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91.
Missohou A Dieng A Horst P Zarate VA Nesseim T Tchedre K 《Tropical animal health and production》2003,35(4):373-380
The influence of sex-linked dwarf (dw) and incompletely dominant frizzle (F) genes on growth, egg production and quality were investigated. The experimental stock comprised 100 chicks of four genotypes:
normal feathered, normal size (ffDw); normal feathered, dwarf (ffdw); frizzle, normal size (FfDw); and frizzle, dwarf (Ffdw). The dwarf gene reduced the body weight, shank length, feed intake, egg production and egg weight. The frizzle gene also
reduced most of these traits, except for egg production, the interaction between the two genes being positive only for growth
traits and egg number. Neither of the two genes significantly influenced egg quality. It was concluded that the dwarf gene
may have some practical interest in tropical environments, while more needs to be known about the frizzle gene.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
92.
Deutz A Fuchs K Schuller W Nowotny N Auer H Aspöck H Stünzner D Kerbl U Klement C Köfer J 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(7-8):306-311
The aim of this study was to investigate the seroprevalences to zoonotic pathogens in hunters, to propose preventive measures and to obtain more information about the occurrence of zoonotic pathogens in local wild animal populations. From 146 male and 3 female hunters originating from the south-eastern Austrian federal states of Styria and Burgenland blood samples were taken and anamnestic data were obtained using a questionnaire. The serological investigations included the following viral, bacterial and parasitic zoonotic agents or zoonoses, respectively (antibody-seroprevalences in brackets): encephalomyocarditis virus (EMCV, 15%), Puumala-Hantavirus (10%), Newcastle Disease virus (NDV, 4%), borreliosis (IgG 42%, IgM 7%), brucellosis (1%), chlamydiosis (3%), ehrlichiosis (IgG 15%, IgM 3%), leptospirosis (10%), tularaemia (3%), Q fever (0%), Echinococcus multilocularis/E. granulosus (5%/11%), toxocariasis (17%). Out of a control group of 50 persons (urban population, no hunters) only one person was found to be seropositive for Toxocara canis and NDV and four for EMCV, all other results were negative in the control group. The high seroprevalences especially to Borrelia burgdorferi s.l., Ehrlichia spp., Leptospira interrogans, E. granulosus, E. multilocularis, encephalomyocarditis virus and Puumala virus demonstrate that hunters are particularly exposed to zoonotic pathogens. It should also be noted that one hunter was seropositive for Brucella abortus and five exhibited antibodies to Francisella tularensis. In these cases, as well as in the cases of the 15 seropositives for Leptospira interrogans, the suspected source of infection may--besides rodents--also include wild boars and brown hares. The infections with NDV and Chlamydophila psittaci may be traced back to contact with certain species of birds (potential risk: aviaries). For Hantaviruses, rodents are considered to be the main source of human infections. 相似文献
93.
Groenendaal H Nielen M Jalvingh AW Horst SH Galligan DT Hesselink JW 《Preventive veterinary medicine》2002,54(3):225-245
A dynamic and stochastic simulation model (the "JohneSSim model") was developed to evaluate the economic and epidemiological effects of different strategies for control of paratuberculosis in dairy herds. Animals occupy one of the six defined infection states; the spread of Johne's disease is modeled with five infection routes. Many different dairy farm situations can be simulated. Control strategies that can be simulated are: (1) test-and-cull; (2) calf hygiene management; (3) vaccination and (4) grouping of animals. Losses are caused by: (1) reduced milk production; (2) diagnosis and treatment costs; (3) lower slaughter value of cows and (4) sub-optimal culling. The benefits were calculated as reduction in the losses caused by Johne's disease; the costs of each strategy were calculated on the basis of actual costs of each item; and net present value (NPV) was calculated as benefits minus costs. Herd and prevalence data from The Netherlands and Pennsylvania, USA were used. In both situations, a low true mean prevalence within 20 years could be reached only when all calf management tools were applied. The Dutch control program (PPN) was on average economically attractive (with or without labor costs, the average NPV was Euro 1183 and 12,397, respectively). In Pennsylvania, contract heifer rearing and improved calf hygiene reduced the prevalence effectively and had large economic benefits (US$ 43,917 for 20-year period) if the calves were sent to the heifer facility while very young. Validation with data from 21 infected Dutch dairy farms (as well as face-validation: comparison of the results of the JohneSSim model with experiences of Johne's experts) supported the basic assumptions in the model. 相似文献
94.
Summary Since the macroscopical and microscopical examination of bull semen does not in all cases appear to give conclusive indications concerning the fertilizing capacity, an investigation of some biochemical parameters was undertaken. It was shown that the following biochemical examination could furnish some more information about the quality of the semen: 1. Determination of the phenylalanine- α-ketoglutarate transaminase activity both in the seminal plasma and in the whole semen. A high transaminase activity in the plasma points to leakage out of the spermatozoa, thus indicating an affection of the spermatozoa. In that case larger amounts of basic amino acids and of leucine were often found in the seminal plasma than would normally be observed. 2. Gas chromatographic examination of the steroids occurring both in the seminal plasma and in the spermatozoa. In a number of infertile bulls small peaks of progesterone were found together with those of other, unidentified compounds. 3. Investigation of the carbohydrate metabolism in the semen. In a number of fertile bulls the following deviations were found: a. the presence of quite a lot of fructose in the spermatozoa; b. the presence of glucuronic acid and / of other foreign compounds in the spermatozoa or in the plasma; c. an elevated pH in the seminal plasma some 2 to 3 hours after ejaculation; d. a low phenylalanine-α -ketoglutarate transaminase activity in the whole semen (the spermatozoa had been disrupted by freezing). 4. Investigation of the presence of reducing aldehydes (glycolaldehyde and glyceraldehyde) inside the spermatozoa. The determinations mentioned under 1, 3c and 3d can easily be carried out in the laboratories of each District Animal Health Service and of the A.I. stations; the same is true of the occurrence of amino acids in the seminal plasma and of fructose and aldehydes inside the spermatozoa if facilities are available for electrophoresis and chromatography. 相似文献
95.
