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61.
Pietro Massardo Franco Bettarini Paolo Piccardi Angelo Longoni 《Pest management science》1983,14(5):461-469
A new class of compounds, derived from hydroquinones, has been synthesised and bioassayed for juvenile hormone activity on yellow mealworm (Tenebrio molitor), confused flour beetle (Tribolium confusum), and mediterranean flour moth (Anagasta kuehniella). Structure-biological activity relationships of the most significant products are tabulated and discussed. Two of the new compounds, 1, 4-bis(5-chloropent-4-ynyloxy) benzene (I) and 1-(5-chloropent-4-ynyloxy)-4-phenoxybenzene (II), showed outstanding activity in morphogenetic assay with T. molitor, and good field persistence. Product II is of particular interest for the control of various Homopteran species, mosquitoes, stored product pests and fire ants. 相似文献
62.
Paolo Piccardi Pietro Massardo Franco Bettarini Angelo Longoni 《Pest management science》1980,11(4):423-431
In the search for new juvenile hormone analogues (JHAs), a general approach was chosen based on the substitution of the isoprene unit, that carries the epoxy function in the natural hormone JHIII, by 3,3,3-trichloropropyl, 2,2-dichlorocyclopropyl- methyl, 3,3-dichloroallyl, or 3-chloroprop-2-ynyl groups. Accordingly, several terpenoid aromatic JHAs were prepared with, or without, oxygen atoms in the aliphatic chain. Structure-biological activity relationships of the most active compounds toward the yellow mealworm (Tenebrio molitor) and the large cabbage white butterfly (Pieris brassicae) are given. With a view to preparing synthetically accessible analogues, some alkyl phenyl ethers were also made, which were not branched in the aliphatic chain and were related terminally to the most active compounds. They were only moderately active against insects when tested for morphogenetic activity, but exhibited a good field persistence. The occurrence of a moderate acaricidal activity among these analogues prompted the examination of several 1,4-disubstituted-phenyl derivatives. The ovicidal effectiveness of these products against a susceptible strain of the two-spotted spider mite, Tetranychus urticae, was ten or 100 times higher than that of the well known and highly potent JHAs. 相似文献
63.
A total of 74 embryos and fetuses were used in a comparative analysis of the epithelium of the non-glandular stomach compartments of merino sheep during development. The mechanical protection showed by the tegumentary epithelium in the superficial layers of the rumen, reticulum and omasum is supported by a buffer system of neutral mucopolysaccharides secreted by the deeper strata. Neutral mucopolysaccharides first appeared in epithelial cells at 46 days of fetal life. Acid mucopolysaccharides, mucins, and mucoid compounds were not detected. Growth curves and formulas were constructed for the epithelial layers. 相似文献
64.
A 27-year-old stand of flooded gum (Eucalyptus grandis Hill ex Maiden) in the North Coast Region of N.S.W. was assessed in relation to aboveground distribution and turnover of organic matter, nitrogen, phosphorus, calcium, magnesium and potassium. Of the 453 t ha?1 of aboveground organic matter present, 394 t was in the tree, 42 t in the understorey and 28 t in the forest floor. The total nitrogen, phosphorus, calcium, magnesium and potassium contents of the stand were 739, 44, 1254 and 658 kg ha?1, respectively, and the understorey contained 35%, 35%, 16%, 24% and 49% of the above-ground distribution of these nutrients respectively. Although the developing rainforest understorey comprised a relatively small portion (9.3%) of the total aboveground biomass, it played a disproportionate role in nutrient accumulation and uptake, and had an annual net accumulation of 14%, 55%, 59%, 30%, 44% and 69% of the aboveground organic matter, nitrogen, phosphorus, calcium, magnesium and potassium respectively. The net annual removal from the soil was 30, 1, 38, 5 and 31 kg ha?1 year?1 for nitrogen, phosphorus, calcium, magnesium and potassium, respectively. Flooded gum had very high accumulations of calcium in the bark and the effect of this in nutrient cycling is discussed. An idealised management system, to exploit and optimise the nutrient cycle of flooded gum, has been hypothesided. 相似文献
65.
An electronic sphygmomanometer which functions on oscillometric principles, was used to measure arterial blood pressure in foals. Its accuracy was assessed by comparison with results obtained by direct measurement in anaesthetised pony foals, aged 34 to 64 days. Correlations between data obtained by the two methods were highly significant but the sphygmomanometric readings were consistently lower than those obtained by direct measurement. An equation was derived from the pooled values for mean, systolic and diastolic pressure measurements. This was used as a correction factor when the oscillometric method was employed in the field on Thoroughbred foals, during the first three days post partum, and on pony foals during the first day only. There were no significant differences between systolic, diastolic and mean values in Thoroughbreds on Days 1, 2 or 3 after birth. Measurements recorded on the first day after foaling were significantly lower (P less than 0.025) in ponies than in Thoroughbreds. Blood pressure measurements in Thoroughbreds and ponies were substantially higher than those reported previously using the ultrasonic Doppler technique. 相似文献
66.
