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71.
目的:分析艾司美拉唑治疗胃溃疡患者成本效果的影响因素。方法:回顾性分析2014年9月-2018年1月我院诊治的胃溃疡患者220例的临床病例资料,根据治疗药物的不同分为观察组120例与对照组100例,对照组给予奥美拉唑+克拉霉素+阿莫西林治疗,观察组给予艾司美拉唑+克拉霉素+阿莫西林,两组均持续治疗观察2周,对比两组治疗成本、治疗效果、不良反应的发生情况和成本效果,以及影响艾司美拉唑治疗胃溃疡患者成本效果的因素。结果:观察组与对照组患者完成治疗周期的成本费用分别为567.14±48.23元、551.49±45.61元,两组比较差异无统计学意义(P0.05)。观察组与对照组的治疗总有效率分别为95.83%(115/120)和82.00%(82/100),观察组显著高于对照组(P0.05)。观察组与对照组治疗期间的腹胀、便秘、恶心、口腔异味等不良反应发生率为8.33%(10/120)和11.00%(11/100),对比差异无统计学意义(P0.05)。观察组C/E与ΔC/E值均显著低于对照组(P0.05)。多因素logistic回归分析显示病程、溃疡直径、不良反应为影响艾司美拉唑治疗胃溃疡成本效果的主要因素(P0.05)。结论:艾司美拉唑治疗胃溃疡患者成本效果好,且不会增加不良反应的发生,病程、溃疡直径、不良反应为影响成本效果的主要因素。 相似文献
72.
73.
We examined the effect of two levels of soil pH (5 and 6) on the ability (effectiveness) of ectomycorrhizal fungi to increase the growth of Eucalyptus globulus Labill. at a deficient supply of P. Plants were inoculated with one of six fungal isolates [Laccaria laccata (Scop. ex Fr.) Berk. and Br. (isolates A and B), Pisolithus tinctorius (Pers.) Coker and Couch (isolates A and B), Descolea maculata Bough. and Mal. and Setchelliogaster sp. nov.] and were grown in a P-deficient sand, in pots, in a temperature-controlled glasshouse. Seedlings were harvested 89 days after planting and were assessed for dry matter production, tissue P concentrations, ectomycorrhizal colonization of roots and hyphal development in soil.Uninoculated plants had less than 5% of their fine root length colonized by ectomycorrhizal fungi. In contrast, inoculated plants had 30% or greater of their fine root length ectomycorrhizal. Inoculation increased the uptake of P and growth of plants for all isolates and at both levels of soil pH, although growth responses to inoculation were greater at pH 6, particularly for the two L. laccata isolates. Isolates which colonized roots most extensively increased plant growth to the greatest extent. D. maculata was the most effective fungal isolate at pH 5, and both D. maculata and L. laccata A were most effective at pH 6. The effects of soil pH on plant growth were also related to some extent to the effects of soil pH on colonized root length. Growth responses to inoculation were related less well to hyphal development in soil. The L. laccata isolates formed more hyphae in soil (on a per pot, per m of fine root, and per m of colonized fine root basis) than other fungal isolates, but were not always more effective in increasing plant grown. 相似文献
74.
A greenhouse study was undertaken to determine the nitrogen and phosphorus fertilization requirements for raising mycorrhizal seedlings in soil in containers. Seedlings of Leucaena leucocephala were grown for 40 days in dibble tubes containing fumigated or nonfumigated soil uninoculated or inoculated with Glomus aggregatum. The soil was fertilized with NH4NO3 solution to obtain 25–200 mg N kg-1 soil, and with a KH2PO4 solution to establish target soil solution P concentrations of 0.015–0.08 mg P l-1. At the end of 40 days, seedlings were transplanted into pots containing 5-kg portions of fumigated soil. Posttransplant vesicular arbuscular mycorrhizal fungal (VAMF) effectiveness, measured as pinnule P content, plant height, shoot dry weight and tissue N and P concentrations, was significantly increased by pretransplant VAMF colonization in both soils. The best posttransplant mycorrhizal colonization and mycorrhizal growth responses were observed if the nonfumigated pretransplant soil was amended with 50 mg N kg-1 soil and 0.04 mg P l-1 or if the fumigated pretransplant soil was amended with 100 mg N kg-1 soil and 0.04 mg P 1-1. There was no relationship between NP ratios of nutrients added to the pretransplant soil medium and shoot NP ratios observed after transplanting. Shoot NP ratio was also not correlated with root colonization level.Contribution from the Hawaii Institute of Tropical Agriculture and Human Resources Journal Series No. 4025 相似文献
75.
