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41.
Here we examine dispersal, metrosis, and claustrality in the seed-harvester ant Pogonomyrmex salinus at an unusually large mating aggregation. We found that mode of queen dispersal from the mating aggregation is not a function of queen mass and that wing damage among queens was relatively rare. P. salinus is haplometrotic in the field and foundress queens placed together in forced associations eventually fight to the death. While queens of Pogonomyrmex salinus can survive claustrally, producing a single minim from their body reserves in the laboratory, fed queens produce up to four significantly larger minims along with concurrent larvae and pupae during the same period. Since queens forage in the field, we interpret claustrality as a secondary reserve strategy when foraging fails, and suggest that foraging is obligate for P. salinus queens in an overdispersed and temperate environment. Thus, nest founding strategies employed by P. salinus may be environmentally determined and represent a continuum between fully claustral and obligate foraging. We discuss our results with reference to theories of pleometrosis and claustral colony founding. Received 12 November 2004; revised 12 April 2004; accepted 29 July 2005.  相似文献   
42.
吸烟是导致慢性阻塞性肺疾病(COPD)发生发展的主要原因之一.但吸烟者是否发生COPD存在个体差异,其机制尚未完全阐明.蛋白质组学研究能够高效率发现疾病相关蛋白并为深入研究疾病的发病机制提供线索.本研究运用二维凝胶电泳(2-DE)和基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)蛋白质组学研究方法结合生物信息学数据,对吸烟COPD患者和非COPD吸烟者肺组织表达的差异蛋白进行筛选和鉴定,共鉴定出24种差异蛋白,涉及基本代谢酶类、氧化应激相关酶类、凝血/纤溶相关蛋白、蛋白降解相关酶以及细胞生长分化相关蛋白等.本研究结果为进一步探索COPD的发病机制提供了新的线索.  相似文献   
43.
Protonated peptides derived from proline‐rich proteins (PRP) are often difficult to sequence by standard collision‐induced dissociation (CID) mass spectrometry (MS) due to preferential amide bond cleavage N‐terminal to proline. In connection with bovine spongiform encephalopathy regulations, proteolytic products derived from the PRP collagen have been suggested as markers for contamination of animal feedstuffs with processed animal protein (Fernandez Ocaña, M. et al., Analyst 2004, 129, 111–115). Herein, we report the identification of these marker peptides using the strategy of C‐terminal sequencing by CID MS from their sodium and lithium adducts. Upon fragmentation a new cationized peptide was produced that is one C‐terminal amino acid shorter in length. This dissociation pathway allowed for the facile identification of the C‐terminal residue by matrix‐assisted laser desorption/ionization tandem time‐of‐flight mass spectrometry. Each newly formed cationized peptide was further fragmented by up to seven stages of electrospray ionization ion trap MS. Proline‐rich C‐terminal sequence tags were established which permitted successful database identification of collagen alpha type I proteins.  相似文献   
44.
1. There are numerous data that support the trade‐off between flight capability and reproduction in female wing polymorphic insects, but the relationship between wing form and fitness remains poorly investigated in males. 2. In the present study, the development of flight muscle and gonads, spermatophore size, and multiple copulation ability were investigated in both long‐winged (LW) and short‐winged (SW) males to verify this trade‐off, using a wing dimorphic cricket species Velarifictorus aspersus (Walker). 3. The LW males had better‐developed wing muscles than the SW males on the day of emergence, and both of them developed wing muscles after emergence, but the peak of weight in SW males was achieved 4 days later than that of the LW males. The accessory glands (AG) of the LW males developed significantly slower than that of the SW males. These results suggest that development and maintenance of flight muscles have a cost on the development of reproductive organs in male V. asperses. 4. The SW males produced significantly heavier spermatophores in a single copulation and mated more often than LW males. This indicates the SW males have a higher mating success than the LW males, thereby increasing their chance of siring offspring.  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.
Electroantennogram (EAG) measurement of male Cydia caryana moth antennal olfactory response to monounsaturated 12 and 14 carbon alcohols and acetates indicated that the (E)-8-, (E)-10- conjugated double bond system of a dodecadien-1-ol acetate is a critical chemical structural component of the C. caryana sex pheromone. Additionally, EAG measurements implicated (E)-8-dodecen-1-ol acetate, (Z)-8-dodecen-1-ol acetate, (Z)-9-dodecen-1-ol acetate and (Z)-12-tetradecen-1-ol as potential minor pheromonal components. An EAG dosage-response study suggested that there were at least two heterologous populations of pheromone acceptors. Behavioral analysis of male moth response in a flight tunnel to compounds which evoked the stronger EAG responses suggested that (E,E)-8,10-dodecadien-1-ol acetate and (Z)-9-dodecen-1-ol acetate resemble or are C. caryana sex pheromonal components, while (Z)-8-dodecen-1-ol acetate and (E)-10-dodecen-1-ol acetate are either parapheromones or are minor pheromone components. Behavioral significance of (Z)-12-tetradecen-1-ol was difficult to interpret in the flight tunnel.
