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61.
Yorianta?Sasaerila Regine?Gries Gerhard?Gries Grigori?Khaskin Skip?King Stephen?Takács Hardi?) 《Chemoecology》2003,13(2):89-93
Summary. During peak calling activity by male oil palm bunch
moths, Tirathaba mundella Walker (Lepidoptera: Pyralidae), their
hairpencils, wings or entire body were extracted in hexane. Gas
chromatographic-electroantennographic detection (GC-EAD) analyses of
hair pencil extracts revealed four compounds that consistently elicited
responses from female antennae. The NMR spectrum of isolated compound 1,
and mass spectra and retention indices of compounds 1–4 suggested that
they were (3S,6S)-2,2,6-trimethyl-6-vinyl-tetrahydro-pyran-3-ol (1),
4-hydroxy-3-methoxy-benzaldehyde (2, vanillin),
6,10,14-trimethyl-2-pentadecanone (3), and
6,10,14-trimethyl-2-pentadecanol (4). Comparative GC and GC-MS analyses
of hair pencils extract and synthetic standards confirmed these
structural assignments. Moreover, comparative chromatography of
synthetic and hairpencil-isolated 1 on a Cyclodex-B column (which
separated the four stereoisomers with baseline resolution) revealed that
male T. mundella produce the SS-stereoisomer (SS-1). In field cage
bioassay experiments in Palembang, Indonesia, synthetic SS-1 and
vanillin in combination, but not singly, attracted female T. mundella.
SS-1 plus vanillin were as effective as male T. mundella in attracting
females. Compounds 3 and 4 did not enhance the blend's attractiveness.
Received October 11 2002; accepted March 14, 2003.
R1D="
Correspondence to: Gerhard Gries, email: gries@sfu.ca 相似文献
62.
Tamara Fraizer 《Behavioral ecology and sociobiology》1997,41(6):423-434
I develop a state-based dynamic model of behavior to demonstrate that size-dependent differences in temperature tolerances
are not necessary to account for the activity of small male digger wasps late in the day. In the model, males defend or patrol
the nesting area, wait near nests, or feed away from the nesting area depending on time of day, energy reserves and size rank.
I assume a large male competitive advantage, so mating opportunities decrease with size rank for territorial or patrolling
males and are rare for all waiting males; the costs of patrolling or defense are higher than the costs of waiting. If energy
reserves of all males are initially small, all males alternate feeding and territorial or patrolling behavior. If energy reserves
are initially large, large males patrol or maintain territories until they risk starvation and leave the area to feed. At
this time, smaller males that have conserved their resources by waiting and feeding may defend territories or patrol. I simulate
the behavior of three populations representing two species of Microbembex by assuming large initial energy reserves for populations in which males were territorial and small initial reserves for
populations in which males patrolled, and then convert the predicted time of activity to temperature using local regressions
from field studies. Temporal patterns in the activity of large and small males were similar to those actually observed, and
relationships between size and temperature predicted by the model corresponded to most observations and were sometimes positive.
Thus, the delayed activity of smaller males does not correspond to activity at higher temperatures and is probably not attributable
to size-dependent thermal tolerances, but may represent a temporal displacement of mating activity due to intra-sexual competition
and mediated by energetics. The model makes testable predictions on the timing of feeding and depletion of energy reserves
in relation to size and initial energy state, and suggests how differences among species may influence the temporal and spatial
organization of male mating behavior.
Received: 27 February 1997 / Accepted after revision: 26 July 1997 相似文献
63.
为了研究甲醛作用后大鼠肺细胞醛糖还原酶(AR)的活性变化以及AR在肺细胞损伤中的功能,首先通过大鼠肺细胞分离培养,观察甲醛对大鼠肺细胞AR活性的影响及AR抑制剂——盐酸小檗碱对AR活性的抑制作用;其次通过流式细胞仪检测甲醛及盐酸小檗碱对大鼠肺细胞周期和凋亡的影响.结果表明:1.0mmol·L-1甲醛作用24h使大鼠肺细胞AR活性显著增加,盐酸小檗碱对AR活性具有抑制作用;甲醛能够引起大鼠肺细胞凋亡,使G0/G1和S期的细胞比例下降,G2/M期的细胞比例增加;甲醛和盐酸小檗碱共同作用使大鼠肺细胞凋亡率较单纯甲醛组更高,同时G0/G1期的细胞比例增加,S和G2/M期的细胞比例下降.结果提示甲醛能够使大鼠肺细胞AR活性增加;AR活性增加可减少细胞凋亡,对甲醛引起的大鼠肺细胞损伤具有保护作用. 相似文献
64.
László Zsolt Garamszegi Balázs Rosivall Gergely Hegyi Eszter Szöllösi János Török Marcel Eens 《Behavioral ecology and sociobiology》2006,60(5):663-671
In intrasexual conflicts, contestants can rely on relative or absolute size of status badges to mediate aggressive behavior. Most studies focus on the response of focal animals to variation in status badges of their competitors; few have simultaneously considered the traits of both participants under experimental conditions. By simulating territorial intrusions, we tested the importance of two sexual traits [forehead patch size (FPS) and wing patch size (WPS)] in territorial behavior of males in a Hungarian population of the collared flycatcher, Ficedula albicollis. We presented a stimulus male to an unpaired resident male to examine whether the characteristics of the territory owner or those of the challenger were associated with the latency of the first attack of the owner, which is a good predictor of the territorial behavior in general. WPS of the stimulus male was a significant determinant of the latency of the first attack, as males with a larger WPS elicited quicker attacks from the residents than males with a small WPS. From the residents’ perspective, age appeared to influence their territorial behavior, as yearlings had shorter attack latencies than older males. Additionally, latency could be considered an individual-specific attribute because it varied consistently among males, even when the WPS of the stimulus male was controlled, and it was associated with pairing success. Contrary to findings in a Swedish population, FPS seemed to be unimportant in male–male competition in our population, which suggests population differences in the role of the two plumage traits. Our results indicate that in a territorial conflict, the characteristics of both participants are important. 相似文献
65.
