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81.
《Journal of Asia》2020,23(4):1062-1066
The objectives of study was to evaluate the vertical space of flying insects using YST (yellow sticky traps) trapping in a strawberry farm with a high-raised bed system; with assuming the presence of species-specific flying zone. The experimental farm used styrofoam beds (width 30 cm, depth 20 cm) placed on a supporting frame 70 cm high. Small YSTs (12.5 × 7.5 cm, single sticky side) were installed vertically around the high-raised bed system in a 3 × 7 configuration (column × row) vertically at 30-cm intervals, reaching 270 cm high, and spaced 50 cm apart horizontally. The trap positions within the second-ranking (here referred to as ‘zone’) to attract thrips were 60 cm traps above the top of the bed center (TBC), 30 cm traps above the side of the bed (SOB), and 70 cm traps from the ground on the SOB. The attraction zone of whiteflies was the same as that of the thrips except of the 60 cm traps above the SOB. The zones for leafhoppers were formed in all 60 cm traps above the top of the bed (TOB), the 90 cm side traps above the TOB, and 30 cm traps above the TBC. Aphids were frequently attracted at all 90 cm traps above the TBC and 60 cm above the TBC. Sciarid pests were mostly attracted to the traps placed just below the bed center. The zones of natural enemies (total) were formed in 30 cm above the TBC and 70 cm from the ground at the SOB. Thus, the zone 60 cm above the TBC was common position where various pests were frequently attracted with reducing a harmful effect on natural enemies. Consequently, our results could be used as a guideline for the use of YSTs in strawberry farms with high-raised bed systems until new directions are developed.  相似文献   
82.
The number of the diplopod, Trigoniulus lumbricinus (Gerst ) in the leaf litter varies between months. The annual population peak is reached during May to July after which the population declines. The seasonal population change is statistically correlated with the rainfall, but a causal relationship is difficult to establish: there is no indication that the population is regulated by any density related process either. It is speculated that a long term study of the population in different parts of its distribution range can only clarify the density relations.  相似文献   
83.
The Burkard Volumetric Spore Trap is a common and efficient instrument used to collect outdoor air samples. In North America, two slide counting methods have been widely used by aerobiologists: the single longitudinal traverse method and the twelve transverse traverse method. The purpose of this study was to compare the two counting methods by assessing fungal spore concentrations of ascospores, basidiospores, smut teliospores, Cladosporium, Alternaria, Epicoccum, Curvularia, Drechslera, Pithomyces, other spores, and total spores at two metropolitan Tulsa, Oklahoma sites (Tulsa and Hectorville) during September 1996. Results showed that both methods were sensing parallel fluctuations in average daily spore concentration, although the twelve transverse traverse method usually resulted in higher concentrations. At the Tulsa site, the twelve transverse traverse method gave statistically higher concentrations than the single longitudinal traverse method except for Epicoccum, Pithomyces, smut teliospores, and other spores. At the Hectorville site, however, only Cladosporium and basidiospores showed that the twelve transverse traverse method was statistically higher than the single longitudinal traverse method. Comparison with concentrations obtained by counting the total slide surface of two slides indicated that neither method was equivalent to the total slide spore count, although the twelve transverse traverse method gave a lower absolute percent difference from the total slide surface concentration. While the twelve transverse traverse method gave slightly better approximations of the spore concentration, the increase in accuracy may not justify the extra effort required to analyze with this method.  相似文献   
84.
In this study we investigated whether the recently discovered antagonist of the nociceptin/orphanin FQ (N/OFQ) opioid peptide (NOP) receptor, 1‐[1‐(cyclooctylmethyl)‐1,2,3,6‐tetrahydro‐5‐(hydroxymethyl)‐4‐pyridinyl]‐3‐ethyl‐1,3‐dihydro‐2H‐benzimidazol‐2‐one (Trap‐101) changed motor activity in naïve rats and mice, and alleviated parkinsonism in 6‐hydroxydopamine hemilesioned rats. In naïve rats, Trap‐101 stimulated motor activity at 10 mg/Kg and inhibited it at 30 mg/Kg. Such dual action was also observed in wild‐type but not NOP receptor knockout mice suggesting specific involvement of NOP receptors. Trap‐101 alleviated akinesia/bradykinesia and improved overall gait ability in hemiparkinsonian rats, being effective starting at 1 mg/Kg and without worsening motor deficit at 30 mg/Kg. To investigate the circuitry involved in the Trap‐101 action, behavioral tests were performed in rats undergoing microdialysis. The anti‐akinetic/anti‐bradykinetic effects of Trap‐101, given systemically (10 mg/Kg) or perfused in substantia nigra reticulata (10 μM), were associated with reduced glutamate and enhanced GABA release in substantia nigra, and reduced GABA release in ipsilateral ventro‐medial thalamus. When combined with ineffective doses of l ‐DOPA (0.1 mg/Kg), Trap‐101 evoked larger neurochemical and behavioral responses. These data show that Trap‐101 is an effective NOP receptor antagonist in vivo and confirm that NOP receptor antagonists alleviate parkinsonism through blockade of nigral NOP receptors and impairment of nigro‐thalamic transmission.  相似文献   
85.
