百菌清及其三氟衍生物对番茄早疫病菌的室内抑菌活性比较

采用生长速率法测定了不同浓度的百菌清及其三氟衍生物对番茄早疫病菌Alternaria solani(Ell,et Mart.)Jones es Gmut的室内杀菌毒力。试验结果表明，百菌清及其三氟衍生物的ED50值分别为6089．89mg／L和156．43mg/L。，前者是后者的38．93倍。百菌清三氟衍生物的毒力明显高于百菌清。     

Physiological and behavioral effects of coniferyl benzoate on avian reproduction

Various plant secondary metabolites related to cinnamic acid are of interest because of their repellency to birds and their occurrence in ecologically important food items. Coniferyl benzoate (CB), a phenylpropanoid ester that occurs in quaking aspen (Populus tremuloides) is of particular ecological interest because of its effect on ruffed grouse (Bonasa umbellus) feeding behavior and its possible influence on the population dynamics of this bird. During detoxification processes, CB and other analogous compounds are metabolized into by-products, such as ferulic acid (FA), that can cause anti-reproductive effects. We tested whether consumption of CB produces antire-productive effects similar to FA using male and female Japanese quail (Coturnix coturnix) as avian models for ruffed grouse. The parameters we investigated included: the production, morphology, and development of eggs; reproductive characteristics influenced by estrogen; serum prolactin levels; and male reproductive behavior. Dietary CB did not produce antireproductive effects similar to FA at intake levels that Japanese quail and ruffed grouse would freely consume. Consumption of CB by Japanese quail significantly reduced egg production and body mass but did not affect male reproductive performance. Coniferyl benzoate's effect on egg production may be explained by lower energy acquisition and retention rather than endocrine changes per se. Contrary to previous reports, it is unlikely that FA, or similar compounds act directly as estrogen mimics or antagonists. Although, CB did reduce egg production in quail, it is unlikely that it would affect egg production in wild ruffed grouse. Detoxification costs and the effects of CB on nutrient utilization may explain why ruffed grouse avoid high dietary levels of CB.     

Effect of qualitative and quantitative variation in allelochemicals on a generalist insect: Iridoid glycosides and the southern armyworm

The behavioral and physiological effects of plant allelochemicals have been difficult to demonstrate; it is not often clear whether the compounds are deterrent, toxic, or both. In this study, we compared the qualitative and quantitative effects of several iridoid glycosides on a generalist lepidopteran herbivore,Spodoptera eridania (Noctuidae). Larval growth and survivorship and larval preference or avoidance were measured on artificial diets containing different iridoid glycosides at different concentrations. We also tested the toxicity/deterrence of these compounds. We found that iridoid glycosides retarded larval growth significantly at relatively low concentrations and that they were usually avoided in preference tests. The toxicity/ deterrence test did not always reflect the results of these other tests. The merits of using a variety of methods for determining deterrence and/or toxicity of plant allelochemicals are discussed.     

Olfactory aposematism

Visual and acoustic cues may serve as aposematic signals that warn predators of poisonous foods. Olfactory aposematism, the use of innocuous odors as warning signals for toxic foods, is another possible means of alerting an animal that a potential food item is unpalatable. Although it has been suggested that olfactory aposematism might be the principle mode of warning utilized by plants in their defense against herbivores, experimental evidence is lacking. This study demonstrates that the opossum,Didelphis virginiana, can utilize an innocuous volatile compound found naturally in a mushroom as a warning signal for a delayed illness caused by mushroom toxin. This supports the contention that characteristic odors of toxic plants may serve a warning function, protecting herbivores from being poisoned and plants from being consumed.     

