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61.
BK Clapperton TD Day DKJ Morgan F Huddart N Cox LR Matthews 《New Zealand journal of zoology.》2013,40(2):104-118
Repellents used to reduce by-kill of birds during pest control must not compromise acceptance by target species. Two repellents combined, anthraquinone (AQ; 0.4 g kg?1) and d-pulegone (DP; 1.0) did not reduce the palatability of blue-coloured carrot baits to laboratory rats (Rattus norvegicus); nor did DP (2.0). Green-coloured carrot baits coated with AQ, DP or AQ + DP were taken from bait stations by wild possums (Trichosurus vulpecula) and rats. Toxic (1080) bait coated with AQ (0.4) and peanut oil (0.1) had reduced palatability but was accepted by laboratory rats. However, laboratory rats did not consume enough baits coated with AQ and bacon, peanut butter, cinnamon or DP to be killed. Anthraquinone (0.4 or 0.8) plus cinnamon and DP (0.5) did not affect palatability or lethality to captive ship rats (R. rattus) or possums. Anthraquinone and DP as surface coatings on baits are therefore acceptable to possums and possibly rats, at concentrations that deter some bird species. 相似文献
62.
Seifan Mostafa Sarmah Ajit K. Ebrahiminezhad Alireza Ghasemi Younes Samani Ali Khajeh Berenjian Aydin 《Applied microbiology and biotechnology》2018,102(5):2167-2178
Applied Microbiology and Biotechnology - Immobilization has been reported as an efficient technique to address the bacterial vulnerability for application in bio self-healing concrete. In... 相似文献
63.
Alireza Ebrahiminezhad Alireza Zare-Hoseinabadi Ajit K. Sarmah Saeed Taghizadeh Younes Ghasemi Aydin Berenjian 《Molecular biotechnology》2018,60(2):154-168
Nanoscale iron particles have attracted substantial interest due to their unique physical and chemical properties. Over the years, various physical and chemical methods have been developed to synthesize these nanostructures which are usually expensive and potentially harmful to human health and the environment. Synthesis of iron nanoparticles (INPs) by using plant extract is now of great interest in order to develop a novel and sustainable approach toward green chemistry. In this method the chemical compounds and organic solvents are replaced with phytochemicals and aqueous matrixes, respectively. Similar to any chemical and biochemical reaction, factors such as reaction temperature, concentration of iron precursor, concentration of leaf extract, and reaction time have critical effects on the reaction yield. This review focuses on the novel approaches used for green synthesis of INPs by using plant resources. The currently available statistics including the factors affecting the synthesis process and potential applications of the fabricated nanoparticles are discussed. Recommendations are also given for areas of future research in order to improve the production process. 相似文献
64.
Choline acetyltransferase activity of spinal cord cell cultures increased by co-culture with muscle and by muscle-conditioned medium 总被引:6,自引:3,他引:6 下载免费PDF全文
Activity of the enzyme choline acetyltransferase (CAT), which mediates the synthesis of the neurotransmitter, acetylcholine, was increased up to 20- fold in spinal cord (SC) cells grown in culture with muscle cells for 2 wk. This increase was directly related to the duration of co-culture as well as to the cell density of both the SC and muscle involved and was not affected by the presence of the acetylcholine receptor blocking agent, α-bungarotoxin. Glutamic acid decarboxylase (GAD) activity was often markedly decreased in SC-muscle cultures while the activities of acetylcholinesterase and several other enzymes were little changed. Increased CAT activity was also observed when SC cultures were maintained in medium which had been conditioned by muscle cells or by undifferentiated cells from embryonic muscle. Muscle-conditioned medium (CM) did not affect the activities of SC cell GAD or acetylcholinesterase. Dilution or concentration of the CM directly affected its ability to increase SC CAT activity , as did the duration and timing of exposure of the SC cells to the CM. The medium could be conditioned by muscle cells in the presence or absence of serum, and remained effective after dialysis or heating to 58 degrees C. Membrane filtration data were consistent with the conclusion that the active material(s) in CM had a molecular weight in excess of 50,000 daltons. We conclude that large molecular weight material that is released by muscle cells is capable of producing a specific increase in CAT activity of SC cells. 相似文献
65.
Pierre Antony Kristen Hoek Bhaskarjyoti Sarmah Wasif N. Khan 《Biological procedures online》2007,9(1):73-83
B cell subpopulations in the spleen have been extensively characterized phenotypically; however, biochemical properties of
these cell populations following B cell antigen receptor engagement have not been fully determined due to technical difficulties
and limiting cell numbers. We therefore employed mini-scale protocols to assess lipid signaling, particularly that of diacylglycerol
and inositol trisphosphate, with as few as 0.5×106 purified early (T1) and late (T2) transitional B cells. Additionally, utilizing flow cytometric techniques, we determined
levels of phosphatidylinositol bisphosphate and calcium mobilization in T1 and T2 cells, as well as mature follicular and
marginal zone B cells using less than 1×106 primary B cells. Thus, these biochemical and flow cytometric methodologies can be used to analyse signal-induced changes
in phosphatidylinositol bisphosphate levels, diacylglycerol and inositol triphosphate production and calcium in each B cell
population.
These authors contributed equally. 相似文献
66.
