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991.
Sung-Mo Kang Myeung-Won Cho Kwon-Min Kim Dong-yeop Kang Won-Mo Koo Kyu-Hyeok Kim Jong-Young Park Sung-Suk Lee 《Wood Science and Technology》2012,46(4):643-656
Supercritical fluid (SCF) impregnation is a promising preservative treatment method for wood. In order to commercialize the sub- and supercritical CO2 biocide treatment, better understanding of the fluid phase and its effect on treatment results have to be demonstrated and developed. Preservative treatability under super- and subcritical fluid conditions was evaluated using radiata pine sapwood, and treating characteristics in relation to different fluid phases and treatability were discussed. Various treatment conditions resulted in varying biocide retentions and distributions. Higher pressure conditions enhanced biocide retentions resulting from increasing biocide input in the applied saturation method. Subcritical CO2 condition produced higher biocide retentions and little retention gradients from face to core. Subcritical CO2 treatment has a couple of benefits such as investment costs and energy consumption compared with supercritical CO2. 相似文献
992.
Estimating water footprint of paddy rice in Korea 总被引:1,自引:0,他引:1
The purpose of this article is to examine the issues of low grain self-sufficiency and the high portion of agricultural water use in South Korea, and to trace the water footprint (WF) of rice products. In this study, different types of water use were described as green, blue, and gray WFs and were analysed using suitable estimation methods to determine irrigation water requirements in South Korea. Virtual water (VW) import and export of rice product were calculated based on international trade statistics during 2004–2009, and the WF of the national consumption was estimated. The WF of rice was 844.5 m3/ton, and green, blue, and gray water accounted for 294.5, 501.6, and 48.4 m3/ton, respectively. The VW import and export were 404.17 and 2.03 Mm3/year, respectively, against an import 199.5 times that of the export. Three countries (China, USA, and Thailand) accounted for over 95 % of the total VW imports of rice products into South Korea. The total WF was 5,712.08 Mm3/year, thus the WF per capita for rice was estimated at 118.1 m3/year. The internal WF of rice consumption was 5,308.05 Mm3/year, and the external WF was 404.03 Mm3/year. The WF of total agricultural water use should be analyzed for sustainable agricultural production and water management, and these results should be applied in establishing long-term policies for agricultural water resources. 相似文献
993.
Production of blastocysts after intergeneric nuclear transfer of goral (Naemorhedus goral) somatic cells into bovine oocytes 总被引:1,自引:0,他引:1
Oh BC Kim JT Shin NS Kwon SW Kang SK Lee BC Hwang WS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(11):1167-1171
Interspecies cloning may be a useful method to help conserve endangered species and to study nuclear-cytoplasm interaction. The present study investigated in vitro development of goral (Naemorhedus goral) intergeneric nuclear transfer embryos produced by fusing goral fibroblasts with enucleated metaphase II (MII) bovine oocytes. After two to five passages, serum-starved or non-starved goral skin fibroblast cells were transferred into enucleated MII bovine oocytes. Couplets were electrically fused and chemically activated, and then cultured in either modified synthetic oviduct fluid (mSOF) or tissue culture medium-199 (TCM-199) supplemented with 10% FBS. Serum starvation of donor cells did not affect the fusion rate and or development to of cells to the two-cell stage, to more than 9-cells, or to morulae, regardless of culture medium. Three blastocysts from 202 fused embryos were obtained when embryos reconstructed with non- serum- starved donor cells were cultured in mSOF. However, no blastocysts were obtained when the embryos reconstructed with serum-starved donor cells were cultured in mSOF. The total cell number of goral intergeneric embryos averaged 130.3 (range 105-180). In conclusion, this study demonstrated that bovine oocytes can support blastocyst development after intergeneric SCNT with goral fibroblasts. 相似文献
994.
