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61.
Tick DNA samples from cattle in Xinjiang Uygur Autonomous Region Area, China, were examined for Rickettsia infection by citrate synthase gene-based PCR and sequencing. Four positive samples were detected from Haemaphysalis danieli and high levels of similarity were found with recently detected 'Candidatus Rickettsia principis.'  相似文献   
62.
The heat shock protein 70 (hsp70) genes of Babesia gibsoni, B. canis canis, B. canis vogeli, and B. canis rossi isolated from infected dogs were cloned by polymerase chain reaction (PCR) and sequenced. In the nucleotide sequence and the predicted amino acid sequence of the gene, the parasites were very similar to each other. The nucleotide sequences of the hsp70 gene had more variety than those of 18S nuclear subunit ribosomal DNA (18S rDNA). A phylogenetic analysis of these sequences and comparisons with sequences from other Babesia and Theileria species revealed that all canine babesial isolates analyzed in the present study were closely related to each other and formed one cluster. Additionally, a phylogenetic analysis of Babesia and Theileria species showed that these parasites could be divided into three groups: group A including canine babesial isolates, B. divergens, B. odocoilei, B. bovis, B. caballi, and B. ovis; group B including Theileria annulata, T. orientalis, and T. cervi; and group C including B. microti and B. rodhaini. These results suggested that a phylogenetic analysis of the hsp70 gene sequence might be helpful in classifying Babesia and Theileria species, and that canine babesial isolates might be closely related to each other, indicating their evolution from the same ancestry.  相似文献   
63.
Ehrlichia muris DNA was detected in the blood of sika deer (Cervus nippon yesoensis) by species-specific PCR based on the citrate synthase gene, which was shown to be more sensitive than species-specific PCR based on the 16S rRNA gene. Among 102 deer examined, one deer was positive. Deer may be a possible mammalian reservoir of E. muris.  相似文献   
64.
Seed storage proteins of 131 Japanese Norin wheat (Triticum aestivum) varieties were fractionated by sodium dodecyl sulfate polyacrylamide gel electrophoresis to determine allelic make-up in varieties at each of three loci that control high-molecular-weight (HMW) glutenin subunits. Three alleles were identified at the Glu-A1 locus, six at the Glu-B1 locus and five at the Glu-D1 locus. Twenty-four different, major glutenin HMW subunits were identified and each contained three to five subunits and seventeen different glutenin subunit patterns were observed for 19 subunits in the 131 Japanese Norin varieties. Fourteen alleles were identified by comparison of subunit mobility with that previously found in hexaploid wheat. Japanese Norin varieties showed a specific pattern of allelic variation in glutenin HMW subunits, different from that of Chinese and other country common wheats in allelic frequency at Glu-1 loci. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
65.
Variously substituted benzyl derivatives of chloronicotinyl insecticides were synthesized with a wide range of substituents including halogens, NO2, CN, CF3 and small alkyl and alkoxy groups at the ortho, meta and para positions, as well as multiple‐substituted benzyl analogues. Their binding activity to the α‐bungarotoxin binding site in housefly (Musca domestica) head membrane preparations was measured. Among the compounds tested, the activity of the meta‐CN derivative was the highest, being 20–100 times higher than those of imidacloprid, acetamiprid and nitenpyram. The synergized insecticidal activity against houseflies was also measured for selected compounds with the metabolic inhibitor, NIA16388 (propargyl propyl phenylphosphonate). For the nitromethylene analogues, including both benzyl and pyridylmethyl analogues, higher binding activity usually resulted in higher insecticidal activity. © 2000 Society of Chemical Industry  相似文献   
66.
A demand system analysis was conducted to examine the substitute relationships between tuna and skipjack tuna in the Japanese market. Data from the Annual Report on Family Income and Expenditure Survey from 1965 to 2006 were used for the analysis using the almost ideal demand system (AIDS). Results suggest that skipjack tuna can be a strong substitute for tuna, while other fish groups are not a clear substitute. Our analysis of substitute relationships among fish species in a market indicates that this is a factor that should be considered for better fisheries resource management. For instance, even under a situation where one fish species is underexploited, proper attention to its fishery management is necessary if the fish is a strong substitute for another popular fish species in the market.  相似文献   
67.
The binding activity of imidacloprid and related compounds to nicotinic acetylcholine receptors (nAChR) of house flies was measured by use of radioactive α-bungarotoxin as a ligand. Variations in the activity were examined three-dimensionally using comparative molecular field analysis (CoMFA). The CoMFA results suggest that one conformer among the four stable ones is active and provide support for one of the proposed binding models for this class of compound, in which the nitrogen atom of the pyridine ring and the nitrogen atom at the 1-position of the imidazolidine ring interact with the hydrogen-donating and electron-rich sites of nAChR, respectively. The CoMFA field map showed that the nitroimino moiety and a portion of the imidazolidine ring were mainly surrounded by a sterically and electrostatically sensitive region of nAChR. © 1998 Society of Chemical Industry  相似文献   
68.
In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperatureleaf stagelight,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity.  相似文献   
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