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991.
Roberto Lomba Nicastro Mário Eidi Sato Marcos Zatti Da Silva 《Experimental & applied acarology》2010,50(3):231-241
Studies on artificial laboratory selections with milbemectin, stability of milbemectin resistance and possible cross-resistance with abamectin were carried out with Tetranychus urticae Koch to provide basic information for a milbemectin resistance management program. Selections for resistance and susceptibility to milbemectin were performed in a population of T. urticae, collected from a commercial chrysanthemum field in the State of São Paulo, Brazil. After six selections for resistance and five selections for susceptibility, susceptible (S) and resistant (R) strains of T. urticae to milbemectin were obtained. The resistance ratio (R/S) at the LC50 reached 409-fold value. The stability of milbemectin resistance was also studied under laboratory conditions, using a population with initial frequency of 75% of resistant mites. The frequencies of milbemectin resistance were evaluated monthly for a period of 7 months. In order to observe possible correlation between milbemectin and abamectin resistance, the frequencies of abamectin resistance were also evaluated for that population, during the same period. The frequency of milbemectin resistance decreased from 75 to 14.5%, while the percentage of abamectin resistant mites decreased from 57 to 9.1%, in 7 months. The frequencies of milbemectin and abamectin resistance were also evaluated in 25 field populations of T. urticae, collected from several crops in the State of São Paulo. The frequencies of milbemectin resistance varied from 4.1 to 89.5%, and of abamectin, from 7.0 to 90.5%. A positive and significant correlation was observed between the frequencies of milbemectin and abamectin resistance, indicating positive cross-resistance between these acaricides. The results indicate that abamectin should be avoided for managing milbemectin resistance in T. urticae. This is the first report on milbemectin resistance in T. urticae in Brazil. 相似文献
992.
The function of GABA in the adrenal medulla is still controversial. We will review experimental results in vivo and in vitro
in adrenal chromaffin cells of various mammals to clarify what has been elucidated and what still remains to be settled. 相似文献
993.
Selvaraj Michael Gomez N. Manikanda Boopathi S. Satheesh Kumar T. Ramasubramanian Zhu Chengsong P. Jeyaprakash A. Senthil R. Chandra Babu 《Acta Physiologiae Plantarum》2010,32(2):355-364
Drought is a major limitation for rice production in rainfed ecosystems. Identifying quantitative trait loci (QTLs) linked
to drought resistance provides opportunity to breed high yielding rice varieties suitable for drought-prone areas. Although
considerable efforts were made in mapping QTLs associated with drought-resistance traits in rice, most of the studies involved
indica × japonica crosses and hence, the drought-resistance alleles were contributed mostly by japonica ecotypes. It is desirable to look for genetic variation within indica ecotypes adapted to target environment (TE) as the alleles from japonica ecotype may not be expressed under lowland conditions. A subset of 250 recombinant inbred lines (RILs) of F8 generation derived from two indica rice lines (IR20 and Nootripathu) with contrasting drought-resistance traits were used to map the QTLs for morpho-physiological
and plant production traits under drought stress in the field in TE. A genetic linkage map was constructed using 101 polymorphic
PCR-based markers distributed over the 12 chromosomes covering a total length of 1,529 cM in 17 linkage groups with an average
distance of 15.1 cM. Composite interval mapping analysis identified 22 QTLs, which individually explained 4.8–32.2% of the
phenotypic variation. Consistent QTLs for drought-resistance traits were detected using locally adapted indica ecotypes, which may be useful for rainfed rice improvement. 相似文献
994.
Martin Rudwaleit Filip Van den Bosch Martina Kron Sonja Kary Hartmut Kupper 《Arthritis research & therapy》2010,12(3):R117
Introduction
Tumor necrosis factor (TNF) antagonists reduce the signs and symptoms of spondyloarthritides, including ankylosing spondylitis (AS) and psoriatic arthritis (PsA). Our objective was to evaluate the effectiveness and safety of adalimumab, 40 mg every other week, for patients with AS or PsA and prior treatment with infliximab (IFX) and/or etanercept (ETN). 相似文献995.
Study of the factors affecting the extraction of soybean protein by reverse micelles 总被引:3,自引:0,他引:3
Xihong Zhao Yanmei Li Xiaowei He Nanjing Zhong Zhenbo Xu Liansheng Yang 《Molecular biology reports》2010,37(2):669-675
In this work, the forward and back extraction of soybean protein by reverse micelles was studied. The reverse micellar systems
were formed by anionic surfactant sodium bis(2-ethyl hexyl) sulfosuccinate (AOT), isooctane and KCl solution. The effects
of AOT concentration, aqueous pH, KCl concentration and phase volume ratio on the extraction efficiency of soybean protein
were tested. Suitability of reverse micelles of AOT and Triton-X-100/AOT mixture in organic solvent toluene for soybean protein
extraction was also investigated. The experimental results lead to complete forward extraction at the AOT concentration 120 mmol l−1, aqueous pH 5.5 and KCl concentration 0.8 mol l−1. The backward extraction with aqueous phase (pH 5.5) resulted in 100% extraction of soybean protein from the organic phase. 相似文献
996.