Glomus aggregatum and Leucaena leucocephala were interacted in an acid Mn-rich oxisol unamended or amended with lime [Ca(OH)2] or gypsum (CaSO4) at soil P concentrations considered optimal for mycorrhizal host growth and sufficient for mycorrhiza-free growth. At 0.02 mg P 1-1, both vesicular-arbuscular mycorrhizal fungal (VAMF) colonization and function were significantly curtailed if soil was not amended with gypsum or lime. The highest mycorrhizal effect was observed in the limed soil, followed by the soil treated with gypsum at the rate of 32 g Ca kg-1 soil. Higher concentrations of gypsum deleteriously affected VAMF infectivity and effectivity. The first increment of gypsum compensated completely for the VAMF colonization and for part of the mycorrhizal effect that was lost due to low pH. The superiority of the limed soil to that amended with gypsum apparently lies in the fact that Ca supply was assured in the former and also that the adverse effects of toxic constituents such as H+ and Mn2+ were eliminated. We were unable to separate the effect of Ca on VAMF from its effect on the host because a P concentration sufficient for mycorrhiza-free growth was not attained due to interaction of some of the P with Ca to form insoluble phosphate.Contribution from the Hawaii Institute of Tropical Agriculture and Human Resources Journal Series No. 4045 相似文献
76.
灭虫精的杀虫活性及田间防治褐飞虱的应用研究 总被引:13,自引:1,他引:12
灭虫精(Imidacloprid通用名称吡虫啉)系一种内吸性杀虫剂,属硝基亚甲基化合物,对稻飞虱具有极强的生物活性。室内测定褐飞虱付Nilapavarta lugens Stal 3龄与5龄若虫LD50值分别为2.55x10-5μ/头与6.78x10-5μg/头,其毒力回归方程分别为Y=r5.6231+1,0486X和Y=5.2091+1.2389X。实验表明,该药具有极好的触杀和胃毒作用,稻田应用的有效剂量为15~30g/hm2,是扑虱灵常规用量的1/5~1/10。田间药效特征突出地表现为速效(1-3d)、持效(4-10d)和残效(11d以上)的三段效应,90%以上的防治效果可维持在40d以上.试验还表明,灭虫精田间应用表现出在飞虱和天敌之间的良好选择性,对稻田益蛛基本无害,是一种很有前途的稻田应用杀虫剂。 相似文献
77.
Elena L. Zvereva Mikhail V. Kozlov Nathan E. Rank 《Biological journal of the Linnean Society. Linnean Society of London》2016,119(1):201-212
Generalist predators are frequently seen as evolutionary forces that narrow the host range in herbivorous insects. Predators may favour specialization of herbivores on host plants containing toxic chemicals (which can be used by herbivores for their own defence) if host plant‐derived defences provide better protection from enemies than do autogenously produced defences. We compared the effectiveness of these two defensive strategies in the larvae of six species of leaf beetle (Chrysomelidae) against wood ants (Formica rufa group) in field experiments. Ants were more strongly repelled by larvae with host plant‐derived, salicylaldehyde‐containing secretions than by larvae with various autogenous secretions, but collectively foraging ants ultimately overcame any type of chemical defence by social interactions, chemical signalling, and olfactory learning. As a result, ants killed all larvae of Chrysomela lapponica defended by salicylaldehyde‐containing secretions within 2 days of their introduction to willows within 15 m of ant nests. We conclude that in the field neither type of chemical defence provides complete protection against wood ants in the vicinity of their nests, and that evolutionary shifts from autogenous production of secretion to sequestration of plant allelochemicals in leaf beetles may be favoured mostly at low ant densities on the periphery of ant foraging areas. 相似文献
78.
