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951.
Orius strigicollis (Poppius) was reared on the modification of rearing media for Tetrastichus sp. at 28°C, 18L: 6D, and 50‐60% RH, in which meat diets were used for partial replacements of insect source of the artificial diets. Life history traits of the predacious bug fed on the diet were measured. Nymphal development period and mortality rate of O. strigicollis were about 14 days and 31.5% (survival rate: 68.5%), respectively. The female bug produced average of 82.5 eggs during its oviposition period of 18 days when artificial oviposition substrate was provided. The fecundity was shown to be superior compared with previous researches on the species fed natural preys as a food. 相似文献
952.
Thuy Yen Duong Kim T. Scribner Patrick S. Forsythe James A. Crossman Edward A. Baker 《Molecular ecology》2013,22(5):1282-1294
Quantifying interannual variation in effective adult breeding number (Nb) and relationships between Nb, effective population size (Ne), adult census size (N) and population demographic characteristics are important to predict genetic changes in populations of conservation concern. Such relationships are rarely available for long‐lived iteroparous species like lake sturgeon (Acipenser fulvescens). We estimated annual Nb and generational Ne using genotypes from 12 microsatellite loci for lake sturgeon adults (n = 796) captured during ten spawning seasons and offspring (n = 3925) collected during larval dispersal in a closed population over 8 years. Inbreeding and variance Nb estimated using mean and variance in individual reproductive success derived from genetically identified parentage and using linkage disequilibrium (LD) were similar within and among years (interannual range of Nb across estimators: 41–205). Variance in reproductive success and unequal sex ratios reduced Nb relative to N on average 36.8% and 16.3%, respectively. Interannual variation in Nb/N ratios (0.27–0.86) resulted from stable N and low standardized variance in reproductive success due to high proportions of adults breeding and the species' polygamous mating system, despite a 40‐fold difference in annual larval production across years (437–16 417). Results indicated environmental conditions and features of the species' reproductive ecology interact to affect demographic parameters and Nb/N. Estimates of Ne based on three single‐sample estimators, including LD, approximate Bayesian computation and sibship assignment, were similar to annual estimates of Nb. Findings have important implications concerning applications of genetic monitoring in conservation planning for lake sturgeon and other species with similar life histories and mating systems. 相似文献
953.
Saadat M 《Biochemical and biophysical research communications》2004,324(2):584-587
In order to find the effect of genetic polymorphisms of glutathione S-transferase M1 (GSTM1) and GSTT1 on hematological changes of individuals chronically exposed to natural sour gas, the present study was done. Study subjects (59 males, 55 females) were residents of contaminated areas of Masjid-i-Sulaiman (southwest of Iran). The GSTM1 and GSTT1 genotypes were determined using a polymerase chain reaction-based method. The multiple linear regression method was applied. There is significant association between GSTs genotypes and either hemoglobin (t=2.185, P=0.031) or hematocrit (t=2.454, P=0.016). Also there is weak association between GSTs genotypes and WBC counts (t=1.802, P=0.074). The hemoglobin and hematocrit levels and WBC counts increased in individuals who had null genotypes of GSTM1 and GSTT1 compared to subjects with one or two active genes. Also the levels of hemoglobin and hematocrit and WBC counts increased in persons with one active genotype compared to subjects who had two active genes. There is no significant association between neither platelet nor WBC differential parameters and GSTs genotypes. 相似文献
954.
Cogun HY Fırat O Fırat O Yüzereroǧlu TA Gök G Kargin F Kötemen Y 《Journal of biochemical and molecular toxicology》2012,26(3):117-122
In this study, to identify mercury (Hg) toxicity and whether selenium (Se) has any role in alleviation of this toxicity, it was investigated the changes in hematological and serum biochemical parameters of Oreochromis niloticus. Fish were exposed to 0.01 and 0.1 mg/L Hg and 0.01 mg/L Hg + 0.1 mg/L Se and 0.1 mg/L Hg + 1.0 mg/L Se for 7 and 14 days. The exposure of O. niloticus to Hg alone resulted in decreases in red blood cell, white blood cell, hemoglobin, hematocrit values, and cholinesterase activity while it increased in alanine aminotransferase and aspartate aminotransferase activities and cortisol and glucose levels. Se, in combination with Hg, partially or totally caused an alleviation for the toxic effect of Hg on the above mentioned hematological and biochemical parameters. The results of our study showed that Se has a protective effect against toxicity induced by Hg. 相似文献
955.
水肥运筹对小麦旗叶光合特性及产量的影响 总被引:25,自引:7,他引:25
研究了不同灌水次数及等氮量不同施氮方式对优质强筋小麦品种郑麦9023旗叶净光合速率(Pn)、叶绿素荧光参数等光合性能及产量的影响。结果表明,旗叶Pn、PSⅡ的潜在活性(Fv/Fo)、PSⅡ的光化学最大效率(Fv/Fm)、光化学猝灭系数(qP)、非光化学猝灭系数(qN)及产量在不同灌水次数间的差异均达到显著或极显著水平,其中不灌水处理与灌水处理间的差异较大;在不同施氮处理问,氮肥全部基施与返青期追施(占40%)处理间植株旗叶的Pn、Fv/Fo、Fv/Fm、qP和qN差异不大,但两处理的上述光合参数及产量均明显低于拔节期或孕穗期追施(40%)处理,表明拔节期或孕穗期追施氮肥有助于减缓旗叶光合功能的衰退,延长叶片功能期,提高植株的光合产物积累。研究结果还表明,水、氮运筹对Pn、叶绿素荧光参数及产量性状的调控存在显著的互作效应,其中以灌拔节水 孕穗水并于孕穗期追施氮肥(W2N4)处理组合表现最好。 相似文献
956.
