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121.
【目的】明确热带平刺粉蚧Rastrococcus tropicasiaticus Williams的鉴别特征,建立平刺粉蚧属种类检索表。【方法】随机抽样、形态学观察和测量。【结果】从进口越南龙眼鲜果中截获热带平刺粉蚧,头胸部腹面多格腺以单排排列,体背面大五格腺少是其识别的主要形态学特征;编制了平刺粉蚧属16种检索表。【结论】热带平刺粉蚧为我国口岸首次检出,研究结果为进口水果中该类粉蚧的检疫鉴定提供了重要的参考资料。  相似文献   
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Mi?osz A. Mazur 《ZooKeys》2016,(554):87-118
The genus Rasilinus gen. n. is described (type species Rasilinus tchambicus sp. n.). Nine new species: Rasilinus bicolor sp. n., Rasilinus bifurcatus sp. n., Rasilinus bimaculatus sp. n., Rasilinus grandidens sp. n., Rasilinus longulus sp. n., Rasilinus subgemellus sp. n., Rasilinus subnodulus sp. n., Rasilinus tchambicus sp. n., Rasilinus virgatus sp. n. are described from New Caledonia. Illustrations of the external morphology, male and female terminalia, dorsal habitus colour photographs of the adults, key to species and distribution map of the new genus Rasilinus are provided.  相似文献   
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Pseudoogeton maoxianum sp. n. is described from Sichuan, China. A key to the males of the species of Pseudoogeton Masumoto, 1989 is presented.  相似文献   
125.
It has been suggested that image-forming eyes promote the evolutionary diversification (measured by species richness) of the groups that possess them. Several different processes could give rise to this effect, including diversifying selection in a new adaptive zone (or zones) and a reduced rate of extinction due to enhanced competitive abilities. I tested the generality of the hypothesis that imaging eyes increase net speciation by comparing extant species numbers of 12 groups that have such eyes (as categorized by Land and Fernald 1992) with those of their cladistic sister groups that lack such organs. Even assuming the published hypotheses of phylogenetic relationships that most favor increased net speciation of visual groups, these comparisons show no significant association between imaging eyes and species richness. Increased activity, as indicated by published accounts of locomotory speed, is significantly associated with the evolution of image-forming eyes. This suggests that a large “visual adaptive zone” might be characterized by relatively high activity. However, when diversity comparisons are limited to eight cases in which the evolution of imaging eyes is associated with increased activity, there is still no significant association between such eyes and species richness. The fossil record indicates that the only visual groups that have undergone major evolutionary radiations evolved imaging eyes early in the history of metazoans (before the Silurian). The radiations of these early groups may have largely filled up niches for visual animals and thus prevented the subsequent proliferation of other groups with image-forming eyes. Alternatively, it may be that image-forming eyes have no exceptional effect on diversification or that their effects are obscured by other factors in the long run.  相似文献   
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Goal, Scope and Background To strengthen the evaluative power of LCA, life cycle interpretation should be further developed. A previous contribution (Heijungs & Kleijn 2001) elaborated five examples of concrete methods within the subset of numerical approaches towards interpretation. These methods were: contribution analysis, perturbation analysis, uncertainty analysis, comparative analysis, and discernibility analysis. Developments in software have enabled the possibility to apply the five example methods to explore the much-used Ecoinvent”96 database.Discussion of Methods The numerical approaches implemented in this study include contribution analysis, perturbation analysis, uncertainty analysis, comparative analysis, discernibility analysis and the newly developed key issue analysis. The data used comes from a very large process database: Ecoinvent’96, containing 1163 processes, 1181 economic flows and 571 environmental flows. Conclusions Results are twofold: they serve as a benchmark to the usefulness and feasibility of these numerical approaches, and they shed light on the question of stability and structure in an often-used large system of interconnected processes. Most of the approaches perform quite well: computation time on a moderate PC is between a few seconds a few minutes. Only Monte Carlo analyses may require much longer, but even then it appears that most questions can be answered within a few hours. Moreover, analytical expressions for error propagation are much faster than Monte Carlo analyses, while giving almost identical results. Despite the fact that many processes are connected to each other, leading to the possibility of a very unstable system and very sensitive coefficients, the overall results show that most results are not extremely uncertain. There are, however, some exceptions to this positive message.  相似文献   
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The genus Etiennea Matile‐Ferrero is synonymized with Hemilecanium Newstead (Hemiptera: Coccidae). We base this decision on a morphological comparative study of adult females, adult males and first‐instar nymphs (crawlers), including a phylogenetic analysis. We recovered a sister group relationship between the type species of the two genera, Etiennea villiersi Matile‐Ferrero and Hemilecanium theobromae Newstead; that is, each was more closely related to the other than either was to other species in their respective genera. All species hitherto included in Etiennea are transferred to Hemilecanium: H. bursera (Hodgson & Kondo) comb. nov., H. cacao (Hodgson) comb. nov., H. candelabra (Hodgson) comb. nov., H. capensis (Hodgson) comb. nov., H. carpenteri (Newstead) comb. nov., H. cephalomeatus (Hodgson) comb. nov., H. combreti (Hodgson) comb. nov., H. ferina (De Lotto) comb. nov., H. ferox (Newstead) comb. nov., H. gouligouli (Hodgson) comb. nov., H. halli (Hodgson) comb. nov., H. kellyi (Brain) comb. nov., H. madagascariensis (Hodgson) comb. nov., H. montrichardiae (Newstead) comb. nov., H. multituberculum (Hodgson) comb. nov., H. petasus (Hodgson) comb. nov., H. sinetuberculum (Hodgson) comb. nov., H. tafoensis (Hodgson) comb. nov., H. ulcusculum (Hodgson) comb. nov., and H. villiersi (Matile‐Ferrero) comb. nov. Keys to the adult females of all 26 species and known adult males and first‐instar nymphs are provided. The adult males and first‐instar nymphs of H. theobromae Newstead and E. villiersi Matile‐Ferrero are for the first time fully described and illustrated. One new potential pest species of Hemilecanium, H. uesatoi Kondo & Hardy sp. nov., which was collected on three islands of the Ryukyu Archipelago, Japan, is described and illustrated based on the adult female, adult male and first‐instar nymph. We discuss evidence that H. uesatoi is a new introduction to the Ryukyu Archipelago. The first‐instar nymphs of Hemilecanium can be divided into two distinct morphological groups, the petasus group and the theobromae group.  相似文献   
130.
The identification of adaptations and key innovations has long interested biologists because they confer on organisms the ability to exploit previously unavailable ecological resources and respond to novel selective pressures. Although it can be extremely difficult to test for the effects of a character on the rate of lineage diversification, the convergent evolution of a character in multiple lineages provides an excellent opportunity to test for the effect of that character on lineage diversification. Here, I examine the effect of parity mode on the diversification of vipers, which have independently evolved viviparity in at least 13 lineages. I find strong statistical evidence that viviparous species diversify at a greater rate than oviparous species and correlate major decreases in the diversification rate of oviparous species with periods of global cooling, such as the Oligocene. These results suggest that the evolution of viviparity buffered live-bearing species against the negative effects of global climate change during the Cenozoic, and was a key innovation in the evolution and diversification of live-bearing vipers.  相似文献   
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