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71.
The fungicidal activity of analogues of beta-thujaplicin, a natural product responsible for the durability of heartwood of several cupressaceous trees, was investigated in vitro on the growth of different white and brown rot fungi involved in wood biodegradation, Coriolus versicolor, Phanerochaete chrysosporium, Poria placenta and Gloephyllum trabeum. The study shows that 2-hydroxycyclohepta-2,4,6-trienone (tropolone), easily prepared according to a literature procedure, possesses interesting fungicidal activity when compared to beta-thujaplicin, azaconazole, tebuconazole and copper oxine, which suggests this compound should be examined further as a potential biocide for wood preservation. 相似文献
72.
Christian Pillonel 《Pest management science》1995,43(2):107-113
Experiments with intact cells and submitochondrial fractions of Pythium aphanidermatum (Edson) Fitz. indicated an interference of benzimidazole-N-sulfonamides with the NADH- or succinate-driven electron transport system between cytochromes b and c. Comparison with Ustilago maydis (DC) Corda and Botrytis cinerea Pers. ex Fr. revealed that this effect is Oomycetes specific. The molecular interaction between benzimidazole-N-sulfonamides and the mitochondrial cytochrome b/cb>1 b> complex from P. aphanidermatum has been investigated. Binding assays with [14C]52232 RP (dimefluazole) indicated a time- and dose-dependent labelling of two proteins. The molecular mass of one labelled protein and the competition of the binding with antimycin A suggest that benzimidazole-N-sulfonamides interact with the Qb>1 b>-centre of cytochrome b. Furthermore, experiments with doubly labelled [3H][14C]CGA 323103 revealed a possible irreversible inactivation of the b/cb>1 b> complex leading to covalent linkage of the dimethylsulfonamoyl moiety to the target site. 相似文献
73.
The study was designed to determine differences between normal mares and mares with endometrial pathology in the inflammatory response after bacterial challenge. Six normal mares (biopsy category I) and 4 mares with pathological endometrial changes (biopsy category II) were given an intrauterine infusion of b2;-hemolytic streptococci on the second day of estrus. All mares had a similar kind of inflammatory response after the bacterial inoculation as assessed by rectal and vaginal examinations. There were no significant differences in the amount of discharge, uterine tone, uterine size and cervical relaxation between the groups. Leukocytic response, as determined by endometrial smears and biopsies, was of the same magnitude in both groups. Two mares from the pathological group were not able to eliminate the infection, but had vaginal discharge and bacteriologically positive uterine swabs until the end of the experiment. It is concluded that the inability of some mares to clear uterine infections cannot be explained by a deficient inflammatory response. 相似文献
74.
Sera from adult cattle with fluke-infected and normal livers were analyzed for b3;-GT and AspAT activities. The analyses revealed no significant increases in either b3;-GT or AspAT values of the animals with fascioliasis as compared with the non-infected animals. The advanced chronic stage of the infection characterized by hepatic fibrosis, limited injury of parenchyma and low fluke burdens may explain the lack of enzymatic increase. 相似文献
75.
Tidholm A Falk T Gundler S Svensson H Ablad B Sylvén C 《Research in veterinary science》2003,75(3):195-201
Nineteen euthyroid dogs of 12 breeds with echocardiographic signs of dilated cardiomyopathy (DCM) and radiographic and clinical signs of congestive heart failure (CHF) were evaluated in a randomised, double-blind, and placebo-controlled study. The dogs received either thyroxine or placebo as an adjunct to digoxin, furosemide and propranolol. The group assignment of individual dogs and serum concentrations of thyroid hormones remained unknown to owners and investigators during the entire study period. Dogs were evaluated clinically and with electrocardiography (ECG), thoracic radiography, echocardiography and measurement of total thyroxine (tT4) and thyroid stimulating hormone (TSH) before beginning of the trial, and then one week, 2 months, 6 months and yearly after initial examination, and, when applicable, at the time of euthanasia. End-point of the study was euthanasia (n = 17) due to severe congestive heart failure or sudden death (n = 2). Survival times ranged from 17 to 1030 days (median 187 days) in the placebo group, and from 18 to 1000 days (median 73 days) in the treatment group. There was no statistically significant difference in survival times between the treatment group and the placebo group (p = 0.46). Post mortem and histopathologic examinations revealed the attenuated wavy fiber type of DCM in 11 dogs, and myocardial infarcts, arteriosclerosis and chronic valvular disease in one dog. In conclusion, there was a wide range in survival times of dogs treated with digoxin, furosemide and propranolol. Adding thyroid hormones to the treatment did not significantly influence survival. 相似文献
76.
