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41.
目的:探讨长半衰期药物(t1/2〉24h)在无清洗期时生物等效性研究中的AUC和Cmax的计算,通过无清洗期的实验数据推算出正常清洗期的数据。方法:利用SPSS软件,建立二室模型口服药物在无清洗期时的半衰期为100小时的生物等效性模型,通过优化AUC和Cmax的计算方法,降低药物残留对第二周期药物浓度的影响,进而增加AUC和Cmax的计算的精确性,最后用较精确的方法推算出正常清洗期的AUC和Cmax,利用精确的数据进行生物等效性的进一步验证。结果:在无清洗期的状态下,取样时间在大于0.8个半衰期时,平均值法计算的Auc和Cmax的结果误差小于5%,变异系数小于25%,较为精确,生物等效性研究进一步验证了这一观点。结论:在无清洗期的情况下,生物等效性研究最小的采样时间为0.8个半衰期。 相似文献
42.
Ignacy Kitowski 《Journal of Ethology》2005,23(1):3-8
Play bouts and active training of juveniles by Montagus harrier (Circus pygargus) adults in the post-fledging period were observed. Fledglings often played with prey and with a variety of inanimate objects such as bits of moss, regurgitated pellets, sticks and a wad of hay. Inanimate objects selected for play were, in length, very similar to the common vole (Microtus arvalis), which is the most common prey of the species during their breeding period. Some recently fledged individuals were trained to capture invertebrate prey by adults demonstrating techniques for the fledglings and thus develop their hunting skills. Training sessions took place only in the foraging areas of the adult birds. 相似文献
43.
JOCHEN BECKER CHRISTIAN ORTMANN MARKUS A. WETZEL CAROLA WINKELMANN JOCHEN H. E. KOOP 《Freshwater Biology》2013,58(2):372-381
1. We assessed sex‐specific seasonal changes in major energy storage compounds (triglycerides, glycogen) in Gammarus fossarum and Gammarus pulex collected from the field, with respect to their reproductive activity. 2. The dynamics of stored energy followed a seasonal pattern in both species and sexes. Moreover, over a 4‐year period, these changes were independent of the year in which they were investigated. Stored energy reached a peak in late winter, but was depleted in late summer and early autumn, coinciding with the reproductive periods. 3. Triglyceride (annual mean ± SD) accounted for 79.7 ± 11.9% of the total stored energy and was responsible for the seasonal pattern. In contrast, glycogen contributed a lesser percentage (20.3 ± 11.9%). Over the study period, the amount of stored energy ranged between 0.39 and 4.08 kJ g?1 dry mass (triglyceride: 0.19–3.69 kJ g?1 dry mass; glycogen: 0.14–0.80 kJ g?1 dry mass). 4. In both species, the energy reserves of males were drastically depleted shortly before the cessation of precopulatory mate guarding in the field, thus offering a bioenergetic explanation for the reproductive period in these two widespread species. 相似文献
44.
Dorthe L. Hansen Henrik F. Brødsgaard Annie Enkegaard 《Entomologia Experimentalis et Applicata》1999,93(3):267-273
The life table characteristics of the polyphagous mirid Macrolophus caliginosus Wagner (Heteroptera: Miridae) preying on various stages of Tetranychus urticae Koch (Acari: Tetranychidae) with tomato as host plant were described at 22 °C. The following average parameters were obtained: Female longevity: 28.7 days; fecundity: 0.7 eggs/female/day; egg mortality: 2.6%; pre-oviposition period: 5.5 days; oviposition period: 18.1 days; post-oviposition period: 3.2 days; juvenile development time: 26.8 days; juvenile mortality: 34.9%; and sex ratio (/(+): 0.46. Life table parameters were estimated as net reproduction rate (R
0): 6.15; intrinsic rate of increase (r
m): 0.031 day–1; finite rate of increase (): 1.032; mean generation time (T
c): 58.17 days; and doubling time (T
2) 22.2 days. The parameters obtained were in accordance with those reported for M. caliginosus fed on another mite species (T. turkestani Ugarov & Nikolski (Acari: Tetranychidae)). However, compared to the performance of M. caliginosus fed on common glasshouse insect pests, a diet consisting of only mites appeared to be inferior. However, being a voracious predator, M. caliginosus may be a valuable addition to existing methods of mite control. 相似文献
45.
Spruce beetle populations (Dendroctonus rufipennis) (Coleoptera: Scolytinae) in Engelmann spruce (Picea engelmannii) stands were monitored at twelve sites for 6 years in northern Colorado using pheromone‐baited Lindgren funnel traps. During the trapping period, over 30,000 beetles were captured, and beetle abundance data were used to construct empirical models of trap capture phenology based on day of year, accumulation of thermal units and thermal day thresholds, with the goal of informing future regional trapping efforts and producing a simple model for use by forest managers. Ordinal day models outperformed thermal accumulation and thermal threshold models in both predictive power and parsimony. Mean date of earliest capture was Day 153 (June 2) and ranged from Day 126 to Day 161 (May 6–June 10), and mean date of final capture was Day 243 (August 31) and ranged from Day 220 to Day 286 (August 8–October 13). A two‐parameter logistic function was the most parsimonious of several ordinal day models, accounting for 81% of the variance in cumulative trap capture across all sites and dates. The model predicts 50% of trap captures to occur by Day 181 (June 30). This model has application as a decision support tool for forest ecosystem managers concerned with the timing of trap deployment or D. rufipennis mitigation treatments. 相似文献
46.