Hermosilla C Schröpfer E Stowasser M Eckstein-Ludwig U Behrendt JH Zahner H 《Veterinary research communications》2008,32(7):521-531
The first merogony of Eimeria bovis takes place in lymphatic endothelial cells of the ileum, resulting in the formation of macromeronts up to 250 mum. In this study, we investigated the host cell cytoskeleton (actin filaments, microtubules, spectrin, vimentin intermediate filaments) associated with parasitic development in vitro by confocal laser scanning microscopy (CLSM) using primary bovine umbilical vein endothelial cells (BUVEC) and bovine spleen lymphatic endothelial cells (BSLEC) as host cells. No prominent changes in the host cell cytoskeleton were detected 1-3 days after E. bovis sporozoite invasion. With ongoing meront maturation a significant increase in microtubules and actin filaments close to the parasitophorous vacuole (PV) was found. Mature macromeronts within the PV were completely enclosed by these cytoskeletal elements. Our findings suggest, that in order to guarantee the survival of the host cell on the enlargement of macromeronts, E. bovis needs not only to augment but also to rearrange its cytoskeletal system. 相似文献
96.
Turkey poults were fed a vitamin D-deficient diet and examined for clinical signs and structural changes of bone and parathyroid glands. Vitamin D-deficient poults developed ricketic changes during days 10 to 14. Control poults (deficient diet plus vitamin D) did not develop rickets. In deficient poults, lengths of proliferating-prehypertrophied zones of growth plates increased significantly in the proximal tibiotarsus but were only slightly elongated in the distal tibiotarsus. Unmineralized hypertrophic chondrocyte zones increased in length rapidly in conjunction with a decrease in the length of mineralized hypertrophic degenerative zones; this occurred more rapidly in proximal than in distal tibiotarsus. Other ricketic changes included decreases in bone ash, total femoral bone ash (calcium, phosphorus, magnesium), bone length, and body weight. Plasma alkaline phosphatase was increased, calcium was normal, and phosphorus was normal or elevated. Parathyroids were hyperplastic and had foci of degeneration. Vitamin D3 metabolites 25OHD3, 1,25(OH)2D3, and 24,25(OH)2D3 were rapidly depleted. Increase in bone ash Ca/P ratios in deficient poults suggests that phosphorus may be selectively released from ricketic bone. Low 25OHD3 and 1,25(OH)2D3 of control poults early in the experiment suggests that 1,400 IU of vitamin D3/kg of feed may not be an adequate level of vitamin D3 for growing turkey poults. 相似文献
97.
South African juvenile dusky kob Argyrosomus japonicus are more abundant in turbid estuaries than in clear marine‐dominated estuaries. Turbidity can reduce light penetration into the water and create an environment different from that experienced by fish under culture conditions in mechanically filtered clear water. In order to optimize rearing conditions of this species, the effects of light intensity (23–315 lx) and feeding method (restricted ration vs. feeding to apparent satiation) on growth and food conversion ratio (FCR) of juvenile A. japonicus were assessed in a 56‐day growth trial. Fish weight increased from 7.2±1.6 to 41.9±10.2 g fish?1 at a growth rate of 3.25% body weight day?1. Light intensity did not significantly affect growth or FCR. Feeding method did not significantly affect growth rate, but average FCR was significantly better in treatments fed a ration of 3.6% body weight day?1 than in treatments fed to apparent satiation. Therefore, a light intensity range of 23–315 lx can be used to culture dusky kob juveniles. The better FCR in fish fed a restricted ration suggests that a ration of 3.6% body mass day?1 allowed good growth of juvenile dusky kob. 相似文献
98.
99.
To assess the possibilities of the liberation of toxic aromatic amines under different conditions of disposal, the degradation of different14C-labelled polyurethane foams was investigated in the leachate of a refuse tip, in composted municipal waste and in an agricultural soil. With unlabelled foam cubes experiments were run under the environmental conditions of a refuse tip. The degradation of14C-labelled polyureas was studied in different agricultural soils. In the laboratory tests the criteria of degradation were the liberation of aromatic amines and the production of14CO2. The degradation in the refuse tip was estimated on the basis of weight loss. From the results it can be assumed that the polyether based polyurethane foams are largely resistant to microbial as well as chemical attack under all practical conditions of disposal. Polyester based polyurethane foams are susceptible to chemical hydrolysis favored by extreme environmental conditions such as high temperature and/or low or high pH values. Under these circumstances an accumulation of aromatic amines can occur if their further microbial degradation is impeded by the lack of suitable conditions for the growth of microorganisms. No indication of any degradation of the isocyanate based polyureas was found. 相似文献
100.
Wolfgang Gosda Ulrich Wallwitz Horst Schmidt 《Genetic Resources and Crop Evolution》1965,13(1):177-237
Zusammenfassung In dieser zweiten Übersicht sind weitere Literaturergänzungen zum Problem der Struktur und Funktion des genetischen Materials zusammengestellt. Neben gesicherten Fakten wurden auch Hypothesen und unterschiedliche Interpretationen von Untersuchungsergebnissen diskutiert. Die Literatur ist bis November 1964 berücksichtigt.
Summary In this second review further literature on the problem of structure and function of genetic material are summarized. Beside certain experimental results also hypotheses and different interpretations of results are discussed. The survey of the literature for this review was completed in November 1964.
am ¶rt;au , , . . 1964 .相似文献