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1.
The crossreactivity of mouse monoclonal antibodies (MoAbs) (Tab. I) prepared against human HLA-DR and HLA-DP antigens was studied in various bovine cells: lymphocytes from lymph nodes and peripheral blood, adherent (B) and nonadherent (T) lymphocytes, monocytes, granulocytes and platelets. In the immunofluorescence test, MoAbs Bra13, Bra14, Bra20, Bra22, Bra30, Bra70, HL-38 reacted with bovine B lymphocytes and monocytes, but not with other tested cells (Tab. III, IV). These antibodies, except Bra22, were positive with B lymphocytes in the complement dependent cytotoxic test (Tab. II). The similarity of the bovine antigens and HLA-DR antigens determined by used MoAbs was also proved by immunoblotting. Monoclonal antibodies Bra38 and BraFB6 did not react with the bovine cells and separated antigens. The epitope (HLA-DR) recognized by the antibody Bra38 is probably absent in cattle. The presence of HLA-DP analogue determined by the antibody BraFB6 has not been confirmed. The crossreactive MoAbs could be used for the detection of B lymphocytes and macrophages in veterinary immunology.  相似文献   
2.
A central axonopathy in 2 male and 1 female Scottish Terrier puppies from 3 different but related litters is reported. Clinical signs consisting of severe whole-body tremors and ataxia were first detected at the age of 10 to 12 weeks. They worsened with activity and excitement and diminished during rest or sleep. Two dogs also had paraparesis. In 1 dog the neurological deficits progressed over several months. Neuropathological examination revealed widespread axonal changes, vacuolation, and gliosis in the white matter of the central nervous system.  相似文献   
3.
The present study examined the distribution of particle sizes in two experimental standardized lipid emulsions (distributed by ICES, International Council for the Exploration of the Sea) as a function of the preparation method (hand shaking or ultrasonic blending) and as a function of storage time. A 24-h enrichment trial compared the incorporated HUFA levels in the nauplii of Artemia franciscana .
The emulsion droplets in the 50% HUFA emulsion (ICES 50, ethyl ester based) were much smaller than in the 30% HUFA emulsion (ICES 30, triacylglycerol-based) in which 90% of the droplets had a diameter below 12.3 μm as compared to 1.3 pn in ICES 50. The blending method highly affected particle sizes. High-shear blending instead of the classical hand shaking of the emulsion of both ICES 30 and 50 reduced the mean particle size from 5.06 to 1.07 μm and from 0.38 to 0.11 μm, respectively. The particle size distributions remained stable during the 1-wk storage, suggesting the absence of agglomeration or bacterial development. The fatty acid composition of 24-h enriched Artemia reflected differences in the HUFA profile of the emulsions, but was independent of observed differences in the size of the particles.  相似文献   
4.
Soon after its introduction the mushroom speciesAgaricus bitorquis, which is immune to virus disease and prefers a warm climate, was threatened by the competitorDiehliomyces microsporus, false truffle. This fungus also likes warmth, and used to occur in crops ofA. bisporus.Mycelium and ascocarps were grown on several nutrient media. Optimum temperatures for mycelial growth were 26°C and 32°C, with a slight depression at 30°C. In trials in isolated growingrooms strain Somycel 2.017 ofA. bitorquis was generally used since it appeared to be highly sensitive to the competition of false truffle. Inoculation with mycelium, ascocarps or ascospores ofD. microsporus nearly always resulted in the presence of the competitor and in decreased mushroom yields. Even ten spores per m2 causedD. microsporus. The time of inoculation was most important: irrespective of the kind of inoculum, inoculation only resulted in both false truffle and yeild loss, if applied from spawning until a few days after casing. Inoculation at a later date could result in false truffle, but yield was not decreased.As germination in vitro of ascospores failed, even after addition of various triggers, ascospore suspensions were treated at various temperatures for several periods. Then mushroom growing trays spawned with Somycel 2.017 were inoculated with the treated suspensions giving 7–11×107 spores/m2. The ascospores could not withstand 85°C for 0.5 h, 80°C for 1 h and 70°C for 3 h. Spontaneous incidence of false truffle, however, could not always be prevented and interfered with the results of these trials. It is possible that the thermal death-point of the ascospores is below 85°C. Fruiting bodies and ascospores did not survive peak-heating at the beginning and cooking out (compost temperature 12 h at 70°C) at the end of a crop. After cooking out, however,D. microsporus could still be present in the wood