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461.
A new genus Sumatrella gen. n. is described and illustrated based on the new species Sumatrella chelonica sp. n. collected in Sumatra, Indonesia. The new genus belongs to the family Oplitidae based on its hypertrichous internal malae and the absence of strongly sclerotized structures on the dorsal shield. The new genus is closely related to the genus Chelonuropoda Sellnick, 1954 but the transverse furrow on ventral idiosoma close to coxae IV and the strongly sclerotized C-shaped dorsal line are missing in the new genus. These characters can be found in species of Chelonuropoda.  相似文献   
462.
Understanding what shapes variation in genetic diversity among species remains a major challenge in evolutionary ecology, and it has been seldom studied in parasites and other host‐symbiont systems. Here, we studied mtDNA variation in a host‐symbiont non‐model system: 418 individual feather mites from 17 feather mite species living on 17 different passerine bird species. We explored how a surrogate of census size, the median infrapopulation size (i.e., the median number of individual parasites per infected host individual), explains mtDNA genetic diversity. Feather mite species genetic diversity was positively correlated with mean infrapopulation size, explaining 34% of the variation. As expected from the biology of feather mites, we found bottleneck signatures for most of the species studied but, in particular, three species presented extremely low mtDNA diversity values given their infrapopulation size. Their star‐like haplotype networks (in contrast with more reticulated networks for the other species) suggested that their low genetic diversity was the consequence of severe bottlenecks or selective sweeps. Our study shows for the first time that mtDNA diversity can be explained by infrapopulation sizes, and suggests that departures from this relationship could be informative of underlying ecological and evolutionary processes.  相似文献   
463.
Methyl benzoate is a newly discovered natural insecticide. In this study, we evaluated methyl benzoate as a potential fumigant for controlling four pests including western flower thrips (WFT), Frankliniella occidentalis, lettuce aphid, Nasonovia ribisnigri, rice weevil, Sitophilus oryzae, and bulb mites, Rhizoglyphus spp., at different temperatures and effects on post-harvest quality of apples. Methyl benzoate fumigations were effective against all four pests. Complete control of WFT and lettuce aphid was both achieved in 8, 16 and 24 hr at 25, 13 and 2°C, respectively. For rice weevil, complete control was achieved in 16 and 72 hr with and without rice at 25°C, respectively. Complete control of bulb mites was achieved in 64 hr at 25°C on peanut. In addition, a 24 hr methyl benzoate fumigation at 2°C had complete control of WFT but had no negative impact on visual quality of apples of three varieties 4 weeks after fumigation. These results suggest that methyl benzoate fumigation has potential to be an alternative treatment to methyl bromide fumigation, which has been phased out, for post-harvest pest control for stored products and may also have potential to control other pests on fresh products.  相似文献   
464.
目的:探讨过敏原检测在幼儿喘息性疾病中的临床应用价值。方法:选择我院儿科收治的的1~5岁下呼吸道感染的特应性体质患儿217例,按照有无喘息症状分为喘息组与非喘息组。采集并比较两组患儿年龄、性别、过敏史(食物过敏,药物过敏,鼻炎,湿疹)、体外过敏原检测结果:TIgE(总IIgE)及sIgE(特异性IgE),(视sIgE≥2级为阳性)、一二级亲属过敏性疾病史。结果:(1)喘息组反复呼吸道感染及鼻炎人数均高于非喘息组(P0.05)。两组在湿疹、喜揉眼、食物过敏、药物过敏、一级亲属过敏史、二级亲属过敏史方面比较差异不具有统计学意义(P0.05)。(2)两组体外过敏原检测结果比较:喘息组户尘螨阳性人数多于非喘息组;(3)喘息患儿组根据是否伴有鼻炎及湿疹分为:A组,喘息,不伴有鼻炎及湿疹;B组,喘息伴有鼻炎或者湿疹;C组,喘息,伴有鼻炎及湿疹。ABC三组TIgE、年龄、吸入过敏原个数、吸入过敏原阳性人数、户尘螨阳性率逐渐增多,差异具有统计学意义(P0.05),其他吸入过敏原及食入过敏原比较差异无统计学意义。结论:反复呼吸道感染、鼻炎和喘息密切相关。尘螨是幼儿喘息、变应性鼻炎和特应性皮炎主要过敏原之一,是特应性体质患儿是否发生喘息的关键过敏原。  相似文献   
465.
Wang CF  Kuo CC  Jeng ML  Huang KW 《ZooKeys》2011,(102):1-11
Morphological variation of Huangiella lanyuensis (Huang, 2001) and Tumoris sanasaii Huang, 2001 from Taiwan was analyzed using multivariate statistical methods. We show that these species are the same and propose to use the name Tumoris sanasaii. No significant differences between populations from Lanyu and Green Island (type localities for Huangiella lanyuensis and Tumoris sanasaii, respectively) were found; however, mites from Yangmingshan (northern Taiwan) differed substantially from these two groups. Synonymy resulted from our study is as follows: Huangiella Kammerer, 2006 is a junior synonym of Tumoris Huang, 2001; Absentia lanyuensis Huang, 2001 is a junior synonym of Tumoris sanasaii Huang, 2001. We also study the sexual variation of populations from Green Island. The result showed the females significantly larger than the males at 17 variables.  相似文献   
466.
Adults and deutonymphs of a new water mite species of the genus Hygrobates Koch, 1837 (Acari, Hydrachnidia, Hygrobatidae) were found to parasitize the Hong Kong Newt, Paramesotriton hongkongensis Myers and Leviton, 1962 (Amphibia, Caudata, Salamandridae), endemic to Hong Kong and coastal areas of Guangdong Province: Hygrobates aloisii sp. nov. Males and females, as well as deutonymphs and larvae are described. A new subgenus - Lurchibates subgen. nov. - is defined to accommodate the species of the Hygrobates salamandrarum-group. The parasite-host association, infestation rate, attachment sites and the impact of mite infestation on the newts behaviour and body condition are investigated. These ecological aspects of the parasite-host association between freshwater mites and newts are examined for the first time in detail in their natural habitat.  相似文献   
467.
