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941.
Performances of Pinus taxa were studied to 10 years of age in two trials in each of Misiones and Entre Ríos provinces across the Mesopotamia region of Argentina. Taxa comprised 22 populations from sources in Argentina, Australia, Brazil and Zimbabwe including Pinus elliottii var. elliottii (Pee), Pinus caribaea var. hondurensis (Pch), their four, inter-specific hybrids (F1, F2 and backcrosses from F1 to Pch and to Pee—all as broadly based bulks); other Pee and Pinus taeda (Pt) comprised narrower or unspecified bulks. Variable numbers of taxa were missing at each site. Mean survival across sites at age 10 years ranged 53.2–91.3% averaging 74.2%. Analysis of variance of plot means indicated population effect was statistically significant (p < 0.05) for all or most growth and quality traits at all sites. However, significant differences from the nominated check seedlot at the Entre Ríos sites (Pee, Australia) were extremely rare, while quite common at the northern, Misiones sites (check seedlot a Pt population). In the Misiones trials, F1, F2 and both backcross hybrids showed better stem straightness than Pee and Pt from Argentina, generally with statistically significant differences (p < 0.05). Pt showed lowest forking scores (desirable). Taxon × environment interaction was statistically significant (p < 0.01) for growth traits only (p > 0.05). However, this interaction contributed an average of only 34.1% of the taxon variance suggesting a lack of practical importance. Taxa most suitable for deployment in the Mesopotamia region, Argentina are suggested. 相似文献
942.
Nantaprapa Nantiyakul Samuel Furse Ian D. Fisk Gregory Tucker David A. Gray 《Journal of Cereal Science》2013
In this paper, we demonstrate a novel and environmentally-conscious approach to the isolation of oil bodies (OBs) from the bran arising from the milling of Oryza sativa (Basmati rice). We have used several physical techniques to determine the effect of the steps of the process on the OBs, and describe an isolation process that is scalable to an industrial level. The physical techniques [microscopy, particle size determination (diameter 1.9–5.8 μm), ζ-potential (−40 mV at pH 8.0, 0 mV at pH 4.0, 17 mV at pH 2.0), and relative turbidity measurements (pH 3.0–5.0 unstable, pH 6.0–8.0 stable)] and chemical analyses (lipid 83.7%, protein 11.5% dry basis) also give us an insight into the physical properties of OBs in general. This understanding has implications for the use of OBs in food manufacturing, and on the isolation of OBs from a variety of cereal crops. 相似文献
943.
944.
André M. Crespilho Beth E. Spizziri Mindy Meyers James K. Graham 《Journal of Equine Veterinary Science》2013
Cooled stallion semen has a short viable life, which ranges with acceptable motility and viability from 24 up to 48 hours. The purpose of this study was to compare the effects of storage pH, the ability of three different zwitterionic buffers, and cholesterol-loaded cyclodextrins (CLC) to preserve the motility and integrity of stallion sperm cooled to 5°C for 48 hours. Fourteen ejaculates were collected and split to receive CLC or not (control group). After incubation, each sample was split into six subsamples and diluted in KMT extender containing 4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES), N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES), or 2-(N-morpholino)ethanesulfonic acid (MES) buffers, and the final pH was adjusted to either 7.0 or 6.6, totalizing 12 experimental groups as a function of CLC, buffer, and pH variables (2 × 3 × 2 factorial). The motility parameters and integrity of plasma and acrosome membranes (live cell index) were determined using computer-automated semen analysis and epifluorescence microscopy at 3, 6, 24, and 48 hours of cooling period. According to results, pH was not a significant source of variation for motility and live sperm over different cooling periods. However, samples diluted in BES exhibited higher progressive motility within 3 hours and higher percentages of total motile cells after 48 hours of incubation at 5°C (P < .05). After 24 hours of storage, CLC-treated sperm samples presented higher motility than control group (P < .05), and after 48 hours of incubation, CLC-treated sperm exhibited higher percentages of live, motile, and progressively motile sperms (P < .05). We inferred that equine semen diluted in KMT containing BES as buffer and CLC treatment improve the equine sperm survival during storage at 5°C for 48 hours. 相似文献
945.
946.