67.
L Lamontagne P Marois G Marsolais E Di Franco R Assaf 《Canadian journal of veterinary research》1981,45(2):177-181
When treated with formaldehyde, Tween 80, sodium oleate and Nonidet P-40, avian infectious bronchitis virus, porcine transmissible gastroenteritis virus, neonatal calf diarrhea coronavirus, porcine hemagglutinating encephalomyelitis virus as well as the human coronavirus show similar inner structures by negative staining. The first one is an inner membranous bag. This structure could be evaginated following treatments used and does not show the characteristic projections of coronaviruses. Subsequently, the inner fold could be separated from the outer membrane at the point of junction between these two membranes. Each virus does not react in the same way to the action of the different products. The transmissible gastroenteritis virus appears more sensitive to treatments than other viruses. On the other hand, the hemagglutinating encephalomyelitis virus is the most resistant. The variable sensitivities of these viruses are not related to the type of host-cells. Also, a second internal structure, which is more dense than the viral particle, encircles partially the aperture of the internal tongue-shaped structure and seems to emerge from the viral particle through the aperture of the inner bag. 相似文献
68.
Y Lignereux S Regodon M H Marty A Franco 《Canadian journal of veterinary research》1991,55(4):382-383
The proposed technique consists of placing a catheter in the olfactory recess of the lateral ventricle of the brain of a sheep. Twenty adult ewes were used in the study. The olfactory recess is in the frontal region 25 +/- 3 mm below the skin, just caudal to the line joining the supraorbital foramen and approximately 8-10 mm from the median plane. The approach is relatively easy under normal experimental conditions. The wall of the olfactory bulb, however, is fragile, and the animals must not have been injured by Oestrus ovis. 相似文献
69.
Influence d''infections préalables sur l''evolution de la pleuro-pneumonie porcine expérimentale chez des porcs exempts d''organismes pathogènes spécifiques. 下载免费PDF全文
P Marois E Di Franco G Boulay P Flipot R Assaf G Lamoureux 《Canadian journal of veterinary research》1989,53(4):394-399
This study was designed to determine in six-week old specific pathogen free pigs, the effect of previous experimental exposure to Mycoplasma hyopneumoniae and transmissible gastroenteritis virus on a challenge infection with Actinobacillus pleuropneumoniae. Pigs exposed simultaneously to M. hyopneumoniae and transmissible gastroenteritis virus appeared more resistant to challenge (one week later) with A. pleuropneumoniae. Four pigs out of a group of ten died following the challenge infection, compared to all ten pigs in the control group not submitted to previous infections. Clinical signs and lesions were also less severe in the previously infected group than in the control group. Pigs submitted to a single previous infection with M. hyopneumoniae only appeared to be less resistant to the challenge infection than pigs submitted to the dual previous infection with M. hyopneumoniae and the transmissible gastroenteritis virus. A correlation was found between the resistance of pigs to the challenge infection and their serum gammaglobulin levels. 相似文献
70.
Antonio Ippolito Leonardo Schena Franco Nigro Vincenza Soleti ligorio Thaer Yaseen 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(8):833-843
Two primers, specific for Phytophthora nicotianae (Pn6) and P. citrophthora (Pc2B), were modified to obtain Scorpion primers for real-time identification and detection of both pathogens in citrus nursery soils and roots. Multiplex PCR with dual-labelled fluorogenic probes allowed concurrent identification of both species ofPhytophthora among 150 fungal isolates, including 14 species of Phytophthora. Using P. nicotianaespecific primers a delayed and lower fluorescence increase was also obtained from P. cactorumDNA. However, in separate real-time amplifications, the aspecific increase of fluorescence from P. cactorum was avoided by increasing the annealing temperature. In multiplex PCR, with a series of 10-fold DNA dilutions, the detection limit was 10 pg l-1 for P. nicotianaeand 100 pg l–1 for P. citrophthora, whereas in separate reaction DNA up to 1 pg l-1 was detected for both pathogens.Simple and rapid procedures for direct DNA extraction from soil and roots were utilised to yield DNA whose purity and quality was suitable for PCR assays. By combining these protocols with a double amplification (nested Scorpion-PCR) using primers Ph2-ITS4 amplifying DNA from the main Phytophthora species (first round) and PnB5-Pn6 Scorpion and Pc2B Scorpion-Pc7 (second round), it was possible to achieve real-time detection of P. nicotianaeand P. citrophthora from roots and soil. The degree of sensitivity was similar to that of traditional detection methods based on the use of selective media. The analyses of artificially and naturally infested soil showed a high and significant correlation between the concentration of pathogen propagules and the real-time PCR cycle threshold. 相似文献