记述寄生在蜡梅Chimonanthus praecox( Linn.) Link.(蜡梅科Calycanthaceae)叶子上的瘿螨2新种:蜡梅离子瘿螨Leipothrix chimonae sp.nov.和蜡梅双羽爪瘿螨Diptacus praecox sp.nov..模式标本保存在河北大学博物馆.蜡梅离子瘿螨,新种Leipothrix chimonae sp.nov.(图1~5)正模♀,副模:25♀♀,2 ♂ ♂,2009-06-01,陕西省岚皋县蜡烛村,海拔600m,谢满超采.寄主为蜡梅Chimonanthus praecox( Linn.) Link.(蜡梅科Calycanthaceae).新种与悬钩子离子瘿螨Leipothrix yipiingae Shi,2000相似,但新种背盾板具背中线,雌生殖盖片基部具纵线,端部饰有斜线,羽状爪3支,而悬钩子离子瘿螨L.yipingae背盾板上无背中线,雌生殖盖片饰有短线和粒点,羽状爪4支.蜡梅双羽爪瘿螨,新种Diptacus praecox sp.nov.(图6-12)正模♀,副模:8♀♀,7 ♂ ♂,2009-06-01,陕西省岚皋县蜡烛村,海拔600m,谢满超采.寄主为蜡梅Chimonanthus praecox( Linn.)Link.(蜡梅科Calycanthaceae). 新种与臭樱双羽爪瘿螨Diptacus maddenis Song,Xue et Hong,2007相似,但新种足Ⅰ基节间具胸线,基节饰有线条和粒点,雌生殖器盖片上饰有1排纵肋,而臭樱双羽爪瘿螨D.maddenis足Ⅰ基节间无胸线,基节饰有粒点,雌生殖器盖片基部饰有粒点.  相似文献   
468.
  • 1 Invertebrate pests, such as blue oat mites Penthaleus spp., cause significant economic damage to agricultural crops in Australia. Climate is a major driver of invertebrate species distributions and climate change is expected to shift pest assemblages and pest prevalence across Australia. At this stage, little is known of how individual species will respond to climate change.
  • 2 We have mapped the current distribution for each of the three pest Penthaleus spp. in Australia and built ecological niche models for each species using the correlative modelling software, maxent . Predictor variables useful for describing the climate space of each species were determined and the models were projected into a range of future climate change scenarios to assess how climate change may alter species‐specific distribution patterns in Australia.
  • 3 The distributions of the three cryptic Penthaleus spp. are best described with different sets of climatic variables. Suitable climate space for all species decreases under the climate change scenarios investigated in the present study. The models also indicate that the assemblage of Penthaleus spp. is likely to change across Australia, particularly in Western Australia, South Australia and Victoria.
  • 4 These results show the distributions of the three Penthaleus spp. are correlated with different climatic variables, and that regional control of mite pests is likely to change in the future. A further understanding of ecological and physiological processes that may influence the distribution and pest status of mites is required.
  相似文献   
469.
Li HS  Xue XF  Hong XY 《ZooKeys》2012,(196):47-107
Eriophyoid mites from Qinghai Province, northwestern China were studied herein. Up to now, only six species have been reported from Qinghai Province. In field surveys, 17 eriophyoid mite species were collected, among which nine species were found new to science. The new species and their host plants are listed as follows: Acaphyllisa tuberculumaesp. n. on Populus sp. (Salicaceae); Proiectus xiningensissp. n. on Pinus sp. (Pinaceae); Phyllocoptes beishaniensissp. n. on Spiraea mongolica Maxim. (Rosaceae); Tetra prunianasp. n. on Prunus tomentosa Thunb. (Rosaceae) Rupr. (Berberidaceae); Tetra pyrianasp. n. on Pyrus calleryana Decne. (Rosaceae); Tetra simoniasp. n. on Populus simonii Carr. (Salicaceae); Diptacus berberinussp. n. on Berberis amurensis Rupr. (Berberidaceae); Diptacus mengdaensissp. n. on Lonicera elisae Franch. (Caprifoliaceae); Rhyncaphytoptus spinussp. n. on Lonicera rupicola Hook. f. et Thoms. (Caprifoliaceae). Aculops ulmi Hong & Xue, 2005 was re-described.  相似文献   
470.
Male secondary sexual traits often scale allometrically with body size. These allometries can be variable within species and may shift depending on environmental conditions, such as food quality. Such allometric plasticity has been hypothesized to initiate local adaptation and evolutionary diversification of scaling relationships, but is under‐recorded, and its eco‐evolutionary effects are not well understood. Here, we tested for allometric plasticity in the bulb mite (Rhizoglyphus robini), in which large males tend to develop as armed adult fighters with thickened third legs, while small males become adult scramblers without thickened legs. We first examined the ontogenetic timing for size‐ and growth‐dependent male morph determination, using experimentally amplified fluctuations in growth rate throughout juvenile development. Having established that somatic growth and body size determine male morph expression immediately before metamorphosis, we examined whether the relationship between adult male morph and size at metamorphosis shifts with food quality. We found that the threshold body size for male morph expression shifts toward lower values with deteriorating food quality, confirming food‐dependent allometric plasticity. Such allometric plasticity may allow populations to track prevailing nutritional conditions, potentially facilitating rapid evolution of allometric scaling relationships.  相似文献   
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