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191.
Giovanni Benelli Adriano Carpita Sandro Simoncini Alfio Raspi Angelo Canale 《Journal of pest science》2014,87(3):449-457
The braconid parasitoid Psyttalia concolor foraging for larvae of Bactrocera oleae (Diptera: Tephritidae) uses olfactory cues from the larval microhabitat. However, it could rely on the sex pheromones of adults of its host, since B. oleae mating leks usually occur on olive plants and a high number of infested fruits can be easily located in their close proximity. We quantified the behavioural responses of P. concolor towards different doses of the two major sex pheromone components of B. oleae, the female-borne 1,7-dioxaspiro[5.5]undecane (DSU) and the male-borne (Z)-9-tricosene (ZT). Results showed that P. concolor females and males were attracted only to the highest amounts of ZT (10 B. oleae male equivalents), regardless of the mating status. Wasps remained longer on the surfaces treated with high ZT amounts over the control. P. concolor females could exploit the ZT produced by lekking olive fruit fly males as a foraging kairomone. This could allow them to rapidly track B. oleae-infested olive plants, thus raising their chances to locate host larvae during their lifespan. On the other hand, the perception of ZT by P. concolor males could raise their chances to locate receptive females emerging from parasitised B. oleae pupae or also ovipositing in olive fruits. This study increases the knowledge of the reproductive biology of P. concolor, highlighting a case of chemical espionage in which a sex pheromone component from adult stages of the host is exploited both as a foraging kairomone by female parasitoids and as a sexual kairomone by male wasps. 相似文献
192.
Genoepidemiological evaluation of Bovine viral diarrhea virus 2 species based on secondary structures in the 5' untranslated region 总被引:2,自引:0,他引:2
Giangaspero M Harasawa R Weber L Belloli A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(6):571-580
Bovine viral diarrhea virus 2 (BVDV-2) strains demonstrated in cattle, sheep, and adventitious contaminants of biological products have been evaluated by the palindromic nucleotide substitutions (PNS) method at the three variable loci (V1, V2 and V3) in the 5' untranslated region (UTR), to determine their taxonomical status. Variation in conserved genomic sequences was used as parameter for epidemiological evaluation of the species in relation with geographical distribution, animal host and virulence. Four genotypes, BVDV-2a, BVDV-2b, BVDV-2c, and BVDV-2d have been identified within the species. Taxonomical segregation corresponded to geographical distribution of genotype variants. Genotype 2a was present worldwide, and was the only circulating also in sheep, in addition to cattle. Genotypes 2b, 2c and 2d were restricted to South America. Contamination of biological products was related to genotypes 2a and 2d. Genetic variation could be related with chronological diffusion of the BVDV-2 species variants in different geographic areas. Chronologically, the species emerged in North America in 1978, spreading in UK and Japan, continental Europe, South America and New Zealand. Correlation between clinical features related with isolation of BVDV-2 strains and genetic variation indicated that subgenotype 1, variant 4 of genotype 2a was related with hemorrhagic syndrome. These observations suggest that evaluation of genomic secondary structure, by identifying markers for expression of virus biological activities and species evolutionary history, may be applied as useful tool for epidemiological evaluation of the BVDV-2 species, and possibly for other species of the genus Pestivirus. 相似文献
193.
Visceral leishmaniasis (VL) is a life-threatening disease of medical, social and economic importance in endemic areas. Dogs are the main reservoir of Leishmaniainfantum. In this study, the authors investigated a group of 56 natural infected dogs to establish the relationship between parasite load and various clinical forms of leishmaniasis.The sick dogs were monitored at the beginning from clinical and physiological point of view. Leishmania load was measured by real-time PCR assay on whole blood samples and lymph node aspirates, collected at the time of diagnosis.Our results indicate that a higher quantity of Leishmania DNA was found in the lymph nodes of dogs characterized by maximum clinical score. This interesting finding indicates the presence of a positive relationship between Leishmania load and clinical manifestations in dogs showing a severe clinical form of leishmaniasis. 相似文献
194.
