis and inflammation and contributes to certain disease states. A number of strategies have emerged with regard to a pharmacological control of pathological NO overproductions. This review will discuss these novel therapeutic approaches that may provide new means for clinical medicine.  相似文献   
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