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991.
Assessing hygiene proficiency on organic and conventional pig farms regarding pork safety: A pilot study in Finland 总被引:1,自引:0,他引:1
K.-M. Siekkinen L. Nuotio J. Ranta R. Laukkanen S. Hellstrm H. Korkeala R. Maijala 《Livestock Science》2006,104(1-2):193-202
A key element in the EU Common Agricultural Policy (CAP) will be a single farm payment system that is linked to compliance with rules on, for instance hygiene standards. However, there are no recommended methods for assessing the hygiene proficiency of pig production farms. The present study was undertaken to develop a method for this purpose. A first implementation was done on pilot scale; with a set of both conventional and organic pig farms (N = 15). Fifty hygiene-related factors were selected, especially with reference to the possible proliferation of enteric pathogens Listeria monocytogenes, Yersinia enterocolitica and Yersinia pseudotuberculosis. The factors were allocated into 8 evaluation categories: (1) general production management, (2) animal density, (3) the outdoor area for pigs, (4) pest and pet animals, (5) general hygiene in the piggery, (6) pen hygiene, (7) feed production hygiene, and (8) feeding hygiene. A farm questionnaire and a supplementary on-site observation form were devised, and one arbitrary scale of hygiene points assigned for each factor. In addition to the mailed questionnaires, one person subsequently visited all the farms, perused the questionnaire with the owners and completed the observation form. The hygiene scores of the farms in each evaluation category were compared both without weighting and with weighting based on expert opinions. The method proved to be feasible and applicable to different types of production. 相似文献
992.
Perea F Soto E Hernández H González D Palomares R De Ondiz A González C 《Tropical animal health and production》2006,38(4):353-363
The aim of this study was to examine the monthly variation of the first service conception (FSC) and oestrus frequency (OF)
from 8308 artificial inseminations (AI) of 2960 crossbred dual-purpose cows on three commercial farms with improved management
located in the Maracaibo Lake Basin, Venezuela. The effects of month of the year, agroecological area (from dry tropical forest
to sub-humid tropical forest on the three farms), predominant breed (BT, Bos taurus; BI, Bos indicus), and season (December–April}; May–August; and September–November) were considered. Data were analysed using logistic regression
(FSC) and GLM (OF) from SAS. The mean FSC was 55.4% overall and 48.7%, 57.0% and 58.3% for farms A, B and C, respectively
(p < 0.01). Within the three agroecological areas (farms A, B and C), the FSC was highest during the cooler and drier months
of the year (season 1), while the lowest FSC was obtained during the months of highest rainfall and humidity (season 3) (53.3%
vs 37.4%; 58.5% vs 49.0% and 63.0% vs 52.3% on farms A, B, C, respectively; p < 0.01). In the three studied farms, OF was
higher during the first 4 months of the year; with a diminishing trend towards the end of the year (p % 0.05). In general,
BI cows had a higher FSC than BT cows, especially during the second half of the year, when environmental conditions were characterized
by higher rainfall and humidity with lower wind velocity (58.8%a 55.5%b and 46.4%c in season 1, 2 and 3 respectively; a, b, c p < 0.01). 相似文献
993.
Miller DL Taylor SK Rotstein DS Pough MB Barr MC Baldwin CA Cunningham M Roelke M Ingram D 《Veterinary research communications》2006,30(3):307-317
This study documents the seroprevalence of feline immunodeficiency virus (FIV) and puma lentivirus (PLV) in free-ranging and
captive Florida panthers (Puma concolor coryi) (n = 51) and translocated Texas cougars (P. concolor stanleyana) (n = 10) from 1985 to 1998. The sera were tested for anti-FIV antibodies by enzyme-linked immunosorbent assay (ELISA) and Western
blot tests. The ELISAs were read kinetically (KELA) and the sera were retrospectively examined by PLV peptide ELISA. Eleven
panthers and one cougar were positive by KELA; 4 panthers and 4 cougars were equivocal; 35 panthers and 5 cougars were negative;
and 1 panther had no data. Seven of the 11 KELA-positive panthers were also positive by Western blot tests and all but one
were positive by PLV peptide ELISA. Ten KELA-negative and Western blot-negative cats, were positive by PLV peptide ELISA.
KELA results varied within cats from one sample period to the next, but PLV peptide ELISA results were consistent. Territorial
sympatry and mating behaviour, noted from radiotelemetry location data on the cats, may have contributed to viral transmission
between seropositive animals. These findings suggest that Florida panthers and the introduced Texas cougars have been exposed
to FIV and/or PLV. 相似文献
994.
James M Barron Ronald G Twibell Heidi A Hill Kyle C Hanson Ann L Gannam 《Aquaculture Research》2016,47(12):3899-3906
The Pacific lamprey Entosphenus tridentatus is an ancestral species of critical importance to the ecosystem and indigenous cultures in the Pacific Northwest. Conservation aquaculture has been proposed as a potential technique to restore Pacific lamprey populations. Intensive culture methods and diets for this species have not been developed. A sixteen week feeding trial tested the effects of seven diet treatments on the survival, growth, fatty acid profile and whole body lipid content of Pacific lamprey ammocoetes. Dietary treatments were: active dry yeast, yeast plus fish oil emulsion, micro‐algae, micro‐algae plus fish oil emulsion, yeast with micro‐algae, yeast with micro‐algae plus fish oil emulsion and yeast with larval fish diet. Each diet was offered to five replicate tanks stocked with 20 ammocoetes that were 51 days post hatch. Survival during the trial was not affected by diet. The greatest length and weight increases were in fish fed diets containing yeast. Growth decreased as the amount of algae in the diet was increased. Lipid retention was significantly higher in fish fed yeast with larval fish diet relative to the other treatments. Feed conversion ratio was lowest in fish fed diets containing yeast. Whole body fatty acid profiles tended to reflect the fatty acid profile of the diet. Percentages of 20:5n‐3 and 22:6n‐3 were significantly higher in fish fed diets containing fish oil emulsion. Overall, yeast with larval fish diet provided the best growth performance in larval Pacific lamprey. 相似文献
995.
