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71.
Dinh Thi Ngoc Nguyen Roel Rodriguez Suralta Mana Kano-Nakata Shiro Mitsuya Stella Owusu-Nketia 《Plant Production Science》2018,21(2):93-105
Rainfed lowland rice fields are characterized by soil moisture fluctuations (SMF) and the presence of hardpan that impedes deep rooting and thus limits water extraction from deep soil layer during the periods of drought. In this study, we used rootboxes with three layers; shallow layer, artificial hardpan, and deep and wet layer below the hardpan, to evaluate differences in the plasticity of nodal roots elongation through the hardpan and promote root branching below the hardpan in response to SMF among four rice varieties; Sasanishiki, Habataki, Nipponbare, and Kasalath. Experiments were conducted during the summer and autumn seasons. Plasticity was computed as the difference in root traits within each variety between the SMF and continuously well-watered treatments. In both experiments, Habataki consistently tended to exhibit higher root plasticity than the other three varieties by increasing number of nodal roots that penetrated the hardpan during rewatering period in SMF, when the soil moisture increased and penetration resistance decreased. This root plasticity then contributed to greater water use at the deeper soil during the subsequent drought period and overall shoot dry matter production. Habataki had significantly higher δ13C value in roots at deep layer than roots at the shallow and hardpan layers under SMF, which may indicate that these were relatively newly grown roots as a consequence of root plasticity. This study also indicates that CSSLs derived from Sasanishiki and Habataki varieties may be suitable for the analysis of QTLs associated with root plasticity expression in rainfed lowland with hardpan and experiencing SMF. 相似文献
72.
Venneria E Fanasca S Monastra G Finotti E Ambra R Azzini E Durazzo A Foddai MS Maiani G 《Journal of agricultural and food chemistry》2008,56(19):9206-9214
The genetic modification in fruit and vegetables could lead to changes in metabolic pathways and, therefore, to the variation of the molecular pattern, with particular attention to antioxidant compounds not well-described in the literature. The aim of the present study was to compare the quality composition of transgenic wheat ( Triticum durum L.), corn ( Zea mays L.), and tomato ( Lycopersicum esculentum Mill.) to the nontransgenic control with a similar genetic background. In the first experiment, Ofanto wheat cultivar containing the tobacco rab1 gene and nontransgenic Ofanto were used. The second experiment compared two transgenic lines of corn containing Bacillus thuringiensis "Cry toxin" gene (PR33P67 and Pegaso Bt) to their nontransgenic forms. The third experiment was conducted on transgenic tomato ( Lycopersicum esculentum Mill.) containing the Agrobacterium rhizogenes rolD gene and its nontransgenic control (cv. Tondino). Conventional and genetically modified crops were compared in terms of fatty acids content, unsaponifiable fraction of antioxidants, total phenols, polyphenols, carotenoids, vitamin C, total antioxidant activity, and mineral composition. No significant differences were observed for qualitative traits analyzed in wheat and corn samples. In tomato samples, the total antioxidant activity (TAA), measured by FRAP assay, and the naringenin content showed a lower value in genetically modified organism (GMO) samples (0.35 mmol of Fe (2+) 100 g (-1) and 2.82 mg 100 g (-1), respectively), in comparison to its nontransgenic control (0.41 mmol of Fe (2+) 100 g (-1) and 4.17 mg 100 g (-1), respectively). On the basis of the principle of substantial equivalence, as articulated by the World Health Organization, the Organization for Economic Cooperation and Development, and the United Nations Food and Agriculture Organization, these data support the conclusion that GM events are nutritionally similar to conventional varieties of wheat, corn, and tomato on the market today. 相似文献
73.
74.
Fishing constitutes a key source of income and food for rural communities worldwide. This is the case in predominantly rural Myanmar (World Fish, 2019), particularly in the Ayeyarwady (Irrawaddy) River Delta. Fishing has long been a central livelihood strategy and valuable source of food security in the Delta, and now also generates a substantial contribution to the gross domestic product. However, the livelihood practices of the fishers, particularly small‐scale fishers, are largely ‘invisible’ in the literature and policy. In this article, we advance understanding of the significant but understudied livelihoods of small‐scale fishers through interviews with fishers and a range of other actors in 2018. Taking a careful examination of the challenges, practices and responses of fishers in the Delta, our research underlines that fishers are important actors in the ‘making’ of the Delta as a geographical scale and concept, yet they are being pushed out of the very landscape they have helped co‐create and have lived in for generations. At this crucial point in Myanmar's development and change, we contend that a better understanding of the livelihoods of fishing households, as some of the nation's most vulnerable, is important for inclusive policy development, economic reforms and research strategy going forward. 相似文献
75.