The potential significance of nectar‐feeding bats as pollinators in mangrove habitats of Peninsular Malaysia 下载免费PDF全文
We tested the hypothesis that bats are effective pollinators of mangroves in Malaysia. Bats (Eonycteris spelaea) visited flowers of two Sonneratia species frequently, and deposited large quantities of conspecific pollen grains on stigmas. The bats are likely to be important pollinators of the two mangrove species. 相似文献
79.
The role of natural regeneration to ecosystem services provision and habitat availability: a case study in the Brazilian Atlantic Forest 下载免费PDF全文
Bernardo B. N. Strassburg Felipe S. M. Barros Renato Crouzeilles Alvaro Iribarrem Juliana Silveira dos Santos Daniel Silva Jerônimo B. B. Sansevero Helena N. Alves‐Pinto Rafael Feltran‐Barbieri Agnieszka E. Latawiec 《Biotropica》2016,48(6):890-899
Natural regeneration provides multiple benefits to nature and human societies, and can play a major role in global and national restoration targets. However, these benefits are context specific and impacted by both biophysical and socioeconomic heterogeneity across landscapes. Here, we investigate the benefits of natural regeneration for climate change mitigation, sediment retention and biodiversity conservation in a spatially explicit way at very high resolution for a region within the global biodiversity hotspot of the Atlantic Forest. We classified current land‐use cover in the region and simulated a natural regeneration scenario in abandoned pasturelands, areas where potential conflicts with agricultural production would be minimized and where some early stage regeneration is already occurring. We then modeled changes in biophysical functions for climate change mitigation and sediment retention, and performed an economic valuation of both ecosystem services. We also modeled how land‐use changes affect habitat availability for species. We found that natural regeneration can provide significant ecological and social benefits. Economic values of climate change mitigation and sediment retention alone could completely compensate for the opportunity costs of agricultural production over 20 yr. Habitat availability is improved for three species with different dispersal abilities, although by different magnitudes. Improving the understanding of how costs and benefits of natural regeneration are distributed can be useful to design incentive structures that bring farmers’ decision making more in line with societal benefits. This alignment is crucial for natural regeneration to fulfill its potential as a large‐scale solution for pressing local and global environmental challenges. 相似文献
80.
The on-going loss of biodiversity calls for assessing the performance of conservation strategies. In the case of marine protected areas (MPAs), a common indicator of success is the amount of biodiversity protected within them. However, there are many cases where the information for the official MPA boundary is not available, making it difficult to precisely measure the indicator. A solution to this problem is to create circular buffers around the centre location of MPAs for which boundaries are missing, equivalent in area to that reported officially for the MPA. The Coral Triangle Atlas provides the opportunity to quantify more precisely the validity of using buffers as proxies for MPA boundaries both at national and regional scales in the Coral Triangle. We used 612 existing MPA boundaries, converted them into point data at their centroids and then created circular buffers of area equal to that of the MPAs’ original polygons. Errors in estimated area of protected coral reefs were used to measure the bias created by the centroid buffers. We obtained an underestimation of protected coral reef area, both at the scale of the Coral Triangle region and at a national scale when using centroid buffers, with a larger underestimation as more MPA boundary proxies were used. We found that the size of MPA does not have a significant effect on the percentage of bias when MPAs are smaller than 100 km2 at a national level, and smaller than 1000 km2 at a regional level. With less than 15% of the total MPAs in the CT region larger than 100 km2, these results suggest that using buffers at a national scale for small MPAs may be a good solution to missing boundaries and cheaper than trying to collect exact information if working at a national or multinational scale. However, for countries with large MPAs such as Indonesia, using this proxy system will tend to create a larger error. At a regional scale, such as the Coral Triangle region, an estimation of total protected coral reef using buffers as MPA boundaries proxies will produce a small underestimation, thus, producing conservative results of protected coral reef area. This study shows the importance of assessing the bias introduced by using proxies for MPA boundaries when measuring indicators of conservation target achievement for coastal and marine areas. 相似文献