Response and effect traits of arable weeds in agro‐ecosystems: a review of current knowledge 下载免费PDF全文
S Gaba R Perronne G Fried A Gardarin F Bretagnolle L Biju‐Duval N Colbach S Cordeau M Fernández‐Aparicio C Gauvrit S Gibot‐Leclerc J‐P Guillemin D Moreau N Munier‐Jolain F Strbik X Reboud 《Weed Research》2017,57(3):123-147
Integrating principles of ecological intensification into weed management strategies requires an understanding of the many relationships among weeds, crops and other organisms of agro‐ecosystems in a changing context. Extensively used during the last two decades in weed science, trait‐based approaches have provided general insights into weed community response to agricultural practices, and recently to understanding the effect of weeds on agro‐ecosystem functioning. In this review, we provide a holistic synthesis of the current knowledge on weed response and effect functional traits. Based on the literature and recent advances in weed science, we review current knowledge on (i) weed functional groups and ecological strategies, (ii) weed functional response traits to cropping systems and (iii) weed functional effect traits affecting agro‐ecosystem functioning. For each functional trait, we explicitly present the assumptions and evidence on the linkage between trait values and ecological functions, in response to either management practices, for example tillage, sowing and herbicides, or biotic interactions, for example crop–weed competition and pollination. Finally, we address and discuss major research avenues that may significantly improve the use of traits and the knowledge of functional diversity in weed science for the future, especially to design and implement more environmentally sustainable weed management strategies. 相似文献
996.
997.
Update on the 35‐year expansion of the invasive root pathogen,Phytophthora lateralis,across a landscape of Port Orford cedar (Chamaecyparis lawsoniana) 下载免费PDF全文
Port Orford cedar (Chamaecyparis lawsoniana) is endemic to northern California and southwestern Oregon and is considered a foundation species that plays critical roles in riparian areas and on nutrient‐poor soils. Since 1952, a non‐native, pathogenic oomycete (Phytophthora lateralis) has been spreading throughout the range of the cedar. Most spread occurs by vehicles carrying infested soil along gravel roads primarily used for timber harvest. In a previous study conducted in 1998 and 1999, Port Orford cedar and P. lateralis were censused in a 37‐km2 study area and dendrochronology was used to reconstruct the history of pathogen invasion. That work, which represents the only detailed analysis of spread rates for P. lateralis, showed that the first successful invasion into the study area took place in 1977 and that 43% of the susceptible host sites (stream crossings) were infested by 1999. In the work presented here, all sites that were uninfested in 1999 were re‐censused in 2012, extending the historical reconstruction of P. lateralis spread to 35 years. Two new infestations were initiated between 1999 and 2012, suggesting that the rate of spread of P. lateralis has slowed greatly. Between 1980 and 1989, the average number of new site infestations was 1.8 infestations per year, while between 1990 and 1999 the average was 0.4 infestations per year and between 2000 and 2009 the average was 0.2 infestations per year. Several potential explanations for the reduced number of new infestations are discussed. 相似文献
998.
Guangjun Guo Jianchang Gao Xiaoxuan Wang Yanmei Guo J.C. Snyder Yongchen Du 《Breeding Science》2013,63(3):239-245
An accurate and simple evaluation method is crucial for identifying whitefly resistance in tomato breeding. We developed an in vitro method for evaluating resistance of tomato leaves and tested this on wild and cultivated tomato varieties. We found that young leaves observed for whitefly oviposition after 8 hours provided appropriate comparative conditions. This method effectively distinguished resistance among tomato cultivars and wild species and also demonstrated significant difference in oviposition rates among leaf positions on susceptible cultivars. The in vitro test was as precise as in vivo test using intact plants and had advantages over in vivo test, and can be used for evaluating resistance in large populations. 相似文献
999.
1000.
Douglas C. Doehlert Jae‐Bom Ohm Michael S. McMullen Neil R. Riveland 《Cereal Chemistry》2009,86(2):239-246
Test weight and groat proportion are two very important quality characteristics of oat grain. In this study, we pose the hypothesis that these two characteristics are related through characteristics of grain density. Test weight is defined as the product of kernel density and packing proportion. Groat proportion, in theory, is the ratio of the groat mass to the kernel mass. We present two theoretical constructions expressing test weight in terms of groat proportion, packing proportion and kernel density components. To test these, we have applied measurements of test weight, groat proportion, kernel density components, and packing proportion of 18 oat cultivars grown at six environments. Whereas the groat proportion alone accounted for only 34% of the variation in test weight, our theoretical constructions that included groat proportion could account for ≤82% of variation in test weight. Also, we present previously undescribed variation in oat kernel density components across genotypes and environments. Although the kernel density alone could account for most of the variation in test weight across genotypes, packing proportion appeared to be more important in describing variation in test weight of a genotype across different environments. We observed significant variation in both groat and hull density which, together with groat proportion, described most of the variation in kernel density. 相似文献