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51.
Fenbendazole in ground feed was fed on 3 successive days at the rate of 3 mg/kg of body weight to 15 sows naturally infected with kidney worm (Stephanurus dentatus). Fifteen similar sows were used as nontreated controls. A total of 49 kidney worms were recovered from daily urine samples collected from 10 of the 15 treated sows within 5 days after the 3rd dose of treatment. One control sow passed 10 kidney worms on the 2nd and 3rd days. Urine samples from treated sows became negative for kidney worm eggs by the 5th to 12th posttreatment days, except for urine samples from 1 sow that contained a few eggs on the 12th day and another sow that contained a few eggs on the 19th and 33rd posttreatment days. Urine samples from control sows contained approximately the same number of kidney worm eggs in the posttreatment period as earlier. Compared with that in control sows, the hatchability of the parasite eggs from treated sows was greatly reduced. Kidney worms were not recovered at necropsy from the treated sows and a total of 860 kidney worms were recovered from the control sows (57 av). 相似文献
52.
Gerber V Straub R Marti E Hauptman J Herholz C King M Imhof A Tahon L Robinson NE 《Equine veterinary journal》2004,36(7):576-582
REASONS FOR PERFORMING STUDY: Endoscopic scoring of airway mucus quantity and quality has not been critically assessed. OBJECTIVES: To evaluate mucus scores for 1) observer- and horse-related variance and 2) association with inflammation, mucus viscoelasticity and measured volume. METHODS: Variance of scoring within and between observers and over time within horses were determined for airway mucus accumulation, apparent viscosity, localisation and colour, and correlations of mucus accumulation scores with neutrophil ratios in secretions. The relationship of accumulation score to measured volumes of 'artificial mucus' was investigated. Correlations of mucus accumulation, apparent viscosity and colour scores with measured viscoelasticity were tested. Viscoelasticity was compared between tracheal secretion samples collected ventrally and dorsally. RESULTS: Mucus accumulation scoring showed excellent interobserver agreement and moderate horse-related variance, was related to measured volumes of 'artificial mucus', and correlated well with neutrophilic airway inflammation. Scores of mucus viscosity, colour and localisation showed high observer-related variance. Mucus accumulation, apparent viscosity and colour scores did not correlate with measured tracheal mucus viscoelasticity, but dorsally-localised mucus showed 2-fold higher measured viscoelasticity than ventrally-localised samples. CONCLUSIONS: Mucus accumulation scores are a reproducible measure of mucus volumes in the trachea. POTENTIAL RELEVANCE: Endoscopic scoring of mucus accumulation is a reliable clinical and research tool. In contrast, apparent viscosity, localisation and colour scores should be interpreted with caution. 相似文献
53.
Ana M Lopes Sara Marques Eliane Silva Maria J Magalh?es Ana Pinheiro Paulo C Alves Jacques Le Pendu Pedro J Esteves Gertrude Thompson Joana Abrantes 《Veterinary research》2014,45(1)
Rabbit hemorrhagic disease virus (RHDV) is a highly lethal Lagovirus, family Caliciviridae, that threatens European rabbits (Oryctolagus cuniculus). Although a related virus severely affects hares, cross-species infection was only recently described for new variant RHDV in Cape hares (Lepus capensis mediterraneus). We sequenced two strains from dead Iberian hares (Lepus granatensis) collected in the 1990s in Portugal. Clinical signs were compatible with a Lagovirus infection. Phylogenetic analysis of the complete capsid gene positioned them in the RHDV genogroup that circulated on the Iberian Peninsula at that time. This is the earliest evidence of RHDV affecting a species other than European rabbits. 相似文献
54.
To establish infection in the host, malaria parasites export remodeling and virulence proteins into the erythrocyte. These proteins can traverse a series of membranes, including the parasite membrane, the parasitophorous vacuole membrane, and the erythrocyte membrane. We show that a conserved pentameric sequence plays a central role in protein export into the host cell and predict the exported proteome in Plasmodium falciparum. We identified 400 putative erythrocyte-targeted proteins corresponding to approximately 8% of all predicted genes, with 225 virulence proteins and a further 160 proteins likely to be involved in remodeling of the host erythrocyte. The conservation of this signal across Plasmodium species has implications for the development of new antimalarials. 相似文献
55.
Atomic force microscopy of an organic monolayer 总被引:2,自引:0,他引:2
O Marti H O Ribi B Drake T R Albrecht C F Quate P K Hansma 《Science (New York, N.Y.)》1988,239(4835):50-52
Atomic force microscope images of polymerized monolayers of n-(2-aminoethyl)-10,12-tricosadiynamide revealed parallel rows of molecules with a side-by-side spacing of approximately equal to 0.5 nanometer. Forces used for imaging (10(-8) newton) had no observable effect on the polymer strands. These results demonstrate that atomic force microscope images can be obtained for an organic system. 相似文献
56.
The spallation krypton data from rock chip 15555,23 indicate a wellshielded location during most of the time during which the rock was exposed to cosmic rays. A krypton-krypton exposure age of 81(+17)(-7) x 10(6) years is calculated, and the gas retention ages are estimated. No evidence for the presence of products from plutonium-244 or iodine-129 was found. 相似文献
57.