van Dongen WF 《Die Naturwissenschaften》2008,95(6):537-545
Male paternity assurance behaviour during the female fertile period has been widely documented amongst birds. In contrast, how sex-specific behavioural strategies vary with local breeding synchrony levels remains largely unknown. This is important because, in many species, intra-population patterns of extra-pair fertilisation rates, and hence cuckoldry risk, are known to vary with the number of simultaneously fertile females. Each sex may therefore differ in how they behave towards male conspecifics during different degrees of breeding synchrony. Here I provide evidence of such sex-specific differences in the golden whistler (Pachycephala pectoralis), a species in which within-pair paternity assurance is negatively associated with breeding synchrony. Via simulated territorial intrusions using decoy males, I show that males, but not females, increase levels of aggression to male intruders during periods of low synchrony, possibly because cuckoldry risk is greatest during this period. In addition, males appear to invest more effort into mate guarding after, but not before, territorial intrusions during this period. These inter-sexual differences may reflect conflicts in interest between the sexes, with females consistently showing interest in males during the fertile period regardless of synchrony levels and males investing more resources into expelling intruders when the risk of paternity loss is greatest. This study thus provides evidence that males may be able to detect variation in breeding synchrony and cuckoldry risk and adjust their paternity assurance behaviour accordingly. 相似文献
66.
具有致癌性的抗氧化剂N—苯基—2-萘胺(P2NA)和N—苯基—1-萘胺(PINA)在体外籍新鲜分离的大鼠肝细胞进行生物转化.肝细胞培育后的产物经TLC和HPLC分析表明,二者主要代谢产物为酚类.P2NA生成二个酚类化合物,经与标准样品作平行层析证实为6-羟基P2NA和4'-羟基—P2NA,而P1NA仅生成一个酚类化合物.P2NA经去苯基反应的代谢产物2-萘胺未被检出. 相似文献
67.
68.
通过研究发育期大鼠脑单胺类神经递质质量比及单胺氧化酶活性,探讨环境暴露水平的六溴环十二烷对发育期大鼠的神经毒性作用。选择10μg/kg、50μg/kg、100μg/kg、300μg/kg的剂量对新生3 d大鼠进行暴露,饲养42 d后断头取脑组织,测定多巴胺(DA)、去甲肾上腺素(NE)、5-羟色胺(5-HT)的质量比及单胺氧化酶(MAO)的活性。结果表明,在10~100μg/kg的暴露剂量范围,DA质量比随暴露剂量的升高而下降,NE质量比呈现上升趋势,5-HT质量比则极显著性升高(p<0.01);与此同时,MAO的活性随剂量增加而升高,在100μg/kg剂量出现显著性升高(p<0.05)。而300μg/kg的剂量作为较高暴露水平的参照,只对DA产生显著性影响(p<0.05)。DA、5-HT、NE的质量比及MAO活性的变化可能在大鼠的中枢神经系统的发育障碍中发挥了重要作用,并且环境暴露水平的HBCD对发育期大鼠脑具有低剂量高效应的毒性反应特征。 相似文献
69.
Funda Karabag-Coban Ibrahim Bulduk Recep Liman Ibrahim Cigerci Omer Hazman 《毒物与环境化学》2016,98(1):101-108
The effects of acute exposure to 250 mg/kg malathion and the protective effects of 20 mg/kg oleuropein, both administered intraperitoneally, were evaluated in Wistar male rats. Malathion administration increased malondialdehyde, nitric oxide, 8-hydroxy-2′-deoxyguanosine, total oxidant status, and DNA damage, yet decreased total antioxidant activity, superoxide dismutase, and catalase activities in blood, liver, and kidney. Administration of oleuropein reversed malathion-induced oxidative stress, lipid peroxidation, DNA damage, and antioxidant enzyme activity. 相似文献
70.
Translocation is used to reestablish wild populations of animals, but translocation projects often do not meet their objectives because postrelease mortality of animals is high. One reason for translocation failure is that the behavioral or ecological requirements of released animals are unmet. Maintaining founder-group social relationships during release can affect reestablishment of social species. Solitary territorial species with stable neighbors (restricted dispersal and lifetime occupation of a home range) of the same species may also benefit from the maintenance of these social relationships during translocation. We translocated Stephens' kangaroo rats (Dipodomys stephensi), a solitary species listed as endangered under the U.S. Endangered Species Act, with and without neighboring kangaroo rats. We compared the settlement (establishment of a stable home range) decisions and fitness of kangaroo rats between the 2 treatments. Kangaroo rats translocated with neighbors traveled shorter distances before establishing territories, had higher survival rates, and had significantly higher reproductive success than kangaroo rats translocated without neighbors. Number of offspring was 24-fold higher for kangaroo rats translocated with neighbors than those translocated without neighbors. Differences in behavior following release may partially explain differences in survival between the 2 groups. Immediately following release, animals translocated with neighbors fought less and spent significantly more time foraging and digging burrows than animals translocated without neighbors. Our results indicate that even for solitary species, maintaining relationships among members of a translocated group of animals can influence translocation success. This study is the first empirical demonstration of the fitness consequences of disrupting social relationships among territorial neighbors. 相似文献