试验旨在研究饲粮不同赖氨酸水平对早期断奶仔猪生产性能的影响。选择28日龄断奶、平均初始体重(6.74±0.03)kg的杜长大三元杂交仔猪150头,随机分为3组,每组2个重复(圈),每个重复25头猪,分别饲喂总赖氨酸水平为1.35%、1.42%、1.60%的3种饲粮,饲养试验时间为20d。结果表明,各项生产性能指标均随饲粮总赖氨酸水平提高呈二次曲线变化。以处理Ⅱ(总赖氨酸水平1.42%)为最佳,随着赖氨酸水平的降低或升高,生产性能均下降。当总赖氨酸水平提高到1.60%(处理Ⅲ)时,其日增重、日采食量和每克赖氨酸增重均显著低于处理Ⅱ(P0.05)。 相似文献
995.
996.
In a preceding study, complete substitution of fish meal protein with cottonseed meal (CM) protein did not affect the survival or growth rate of adult rainbow trout over a 6-mo period. Gossypol, a naturally occurring compound in cottonseeds, has an antifertility effect in terrestrial animals, but information regarding salmonid fish is lacking. Female rainbow trout in this experiment were fed diets with either 0, 25, 50, 75, or 100% (diets 1 to 5) of the fish meal protein replaced with CM protein until first maturation and spawning to study long-term effects on growth and reproduction. Feeding diets containing CM over a total period of 10 mo did not result in differences in growth and mortality compared to the control group (P > 0.05). Increased CM incorporation levels resulted in decreased (P < 0.05) blood hemoglobin (10.6 +/- 1.3, 8.4 +/- 1.8, 7.3 +/- 1.1, 6.9 +/- 0.8, and 5.6 +/- 1.4 g/dL) and hematocrit (49.6 +/- 3.9, 38.5 +/- 9.3, 34.4 +/- 3.7, 34.8 +/- 4.9 and 28.0 +/- 6.8%) levels in diets 1 to 5, respectively. The CM incorporation level had no effect (P > 0.05) on the number of eggs produced per female but led to a reduction (P < 0.05) in egg weight. Eyed stage survival of embryos was low in all dietary groups and did not show differences (P > 0.05). However, an increasing CM incorporation level led to a linear increase (P < 0.05) in the number of females that produced no viable embryos (23.1, 37.5, 42.9, 60.0, and 71.4%). Gossypol in the diet was absorbed by the female trout and transferred to the eggs (0, 2.2 +/- 0.5, 6.7 +/- 1.6, 10.6 +/- 4.2, and 20.0 +/- 2.6 micrograms/g in diets 1 to 5, respectively). A high concentration of gossypol remained in the juveniles at the swim-up stage (endogenous yolk-absorbed) (0.6 +/- 0.3, 2.4 +/- 0.3, 3.4 +/- 0.0, and 4.7 +/- 1.0 micrograms/g, diets 2 to 5, respectively). The findings suggest that replacement of the dietary fish meal protein with CM protein has no effect on fish growth and mortality but may lead to a reduction in reproductive performance in female rainbow trout. 相似文献
997.
Don D. Wanasinghe 《Acta veterinaria Scandinavica》1981,22(1):109
Using a simple in vitro test it was demonstrated that staphylococci, Streptococcus agalactiae, and micrococci, the species of bacteria which are commonly isolated from udder infections, adhered to mammary gland epithelial cells readily and in large numbers. Some strains of organisms which are associated with sporadic outbreaks or occur less commonly, like Str. dysgalactiae and Str. uberis, adhered moderately. Escherichia coli, Klebsiella spp., Corynebacterium pyogenes, C. bovis, Str. bovis, and Str. faecalis, species which are isolated occasionally, adhered poorly. From these studies, it appears that selective adherence of bacteria to the epithelial cells is a factor contributing to the ability of organisms to infect the mammary gland and may, therefore, be considered an important stage in the pathogenesis of bovine mastitis. 相似文献
998.