The virgin female introduced pine sawfly, Diprion similis (Hartig ), produces a powerful sex pheromone capable of attracting males. Pending chemical identification of the substance, a pilot study in male annihilation is under consideration. A mathematical model was developed to assess the feasibility of population suppression using pheromone-baited traps. Departure from preexisting population models resulted chiefly from the arrhenotokous nature of the sawfly. The model predicts alternating sawfly generations which undergo first a large shift in the sex ratio but no population reduction, followed by a large decrease in population size with a moderating sex ratio. Four generations of intensive trapping would theoretically be sufficient to eliminate the sawfly from an isolated area.  相似文献   
86.
Pheromones have recently been suggested for use in insect pest control. We formulate a discrete version of a model with virgin females (or female equivalent of pheromone) in traps, and explore conditions under which this mechanism can eradicate the pest. Our model is density independent, thus when eradication is not possible, the pest increases without bound, in reality density dependent effects limit population growth. Successive refinements incorporating various features, show that delayed mating together with monogamy has a strong influence on the outcome, whereas other aspects of mating behaviour are relatively unimportant. All our models show that when males are in excess control is impossible but when some virgins are left unmated each day the outcome depends on the parameters. As the birth rate or survivorship increase, control by this method becomes more difficult.  相似文献   
87.
Pitfall traps baited with a lure containing a new pheromone component were used to catch adult Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) in the field in Tanzania. Traps baited with a mixture of Trunc-call (T1) and the new component Trunc-call (T2) caught ten times as many insects as traps baited with T1 alone. The data demonstrate for the first time that mixtures of T1 and T2 can be used as effective lures to trap P. truncatus in the field, and that P. truncatus is widespread outside of farm buildings in Africa.
Résumé Des pièges contre P. truncatus Horn, appâtés avec un leurre contenant une nouvelle phéromone ont été utilisés dans la nature en Tanzanie. Les pièges appâtés avec un mélange de Trunc-call 1 (T1) et du nouveau composé Trunc-call 2 (T2) capturent 10 fois plus d'insectes que ceux appâtés avec T1 seul. Ces résultats montrent pour la première fois que des mélanges de T1 et T2 peuvent être utilisés efficacement pour leurrer P. truncatus dans la nature, et que P. truncatus est abondant autour des fermes en Afrique.
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88.
Peter VOGEL 《Mammal Review》2012,42(4):314-318
The presence of the Etruscan shrew Suncus etruscus is hard to prove where its predator, the barn owl Tyto alba, is absent, because most live traps are not triggered by it. I therefore developed a new trapping method involving a feeding period of 1 week followed by one night of trapping using modified Trip Trap traps. I show here in detail how I caught four Etruscan shrews in 2010 with 24 traps in the Valley of Dora Baltea (Piemonte, Italy). In 2011, another 11 Etruscan shrews were caught in Piemonte and Lombardia, Italy, and Ticino, Switzerland. The proposed new method is useful for establishing the presence of the species.  相似文献   
89.
We have devised a census formula of curvilinear regression suitable for capture-recapture data of recapture-addicted populations of the Japanese field vole (Microtus montebelli) obtained under a grid-plan with single-catch traps in order to estimate the whole population. The equation is founded on the assumption that the trappable population on the initial day is increased in way of an exponential curve until it reaches to the whole during one trapping period. The effect of trap-preoccupation by marked and multiple collisions is considered in the formula. As a result of its application to field data of the vole, it has turned out that the equation is required for the data gained under the trapping plan with trap spacing 10m, but not for those under the plan with spacing 5m, to estimate the whole. A convenient method of analysis of the formula is offered here, but we have been yet unable to introduce assymptotic variance of estimates.  相似文献   
90.
In the trap bladder ofUtricularia vulgaris, increase in sucrose concentrations in bladder lumen fluid decreased resetting rate. Addition of 350 mM sucrose to lumen fluid stopped the resetting. Therefore, water seems to move down the water potential gradient between the lumen and the arm cells of bifid trichomes, which are the site of inlet in the water pathway. Application of dinitrophenol, sodium azide, KCN, monoiodoacetic acid or pentachlorophenol in lumen fluid much reduced the water outflow. Temperature coefficient of bladder resettings was about 2. No effect of darkness on resetting rate was found. These facts show that the resetting requires energy supplied from respiration and there exists an active ion transport mechanism somewhere in the water pathway. No effect on the resetting was seen upon immersing the bladder in 700 mM surcose solution. In the capital cells of the pavement epithelium in its outer and middle zones, which are the site of outlet in water pathway, membrance potential and resistance were lower than those in other cells. These facts indicate that bulk flow of the cell sap from the capital cells to the outside takes place by intracellular hydrostatic pressure.  相似文献   
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