Jaísa Casetta Ricardo Pereira Ribeiro Vanessa Lewandowski Angélica de Souza Khatlab Adhemar Rodrigues de Oliveira Neto Wilson Rogério Boscolo Eliane Gasparino 《Journal of animal physiology and animal nutrition》2021,105(6):1214-1225
This study evaluated the effect of methionine supplementation, predation risk and their interaction on gut histology, whole-body cortisol levels, and intestinal gene expression in zebrafish. A total of 360 one-year-old animals were maintained under two environmental conditions and fed diets containing different methionine sources. Fish were fed either a control diet (CTL, without methionine supplementation), a diet supplemented with dl -methionine (DLM), or a diet supplemented with methionine dipeptide (MM) in the absence (AP) of a predator or in the presence of the predator (PP) for 48 h or 20 days. Predator-induced stress for 20 days resulted in lower body weight. Zebrafish fed methionine-supplemented diets had higher weight gain than control fish. We found no effect of predation stress or methionine supplementation on cortisol level. Predation risk and methionine supplementation showed no interaction effect on dipeptide transporter gene expression. After 48 h of predation pressure, zebrafish had higher mRNA expression of SOD2, CAT and GPX1 in the gut. After 20 days of exposure to the predator, zebrafish fed methionine-supplemented diets had lower expression of GPX1, SOD2 and CAT than those diet CTL. Methionine dipeptide and free methionine supplementation improved growth, intestinal health and survivability of zebrafish both conditions. 相似文献
58.
J.P. Martin K. Haidfr W.J. Farmkr Eliane Fustec-Mathon 《Soil biology & biochemistry》1974,6(4):221-230
Studies were made to determine the rate of decomposition of some 14C-labeled microbial polysaccharides, microbial cells, glucose, cellulose and wheat straw in soil, the distribution of the residual 14C in various humic fractions and the influence of the microbial products on the decomposition of plant residues in soil. During 16 weeks from 32 to 86 per cent of the C of added bacterial polysaccharides had evolved as 14CO2. Chromobacterium violaceum polysaccharide was most resistant and Leuconostoc dextranicus polysaccharide least resistant. In general the polysaccharides, microbial cells, and glucose exerted little effect on the decomposition of the plant products. Upon incubation the 14C-activity was quickly distributed in the humic. fulvic and extracted soil fractions. The pattern of distribution depended upon the amendment and the degree of decomposition. The distribution was most uniform in the highly decomposed amendments. After 16 weeks the bulk of the residual activity from Azotobacter indicus polysaccharide remained in the NaOH extracted soil. From C. violaceum polysaccharide both the extracted soil and the humic acid fraction contained high activity. About 50–80 per cent of the residual activity from the 14C-glucose, cellulose and wheat straw amended soils could be removed by hydrolysis with 6 n HCl. The greater part of this activity in the humic acid fraction was associated with the amino acids and that from the fulvic acids and residual soils after NaOH extraction with the carbohydrates. About 8 16 per cent of the activity of the humic acid fraction was present in substances (probably aromatic) extracted by ether after reductive or oxidative degradation. 相似文献
59.
Luis?J.?álvarezEmail author Adrián?A.?Fernández-Bremauntz Eliane?R.?Rodrigues Guadalupe?Tzintzun 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(3):276-290
Exposure to high levels of pollution is a persistent problem in large cities throughout the world. The ability to predict
the occurrence of a high level of a pollutant allows environmental authorities to take preventive measures, such as controlling
the emission of pollution. Communities and officials can also take actions to reduce the exposure of susceptible groups in
the population. Therefore, being able to estimate the behavior of a given pollutant is of great importance. In this article
we use a Markov chain model to study this behavior. In order to do so, we consider the sequence of the daily maximum measurements
of a pollutant and let successive intervals containing them follow a Markov chain of order K>-0. The novelty here is that we allow K to be a random variable and estimate it and the corresponding transition probabilities using a maximum a posteriori method. The results are used to perform estimations about the behavior of ozone levels in Mexico City. 相似文献
60.
Christen D Tharin M Perrin-Cherioux S Abou-Mansour E Tabacchi R Défago G 《Journal of agricultural and food chemistry》2005,53(18):7043-7051
Eutypine, 4-hydroxybenzaldehyde, and 3-phenyllactic acid are some of the phytotoxins produced by the pathogens causing Eutypa dieback and esca disease, two trunk diseases of grapevine (Vitis vinifera). Known biocontrol agents such as Fusarium lateritium and Trichoderma sp. were screened for their ability to consume these toxins. Transformation time courses were performed, and an high-performance liquid chromatography-based method was developed to analyze toxin metabolism and to identify and quantify the converted products. The results show that the aldehyde function of eutypine was reduced to eutypinol, as by V. vinifera cv. Merlot, the cultivar tolerant to Eutypa dieback. We revealed a supplementary detoxification pathway, not known in Merlot, where the aldehyde function was oxidized to eutypinic acid. Moreover, some strains tested could further metabolize the transformation products. Every strain tested could transform 4-hydroxybenzaldehyde to the corresponding alcohol and acid, and these intermediates disappeared totally at the end of the time courses. When biological assays on cells of V. vinifera cv. Chasselas were carried out, the transformation products exhibited a lower toxicity than the toxins. The possibility of selecting new biocontrol agents against trunk diseases of grapevine based on microbial detoxification is discussed. 相似文献