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211.
212.
Fipronil, a compound belonging to a new chemical family, the phenylpyrazols, was tested as a barrier treatment in Mauritania against bands of hoppers of the desert locust (Schistocerca gregaria, Forskal1775). An ultra-low volume formulation (ADONIS 12.5UL) was applied at 15.7 and 16.6/km. The doses were 1.96 and 1.04 g ai/ protected ha. Two sites of approximately 2800 and 7200 ha were sprayed from a helicopter flying at 20m. There were 12 track spacings, ranging from 330m to 2600m. The effects of fipronil on hopper bands were determined by comparison with the initial locust populations at the two sites. Several hopper bands were monitored in two untreated areas. The hopper bands were controlled within two days in the area up to 500m from the flight path, within 7 days in the area between 1000 and 2000m, and within 12 days in the area between 2000 and 2600m. The speed of mortality was related to the upwind distance from the flight path. When ADONIS 12.5UL (12.5g ai/l of fipronil) is applied at 16 l/km, at 20m height, with track spacings up to 1000m, the efficacy was similar to that obtained with a blanket treatment (11 g ai/ha) performed the previous year in Mauritania. 相似文献
213.
Hester J. van Schalkwyk Thomas Adams Antoine Persoons Willem H. P. Boshoff Ruth Wanyera Mogens S. Hovmøller Cristobal Uauy Lesley Boyd Zacharias A. Pretorius Renée Prins Diane G. O. Saunders 《Plant pathology》2022,71(2):279-288
Wheat stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici (Pst), occurs in all major wheat-growing regions worldwide and poses a constant threat to production. In South Africa, Pst first emerged in 1996 in the Western Cape and has since caused frequent epidemics with three further distinct races (pathotypes) recorded to date. Herein, we undertook detailed genomic-based analyses of four Pst isolates that represent the four dominant Pst races in South Africa recorded between 1996 and 2005. This analysis identified a number of polymorphic genes with features of known effector proteins and provided additional support of the likely stepwise changes in virulence profile of these South African Pst isolates. Next, we carried out comparative genomic-based analyses with 54 additional Pst isolates collected across wheat-growing regions within South Africa between 1996 and 2017 and 58 Pst isolates from East Africa, Pakistan, the UK, and France. This revealed a close genetic relationship between Pst isolates in South Africa and a number from East Africa. Furthermore, we found the South African Pst isolates also grouped closely with isolates identified in the UK in 2013 that were specifically found on triticale, illustrating long-distance transmission of Pst isolates either between these regions or from a common independent source area. This highlights the critical need for close monitoring of Pst. With wheat being the most planted winter cereal crop in South Africa, investment in continuous surveillance is essential to rapidly identify any future introductions that could quickly lead to rust epidemics. 相似文献
214.
重组卡介苗感染树突细胞的研究 总被引:1,自引:1,他引:1
焦新安 Richard Lo-Man Edith Deriaud Nathalie Winter Claude Leclerc 刘秀梵 《扬州大学学报(农业与生命科学版)》2002,23(1):1-5
在体内外试验中 ,树突细胞 (DC)均能摄取表达大肠杆菌麦芽糖结合蛋白 (MalE)的重组卡介苗 (rBCG·MalE)。应用流式细胞术测得荧光标记的rBCG·MalE在体内感染DC的水平在 1 % 2 % ,与感染巨噬细胞 (MΦ)的水平相当。体外抗原提呈试验结果显示 ,DC和MΦ能吞噬、加工rBCG·MalE并向T细胞杂交瘤FBU·B1 1提呈MalE蛋白抗原表位 ,而在体内试验中 ,从rBCG·MalE免疫小鼠脾脏中纯化的DC ,可检测到MalE表位MHCⅡ复合物 ,而纯化的MΦs却测不到。这表明DC在起始抗分枝杆菌的免疫保护中发挥关键作用。 相似文献
215.
216.
A number of brain systems have been implicated in addictive behavior, but none have yet been shown to be necessary for maintaining the addiction to cigarette smoking. We found that smokers with brain damage involving the insula, a region implicated in conscious urges, were more likely than smokers with brain damage not involving the insula to undergo a disruption of smoking addiction, characterized by the ability to quit smoking easily, immediately, without relapse, and without persistence of the urge to smoke. This result suggests that the insula is a critical neural substrate in the addiction to smoking. 相似文献
217.
Marivaux L Welcomme JL Antoine PO Métais G Baloch IM Benammi M Chaimanee Y Ducrocq S Jaeger JJ 《Science (New York, N.Y.)》2001,294(5542):587-591
In the absence of a comprehensive fossil record, the origin and early evolution of Malagasy lemurs have been subject to much uncertainty. We report here the discovery of a strepsirrhine fossil with strong cheirogaleid lemur affinities, Bugtilemur mathesoni gen. et sp. nov., from early Oligocene deposits of the Bugti Hills (Balochistan, Pakistan). Bugtilemur represents the earliest record of Lemuriformes, which hence appear to have already diversified outside of Madagascar at least 30 million years ago. This fossil clearly enhances the critical role of the Indian subcontinent in the early diversification of lemurs and constrains paleobiogeographic models of strepsirrhine lemur evolution. 相似文献
218.
Renaud G Lazzari R Revenant C Barbier A Noblet M Ulrich O Leroy F Jupille J Borensztein Y Henry CR Deville JP Scheurer F Mane-Mane J Fruchart O 《Science (New York, N.Y.)》2003,300(5624):1416-1419
One challenge in the production of nanometer-sized objects with given properties is to control their growth at a macroscopic scale in situ and in real time. A dedicated ultrahigh-vacuum grazing-incidence small-angle x-ray scattering setup has been developed, yielding high sensitivity and dynamics. Its capabilities to derive the average particle shape and size and the film growth mode and ordering and to probe both surfaces and buried interfaces are illustrated for two prototypical cases: the model catalyst Pd/MgO(100) and the self-organized Co/Au(111) system. A wide range of technologically important systems can potentially be investigated in various gaseous environments. 相似文献
219.
Chronic mucocutaneous candidiasis in humans with inborn errors of interleukin-17 immunity 总被引:1,自引:0,他引:1
Puel A Cypowyj S Bustamante J Wright JF Liu L Lim HK Migaud M Israel L Chrabieh M Audry M Gumbleton M Toulon A Bodemer C El-Baghdadi J Whitters M Paradis T Brooks J Collins M Wolfman NM Al-Muhsen S Galicchio M Abel L Picard C Casanova JL 《Science (New York, N.Y.)》2011,332(6025):65-68
Chronic mucocutaneous candidiasis disease (CMCD) is characterized by recurrent or persistent infections of the skin, nails, and oral and genital mucosae caused by Candida albicans and, to a lesser extent, Staphylococcus aureus, in patients with no other infectious or autoimmune manifestations. We report two genetic etiologies of CMCD: autosomal recessive deficiency in the cytokine receptor, interleukin-17 receptor A (IL-17RA), and autosomal dominant deficiency of the cytokine interleukin-17F (IL-17F). IL-17RA deficiency is complete, abolishing cellular responses to IL-17A and IL-17F homo- and heterodimers. By contrast, IL-17F deficiency is partial, with mutant IL-17F-containing homo- and heterodimers displaying impaired, but not abolished, activity. These experiments of nature indicate that human IL-17A and IL-17F are essential for mucocutaneous immunity against C. albicans, but otherwise largely redundant. 相似文献