Panagiotis A Papamichalis Kalliopi Zachou George K Koukoulis Aikaterini Veloni Efthimia G Karacosta Lampros Kypri Ioannis Mamaloudis Stella Gabeta Eirini I Rigopoulou Ansgar W Lohse George N Dalekos 《Journal of Autoimmune Diseases》2007,4(1):3
Background
We conducted a study in order to determine the usefulness and diagnostic value of International Autoimmune Hepatitis Group (IAHG) score in non-autoimmune hepatitis (AIH) hepatic disorders as well as in AIH/overlap syndromes and in cases with coexistence of AIH and other liver diseases.Methods
We applied the IAHG score in 423 patients with liver diseases excluding patients with AIH, AIH/overlap syndromes and AIH with concurrent other liver disease namely, patients with chronic hepatitis B (n = 109), chronic hepatitis C (n = 95), chronic hepatitis D (n = 4), alchoholic liver disease (n = 28), non-alcoholic fatty liver disease (n = 55), autoimmune cholestatic liver diseases (n = 77), liver disorders of undefined origin (n = 32) and with miscellaneous hepatic disorders (n = 23). 24 patients with AIH associated with any kind of liver disorder including 10 patients with AIH/overlap syndromes and 14 AIH with concurrent other liver disease were also investigated. 43 patients with AIH consisted the control group.Results
The specificity of the score was 98.1% while the sensitivity in unmasking AIH in patients with either AIH/overlap syndromes or AIH with concurrent other liver diseases was only 50% and 78.6%. In the binary logistic regression model, the presence of other autoimmune diseases (p < 0.001), the total histological score (p < 0.001) and positivity for autoantibodies (p < 0.05) were identified as independent predictors for the presnce of AIH/ovea syndromes o AI with concurren other liver diseass.Conclusion
The IAHG scoring system has very good specificity for excluding AIH in patients with chronic liver diseases but not that sensitivity in order to unmask AIH/overlap syndromes or AIH with concurrent other liver diseases. The presence of other autoimmune diseases or autoantibody markers in the absence of hepatitis viral markers should alarm physicians for the possible presence of AIH either as "pure" AIH or in association with other liver disorders (AIH/overlap syndromes or AIH with concurrent other liver diseases). Under these conditions, liver histology seems essential and it must always be included in the work up of hepatic patients.76.
The possibility to induce embryo development after pollination of F1 interspecific cotton hybrids (Gossypium barbadense × Gossypium. hirsutum) with pollen from Abelmoschus esculentus was investigated to determine if wide-cross hybrid, haploid or other types of progeny might result. Small numbers of progeny
(Pa) were indeed recovered after numerous alien pollinations and in-planta development or in-vitro culture. The Pa plants
were characterized phenotypically and studied cytogenetically and microscopically to help establish their origin documenting
their reproductive basis. Root-tip chromosome counts and meiotic Metaphase-I analyses revealed that chromosome numbers among
cells of the Pa plants ranged from 33 to 44 and that the differences in chromosome number among cells of the same plant ranged
from 1 to 3, indicating somatic instability. Flow cytometric analysis also indicated the aneuploid nature of Pa plants. Although
the reproductive mechanisms need to be characterized more extensively by cytological and molecular means, the observations
suggest that alien pollinations may have resulted in parthenogenetic (Pa) egg cell development, or some other unusual reproductive
events. The production of wide-crosses and high degrees of aneuploidy could be of use for several types of genomic studies,
e.g., functional genomic characterization of genome shock, deletion mapping, and germplasm introgression. 相似文献
77.
Pereyra CM Cavaglieri LR Chiacchiera SM Dalcero AM 《Veterinary research communications》2011,35(6):367-379
The aim of the present study was to determine the mycobiota and natural levels of mycotoxins such as zearalenone, fumonisin
B1, aflatoxin B1 and ochratoxin A present in raw materials and finished fattening pig feed. Samples were examined for total fungi and genera
distribution. Zearalenone, FB1, AFB1 and OTA contamination were determined using high pressure liquid chromatography and thin layer chromatography. Milled maize
and finished feed samples showed fungal contamination over than 1 × 104 CFU/g. All samples contained at least one of the main mycotoxigenic genera Aspergillus, Fusarium and Penicillium. A. flavus and F. verticillioides were the most prevalent species. Only some Aspergillus section Nigri strains from suckling pig to growing pig samples were able to produce OTA. A. flavus strains from milled maize, wheat bran, suckling pig to growing pig samples were able to produce AFB1. All samples were positive for FB1. Sucking pig, piglet, growing and boar feed samples showed ZEA natural contamination. AFB1 and OTA contamination were not detected. There was a 100% correlation between FB1 and ZEA contamination in sucking pig, piglet, growing and boar feed samples; 50% piglet samples and 67% suckling pig samples
showed ZEA levels over the recommended limits. The present study has shown the occurrence of two mycotoxins, FB1 and ZEA in feed intended for fattening pig consumption. In animal production, the simultaneous presence of toxicogenic fungi
and low dietary levels of mycotoxins in field conditions can cause possible health impacts and lost performance in pigs from
feeding spoiled feeds. 相似文献
78.
María Laura Tonelli Ana Furlan Tania Taurian Stella Castro Adriana Fabra 《Physiological and Molecular Plant Pathology》2011,75(3):100-105
Selected strains of rhizobacteria induce systemic resistance in plant (ISR), enhancing the capacity to mobilize infection-induced cellular defense responses (priming). Bacillus sp. CHEP5 and Pseudomonas sp BREN6 strains reduced root and stem wilt disease severity caused by Sclerotium rolfsii in Arachis hypogaea L. Strains inoculation increased the activity of phenylalanine ammonia-lyase and peroxidase, after pathogen-challenge, indicating priming. CHEP5 primes plants to produce more ethylene upon stimulation with ACC. A. hypogaea L is an ISR-positive plant and BREN6 and CHEP5 strains enhance the plant’s defense capacity by priming for potentiated activity of defense proteins and ACC-converting capacity. 相似文献
79.
Previous simulations of a self-avoiding, closed random surface with restricted topology (without handles) on a three-dimensional lattice have shown that its behavior on long length scales is consistent with that of a branched-polymer. It is shown analytically that such a surface with an unrestricted number of handles has a qualitatively different geometry and therefore is in a different universality class. The effect of a net external pressure is to suppress the handles and collapse the surface into a branched polymer-like configuration. Topology is thus shown to be a key factor in determining the universality class of the system. 相似文献
80.
Jorge Olivar Stella Bogino Cyrille Rathgeber Vivien Bonnesoeur Felipe Bravo 《Annals of Forest Science》2014,71(3):395-404