Steady states of a continuous culture with an inhibitory substrate were used to estimate kinetic parameters under substrate limitation (chemostat operation). Pure cultures of an indigenous Pseudomonas aeruginosa were grown in continuous culture on phenol, the sole source of carbon and energy, at dilution rates of 0.010 to 0.20 h- 1. Using different dilution rates, several steady states were investigated and the specific phenol consumption rates were calculated. In addition, phenol degradation was investigated by increasing the dilution rate above the critical dilution rate (washout cultivation). The results showed that the specific phenol consumption rate increased with increased dilution rate at steady state and that the degradation by Pseudomonas aeruginosa can be described by simple substrate inhibition kinetics under substrate limitation but cannot be described by simple substrate inhibition kinetics under washout cultivation. Fitting of the steady-state data from continuous cultivation to various inhibition models resulted in the best fit for the Yano and Koga kinetic inhibition model. The rs max value of 0.278 mg/mg/h obtained from the Yano and Koga equation was comparable to the experimentally calculated rs max value of 0.283 mg/mg/h obtained under washout cultivation. 相似文献
957.
Forty newly hatched unsexed Japanese quail (Coturnix coturnix japonica) chicks were fed diets containing 3 ppm aflatoxin (AF) and 4 ppm T2 toxin either singly and in combination for 35 days. Sera samples were collected from six birds in each group at the end of
the trial to study the effect of certain serum biochemical parameters. Highly significant (P < 0.01) differences were observed for serum total protein, albumin, globulin, glucose, cholesterol, aspartate transaminase
(AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transferase (GGT) between control and toxin
treated groups. Toxin treated groups did not reveal any significant difference for serum urea nitrogen, creatinine, uric acid,
calcium, phosphorus, sodium and potassium. There was a reduction in the levels of serum total protein, albumin, globulin,
glucose, cholesterol, ALT and elevation of AST and GGT and variable ALP levels observed in toxin treated groups.
Forms part of M.V.Sc. thesis of first author approved by the Tamil Nadu Veterinary and Animal Sciences University, Chennai
600 051, India. 相似文献
958.
Growth parameters and cadmium accumulation were investigated in alfalfa seedlings treated with 10 μM salicylic acid (SA) at
the beginning of seed imbibition. Shoot and root growths were accelerated by SA treatment and suppressed by Cd both in presence
and absence of SA. Cd accumulation was stimulated by SA in alfalfa seedlings in dependence of the treatment duration. K, Mg,
Ca and Fe contents in roots are decreased in the presence of Cd alone, while SA induces a decrease of Mg, Ca and Fe. Shoot
K, Mg and Ca concentrations are increased by Cd only in the absence of SA, while SA induces also an increase of these concentrations,
but only in the absence of Cd. High negative correlation of Cd concentration with K and Ca concentrations in root indicates
a competition for the same carrier not regulated by SA. Positive correlation between Cd and Mg concentrations in shoots, which
is decreased by SA pre-treatment, together with the increase of positive correlation between Cd and Fe concentrations in shoots
under the influence of SA, indicates a possible mechanism of SA action through maintenance of ionic homeostasis. 相似文献
959.
槐定碱与牛血清白蛋白的相互作用研究 总被引:1,自引:0,他引:1
在模拟动物体生理条件下,用荧光猝灭、荧光偏振和紫外-可见吸收光谱法研究了槐定碱与牛血清白蛋白(BSA)结合作用。荧光猝灭数据显示,槐定碱与BSA发生反应生成了新的复合物,属于静态荧光猝灭。求出了不同温度(19、25、31、37℃)下槐定碱与BSA作用的结合常数分别为1.219×106,1.164×106,1.110×106和1.057×106L/mol,由van’tHoff方程式计算槐定碱与BSA反应的热力学参数:焓变ΔH和熵变ΔS值分别为-5.97kJ/mol和96.11J/(mol.K),表明槐定碱与BSA间的作用力以静电引力为主。以华法林和布洛芬(分别为siteI和siteII探针)为标记药物研究槐定碱在BSA上的结合位点,结果表明,槐定碱结合在BSA疏水空腔的siteI位点。 相似文献
960.
Mathews DH 《Journal of molecular biology》2006,359(3):526-532
RNA structure formation is hierarchical and, therefore, secondary structure, the sum of canonical base-pairs, can generally be predicted without knowledge of the three-dimensional structure. Secondary structure prediction algorithms evolved from predicting a single, lowest free energy structure to their current state where statistics can be determined from the thermodynamic ensemble. This article reviews the free energy minimization technique and the salient revolutions in the dynamic programming algorithm methods for secondary structure prediction. Emphasis is placed on highlighting the recently developed method, which statistically samples structures from the complete Boltzmann ensemble. 相似文献