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121.
Des informations sur la biologie et la diffusion des principaux insectes nuisibles aux eucalyptus en Italie sont données, ainsi que sur l'importance de leurs dégats et sur les méthodes de lutte les plus couramment employées. En plus des quelques espèces polyphages, qui peuvent causer des dégats sporadiques, les phytophages vivant exclusivement aux dépens d'Eucalyptus spp. en Italie sont Phoracantha semipunctata, Gonipterus scutellatus et Ctenarytaina eucalypti. La première espèce est nuisible aux eucalyptus cultivès pour la production du bois et est répandue en Italie centrale et méridionale, en Sicile et en Sardaigne, alors que les deux autres espèces endommagent surtout les eucalyptus destinés aux marchés de fleurs (fleurs et rameaux) et ne sont prèsentes qu'en Ligurie occidentale. La lutte contre P. semipunctata est conduite par des interventions d'ordre sylvicultural, consistant essentiellement è recéper des peuplements sérieusement attaqués; le parasite oophage Patasson nitens, importé d'Afrique du Sud, permet de controler G. scutellatus alors que les larves de plusieurs syrphes prédatrices agissent efficacement contre C. eucalypti.  相似文献   
122.
Twenty stifles (10 dogs) were studied for a period of 1 year after various lesions of the cranial cruciate ligament and medial meniscus were produced surgicaoy. Through serial arthroscopic evaluations, degenerative processes In stifles with a "torn" cranial cruciate ligament were documented. Intra-articular changes were minimal after partial meniscectomy and were severe after total meniscectomy. Multiple arthroscopies caused no demonstrable changes.  相似文献   
123.
陈向新 《油气储运》1994,13(5):32-34
随着输气管道建设的发展,管道自身及其周围建筑物的安全保证问题,已引起人们高度重视,关于管道安全保证有两种指导思想:①距离安全保证模式,其设防原则是对管道自身强度有一定要求,主要通过控制不同压力,不同管径的管距建筑物的相应距离来保证管道及附近建筑物的安全;②强度安全保证模式,其设防原则是在管道设计,材料及设备选用,施工,检验,生产到更新改造的全过程中,对管道的强度和严密性有严格的要求,为管道系统及周  相似文献   
124.
A steam-dryer, designed and manufactured in Sweden, was evaluated for destroying Bursaphelenchus xylophilus in pine chips from southern USA. In a trial, pine chips were treated at different temperature and pressure regimes for 5 or 10min. The lowest time/temperature/pressure combination was to increase the vessel temperature from 85 to 104°C in 5 min at low pressure. Samples of pine chips were assayed for nematodes in laboratories in USA, Sweden, and Finland. No nematodes of any species were recovered from any of the treated pine-chip samples. Large and heterogeneous pieces of wood in the treated samples were also nematode-free. The apparatus was a prototype capable of handling about 400 kg h-1. The final version would have to be able to process 100-200 th-1.  相似文献   
125.
Antiserum to a partially purified neuraminidase fromPasteurella multocida, type A:3, was adsorbed with protease-digestedP. multocida type 3 lipopolysaccharide (LPS) to remove LPS immunoreactivity. The LPS-adsorbed antineuraminidase caused a 77% reduction in the neuraminidase activity of homologousP. multocida in anin vitro enzyme neutralization test. All 14 mice passively immunized with the adsorbed antineuraminidase were protected against challenge infection with homologousP. multocida in a mouse protection test. Ten out of 14 mice in one group that received antisera containing antibodies to both neuraminidase and LPS were protected. In contrast, only 1 out of 14 mice that were immunized with pre-immune serum survived the challenge. These results suggest that antiserum toP. multocida neuraminidase was, at least partly, responsible for the protection observed in this study. Neuraminidase may be one of the immunogenic protective proteins present in aqueous extracts ofPasteurella multocida.  相似文献   
126.
127.
