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131.
垂直监测昆虫雷达研究进展   总被引:2,自引:0,他引:2  
昆虫雷达可以远距离、 大范围、 快速地探测迁飞昆虫, 这极大促进了人类对昆虫迁飞行为的认识。垂直监测昆虫雷达技术是从20世纪70年代发展起来的一种监测高空迁飞昆虫种群的新工具。与传统的扫描雷达相比, 垂直监测昆虫雷达可以获得目标的位移速度、 位移方向、 定向、 体型大小和形状等参数, 因此, 对目标的识别能力更为精确。此外, 垂直监测昆虫雷达实现了在微机控制下的自动运行, 这使得应用昆虫雷达开展迁飞昆虫的日常监测成为可能。本文综述了垂直监测昆虫雷达的发展和应用, 介绍了设计原理和回波参数的解算方法, 讨论了其存在的不足及改进方案, 最后并对其在未来昆虫雷达网络建设中的应用进行了展望。  相似文献   
132.
Abstract   The Australian Entomological Society was founded in 1965 and provides a journal of world-class and annual scientific meetings for members. The world-wide impact of entomology publications is growing faster than that of the Australian Journal of Entomology , and membership of the society is declining slowly. In a recent survey members were generally happy with the society, but much of the exciting research involving insects is probably being published in specialist journals. Challenges identified for the future include building membership through greater connection with amateur entomologists and with students interested in ecology and insects. The growth area for entomology is seen to be in the application of insect biodiversity to the sustainable management of Australia's ecosystems. This special issue of the journal includes 10 papers illustrating the breadth and depth of entomology in the society.  相似文献   
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Abstract.  The utility of cytochrome oxidase I (COI) DNA barcodes for the identification of nine species of forensically important blowflies of the genus Chrysomya (Diptera: Calliphoridae), from Australia, was tested. A 658-bp fragment of the COI gene was sequenced from 56 specimens, representing all nine Chrysomya species and three calliphorid outgroups. Nucleotide sequence divergences were calculated using the Kimura-two-parameter distance model and a neighbour-joining (NJ) analysis was performed to provide a graphic display of the patterns of divergence among the species. All species were resolved as reciprocally monophyletic on the NJ tree. Mean intraspecific and interspecific sequence divergences were 0.097% (range 0–0.612%, standard error [SE] = 0.119%) and 6.499% (range 0.458–9.254%, SE = 1.864%), respectively. In one case, a specimen that was identified morphologically was recovered with its sister species on the NJ tree. The hybrid status of this specimen was established by sequence analysis of the second ribosomal internal transcribed spacer (ITS2). In another instance, this nuclear region was used to verify four cases of specimen misidentification that had been highlighted by the COI analysis. The COI barcode sequence was found to be suitable for the identification of Chrysomya species from the east coast of Australia.  相似文献   
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The first two cases of the occurrence of Megaselia abdita Schmitz (Diptera: Phoridae) in human corpses in Britain are reported and a further case of M. rufipes (Meigen). In all three cases the corpses experienced low temperatures.  相似文献   
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Global population growth and an increasing demand for meat has driven the intensification of livestock production. On poultry farms, the accumulation of waste such as faeces, carcasses and unsellable eggs creates environmental and health hazards that need to be mitigated. The larvae of the black soldier fly (Hermetia illucens; BSFL) offer a potential solution to the problems of waste management on poultry farms. BSFL consume large quantities of organic waste and convert it into larval biomass, which can then be processed for use as livestock feeds or biofuels. This makes BSFL an ideal candidate for value-added waste management on chicken farms. Here, we examined the development and nutrient profile of BSFL given five different diet treatments: poultry feed (control), chicken meat, chicken egg, chicken manure and a mixture of equal parts chicken meat, egg and manure. Chicken meat, egg and mixed diets were all found to be suitable feedstocks for BSFL, but the manure-only treatment was associated with a high failure rate of larval development. Mixing manure with other poultry waste streams ameliorated the negative impacts of manure on BSFL. Larvae reared on chicken meat, egg and the mixed diet had equal or higher mean crude protein (CP) (39.9%, 33.8% and 31.5%, respectively) and crude lipid (CL) contents (30.1%, 29.00% and 28.7%, respectively), compared with BSFL reared exclusively on chicken feed (CP: 30.9%, CL: 23.8%), demonstrating the suitability of these waste-stream diets for the potential animal feed quality of the BSFL. We discuss how BSFL bioconversion could be implemented to address environment management issues on poultry farms.  相似文献   
139.
王毅  丰育功  唐万忠  程磊 《生物磁学》2013,(34):6679-6681
目的:探讨显微手术治疗后交通动脉瘤的手术时机,避免术后脑积水的手段及双侧后交通动脉瘤的处理方法。方法:采用翼点入路,早期显微手术夹闭后交通动脉瘤41例,两例双侧后交通动脉瘤患者成功采用一侧翼点入路夹闭双侧动脉瘤。结果:本组41例动脉瘤均顺利夹闭,28例患者术前存在动眼神经麻痹,27例术后症状消失或者缓解,1例未有明显改善。41例患者均行终板造瘘,术后出现脑积水患者1例。无死亡病例。随访1~10月无动脉瘤残留及复发。结论:早期手术夹闭后交通动脉瘤有利于动眼神经麻痹的恢复,术中行终板造瘘可降低术后脑积水的发生,对侧后交通动脉瘤的指向、位置及后交通动脉与颈内动脉的解剖关系是影响一侧入路夹闭双侧后交通动脉瘤的关键因素。  相似文献   
140.
目的:通过手术显微镜对前交通动脉复合体及穿支进行解剖和测量,进一步熟悉和掌握该复合体的结构及毗邻血管的走行,为前交通动脉瘤手术提供解剖学依据。方法:用红色乳胶经颈内动脉对15例(30侧)福尔马林固定的湿性尸头进行灌注,然后在手术显微镜下对前交通动脉复合体进行解剖观测,所得结果用SPSS17.0软件进行统计分析。测量大脑前动脉A1和A2段、前交通动脉、Heubner回返动脉、A1段和前交通动脉穿支的长度、直径和各种形态变异。结果:未经选择的标本双侧A1发育无明显差异;术中对Heubner回返动脉、A1段穿支、前交通动脉穿支应仔细分辨加以保护;A1中1/3段穿支少,可作为前交通动脉瘤手术时临时阻断A1的部位;血管造影时前交通动脉不易看清与多种因素有关。结论:前交通动脉复合体复杂多变,熟悉前交通动脉复合体及穿支的解剖特点,对外科医生处理该区疾病至关重要。  相似文献   
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