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101.
102.
This research situates new farmers within the counter-urbanization phenomenon, explores their urban–rural migration experiences and examines how they are becoming a part of the rural agricultural landscape. Key characteristics in new farmers’ sense of place constructions are revealed through an ethnographic study conducted in southern Ontario, Canada, during the summer of 2009. Using a sense of place framework comprised of place identity, place attachment, and sense of community, this research details a contemporary concept of place to provide a fresh perspective on new farmers. It uncovers underlying motivations, goals, and values attached to rural agricultural landscapes as well as the “everyday” interactions and challenges experienced by those transitioning into rural farming communities. New farmers are found to draw unevenly from both the physical and social landscape of the urban and rural environments in the creation of a sense of place. This finding raises important questions about the socio-spatial dynamics that underscore the place of food and the local food movement. 相似文献
103.
A Colling C Morrissy J Barr G Meehan L Wright W Goff LJ Gleeson B van der Heide S Riddell M Yu D Eagles R Lunt S Khounsy Ngo Than Long Pham Phong Vu Nguyen Than Phuong Nguyen Tung W Linchongsubongkoch J Hammond M Johnson WO Johnson H Unger P Daniels JR Crowther 《Australian veterinary journal》2014,92(6):192-199
104.
OX Cordero H Wildschutte B Kirkup S Proehl L Ngo F Hussain F Le Roux T Mincer MF Polz 《Science (New York, N.Y.)》2012,337(6099):1228-1231
In animals and plants, social structure can reduce conflict within populations and bias aggression toward competing populations; however, for bacteria in the wild it remains unknown whether such population-level organization exists. Here, we show that environmental bacteria are organized into socially cohesive units in which antagonism occurs between rather than within ecologically defined populations. By screening approximately 35,000 possible mutual interactions among Vibrionaceae isolates from the ocean, we show that genotypic clusters known to have cohesive habitat association also act as units in terms of antibiotic production and resistance. Genetic analyses show that within populations, broad-range antibiotics are produced by few genotypes, whereas all others are resistant, suggesting cooperation between conspecifics. Natural antibiotics may thus mediate competition between populations rather than solely increase the success of individuals. 相似文献
105.
John T. Buchanan Ta Chi Cheng Jerome F. La Peyre Richard K. Cooper Terrence R. Tiersch 《Journal of the World Aquaculture Society》2001,32(3):286-299
The eastern oyster Crassostrea virginica provides a commercially valuable industry along the eastern and Gulf coasts of the United States. Recently this industry has been damaged by disease problems, creating an interest in the use of gene transfer (transfection) to improve disease resistance. We transfected adult oysters with two genes, red-shifted green fluorescent protein ( rsGFP ), commonly used as a reporter gene, and the lytic peptide cecropin B ( cepB ), known to have antimicrobial properties. Oysters were transfected by injecting DNA mixed with SuperFect™ reagent (Qiagen Inc.) into the adductor muscle sinus. Oysters were assigned to three groups of 15: the first was injected with rsGFP complexed with transfecting reagent: the second was injected with cepB complexed with transfectlng reagent; and the third was injected with saline (control group). Hemolymph was collected at 4 and 10 d after injection. DNA was extracted for analysis by polymerase chain reaction (PCR), and hemocytes were examined by flow cytometry and fluorescence microscopy for detection of green fluorescence due to rsGFP expression. The rsGFP gene was detected by PCR in hemocytes from 14 of 15 oysters at day 4, and in 15 of 15 oysters at day 10. The cepB gene was detected by PCR in 12 of 15 oysters at day 4 and in 14 of 15 oysters at day 10. No oysters from the control group were positive for either gene at days 4 or 10. Green fluorescence was detected by flow cytometry at significantly higher levels ( P < 0.05) in oysters injected with rsGFP than in other oysters at day 4, but not at day 10. This report indicates the ability to introduce DNA into adult eastern oysters with subsequent gene expression. Future work will involve developing these techniques for enhanced disease resistance in oysters. 相似文献
106.