Hyperchylomicronaemia was identified in a four-week-old Siamese kitten with lethargy, in-appetence, hindlimb ataxia and profound anaemia. The kitten was euthanased and at necropsy a thrombus was found occluding the caudal aorta. Two littermates later presented with lethargy, inappetence and hypertriglyceri-daemia which resolved after being weaned on to a low fat diet. A similar condition was subsequently diagnosed in a kitten born to the same sire but a different queen. The expression of hyperchylomicronaemia in two related litters was suggestive of an inherited, familial defect in the function of lipoprotein lipase (LPL). The activity of this enzyme was reduced in all three parents, the two recovered cases and two related, but apparently unaffected kittens, compared with a control group of unrelated cats belonging to the breeder. This reduction in activity was not attributable to defective activation of LPL by its serum cofactor apolipoprotein C-II or the presence in plasma of a factor that inhibited LPL. The gene that codes for LPL was examined by restriction fragment length polymorphism analysis using a human LPL cDNA probe. The results showed that the cat has a similar, but not identical, LPL gene to man. However, there were no differences in the restriction fragment patterns obtained from affected, unaffected and control animals.  相似文献   
128.
Provision of feed supplies for the rapidly growing livestock population is essential in West Asia. Shortages can be alleviated by growing forage crops in the existing fallow lands.
Narbon vetch (Vicia narbonensis L.) is a leguminous species with high yield potential, drought tolerance and cold resistance. It could be used for grain and straw production as source for animal feed in dry areas. It is good source of protein with seeds contain 28 % protein yielding 364 kg per hectare protein, whilst straw contains 9 % protein and yields a similar amounts of digestible protein per hectare.
Nine promising lines of Narbon vetch developed at ICARDA were tested at two sites over four years under rainfed conditions. Since climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment to give eight environments with annual rainfall varied from 195 to 504 mm.
Narbon vetch possessed high seedling vigour with rapid winter growth and negligible cold damage. Grain yield varied form 0.47 to 1.90 t/ha, with a harvest index varying from 30 to 40 %. The data indicated that below 300 mm rainfall the grain yield varied from 0.47 t/ha when rain fall was 195 mm to 1.4 t/ha when rainfall was 245 mm. Most of the lines had wide adaptation to dry areas in terms of both grain yield and stability. Climate, except early spring rains had little effect on biological and grain yields.  相似文献   
129.
Six out of eight different Trichomonas gallinae strains isolated from racing pigeons proved to be resistant to the nitroimidazole drugs ronidazole, carnidazole and metronidazole. The minimal cytocidal concentration of ronidazole was determined in in vitro experiments. Moreover, a therapeutic dose for ronidazole was determined for the control of trichomoniasis in pigeons from which the resistant T. gallinae strains were isolated. It was a 5-fold increase of the recommended ronidazole dosage which eliminated the infection in affected pigeons.  相似文献   
130.
The mineral forms of phosphorus in three urban sewage sludges were characterized using high-resolution solid-state phosphorus-31 nuclear magnetic resonance (NMR) coupled to a sequential extraction. The sludges studied were an anaerobically-digested and heat-treated sludge (Paris-Achères), an activated sludge (Briare) and an anaerobically-digested sludge (Nancy). NMR observations were conducted using both single-pulse and cross-polarization sequences in order to distinguish between 31P nuclei far from 1H nuclei, and 31P located within a fraction of a nanometre of 1H. This approach showed that a complex mixture of P species was present in these sludges. A mixture of hydrogenated octocalcium phosphates and apatites was observed in the three samples. Monetite was present in the anaerobically-digested sludge and brushite in the activated sludge. Dehydrogenated condensed calcium phosphates (compounds with a Ca:P ratio higher than 1.0 such as fluorapatite or tricalcium phosphate) and dehydrogenated pyrophosphates were also probably present in the anaerobically-digested sludge. A poorly-ordered wavellite was observed in the three sludges after the HCl extraction. However, results were inconclusive as to whether this mineral was present in the three sludges, or had been precipitated during the sequential extraction.  相似文献   
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