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81.
82.
Schoenoplectus juncoides, a noxious weed for paddy rice, is known to become resistant to sulfonylurea (SU) herbicides by a target-site mutation in either of the two acetolactate synthase (ALS) genes (ALS1 and ALS2). SU-resistant S. juncoides plants having an Asp376Glu mutation in ALS2 were found from a paddy rice field in Japan, but their resistance profile has not been quantitatively investigated. In this study, dose–response of the SU-resistant accession was compared with that of a SU-susceptible accession at in vivo whole-plant level as well as at in vitro enzymatic level.  相似文献   
83.
It is known that pica, the consumption of non-nutritive substances such as kaolin, can be induced by administration of toxins or emetic agents in rats. In the present study, we examined the effects of intraperitoneal (i.p.) administration of cyclophosphamide on pica behavior and on the concentration of 5-hydroxyindoleacetic acids (5HIAA) in cerebrospinal fluid (CSF) in the following five strains of adult male rats: Sprague Dawley (SD), Wistar, Fischer 344 (F344), Wistar-Imamichi (WI) and Long Evans (LE). Cyclophosphamide (25 mg or 50 mg/kg) was injected (i.p.) into the rats and kaolin and food intake were measured at 24 hr after injection. The animals were anesthetized with urethane (1 g/kg) at 3 hr after injection of cyclophosphamide, and CSF was collected from the cisterna magna. WI and LE rats clearly showed pica behavior as compared with the other strains. In LE rats, the concentration of 5HIAA in CSF also increased in a dose-dependent manner of cyclophosphamide. The pretreatment with ondansetron (5-HT(3) antagonist) restored both changes (kaolin consumption and 5HIAA levels) induced by cyclophosphamide. These results suggest that the LE rat is sensitive to cyclophosphamide, that pica induced by cyclophosphamide mimics many aspects of emesis including the serotonergic response in the central nervous system and that use of the pica model would be a practical method for evaluating the effects of antiemetic drugs in addition to the mechanism of emesis.  相似文献   
84.
High-mobility group box 1 (HMGB1), a nonhistone chromosomal protein, has recently been suggested as a late mediator of the inflammatory cascade. Blood HMGB1 levels are increased in a number of human diseases, and HMGB1 has been suggested to be a useful marker for disease severity and prognosis. The objective of this study was to assess the clinical usefulness of HMGB1 in dogs. Plasma HMGB1 levels, as well as C-reactive protein (CRP), a typical canine inflammatory marker, were measured in dogs with various diseases, especially systemic inflammatory response syndrome (SIRS), and dogs that had undergone surgery. HMGB1 gradually increased and attained a maximum level 72 hr after surgery, whereas CRP increased rapidly, peaking at 24 hr. Although both HMGB1 and CRP levels were significantly increased in dogs with various diseases compared with the control dogs, no correlation was found between the HMGB1 and CRP values. HMGB1 levels in the SIRS group were significantly elevated compared with those in the non-SIRS group. However, the increase in HMGB1 levels above the reference range was not indicative of SIRS. Instead, the presence of increased HMGB1 and CRP levels above the reference ranges significantly affects the poor outcome of SIRS. The present study indicates that HMGB1 is a novel canine inflammatory marker and is distinct from CRP. However, the additional clinical value of HMGB1 measurement remains unclear, and further studies are warranted.  相似文献   
85.
Canine Visceral Leishmaniasis (CVL) is a widespread zoonotic disease with mandatory euthanasia of infected dogs determined by the Brazilian Ministry of Health. Development of vaccines against CVL may provide a prophylactic barrier, but transitory peak of antibody response detected by standard diagnostic techniques in vaccinated dogs may be interpreted as natural infection. Accordingly, the aim of the present study was to sequentially evaluate total and IgG subclasses response between naturally Leishmania-infected and dogs vaccinated with Leishmune(?). A total of 172 mongrel dogs were divided in four groups: Group 1 (G1) with 45 clinically healthy dogs, Group 2 (G2) and Group 3 (G3) with 45 dogs naturally infected by Leishmania sp. each, symptomatic and asymptomatic respectively, and G4 (G4) with 37 healthy dogs submitted to a complete protocol of a commercially available vaccine against CVL, monitored and evaluated in 5 different chronological moments (M0-M4) up to 180 days after M0. Total IgG, IgG1 and IgG2 were unable to differentiate between infected (G2 and G3) and vaccinated (G4) dogs, demonstrating that polyclonal commercial antibodies do not distinguish these groups apart. Total and IgG subclasses antibodies were not detected until 21 days of the second vaccination dose; however, seroconversion was observed on 21 days and sustained positivity up to 6 months after the vaccination start. A peak of antibodies response was observed on 90 days (M3), when results for total IgG, IgG1, IgG2, IgG3 and IgG4 where highly significant when compared to M0 (P<0.0001). Neither total IgG nor IgG1 effectively differentiated between infected (G2 and G3) and vaccinated (G4) dogs. In conclusion, despite dogs may test serologically negative immediately after vaccination against CVL with Leishmune(?), subsequent seroconversion, antibody peak and positivity up to six months may lead vaccinated dogs to be mistakenly identified as naturally infected dogs during this period.  相似文献   
86.