福建平潭岛海岸不同演化阶段草丛沙堆表面老鼠艻叶水势日变化特征 总被引:1,自引:0,他引:1
以福建省平潭岛海岸不同演化阶段草丛沙堆表面典型沙生植物老鼠艻为对象,研究其叶水势日变化特征及其影响因素.结果表明: 老鼠艻叶水势日变化以“W”型为主,午间出现短暂升高现象.发育阶段沙堆表面老鼠艻叶水势日均值较稳定阶段高,且夜间水分恢复能力更强;老鼠艻叶水势与大气水势和相对湿度呈显著正相关,与气温呈显著负相关,但与不同深度土壤水势无显著相关性;发育阶段沙堆丘间地老鼠艻叶水势在10:00—16:00皆高于迎风坡和背风坡,迎风坡除10:00和12:00外皆低于背风坡.不同坡位叶水势日变异程度表现为背风坡>迎风坡>丘间地,但无显著差异.沙堆迎风坡老鼠艻叶水势与大气水势和相对湿度呈显著正相关,与气温呈显著负相关;沙堆背风坡和丘间地老鼠艻叶水势与气象因子有一定相关性,但不显著. 相似文献
47.
Midori Tuda 《Population Ecology》1996,38(2):133-140
The effects of spatial structure in terms of local capacity, or the maximum number of larvae surviving competition at resource patches, and temporal structure in terms of the period vulnerable to parasitoid attack in host populations on the persistence of host-parasitoid systems were quantitatively evaluated by laboratory experiments and well-parameterized model analyses. One of two bruchid beetles,Callosobruchus maculatus andC. phaseoli, were used as a host with Heterospilus prosopidis used as the parasitoid.C. maculatus, in which few larvae survive competition to become adults in each bean, andC. phaseoli, in which many larvae become adults in each bean, along with two kinds of beans, the mung and the azuki, were combined to construct four (2×2) resource-herbivorous host-parasitoid systems that differed in local capacity and vulnerable period. The mung-C. maculatus system with the parasitoid was the most persistent, i.e., took the longest time for extinction of either the host or parasitoid to occur. Since this resource-herbivorous host combination exhibited the lowest local capacity and the shortest vulnerable period, these two conditions possibly promoted the persistence of the system. A model incorporating the host population structure supported the observed persistence. Furthermore, the possible contribution of the timing of density-dependent competition of the host on the host-parasitoid persistence is predicted. 相似文献
48.
在21℃饲养的粘虫雌蛾腺体提取物中Zll-16:Aid含量峰值时间是羽化后第8~9天;25℃是羽化后第4~5天,27℃是羽化后第3~4天。低温不仅推迟了粘虫雌蛾求偶和释放性信息素的时间,而且降低了腺体中性信息素的滴度。在27℃,粘虫雌蛾腺体中Zll-16:Ald峰值的平均值达15ng;在25℃时为10ng,而在21℃时,只有5ng。由此可见,低温环境明显抑制粘虫雌蛾的性发育,延缓了性成熟。 相似文献
49.
Zaida Tárano Eloisa Fuenmayor 《Ethology : formerly Zeitschrift fur Tierpsychologie》2014,120(4):313-323
We simulated the presence of an acoustic competitor by broadcasting conspecific playbacks to males of Johnstone's whistling frog, Eleutherodactylus johnstonei, in the field. We broadcast calls that differed in duration (short, typical, and long), dominant frequency (high, typical, and low), and period (short, typical, and long), and analyzed male vocal responses. We tested the hypothesis that males respond by escalating vocally when they are exposed to female‐attractive calls and by ignoring unattractive ones. At the population level, males responded to playbacks in ways that would potentially increase their attractiveness with regard to solo calling: males increased the duration, reduced the dominant frequency, and increased their calling effort (duty cycle), despite an increase in call period. The modification of call duration occurred only in response to playbacks of low‐frequency calls, long calls, and short‐period calls (selective response), while the modification of the dominant frequency was independent of the characteristic of the playback (fixed response). Contrary to the expected, males did not reduce the call period when they were exposed to attractive playbacks. At the ultimate level, the results suggest energy‐saving strategies. In addition, males seem to trade off call period for the avoidance of acoustic interference with attractive calls as calling effort was typically increased by increasing call duration but only rarely by reducing the call period. Interactive playbacks are necessary to better understand the calling strategies of males of E. johnstonei. 相似文献
50.