Chiara Mariti Eva Ricci Beatrice Carlone Jane L. Moore Claudio Sighieri Angelo Gazzano 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(3):135-145
Shared activities are known to create a good relationship between dog and man. Therefore, it can be expected that animals working in harness with their handlers, such as search and rescue dogs, show a higher attachment to man.The aim of the current research was to assess whether there are differences between pet and working dogs in the attachment to owners/handlers.Forty dogs were involved, 26 pets and 14 search and rescue dogs (taken home when not working). Their attachment to owners/handlers was analyzed by using a modified version of the Ainsworth Strange Situation Test and a recall test, while owners and handlers filled in a questionnaire and were scored on the Lexington Attachment to Pets Scale.Statistical analysis revealed no statistically significant differences between pet and working dogs for behaviors indicating an attachment bond: behavior oriented to door/chair/shoe during the absence of owner/handler (which represents “search of absent person”; U = 132.000, P = 0.156), contact with/proximity to owner/handler (i.e., “contact maintenance effect”; U = 157.000, P = 0.478), whining during owner's/handler's absence (“protest at the separation”; U = 147.000, P = 0.288), and individual play (U = 146.000, P = 0.288) and exploration (U = 138.500, P = 0.215) in presence of owner/handler, representing the “secure base effect.”Despite the lack of statistical differences, the formulated hypothesis may be not completely rejected, as a trend of a higher attachment in search and rescue dogs existed. It can be concluded that in carefully owned dogs, the level of attachment is increased by working as a search and rescue dog, but the difference does not lead to statistically relevant results. 相似文献
195.
196.
Daniele Cornara Maria Saponari Adam R. Zeilinger Angelo de Stradis Donato Boscia Giuliana Loconsole Domenico Bosco Giovanni P. Martelli Rodrigo P. P. Almeida Francesco Porcelli 《Journal of pest science》2017,90(2):521-530
The recent introduction of Xylella fastidiosa in Europe and its involvement in the Olive Quick Decline Syndrome (OQDS) in Apulia (Salento, Lecce district, South Italy) led us to investigate the biology and transmission ability of the meadow spittlebug, Philaenus spumarius, which was recently demonstrated to transmit X. fastidiosa to periwinkle plants. Four xylem-sap-feeding insect species were found within and bordering olive orchards across Salento during a survey carried out from October 2013 to December 2014: P. spumarius was the most abundant species on non-olive vegetation in olive orchards as well as on olive foliage and was the only species that consistently tested positive for the presence of X. fastidiosa using real-time PCR. P. spumarius, whose nymphs develop within spittle on weeds during the spring, are likely to move from weeds beneath olive trees to olive canopy during the dry period (May to October 2014). The first X. fastidiosa-infective P. spumarius were collected in May from olive canopy: all the individuals previously collected on weeds tested negative for the bacterium. Experiments demonstrated that P. spumarius transmitted X. fastidiosa from infected to uninfected olive plants. Moreover, P. spumarius acquired X. fastidiosa from several host plant species in the field, with the highest acquisition rate from olive, polygala and acacia. Scanning electron microscopy (SEM) revealed bacterial cells resembling X. fastidiosa in the foreguts of adult P. spumarius. The data presented here are essential to plan an effective IPM strategy and limit further spread of the fastidious bacterium. 相似文献
197.
Angelo Loy Sara Busilacchi Corrado Costa Ludovic Ferlin Stefano Cataudella 《Aquacultural Engineering》2000,21(4):673-283
The definition of a remote system in the monitoring of fin fish shape variability relies on the appropriate shape analysis tools. In this paper, different methods are proposed and compared. Growth trajectories, computed using geometric morphometrics, allow the pattern of size-related shape change and visualize growth allometry to be analyse. Geometric morphometrics is used to describe shape change in three samples (507 5100 days after hatching) of 119 individuals of the Sparid Diplodus puntazzo. The results are potentially interesting but the method still relies on the manual detection of homologous landmarks (coordinates of points located unambiguously on each specimen’s profile or structure) which are basic for such analysis. In an attempt to proceed towards the remote estimation and the automation of data collection, two alternative approaches are tested. In particular, Elliptic Fourier analysis and Bezier function were applied to the same samples, and results compared with geometric morphometrics. Fourier analysis’ growth curves are very similar to geometric morphometrics’ ones and allows for an appropriate visualisation of global shape changes. At the same time, Fourier methods can be applied to remotely and automatically detected profiles. This method is thus considered as the best candidate in the context of automated fish shape monitoring. The Bezier method performed poorly, both in terms of statistical output and shape visualization. 相似文献
198.
