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21.
Transgenic potato and rice plants were generated by the introduction of human P450 species, CYP1A1, CYP2B6, CYP2C9 and CYP2C19, which metabolized a number of herbicides, insecticides and industrial chemicals. The transgenic potato plant T1977 co-expressing CYP1A1, CYP2B6 and CYP2C19 genes showed remarkable cross-resistance to several herbicides with different structures and modes of action due to metabolism of these herbicides by the P450 species expressed. The transgenic rice plant 2C9-57R2 expressing CYP2C9 gene showed resistance to sulfonylureas, and the transgenic rice plant 2C19-12R1 expressing CYP2C19 gene showed cross-resistance to certain herbicides with different structures and modes of action. These transgenic plants appear to be useful for herbicide resistance as well as phytoremediation of environmental contaminants.  相似文献   
22.
Renal effects of the selective alpha(2)-adrenoceptor agonist, medetomidine, were investigated in anesthetized dogs. Animals were administered medetomidine 20 and 40 microg/kg intravenously (IV) and 80 mug/kg intramuscularly (IM) or 1 ml of saline IV. Urine and blood samples were collected before and at 30, 60, 90 and 120 min following medetomidine injection. Mean arterial blood pressure (MABP), renal blood flow (RBF), glomerular filtration rate (GFR), urine volume (U(v)), urine osmolality (U(osm)), free water clearance (C(H2O)), fractional clearance of sodium (F(Na)), plasma osmolality (P(osm)), plasma glucose levels and plasma antidiuretic hormone (ADH) concentrations were measured. The results showed that IV administration of medetomidine initially increased MABP 5-15 min followed by long-lasting decrease. The initial hypertension was not observed after IM administration, which was accompanied by a more profound hypotensive effects. RBF, GFR, U(v), C(H2O) increased after IV injection and decreased after IM. Medetomidine increased FNa and Posm and decreased U(osm). Plasma glucose levels initially increased and subsequently decreased. Plasma ADH concentration was decreased by IV injection but increased by IM administration. Our data imply that: 1) IV administration of medetomidine at dose rates of 20 and 40 microg/kg results in profound diuresis up to 2 hr; 2) Suppression of ADH release from the CNS is one of the mechanisms of medetomidine-induced diuresis although it may not be the principal one.  相似文献   
23.
We evaluated the immunotoxicity of deoxynivalenol (DON), a Fusarium mycotoxin, on bovine and porcine neutrophils in vitro by using two function parameters, luminol-dependent chemiluminescence and random migration under agarose. A 2-hr DON treatment suppressed the chemiluminescence of bovine and porcine cells by 42% and 35% (on average) at 10(-5)M, and by 19% and 26% at 10(-6)M. Slight suppression was observed at concentrations lower than 10(-6)M. However, after an 18-hr DON treatment, random migration of neutrophils of both species remained unaffected, even at the highest concentration (10(-5)M). Although further extensive studies are needed, to our knowledge this is the first study to have revealed in vitro that DON can affect neutrophil function.  相似文献   
24.
Bovine and canine chromogranin A were extracted and purified from each specie's adrenal glands. Isolated bovine 70 kDa protein showed 100% identity to bovine CgA reported previously, whereas isolated canine 68 kDa protein showed 83.3% identity to bovine CgA by the NH(2)-terminal amino acid sequence analysis. Rabbit antibody to purified bovine protein (CgA) was found to immunologically cross-reacted with purified canine protein (CgA). In sandwich ELISA with anti-bovine CgA, concentration-dependent curves were obtained ranging from 0.3 to 20 mug/ml for canine CgA. From these findings, sandwich ELISA with anti-bovine CgA is found to be useful to determine the concentration of canine CgA.  相似文献   
25.
Several studies have indicated that viruses require a specific cytoskeletal structure for replication in host cells. In this study, we examined the role of actin fiber in the replication of canine distemper virus (CDV), belonging to the Morbillivirus genus of the family Paramyxoviridae. For this purpose, we used two actin depolymerizing agents, cytochalasin-D (C-D) and mycalolide-B (ML-B). In Vero cells, C-D disrupted actin fibers distributed in the cytosol, but peripheral actin fibers remained intact. On the other hand, ML-B completely disrupted the actin fibers distributed in both areas. Treatment of Vero cells with C-D or ML-B inhibited the replication of CDV. Double staining of CDV-infected Vero cells with antibody to N-protein and rhodamine-phalloidin revealed the presence of N-protein in mid-cytoplasm. However, the N-protein was specifically localized at the submembrane region in the presence of C-D, whereas it was clustered in the presence of ML-B. Viral mRNA levels of N- and H-proteins were rather increased by treatment with C-D or ML-B. The treatment with ML-B strongly inhibited N-protein expression, whereas C-D only slightly inhibited N-protein expression. These results suggest that actin microfilaments distributed in the cytoplasm and on the membrane region in host cells may have a different role in the process of CDV replication.  相似文献   
26.