Because foam cell formation in macrophages is believed to play an essential role in the progression of early atherosclerotic lesions in vivo, prevention of foam cell formation is considered to be one of the major targets for the treatment of atherosclerosis. The present study examined the inhibitory effect of 50 crude plant extracts on foam cell formation. Among those crude extracts, Zizyphi Fructus (ZF) and Zizyphi Semen (ZS) extracts significantly inhibited the foam cell formation induced by acetylated LDL. Furthermore, triterpenoids such as oleanonic acid, pomolic acid, and pomonic acid were the major active compounds, and triterpenoids containing a carboxylic acid at C-28 play an important role in the inhibitory effect on foam cell formation in human macrophages. These data suggest that triterpenoids in Zizyphus jujuba , the plant source of ZF and ZS, may therefore be useful for the prevention of atherosclerosis.  相似文献   
87.
It is well known that methyl mercaptan is porduced by the microbiological decomposition of methionine1),2),3). According to Kondo 4) and Onitake 1)not only hydrogen sulfide, but also methyl mercaptan were produced from cystine by E. coli and Proteus vulgaris in the medium containing one of glucose, lactose, sucrose, glycerin or histidine. Moreover, Onitake 1) found that methyl mercaptan was produced by the action of E. coli in the medium containing hydrogen sulfide and a trace of ethyl alcohol, and that evolution of methyl mercaptan began only 5 minutes after the start of experiment in the medium containing methionine, but it began after 12hrs in the medium containing 1-cystine and glucose. According to Birkinshaw, Findlay and Webb5) methyl mercaptan was found in the medium containing glucose, sulfate and other mineral salts, inoculated by Schizophyllum commune. In the same cultural condition as given above, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide were detected by Challenger and Chartons 5) from the data presented above, in addition to microbiological formation of methyl mercaptan from methionine, the possibility cannot be excluded of methyl mercaptan formation by microbes from cystine, sulfate or hydrogen sulfide in the medium containing one of organic compounds such as sugars, glycerin, histidine and ethyl alcohol, etc.  相似文献   
88.
To characterize the regulation site and manner of the abundant nodulation in the soybean (Glycine max (L.) Merr.) cv. Kitamusume, three grafting eperiments were carried out as follows: reciprocal wedge grafting and inter-cultivar approach grafting between Kitamusume and a normal nodulating cultivar, Toyosuzu, as well as wedge grafting of scions of the supernodulating mutant En6500 onto either Kitamusume or Toyosuzu rootstock. In the reciprocal wedge grafting, the number of nodules per shoot dry weight and average weight per nodule in the grafted plants were consistent with those exhibited by the genotype of their rootstocks. Approach grafting did not affect the number of nodules per shoot dry weight on either side of the inter-cultivar approachgrafted plant. Although grafting of the mutant scion resulted in the loss of the autoregulatory response from the roots of both cultivars, difference in the number of nodules per g shoot dry weight still remained between the two cultivars. These results suggested that the abundant nodulation in Kitamusume is controlled by the root in a non-systemic manner and is independent of the autoregulation mechanism.  相似文献   
89.
Island ecosystems differ from mainland ecosystems in their long-term isolation. On Sado Island, Japan, cattle grazing in the past gradually changed forests into grasslands, thereby altering the diversity of indigenous insects. We compared ground-dwelling beetle diversity on Sado Island to that on the nearby mainland. Contrary to previous reports, the island isolation effect resulted in lower γ and β diversity than on the mainland, because of the low species richness of beetles with low dispersal abilities. Few flightless beetles could invade Sado Island, even when the beech forests on the island were relatively adjacent to those on the mainland. Such a history of ecosystem formation could be the general pattern for continental-island mountain forests that were never connected to those of the mainland. We did not observe low α diversity of ground-dwelling beetles, suggesting that the cattle grazing history of the island has not changed environmental conditions for ground-dwelling beetles enough to reduce their diversity. In addition, cattle grazing increases the abundance of merdivorous insects by increasing the abundance of their food resource. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
90.
The inner cellular structure of microconidia of Magnaporthe oryzae was examined using fluorescent probes and electron microscopic techniques. The volume of the nucleus relative to the cell was significantly larger in microconidia than in macroconidia or vegetative hyphae, similar to observations for spermatia of other fungi. Selective fluorescent staining revealed that cytosolic RNA was less abundant in microconidia than in macroconidia and germ tubes, suggesting that general metabolic activity in microconidia is low. Consistently, GFP expression driven by the TrpC promoter was highly active during the formation of phialides and microconidia but gradually decreased as the microconidia matured. Such data suggest that microconidia are in a quiescent or dormant state.  相似文献   
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