Dayani Bailly Valéria Flavia Batista-Silva Fernanda A. Silva Cassemiro Priscila Lemes Weferson Junio da Graça Anielly Galego de Oliveira Edivando Vitor do Couto José Hilário Delconte Ferreira Reginaldo Ré Thiago Fernando Rangel Angelo Antonio Agostinho 《水产资源保护:海洋与淡水生态系统》2021,31(9):2515-2532
- Freshwater ecosystems, providing valuable goods and services to humans, have been subjected to multiple human impacts, among which climate change plays a central role in threats to species. It is expected that protected areas, the cornerstone of biodiversity conservation efforts, will assume a decisive role in protecting freshwater species from the impacts of climate change.
- This study assessed the effects of climate change on migratory fish of the second largest neotropical river basin, evaluating the effectiveness of protected areas in safeguarding fish species, and hence the ecological functions that they perform and the ecosystem resources that they provide. The present range of 23 migratory fish of economic interest in the Paraná–Paraguay basin was estimated and the responses to future climatic shifts projected to the middle and end of the 21st century were examined, quantifying predictive uncertainties.
- Changes and losses of climatically suitable areas will trigger severe contractions in range, with the greatest impact on the most valuable species in commercial fishing, where range losses are likely to surpass 65% in the future. The main channel of the Upper Paraná River and tributaries of its left margin are projected to serve as climatic refuges for many species, and such regions are not affected by high predictive uncertainty. The results revealed that protected areas do not sufficiently protect migratory fish at present, and that they will continue to offer negligible protection in the face of climate change.
- This study alerts decision makers to the potential damage to inland fishery resources from climate change and provides useful information to guide conservation strategies spatially. We advocate that the creation of new protected areas and the redesign of the existing network to encompass regions that maximize current and future occupancy of migratory fish are crucial to conserve the valuable ecological, societal, and economic benefits that they provide.
199.
G Giovinazzo I Ingrosso A Paradiso L De Gara A Santino 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):191-199
The plant polyphenol trans-resveratrol (3, 5, 4'-trihydroxystilbene) mainly found in grape, peanut and other few plants, displays a wide range of biological effects. Numerous in vitro studies have described various biological effects of resveratrol. In order to provide more information regarding absorption, metabolism, and bioavailability of resveratrol, various research approaches have been performed, including in vitro, ex vivo, and in vivo models. In recent years, the induction of resveratrol synthesis in plants which normally do not accumulate such polyphenol, has been successfully achieved by molecular engineering. In this context, the ectopic production of resveratrol has been reported to have positive effects both on plant resistance to biotic stress and the enhancement of the nutritional value of several widely consumed fruits and vegetables. The metabolic engineering of plants offers the opportunity to change the content of specific phytonutrients in plant - derived foods. This review focuses on the latest findings regarding on resveratrol bioproduction and its effects on the prevention of the major pathological conditions in man. 相似文献
200.
Brad J. Nutt Angelo Loi Belinda Hackney Ron J. Yates Mario DAntuono Robert J. Harrison John G. Howieson 《Grass and Forage Science》2021,76(1):93-104
This paper reports on the evaluation of “summer sowing,” an innovative approach to increase the adoption of recently domesticated species of hard seeded annual legumes in Mediterranean and temperate Agriculture. The research revealed that several species of annual legumes whose seed can be readily harvested on‐farm and which possess natural hard seed dormancy, may be sown into dry soil in late summer without additional processing. These studies proved that the hard seed dormancy was broken down sufficiently in the soil over 4–6 weeks to produce robust legume pastures with more than 150 seedlings per m2 following the first winter rains, in replicated field sites established across wide agro‐ecological zones in Western Australia (WA) and New South Wales (NSW). Ornithopus sativus Brot., O. compressus L. and Trifolium spumosum L. were suitable for summer sowing based on both hard seed breakdown patterns and subsequent seedling survival in WA. While in NSW, in addition to these legumes, Biserrula pelecinus L., T. vesiculosum Savi. and T. glanduliferum Boiss. were also suitable for summer sowing. A 1.5‐ to 10‐fold increase in herbage production was achieved relative to conventionally sown T. subterraneum L. This development represents a step change in forage legume development for renovated pastures in these environments. Importantly, the experiments revealed differences in G x E effects on seedling establishment, total herbage production and seed yield in different climatic zones. The summer sowing approach is presented as a revolutionary method for pasture renovation that overcomes significant barriers to adoption. 相似文献