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41.
1 The composition of pome fruit orchard inhabiting spider assemblages was investigated at different geographical scales (Holarctic, European, inter- and intraregional levels within Hungary) using previous faunistic studies and data collected in Hungary between 1995 and 1997. Samples in Hungary were taken from the canopy and herb layer of apple and pear orchards in five markedly different fruit-growing regions by beating and sweep-netting methods. 2 The composition of canopy spider assemblages of apple orchards was analysed for the Holartic region and found to be determined by latitude at family level, and by the main zoogoegraphical regions at genus level. At the European scale, both the genus and species composition changed along a north–south gradient. 3 A comparison among apple and pear orchards located in different regions in Hungary, showed that both foliage- and grass-dwelling spider assemblages varied considerably in species composition and dominance order. 4 Within the same region, both the foliage- and grass-dwelling spider assemblages showed moderate differences in apple and pear orchards submitted to different treatments. Although the assemblages of spiders inhabiting the canopy and the herbaceous layer can be unambiguously distinguished, some overlap still occurs. 5 We conclude that the composition of spider assemblages is basically determined by geographical location. Although both pesticide treatments and available prey densities can influence the population of spiders, such factors are of moderate importance when compared with the effect of regionality, even when considered at smaller scale. However, most members of the family Theridiidae and the large orb-weavers (Araneidae) decreased considerably in treated plots. Scale-specific differences are thus relevant in determining the composition of prey–predator systems in orchards, and should be taken into account when designing integrated pest management (IPM) programs for apple and pear orchards. 相似文献
42.
In a study of the use of a digoxin assay service and its influence on clinical management 285 assay requests were audited over 12 weeks. For 67 (24%) there was no clear clinical indication for the request and for 140 the period between the last dose of digoxin being given and the blood sample being taken was either unknown or inappropriate. Treatment in 64 patients (22%) was changed after the assay result was received [corrected]. 24 of these changes bore no relation to the original clinical indication for requesting the assay, suggesting that such changes were based on the assay result alone. Of samples collected within six hours after the last dose, 15 of 69 (22%) led to a reduction in treatment compared with 10 of 116 (9%) taken after six hours (p less than 0.025), thereby highlighting the danger that incorrectly timed samples may lead to inappropriate clinical decisions. 相似文献
43.
Starved houseflies were held over a suspension of Aujeszky's virus (PRV-1) for 24-48 h. One group was rinsed in 70% ethanol to kill virus attached to the body surface. No virus was isolated from this group. For the other group the titre of virus decreased more rapidly on the body surface of flies than in the environment. Model experiments demonstrated that the Aujeszky's virus cannot survive in the body of the housefly but the body surface may be contaminated for a period of time depending on the initial viral titre. Experiments showed that susceptible pigs fed on flies contaminated with Aujeszky's virus may become infected. The quantity of virus (5 x 10(5) pfu ml-1) shed by a single housefly during biting and vomiting on the cornea or abraded skin proved to be sufficient to cause infection in susceptible pigs, rabbits and a lamb. It is possible that houseflies could play a role in transmission of infection within herds. Transmission between herds is much less likely. 相似文献
44.
M.J. Parnham S. Shoshan H. Schoenmaker I.L. Bonta 《Prostaglandins & other lipid mediators》1982,23(1):85-98
Local administration of PGE2 (2 μg) to polyether sponges, implanted s.c. in rats, inhibited hydroxyproline and total protein accumulation, without altering relative amounts of collagen, when administered early during granuloma development. In contrast, while DNA as well as total protein accumulation was inhibited by local PGE2 treatment of established granuloma, hydroxyproline accumulation and the relative amounts of collagen were enhanced. This PGE2-induced collagen enhancement was associated with an increased type III : type I collagen ratio, possibly due to differential intracellular breakdown of newly synthesized collagen. The solubility of granuloma collagen was unaffected by PGE2. Impregnation of sponges with carrageenan before implantation, thereby giving macrophage-dominated granuloma, did not affect the changes in protein and DNA induced by later treatment with PGE2, but did reverse the PGE2-induced accumulation of hydroxyproline. This latter effect probably reflects macrophage-mediated, PGE2 enhancement of collagenolytic activity. 相似文献
45.