of trays and contaminate a following crop if no wood preservative was applied.Yield of Somycel 2.017 was reduced by the competition ofD. microsporus much more than yeilds of other strains ofA. bitorquis. The least sensitive were the highly productive strains Horst K26 and Horst K32.The effects of fungicides onD. microsporus in vitro and in growing trials did not correspond. The fungicides tested so far could not prevent or controlD. microsporus. Growing of less sensitive strains ofA. bitorquis together with sanitary measures early in the crop and at the end of the crop, however, can prevent the competitor. failure to turn up of false truffle. To understand the discrepancy between the in vitro effects of several fungicides and their effect in inoculated mushroom trays, the rate of adsorption of benomyl in the substrate and probably the interrelationships between antagonists andD. microsporus require further research. Other strains ofA. bitorquis than Somycel 2.017 appeared to be less sensitive to the competition. Among these, highly productive strains Horst K26 and Horst K32 will not be hindered byD. microsporus if the following precautions are exercised: cooking out at the end of a crop (compost temperature 70°C for 12 hours), followed by treatment of the wood with SPCP; protection by hygiene early in the crop, i.e. covering of the compost by a thin plastic sheet during mycelial growth followed by a quick execution of casing.Samenvatting De teelt van de warmteminnende champignonsoortAgaricus bitorquis, die immuun is voor virusziekte, werd al spoedig na introductie bedreigd door de eveneens warmteminnende concurrentDiehliomyces microsporus, valse truffel. Deze schimmel kwam vroeger voor in teelten vanA. bisporus; de sporen zouden een temperatuur van 82°C gedurende 5 uur kunnen overleven (Lambert, 1932). Tabel 1 geeft de myceliumgroei op verschillende voedingsbodems en de vorming van vruchtlichamen (Fig. 1A, B) weer. De optimale temperaturen voor myceliumgroei waren 26°C en 32°C, met een licht depressie bij 30°C (Fig. 2). Proeven in geïsoleerde teeltruimten werden voornamelijk uitgevoerd met Somycel 2.017, een ras vanA. bitorquis. Inoculatie met mycelium, vruchtlichamen en/of ascosporen vanD. microsporus, al of niet in reincultuur gekweekt, leidde vrijwel steeds tot de aanwezigheid van de concurrent in de geïnoculeerde teeltkisten (Fig. 1C, D), waarbij vruchtlichamen met ascosporen (Fig. 1E) gevormd werden en tot een reductie van het aantal champignons. Tien sporen per m2 waren al voldoende omD. microsporus te doen aanslaan (Fig. 3). Het tijdstip van inoculatie bleek van groot belang te zijn: onafhankelijk van de aard van het inoculum leverde dit slechts zowel valse truffel als oogstreductie op, indien het werd aangebracht in de periode vanaf enten tot enkele dagen na het afdekken (Tabel 2 en Fig. 4). Inoculatie op latere tijdstippen kon wel tot valse truffel leiden, maar niet tot oogstreductie.Aangezien de kieming van ascosporen in vitro slechte resultaten opleverede, ook na toevoeging van diverse stimulantia, werden ascosporensuspensies in vitro gedurende verschillende tijden bij verschillende temperaturen behandeld; vervolgens werden teeltkisten met de behandelde suspensies geïnoculeerd (7 tot 11×107 sporen/m2). De kisten waren tevoren geënt met Somycel 2.017. Een aantal proeven wees uit, dat de ascosporen 1/2 uur 85°C, 1 uur 80°C en 3 uur 70°C, niet overleefden (Tabel 3). Het spontaan optreden van valse truffel kon echter niet altijd worden voorkomen en beïnvloedde de uitkomsten van deze proeven. Daarom is het mogelijk, dat de sporen al bij een lagere temperatuur worden gedood Vruchtlichamen en ascosporen werden gedood door het uitzweten aan het begin van een teelt en door het doodstomen aan het einde van een teelt (composttemperatuur 12 uur 70°C) maar de schimmel bleek in het laatste geval wel over te kunnen blijven in het hout van teeltkisten als er vervolgens geen houtontsmettingsmiddel werd toegepast.Somycel 2.017 leed verhoudingsgewijs meer schade door concurrentie vanD. microsporus dan enkele andere rassen (Tabel 4 en. 5). Inoculatie met ascosporen bleek bij de minst gevoelige en meest produktieve rassen Horst K26 en Horst K32 slechts te gelukken in extreem droge compost; bij Somycel 2.017 daarentegen zowel in compost met een laag als met een hoog vochtgehalte. Inoculatie met mycelium veroorzaakte meer valse truffel en meer schade naarmate de compost natter was (Tabel 5).De werking van een aantal fungiciden in vitro (Tabel 6) en in teeltkisten (Tabel 7) stemde niet overeen. Aangezien de tot nu toe getoetste fungicidenD. microsporus niet kunnen voorkomen of bestrijden, moet preventie van deze concurrent worden gezocht in het telen van weinig gevoelige rassen vanA. bitorquis in combinatie met hygiënische maatregelen vroeg in en aan het eind van de teelt.  相似文献   
5.