Two adult male labrador dogs had short clinical histories of congestive cardiac failure lasting only six weeks. Cardiac function deteriorated rapidly in both dogs, in spite of symptomatic treatment with cardiac glycoside, diuretic and p-adrenergic blocker. Necropsies revealed ascites and pulmonary congestion, but no macroscopic evidence of valvular or myocardial disease adequate to account for the cardiac dysfunction. Both dogs had extensive stenosis of extramural coronary arteries. This unusual vascular lesion comprised fibroelastic intimal thickening, discontinuity of internal elastic lamella and focal atrophy of medial smooth muscle. It seems likely that cardiac failure in these dogs was associated with myocardial underperfusion caused by extensive non-thrombotic, non-atherogenic stenosis of extramural coronary arteries. 相似文献
999.
Ji-Hoon Kim Won Sik Shin Dong-Ik Song Sang June Choi 《Water, air, and soil pollution》2005,166(1-4):367-380
Single- and bi-solute sorption and desorption of 2,4-dichlorophenol (2,4-DCP) and 2,4,5-trichlorophenol (2,4,5-TCP) in montmorillonite modified with hexadecyltrimethylammonium (HDTMA) were investigated using multi-step sorption and desorption procedure. Effect of pH on the multi-step sorption and desorption was investigated. As expected by the magnitude of octanol-water partition coefficient, K ow , both sorption and desorption affinity of 2,4,5-TCP was higher than that of 2,4-DCP at pH 4.85 and 9.15. For both chlorophenols, the protonated speciation (at pH 4.85) exhibited a higher affinity in both sorption and desorption than the predominant deprotonated speciation (about 95% and 99% of 2,4-dichlorophenolate and 2,4,5-trichlophenolate anions at pH 9.15, respectively). Desorption of chlorinated phenols was strongly dependent on the current pH regardless of their speciation in the previous sorption stage. Freundlich model was used to analyze the single-solute sorption and desorption data. No appreciable desorption-resistant (or non-desorbing) fraction was observed in organoclays after several multi-step desorptions. This indicates that sorption of phenols in organoclay mainly occurs via partitioning into the core of the pseudo-organic medium, thereby causing desorption nearly reversible. In bisolute competitive systems, sorption (or desorption) affinity of both chlorophenols was reduced compared to that in its single-solute system due to the competition between the solutes. The ideal adsorbed solution theory (IAST) coupled to the single-solute Freundlich model successfully predicted bisolute multi-step competitive sorption and desorption equilibria. 相似文献
1000.
Establishment of reference ranges and evaluation of in vitro concentration‐dependent platelet inhibition by acetylsalicylic acid for multiple electrode impedance aggregometry in healthy dogs 下载免费PDF全文
J. M. Haines P. M. Lee R. M. Hegedus J. K. Hwang M. H. Court 《Journal of veterinary pharmacology and therapeutics》2017,40(6):618-628
Acetylsalicylic acid (ASA, aspirin) is an antiplatelet medication used for prevention of thromboembolism. Effects of ASA appear to vary widely between dogs, but the underlying mechanisms are not understood. The Multiplate analyzer is a newer form of whole‐blood impedance aggregometry recently validated for use in healthy dogs. A method utilizing this instrument to measure ASA effects on platelet function has not been established. The goals of this study were to establish reference ranges for the Multiplate in healthy dogs and secondly, to develop a technique to determine the in vitro concentration of ASA needed to cause 50% inhibition of platelet aggregation (IC50). Reference ranges established from 40 dogs at multiple test times for three agonists were consistent with previously published values. In vitro IC50 values were calculated using the sigmoid Emax model in 20 healthy dogs on two occasions to determine individual repeatability. Calculated in vitro IC50 demonstrated four ASA response groups: responder (n = 16), poor responder (n = 1), variable responder (n = 2), and nonresponder (n = 1). Multiplate within‐assay variability was <10% for area under the curve (AUC), and between‐assay baseline AUC variability was <15%. The described technique allowed for determination of an in vitro IC50 for ASA in dogs using a multiple electrode impedance aggregometer. 相似文献