Lúcia de Paula Célio L Silva Daniela Carlos Camila Matias-Peres Carlos A Sorgi Edson G Soares Patrícia RM Souza Carlos RZ Bladés Fábio CS Galleti Vânia LD Bonato Eduardo DC Gonçalves Érika VG Silva Lúcia H Faccioli 《Genetic vaccines and therapy》2007,5(1):1-7
The great challenges for researchers working in the field of vaccinology are optimizing DNA vaccines for use in humans or large animals and creating effective single-dose vaccines using appropriated controlled delivery systems. Plasmid DNA encoding the heat-shock protein 65 (hsp65) (DNAhsp65) has been shown to induce protective and therapeutic immune responses in a murine model of tuberculosis (TB). Despite the success of naked DNAhsp65-based vaccine to protect mice against TB, it requires multiple doses of high amounts of DNA for effective immunization. In order to optimize this DNA vaccine and simplify the vaccination schedule, we coencapsulated DNAhsp65 and the adjuvant trehalose dimycolate (TDM) into biodegradable poly (DL-lactide-co-glycolide) (PLGA) microspheres for a single dose administration. Moreover, a single-shot prime-boost vaccine formulation based on a mixture of two different PLGA microspheres, presenting faster and slower release of, respectively, DNAhsp65 and the recombinant hsp65 protein was also developed. These formulations were tested in mice as well as in guinea pigs by comparison with the efficacy and toxicity induced by the naked DNA preparation or BCG. The single-shot prime-boost formulation clearly presented good efficacy and diminished lung pathology in both mice and guinea pigs. 相似文献
46.
CS Ortiz 《Biotechnic & histochemistry》2014,89(2):121-125
A simple low pressure liquid chromatographic method is reported that can separate the basic fuchsine homologues, rosaniline, magenta II and new fuchsine from an impure commercial dye. The chromatographic purity of the separated dyes is > 90%. All homologues were obtained in multi-milligram amounts per chromatographic run; precise yields depend on the composition of the starting material and potentially may be greater. This is a useful preparative procedure for generating chromatographically pure samples of basic fuchsine homologues, especially those that cannot be obtained in pure form by direct synthesis. 相似文献
47.
The water quality of the Siluko River, Edo State, Nigeria was investigated from March to August 2015 to determine its suitability for drinking and usage for domestic purposes. Water samples collected from three stations were tested for thirteen physico-chemical parameters using standard analytical procedures. Temperature, phosphate and chloride were significantly different across the three stations. All other parameters, with the exception of turbidity, dissolved oxygen and phosphate, were within the permissible limits recommended by the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO). Water Quality Index (WQI) values ranged from 11.24 to 16.15, indicating excellent water quality. While the quality of the water from the Siluko River is suitable for drinking and domestic usage, to prevent future deterioration of the water, it is recommended that the regulating authorities monitor effluents discharged into the river from human activities. 相似文献
48.
Guohao?HeEmail author Ronghua?Meng Melanie?Newman Guoqing?Gao Roy?N?Pittman CS?Prakash 《BMC plant biology》2003,3(1):3
Background
Genomic research of cultivated peanut has lagged behind other crop species because of the paucity of polymorphic DNA markers found in this crop. It is necessary to identify additional DNA markers for further genetic research in peanut. 相似文献49.
Phospholipase D (PLD) is an enzyme which participates in the signalling mechanism cleaving phosphatidylcholine (PC) to choline and phosphatidic acid (PA). In Tetrahymena pyriformis GL this enzyme activity is enhanced by different kinds of agonists (sodium orthovanadate, sodium fluoride and phorbol 12-myristate 13-acetate), and its activity can be inhibited by inhibitors such as pertussis toxin, calphostin C, genistein, trifluoperazine. These results suggest that the PLD signalling pathway is connected with the tyrosine kinase, phospholipase C, phosphatidylinositol and G-protein coupled signalling pathways. By demonstrating the PLD activity in Tetrahymena our knowledge on the signalling mechanisms at a unicellular level has been extended. The results support our view that most transducing mechanisms that are characteristic of mammalian cells are also in the protozoan Tetrahymena. © 1997 John Wiley & Sons, Ltd. 相似文献
50.
Chilamakuri CS Reddy Khader Shameer Bernard O Offmann Ramanathan Sowdhamini 《BMC bioinformatics》2008,9(1):281