Hydraulic conductivity between saturation and a tension of 100 cm water was calculated with moisture-retention data for nine soil horizons and compared with results from in situ measurements with the crust test. Agreement was good for sandy, apedal soil horizons with simple packing voids but only if matching factors were used. Results were unreliable in clayey, pedal soil horizons in which a few relatively large planar and tubular pores determine K in the measured tension range, whereas the greatest fraction of total porosity is composed of fine pores inside peds that hardly contribute to flow. Varying the number of pore classes (n) and the water-filled porosity at saturation made no significant difference in the calculations for the apedal soils, but drastically changed the shape of the calculated curves for the pedal soils. Matching factors based on Ksat measurement had to be used for all studied soil horizons, indicating that Marshall's pore-interaction model never predicted Ksat accurately.  相似文献   
6.
7.
Summary Tubers (still unsprouted after an eight months' storage period) of the late varietyLibertas with slow growth in youth and few stems were treated with gibberellic acid (GA3) in 1958 and 1959. Two sprayings gave similar results as dipping for 15 minutes. 25 ppm probably had more effect than 12,5 ppm. During both years the treatment resulted in more and longer sprouts and more stems, although the number of stems is usually less than the number of sprouts. Emergence was not accelerated and in both years yields tended to be lower. In 1958 all yields reached a high level, treatment gave a non-significant lower yield, but there was a greater number of tubers especially in the 25–40 mm seed-class. In 1959 the size and the number of tubers were affected by second growth owing to the unusually dry summer with short spells of rainy weather. In this year presprouted tubers emerged 10 days earlier than treated and non treated, unsprouted seed, which for a long period gave the crop a lead in haulm growth and even a permanent lead in tuber yield.
Zusammenfassung Von der sp?ten SorteLibertas, die in ihrer Jugend ein langsames Wachstum zeigt und wenig Stengel entwickelt, wurden ungekeimte Knollen (nach 8-monatiger Lagerung) in den Jahren 1958 und 1959 mit Gibberellins?ure (GA3) behandelt. Eine zweimalige Spritzung ergab zumindest ?hnliche Ergebnisse wie das Eintauchen w?hrend 15 Minuten. 25 ppm hat wahrscheinlich eine bessere Wirkung, wie 12,5 ppm. In beiden Jahren ergab die Behandlung mehr und l?ngere Keime sowie mehr Stengel, obzwar die Anzahl der Stengel gew?hnlich nicht so hoch ist, wie die Anzahl der Keime. Es zeigte sich keine Beschleunigung des Auflaufens, jedoch eine Tendenz für einen geringeren Ertrag in beiden Jahren. In 1958 waren alle Ertr?ge hoch und die Behandlung ergab eine nicht signifikante Ertragsverminderung, jedoch eine gr?ssere Knollenzahl (insbesondere in der Saat-Gr?ssenklasse, 25–40 mm). In 1959 war die Gr?sse und die Anzahl der Knollen infolge des ungew?hnlich trockenen Sommers mit kurzen Regenperioden durch Mehrwüchsigkeit beeintr?chtigt. In diesem Jahr sind die vorgekeimten Knollen um 10 Tage früher aufgelaufen, was den Pflanzen im Vergleich zu den behandelten und nicht behandelten ungekeimten Pflanzgut einen l?ngeren Vorsprung im Krautwuchs und einen dauerhaften Vorsprung in der Knollenbildung gab.