Interactions between bovine γ-globulin (BGG) and borohydride-capped silver nanoparticles (BAgNPs) were studied using dynamic light scattering (DLS) and spectroscopic techniques such as UV–vis spectroscopy, fluorescence, and circular dichroism. The results were compared with earlier reported interactions between γ-globulin and citrate-coated AgNPs (CAgNPs). BAgNPs were synthesized and characterized. Irrespective of the coating on AgNPs, nanoparticles had formed ground-state complexes with the protein. CAgNPs, as well as BAgNPs had caused static quenching of tryptophan (Trp) fluorescence of the protein. The change in the capping agent from citrate to borohydride weakened the binding of nanoparticles with the protein. But the same change in capping agent had increased the fluorescence quenching efficiency of AgNPs. Hydrogen bonding and van der Waals interactions were involved in BGG–BAgNPs complex similar to the CAgNPs complex with γ-globulin. Polarity of the Trp microenvironment in BGG was not altered using BAgNPs as opposed to CAgNPs, as supported using synchronous and three-dimensional fluorescence. Resonance light scattering experiments also suggested nano-bio conjugation. Far-UV and near-UV circular dichroism (CD) spectra respectively pointed towards changes in the secondary and tertiary structure of BGG by BAgNPs, which was not observed for CAgNPs. 相似文献
67.
Spermatozoal and seminal plasma concentrations of total lipids from 50 ejaculates and phospholipids and their fractions from 30 ejaculates were quantified in the semen of five Murrah buffalo bulls. Sperm lipid content ranged from 0.93 to 1.72 mg/10(9) cells with an overall average 1.32 +/- 0.03 mg/10(9) cells. Its concentration in seminal plasma varied from 1.39 to 2.22 mg/ml with overall average of 1.75 +/- 0.03 mg/ml. Spermatozoal total phospholipid content ranged from 0.44 to 0.94 mg/10(9) cells with overall mean being 0.64 +/- 0.02 mg/10(9) cells. The corresponding values for seminal plasma were 0.53 and 0.88 mg/ml with an overall mean of 0.69 +/- 0.02 mg/ml. Phosphatidyl choline constituted the major fraction both in the spermatozoa and and seminal plasma. 相似文献
68.
G M Garrity BK Heimbuch M Gagliardi 《Journal of industrial microbiology & biotechnology》1996,17(3-4):260-267
We have undertaken a study to estimate the species diversity of zoosporogenous actinomycetes that can be isolated from an arid environment. The study site encompassed an area of approximately 22 000 square kilometers of the Mojave Desert along the California-Nevada border. A series of 29 soil samples was collected along two intersecting transects of approximately 190 and 240 km which traversed a number of distinct ecosystems. A0 horizon soils were collected from the rhizosphere of the predominant vegetation at each sampling site and screened for the target genera using selective isolation techniques: chemoattraction (xylose and -collidine) and baiting with hair. Following incubation of primary isolation plates for 28 days at 28°C, all colonies that exhibited filamentous growth, presence of sporangia and/or motile spores upon direct microscopic observation (450 and 1000×) were further characterized by fatty acid analysis (FAME). Most of the isolates fell into three broad clusters that roughly correlated with presumptive genus assignments. Individual isolates could be assigned to 226 FAME biotypes based on chromatographic similarity (85%). The dominant species (514/826 isolates) belong to a previously undescribed taxon that morphologically resemblesGeodermatophilus but possesses unique FAME profiles that include at least three novel lipids. The remainder of the isolates were species ofActinoplanes, indeterminate species or vagrant isolates ofStreptomyces. 相似文献
69.
N P Sarmah K Sarma D R Bhattacharyya A A Sultan D Bansal N Singh P K Bharti R Sehgal P K Mohapatra P Parida J Mahanta 《Journal of biosciences》2017,42(4):531-535
Malaria is a major public health concern in Northeast India with a preponderance of drug-resistant strains. Until recently the partner drug for artemisinin combination therapy (ACT) was sulphadoxine pyrimethamine (SP). Antifolate drug resistance has been associated with the mutations at dihydropteroate synthase (dhps) and dihydrofolatereductase (dhfr) genes. This study investigated antifolate drug resistance at the molecular level. A total of 249 fever cases from Arunachal Pradesh, NE India, were screened for malaria, and of these, 75 were found to be positive for Plasmodium falciparum. Samples were sequenced and analysed with the help of BioEdit and ClustalW. Three novel point mutations were found in the dhps gene with 10 haplotypes along with the already reported mutations. A single haplotype having quadruple mutation was found in the dhfr gene. The study reports higher degree of antifolate drug resistance as evidenced by the presence of multiple point mutations in dhps and dhfr genes. The findings of this study strongly discourage the use SP as a partner drug in ACT. 相似文献
70.
Ornithogenic soils that form in penguin rookeries contain high levels of organic carbon and nitrogen. On Seabee Hook, Cape
Hallett, Antartica, ornithogenic soil was contaminated with hydrocarbons following establishment of a scientific research
station. In these soils hydrocarbon biodegradation could be supported by available soil nitrogen. Hexadecane mineralization
activity was detected in vitro in ornithogenic soil when incubated at 5 or 15°C. At 5°C the extent of hexadecane mineralization
was higher in hydrocarbon-contaminated soil than in uncontaminated soil. Alkane-degrading bacteria isolated from Seabee Hook
soil were identified as Rhodococcus or Gordonia spp. or an unclassified Corynebacterineae. The alkane degraders grew on n-alkanes from heptane (C8) to eicosane (C20) and pristane, and utilized uric acid or ammonium nitrate as nitrogen source.
All of the isolates possessed urease activity. Results of this study indicate biodegradation of hydrocarbons may contribute
to the natural attenuation of oil spills in ornithogenic surface soils in summer. 相似文献