《Biological conservation》2002,106(3):365-372
The lizard Zootoca vivipara has both oviparous and viviparous populations which belong to distinct clades. This study aims to elucidate the geographic distribution, phylogeography and conservation priority of the oviparous subspecies, Zootoca vivipara carniolica, that has recently been identified in Slovenia. We studied seven Slovenian populations, two northeastern Italian populations and five northwestern Italian populations. The seven cytochrome b haplotypes that we identified from the Slovenian and Italian oviparous populations form a monophyletic basal clade. The high homogeneity of the Slovenian and northeastern Italian populations (nucleotide diversity π=0.06%) is a striking contrast with the pattern observed in northwest Italy where each of the five populations studied presents a private haplotype (π=1.03%). The results obtained suggest that all the extant lineages of Z. v. carniolica have originated in an Italian refuge. The reproductive and phylogenetic distinctiveness of Z. v. carniolica clearly justifies conservation of its populations, especially in Italy where the highest genetic diversity and the most ancestral haplotype were observed. 相似文献
77.
To investigate the action of dinotefuran (MTI-446, 1-methyl-2-nitro-3-(tetrahydro-3-furylmethyl)guanidine), a recently developed insecticide, on insect nicotinic acetylcholine receptors (nAChRs), we determined the potencies of the compound and 15 analogues in inhibiting the specific binding of [3H]epibatidine (EPI), a nAChR agonist, and [3H]alpha-bungarotoxin (alpha-BGT), a competitive nAChR antagonist, to the nerve cord membranes of American cockroaches (Periplaneta americana). Racemic dinotefuran inhibited [3H]EPI binding with an IC50 of 890 nM and [3H]alpha-BGT binding with an IC50 of 36.1 microM. Scatchard analysis indicated that the dinotefuran inhibition of [3H]EPI binding was a competitive one. Slight structural modification caused a drastic reduction in potency; only four analogues were found to be equipotent to or more potent than dinotefuran. Chloropyridinyl and chlorothiazolyl neonicotinoid insecticides displayed two or three orders of magnitude higher potency than dinotefuran. There was a good correlation between the IC50 values of tested compounds obtained with [3H]EPI and those obtained with [3H]alpha-BGT. A better correlation was observed between 3-h knockdown activities (KD50) against German cockroaches (Blattella germanica) and IC50 values obtained from [3H]EPI assays than between 24-h lethal activities (LD50) and IC50 values. While the results indicate that dinotefuran and its analogues interact with the ACh-binding site in cockroach nAChRs, it remains to be elucidated why they displayed lower potencies than those expected based on their insecticidal activities. 相似文献
78.
79.
80.
AIM: To explore the effect of the pretreatment of hypertonic saline (HTS) in hepatic ischemia reperfusion (I/R) injury.METHODS: The rats were divided into sham group (sham group), ischemia reperfusion group (IR group) and pretreatment of hypertonic saline group (HTS group). Partial hepatic ischemia reperfusion model was used. The rats were sacrificed at the time of 1 h, 3 h, 6 h, 12 h and 24 h after reperfusion in each group, respectively. Blood samples were obtained to examine ALT. The expression of the CD11b/CD18 (Mac-1) on the neutrophils was analyzed by flow cytometry. RT-PCR and Western blotting were used to examine the expression of intercellular adhesion molecule-1 (ICAM-1) in livers and chromatometry was performed to detect the activity of myeloperoxidase (MPO) in livers. The morphology of hepatocytes and the structure of sinusoid were observed by histological examinations. RESULTS: ① HTS pretreatment decreased the level of ALT at the time points of 3 h, 6 h and 12 h after reperfusion (P<0.05). ② Mac-1 expression in HTS group was lower at 6 h and 12 h after reperfusion compared with IR group (P<0.05). ③ MPO activity in HTS group was lower at 6 h, 12 h and 24 h compared with IR group (P<0.05). ④ RT-PCR and Western blotting analysis indicated that the pretreatment of HTS inhibited the expression of ICAM-1 in livers after reperfusion. ⑤ Moderate hepatocyte swelling and few neutrophil infiltration were observed in HTS group.CONCLUSION: Pretreatment with HTS has the effect on hepatic ischemia reperfusion injury by inhibiting the expression of Mac-1 on circulating neutrophils and the expression of ICAM-1 in the liver. 相似文献