Résumé Les réponses olfactives antennaires de Cydia caryana, mesurées par électroantennogrammes (EAG), aux alcools et acétates à carbones monounsaturés en positions 12 et 14, ont montré que le système conjugué de double liaison, (E)-8-, (E)-10- du dodecadien-1-ol acétate constitue un composé chimique strutural critique de la phéromone sexuelle de C. caryana.De plus, les acétates: (E)-8-dodecen-1-ol,(Z)-8-dodecen-1-ol,(Z)-9-dodecen-1-ol, et le (Z)-12-tetradecen-1-ol, se sont révélés en AEG comme des composés secondaires de la phéromone. L'étude par AEG de la relation dose-réponse a conduit à l'hypothèse de deux catégories de populations de récepteurs de phéromones. L'analyse comportementale des résponses des papillons mâles dans le tunnel de vol aux composés qui ont provoqués les plus forts AEG, on fait estimer que les acétates (E,E)-8,10-dodécadien-1-ol et (Z)-9-dodecen-1-ol ressemblent (ou sont) les constituants de la phéromone sexuelle de C. caryana; tandis que les (Z)-8-dodecen-1-ol et (E)-10-dodecen-1-ol sont, soit des paraphéromones, soit des constituants mineurs de la phéromone.La signification biologique du (Z)-12-tétradécen-1-ol a été difficile à interprêter avec les expériences en tunnel de vol.
  相似文献   
47.
48.
ABSTRACT

In this paper a new method for the automatic classification of bird sounds is presented. Our method is based on acoustic parameters (features) taken from the first harmonic component computed from the sound spectrogram. The features are based on a line segment approximation of the first harmonic component. The final feature vectors, consisting of 16 real numbers, are then classified using a self-organizing map (SOM) neural network. Flight calls of four crossbill species (Loxia spp.) are used as a test example. In the first phase, an unsupervised network was trained and tested using common crossbill L. curvirostra flight calls recorded mainly in the Netherlands. The network was tested using two-barred L. leucoptera, Scottish L. scotica and parrot L. pytyopsittacus crossbill flight calls in the second phase. Finally, the results were validated applying the same network to flight calls of common crossbills and parrot crossbills recorded in Finland. The method automatically separated common crossbill flight calls from those of parrot crossbills. The classification accuracy of the Dutch recordings was 58% in the first phase and 54% in the second phase. The Finnish recordings were classified with 54% accuracy.  相似文献   
49.
Regulatory peptides represent a diverse group of messenger molecules. In insects, they are produced by endocrine cells as well as secretory neurones within the CNS. Many regulatory peptides are released as hormones into the haemolymph to regulate, for example, diuresis, heartbeat or ecdysis behaviour. Hormonal release of neuropeptides takes place at specialized organs, so-called neurohaemal organs. We have performed a mass spectrometric characterization of the peptide complement of the main neurohaemal organs and endocrine cells of the Drosophila melanogaster larva to gain insight into the hormonal communication possibilities of the fruit fly. Using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) and MALDI-TOF-TOF tandem mass spectrometry, we detected 23 different peptides of which five were unpredicted by previous genome screenings. We also found a hitherto unknown peptide product of the capa gene in the ring gland and transverse nerves, suggesting that it might be released as hormone. Our results show that the peptidome of the neurohaemal organs is tagma-specific and does not change during metamorphosis. We also provide evidence for the first case of differential prohormone processing in Drosophila.  相似文献   
50.
This paper is focused on the model identification of a Micro Air Vehicle (MAV) in straight steady flight condition. The identification is based on input-output data collected from flight tests using both frequency and time dorrtain techniques. The vehicle is an in-house 40 cm wingspan airplane. Because of the complex coupled, multivariable and nonlinear dynamics of the aircraft, linear SISO structures for both the lateral and longitudinal models around a reference state were derived. The aim of the identification is to provide models that can be used in future development of control techniques for the MAV.  相似文献   
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