Julian R. Mateus-Rodriguez Stef de Haan Jorge L. Andrade-Piedra Luis Maldonado Guy Hareau Ian Barker Carlos Chuquillanqui Victor Otazú Rebeca Frisancho Carolina Bastos Arione S. Pereira Carlos A. Medeiros Fabian Montesdeoca Jacqueline Benítez 《American Journal of Potato Research》2013,90(4):357-368
Producing large quantities of high quality mini-tubers at low cost is essential for an economically viable supply of seed potatoes. Here we systematize the technical and economic aspects of aeroponics and provide a benchmark comparison of this technology with other mini-tuber production systems as developed in Latin America: conventional, semi-hydroponics, and fiber-cement tiles technology. Research methodologies included: 3-year registration of cash flows and production registers of aeroponics, economic and technical surveys, in-depth inquiry with managers of technologies. Results show that aeroponics as promoted by the International Potato Center (CIP) has several advantages, including high multiplication rates (up to 1:45), high production efficiency per area (> 900 mini-tubers per m2), savings in water, chemicals and/or energy, and positive economic indicators. The fiber-cement tiles technology from Brazil is also shown to be highly efficient and slightly more robust compared to aeroponics. Preconditions for the successful adoption of the different technologies in developing countries are discussed. 相似文献
947.
Carrie J. Lavers Shawn L.B. McKenna Ian R. Dohoo Herman W. Barkema Greg P. Keefe 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(11):1053-1060
This study evaluated test characteristics of environmental culture (EC) for the detection of Mycobacterium avium subspecies paratuberculosis (MAP) in 32 herds over a 2-year period. Individual fecal samples were collected every 6 mo and environmental samples every 3 mo. Individual fecal culture was performed on samples from positive pools. Samples were cultured in broth, with confirmatory polymerase chain reaction performed on positive fecal samples. Repeated measures were accounted for using GEE logistic models. Relative to a MAP herd-status based on all pooled fecal culture results collected during the study, sensitivity of a set of 6 EC-samples collected from prescribed locations within the herd environment (EC-6) was 71% [95% confidence interval (CI): 49% to 86%] and specificity was 99% (95% CI: 95% to 100%). Sensitivity of EC increased as apparent within-herd fecal culture prevalence (aWHP) increased. The estimated aWHP increased as the proportion of positive EC-samples within an EC-6 set increased. Environmental culture is an acceptable tool for herd diagnosis of MAP in low-prevalence herds. 相似文献
948.
Laura A. Nafe Ian D. Robertson Eleanor C. Hawkins 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(10):955-959
This study aimed to determine the frequency of cervical lung lobe herniation (CLLH) in dogs evaluated fluoroscopically and to identify associated characteristics. Reports of diagnostic procedures and patient summaries from 2008 to 2010 were reviewed retrospectively. Signalment, body weight, duration of cough, presence of heart murmur and airway collapse, and radiographic findings were compared between dogs with and without CLLH. Of the 121 dogs that were examined, CLLH occurred in 85 (70%). The extra-thoracic trachea kinked during herniation in 33 (39%) dogs with CLLH. Collapse of the intra-thoracic trachea (assessed fluoroscopically or bronchoscopically) and collapse of major bronchi (assessed fluoroscopically) were strongly associated with CLLH. Although redundant dorsal tracheal membrane on radiographs was associated with CLLH, extra-thoracic tracheal collapse, assessed fluoroscopically or bronchoscopically, was not. No other associations were found. Cervical lung lobe herniation was present in most dogs evaluated during cough and was associated with intra-thoracic large airway collapse, but not duration of cough. 相似文献
949.
Abstract Extract Tutu (Coriaria arborea Lindsay) is a small tree or shrub, variable in height, with leaves lin. to 3in. long, oblong and sessile, which has many flowers in long, drooping racemes. The fruit is purplish-black and is enveloped by juicy, persistent, and enlarged petals. It is a shrub that is found abundantly on certain river banks, bush, scrub, and tussock grassland throughout New Zealand (Connor, 1951). The green fruit and associated racemes, and also the flowering racemes, are highly toxic. The ripe fruit is relatively not as toxic (Easterfield, 1901). 相似文献
950.
K. M. Jones B. Graham Sally A. Bound M. J. Oakford 《The Journal of Horticultural Science and Biotechnology》2013,88(1):139-147
Trials in southern Tasmania examined the thinning effects of ethephon on ‘Gala’ and ‘Jonagold’ apples. Untreated controls were compared with ethephon thinning sprays applied at full bloom at 50,100,200,400,800 and 1 600 mg I“1 to both cultivars. Thinning of both cultivars was related to the concentration of the spray and in most cases logistic models were fitted. Thinning effectiveness was largely reflected in increased fruit weight and size. The ‘Gala’ fruit was still not large enough for Australian markets. Ethephon at 200 mg I“1 effectively thinned ‘Jonagold’ and produced the required increases in fruit size and weight. ‘Jonagold’ was overthinned by the high concentrations of ethephon, but this was not reflected in increased fruit weight and size. Ethephon also reduced vegetative growth at the higher concentrations which was considered an advantage. More work is required to establish specific recommendations for either cultivar. 相似文献