Qiuyun Lin Wenyan Wang Yakun Ren Yimei Jiang Ailing Sun Ying Qian Yifei Zhang Niqing He Ngo Thi Hang Zhou Liu Linfang Li Linglong Liu Ling Jiang Jianmin Wan 《Breeding Science》2015,65(5):411-419
Seed storability in rice (Oryza sativa L.) is an important agronomic trait. Two segregating populations with N22 (indica) as a common parent, viz. a set of 122 backcross-inbred lines (BILs) derived from the backcross Nanjing35 (japonica)/N22//Nanjing35 and another population comprising 189 recombinant inbred lines (RILs) from the cross of USSR5 (japonica) and N22, were studied to detect quantitative trait loci (QTL) controlling seed storability. Germination percentage (GP) was used to evaluate seed storability after aging treated under three different conditions, viz. natural, artificial and combined aging treatments. A total of seven QTLs were identified on chromosomes 1, 2, 5, 6 and 9. Among them, a major QTL, qSSn-9, was common in the two populations. In contrast, four QTLs (qSSnj-2-1, qSSn-2-2, qSSn-5 and qSSn-6) were detected in BILs and the QTL qSSn-1 was identified in RILs, which was a new QTL for seed storability. The N22-derived alleles increased the seed storability at all the loci except qSSnj-2-1. We also investigated the effect of QTLs using five selected lines with high storability from BILs and verified qSSn-5 with a near-isogenic line (NIL). These results provide an opportunity for pyramiding or map-based cloning major QTLs for seed storability in rice. 相似文献
107.
Shinjiro Kanazawa Ngo Thi Tuong Chau Shintaro Miyaki 《Soil Science and Plant Nutrition》2005,51(5):671-674
From acidic tea soils of Kagoshima Prefecture in Japan, some soil properties were determined and 38 strains of acid tolerant microorganisms were isolated. Different Al3+ concentrations were applied to YG media to estimate Al resistance. Selected microbial strains could grow strongly in the liquid media in the presence of 100 mM Al3+ and survive even in 300 mM Al3+ at pH 3.0. Their base sequences of 28S rDNA-D1/D2 were determined and sequence data were searched using the Basic Local Alignment Search Tool (BLAST) system. The results of sequencing revealed that the isolates belong to two different species, Cryptococcus sp. and Candida palmioleophila. When cultivated with various Al3+ concentrations, the yeast growth was inhibited at a concentration of 200 mM. Pre-cultivation of these strains with 0–30 mM Al3+ did not promote the growth response caused by Al3+ . Inductively-Coupled Plasma-Mass Spectrometry (ICP-MS) was used to assess the elimination of Al. The amount of Al remaining in culture media was decreased considerably after cultivation. Due to a capacity for resistance to significant Al concentrations as well as high Al elimination, these acid tolerant and Al resistant yeasts may have potential applications in the bio- and phyto-remediation of Al and acid-contaminated soils. 相似文献
108.
Jerome L. Mahloch 《Water, air, and soil pollution》1974,3(2):217-236
Management of our nation's water resources through planning and control of water pollution hinges on the availability and interpretation of water quality data on which to base management decisions. This paper is aimed at exploring graphical methods which allow rapid and informative analysis of water quality data. The graphical methods presented in this paper fall into two main categories. The first category relates to graphical procedures which are developed as part of a statistical test, such as discriminant analysis. The second category involves approximation of multivariate water quality data into two dimensions. The methods for accomplishing the latter are canonical decomposition and high-dimensional plotting. Each of these methods is developed and used on an example set of data to demonstrate their utility. These methods seek to not only present a graphical representation of the data, but also to explain variations and interrelationships within the data itself. 相似文献
109.
The concentrations of, and deposition rates for, the pollutant metals (Pb, Cu, Zn, Ni, and Cd) and the rare earth elements are reported for the sediments and settling particulates in a large, remote lake (Lake Opeongo) in the Algonquin Provincial Park, Ontario. Using a mass conservation model based on the rare earth elements, it is estimated that only 40 to 60% of pollutant metals getting into the lake is retained by the sediments. The low retention anada rate may explain the widely reported intra-basin and intra-lake differences in metal contents of sediments and casts some doubt on the use of pollutant metal profiles in retrospective assessment of the human contribution to the metal flux into many lake basins. 相似文献
110.