Despite the abundance of "sandwich" complexes, in which two cyclic aromatic hydrocarbon ligands flank a metal center, this motif has not been extended to sheets of multiple metal atoms. We prepared and isolated two such compounds. In the first, three palladium centers form a planar triangular array, capped by chlorides, between two cycloheptatrienyl ligands. In the second, a pentapalladium sheet adopts an edge-sharing triangle-trapezoid skeleton between two naphthacene rings. The compounds were characterized by x-ray crystallography and nuclear magnetic resonance spectroscopy. The nature of bonding in the clusters was analyzed by quantum calculations.  相似文献   
27.
BACKGROUND: QoI fungicides, inhibitors of mitochondrial respiration, are considered to be at high risk of resistance development. In several phytopathogenic fungi, resistance is caused by mutations (most frequently G143A) in the mitochondrial cytochrome b (cytb) gene. The genetic and molecular basis of QoI resistance were investigated in laboratory and field mutants of Botryotinia fuckeliana (de Bary) Whetz. exhibiting in vitro reduced sensitivity to trifloxystrobin. RESULTS: B. fuckeliana mutants highly resistant to trifloxystrobin were obtained in the laboratory by spontaneous mutations in wild‐type strains, or from naturally infected plants on a medium amended with 1–3 mg L?1 trifloxystrobin and 2 mM salicylhydroxamic acid, an inhibitor of alternative oxidase. No point mutations were detected, either in the complete nucleotide sequences of the cytb gene or in those of the aox and Rieske protein genes of laboratory mutants, whereas all field mutants carried the G143A mutation in the mitochondrial cytb gene. QoI resistance was always maternally inherited in ascospore progeny of sexual crosses of field mutants with sensitive reference strains. CONCLUSIONS: The G143A mutation in cytb gene is confirmed to be responsible for field resistance to QoIs in B. fuckeliana. Maternal inheritance of resistance to QoIs in progeny of sexual crosses confirmed that it is caused by extranuclear genetic determinants. In laboratory mutants the heteroplasmic state of mutated mitochondria could likely hamper the G143A detection, otherwise other gene(s) underlying different mechanisms of resistance could be involved. Copyright © 2012 Society of Chemical Industry  相似文献   
28.
29.
For efficient production of Japanese eel Anguilla japonica eggs, knowledge of the status of the sexual maturity of potential broodstock females is important because this status directly influences the time required to produce mature eggs by successive hormone doses. Here we apply an eye index (relative eye size) to evaluate the gonadal status of feminized A. japonica, which were induced by administration of estradiol-17β. Examination of gonad somatic and eye indexes of 267 feminized eels, cultivated for 12–56 months, revealed a significant correlation between these two indexes. Artificial maturation of 35 feminized eels showed that the number of hormone injections administered before ovulation was significantly lower as the eye index score increased, indicating availability of this noninvasive method of predicting sexual maturity of feminized eel. There was no correlation between eye index and fertilization rate, hatching rate, or larval survival rate, suggesting that sexual maturity before hormonal treatment does not affect egg quality.  相似文献   
30.
Monoconidial strains of Venturia nashicola Tanaka et Yamamoto were isolated from Japanese or Chinese white pear trees which had never been treated with sterol demethylation inhibitors (DMIs) and their baseline sensitivities to fenarimol were determined by mycelial growth tests on fungicide-amended culture media. Strains were also obtained from Japanese pear orchards, which had been intensively treated with DMIs for several years and monitored for the shifts of fenarimol sensitivity in comparison with the baseline sensitivity. Results suggested slight shifts to lower fenarimol sensitivity in strains isolated from DMI-treated Japanese pear orchards. However, in inoculation tests on pear seedlings, fenarimol still provided adequate control of V. nashicola strains with reduced sensitivity to fenarimol in vitro, suggesting that the performance of this fungicide will still be maintained in the field. © 1998 Society of Chemical Industry  相似文献   
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