Melek Bor-Kucukatay Suleyman Demir Ramazan Akbay Dursun Dursunoglu Beyza Akdag Ender Semiz 《Molecular biology reports》2010,37(1):171-178
This study aimed to investigate the relationship between endothelial nitric oxide synthase Glu(298)Asp gene polymorphism and hemorheological parameters. Red blood cell (RBC) deformability, aggregation were measured using an ectacytometry, whole blood, plasma viscosities were determined by a viscometer. Restriction fragment length polymorphism was used to detect polymorphism. Plasma nitrite, nitrate concentrations were determined by Griess method. The genotype distribution of the control group was as follows: 50 (67.5%) GG, 21 (28.4%) GT, 3 (4.1%) TT. A 48 (57.8%) of the patients with CAD had GG, 28 (33.7%) GT, 7 (8.5%) of them TT genotype. RBC aggregation index of CAD patients with G allele was higher and t½ lower compared to controls carrying the same allele. The amplitude of RBC aggregation of healthy subjects with T allele, who are under increased cardiovascular risk was lower compared to control subjects with G allele. The results of this study indicate that, alterations in RBC aggregation seem to be a consequence of CAD, more than being a preexisting cause. Additionally, some compensatory mechanisms by causing decrements in RBC aggregation, may help regulation of circulation in healthy individuals with high cardiovascular risk. 相似文献
997.
This paper reviews the gear parameters responsible for loggerhead sea turtle (Caretta caretta) capture and mortality while taking into account the mitigation measures tested in the Mediterranean Sea. Incidental catch
is considered as one of the major threats for turtle survival; however, the loggerhead bycatch estimated in different areas
seems to be unrealistic, which highlights the need of a method for homogenising the estimates. Drifting longlines and bottom
trawls have the greatest impact on Mediterranean turtle populations, respectively in pelagic and demersal phase, while passive
nets (gillnets and trammel nets) seem to be responsible for the highest direct mortality, due to drowning. Most of the experiments
available for the Mediterranean are focused on drifting longline. The longline parameters, hook shape and size, bait type,
setting position and the reaction to sensory stimuli, strongly affect the sea turtle bycatch and mortality. Circle hooks have
the potential to reduce turtle mortality only in certain fisheries and areas; larger hooks are less likely to be swallowed
by turtles due to physical constraints of the mouth, reducing the mortality rate and the catch of juveniles; branchlines,
once ingested, appear to be one of the major causes of sea turtle mortality; squid bait, which consistently catches more turtles
than mackerel, and lightsticks, which strongly attract turtles, should be banned, at least in some areas and seasons. On the
contrary only two bottom trawl studies are available from the Mediterranean. Turtle excluder devices have been tested with
promising results in Turkey and Italy, even if the loss of large fish should be carefully investigated. For set nets no practical
solutions are available at this time. The analysis allows the conclusion that technical parameters affecting turtle bycatch
and mortality should only be studied one at a time, in order to avoid inconclusive results, studies on post-release mortality
should be implemented and finally fishermen cooperation is paramount in reducing turtle bycatch and mortality. 相似文献
998.
Frédéric-Antoine Dauchy Sébastien Dégrange Alain Charron Michel Dupon Yi Xin Cécile Bébéar Jeanne Maugein 《BMC microbiology》2010,10(1):93
Background
Mycobacterium intracellulare, a species of the Mycobacterium avium complex, may be the cause of severe lung, lymphatic node, skin and bone/joint infections, as well as bacteriemia. The goal of this work was to identify Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat (MIRU-VNTR) markers and to study their variability in a collection of isolates of M. intracellulare collected in humans. We studied 61 isolates collected in humans between 2001 and 2008, as well as the reference strain, M. intracellulare ATCC 13950. 相似文献999.
Elisa d'Aloisio Anna R Paolacci Arun P Dhanapal Oronzo A Tanzarella Enrico Porceddu Mario Ciaffi 《BMC plant biology》2010,10(1):101
Background
The Protein Disulfide Isomerase (PDI) gene family encodes several PDI and PDI-like proteins containing thioredoxin domains and controlling diversified metabolic functions, including disulfide bond formation and isomerisation during protein folding. Genomic, cDNA and promoter sequences of the three homoeologous wheat genes encoding the "typical" PDI had been cloned and characterized in a previous work. The purpose of present research was the cloning and characterization of the complete set of genes encoding PDI and PDI like proteins in bread wheat (Triticum aestivum cv Chinese Spring) and the comparison of their sequence, structure and expression with homologous genes from other plant species. 相似文献1000.
Many methods and tools are available for preprocessing high-throughput RNA sequencing data and detecting differential expression. 相似文献