白蚁提取液急性毒性及致突变性研究

本文采用大,小鼠急性经口毒性试验、Ａｍｅｓ试验、小鼠骨髓细胞微核试验及小鼠精子畸变试验对白蚁提取液的毒理学安全性进行了研究,结果表明,白蚁提取液大,小鼠急性经口ＬＤ５０均大于１０ｇ／ｋｇ体重,属“实际无毒”：体内（包括体细胞和生殖细胞）、体外致突变性试验系统均未检出其致突性。     

Quantification of heart fatty acid binding protein as a biomarker for drug-induced cardiac and musculoskeletal necroses

Heart fatty acid binding protein (Fabp3) is a cytosolic protein expressed primarily in heart, and to a lesser extent in skeletal muscle, brain, and kidney. During myocardial injury, the Fabp3 level in serum is elevated rapidly, making it an ideal early marker for myocardial infarction. In this study, an MS‐based selected reaction monitoring method (LC‐SRM) was developed for quantifying Fabp3 in rat serum. Fabp3 was enriched first through an immobilized antibody, and the protein was digested on beads directly. A marker peptide of Fabp3 was quantified using LC‐SRM with a stable isotope‐labeled peptide standard. For six quality control samples with Fabp3 ranging from 0.256 to 25 ng, the average recovery following the procedure was about 73%, and the precision (%CV) between replicates was less than 7%. The Fabp3 concentrations in rat serum peaked 1 h after isoproterenol treatment, and returned to baseline levels 24 h after the dose. Elevated Fabp3 levels were also detected in rats administered with a PPAR α/δ agonist, which has shown to cause skeletal muscle necrosis. Fabp3 can be used as a biomarker for both cardiac and skeletal necroses. The cross‐validation of the LC‐SRM method with an existing ELISA method is described.     

Defensive secretion of rice bug,Leptocorisa oratorius fabricius, (Hemiptera: Coreidae): A unique chemical combination and its toxic,repellent, and alarm properties

Defensive secretion produced by adult males and females ofLeptocorisa oratorius, Fabricius (Hemiptera: Coreidae) living on the host plant,Oriza sativa, was analyzed by a combined gas chromatography-mass spectroscopy technique. Both male and female secretions consisted of two major components: (E)-2-octenal andn-octyl acetate, 76% and 16% (w/w), respectively. The remaining 8% were trace compounds, some of which were identified as hexyl acetate, 3-octenal, 1-octanol, and (Z)-3-octenyl acetate. In a survey among 38 coreid defensive secretions, (E)-2-octenal andn-octyl acetate were found to occur rarely in addition to coreid-specific compounds, while their combination as primary constituents was found to be unique. Toxicity and repellency of this secretion were evaluated using two household pests,Anoplolepis longipes andSitotroga cerealella, as test insects, and lethal concentration (LC₅₀) values of 0.24 ppm and 0.14 ppm, respectively, and repellencies of 63% and 58%, respectively, were obtained. Comparing the above values with those of a pentatomid bug,Coridius janus, evaluated under the same conditions, it was apparent that this secretion has potential as a repellent to enemies ofL. oratorius but not as a toxicant to attack them. Bioassay on the alarm activity of this secretion revealed that it elicits alarm responses, alerting and dispersing aggregated male and femaleL. oratorius: this is followed by self-coating activities. In addition, some unique behaviors were also noted among alarmedL. oratorius.     

背诵在英语教学中的重要性

由于交际法的盛行，考试指挥棒的效应以及新的教学模式的出现，目前，我国外语教学对语言输入重视不够，背诵式输入几乎无立足之地。通过理论探索、实验测试和访谈等调查方式证实了背诵对学生写作和口语的提高有着显著的帮助，说明了背诵在中国英语教学应用的重要性，并就此提出，在运用西方教学新理论和现代教学手段时，不可忽视我国传统教学上的优势。     

电缆材料绿色化的两大指标——毒性和有害元素的检测和分析

采用了电缆材料绿色化的两大指标———毒性和有害元素含量的两种检测方法,即细胞毒性试验和电感耦合等离子体发射光谱仪法,认为这两种方法具有简便、精确、快速和省钱等优点,文中也提供了某电缆阻水膏和某种电缆护套料分别进行毒性试验和有害元素检测和分析。     

浅谈工程技术口译

结合口译的特点及笔的翻译实践讨论了如何作好工程技术口译工作，具体包括克服心理障碍；积累知识，充分准备；勤于实践；灵活的应变能力等。