Résumé Des tubercules non germés (après stockage pendant huit mois) de la variété tardiveLibertas, à lente croissance de début et à petit nombre de tiges, ont été traités à l'acide gibberellique (GA3) en 1958 et en 1959. Deux pulvérisations donnaient des résultats au moins égaux à ceux d'une immersion de 15 minutes. La concentration de 25 millionièmes est probablement plus efficace que celle de 12,5 millionièmes. L'une et l'autre année, les tubercules traités avaient des germes plus nombreux et plus longs et un plus grand nombre de tiges, bien que le nombre de tiges ne soit généralement pas aussi grand que le nombre de germes. La levée ne fut pas accélérée et il se manifesta une tendance de diminution du rendement. En 1958, toutes les récoltes furent bonnes, le traitement entra?nant une diminution non significante de la récolte mais faisant augmenter le nombre de tubercules (particulièrement dans la catégorie de semenceaux de 25–40 mm). En 1959, la grosseur et le nombre des tubercules furent influencés par croissance secondaire (excroissance) par suite de l'été exceptionnellement sec avec de courtes périodes de pluie. Cette année-là, les tubercules prégermés levèrent 10 jours plus t?t que les plants non prégermés, traités et non traités, de sorte que le développement du feuillage fut supérieur pendant une longue période et que celui des tubercules fut supérieur jusqu'à la récolte.
  相似文献   
8.
Fucosylated chondroitin sulfates (FCSs) FCS-BA and FCS-HS, as well as fucan sulfates (FSs) FS-BA-AT and FS-HS-AT were isolated from the sea cucumbers Bohadschia argus and Holothuria (Theelothuria) spinifera, respectively. Purification of the polysaccharides was carried out by anion-exchange chromatography on DEAE-Sephacel column. Structural characterization of polysaccharides was performed in terms of monosaccharide and sulfate content, as well as using a series of non-destructive NMR spectroscopic methods. Both FCSs were shown to contain a chondroitin core [→3)-β-d-GalNAc-(1→4)-β-d-GlcA-(1→]n bearing sulfated fucosyl branches at O-3 of every GlcA residue in the chain. These fucosyl residues were different in pattern of sulfation: FCS-BA contained Fuc2S4S, Fuc3S4S and Fuc4S at a ratio of 1:8:2, while FCS-HS contained these residues at a ratio of 2:2:1. Polysaccharides differed also in content of GalNAc4S6S and GalNAc4S units, the ratios being 14:1 for FCS-BA and 4:1 for FCS-HS. Both FCSs demonstrated significant anticoagulant activity in clotting time assay and potentiated inhibition of thrombin, but not of factor Xa. FS-BA-AT was shown to be a regular linear polymer of 4-linked α-L-fucopyranose 3-sulfate, the structure being confirmed by NMR spectra of desulfated polysaccharide. In spite of considerable sulfate content, FS-BA-AT was practically devoid of anticoagulant activity. FS-HS-AT cannot be purified completely from contamination of some FCS. Its structure was tentatively represented as a mixture of chains identical with FS-BA-AT and other chains built up of randomly sulfated alternating 4- and 3-linked α-L-fucopyranose residues.  相似文献   
9.
Four hundred and forty-three Dutch field isolates of Haemophilus pleuropneumoniae were serotyped by rapid slide agglutination (RSA) using specific antisera against serotypes 1 to 5 and against the recently proposed types 6 to 9. The predominant serotypes were 9 (49%) and 2 (32%). Serotypes 1, 3, 5, 7 and 8 were isolated in small numbers: together they accounted for 3% of the total. Five percent of the isolates were not typable either due to autoagglutination or because they were not agglutinated by any of the available antisera. The remaining 49 strains (11%) agglutinated in more than one antiserum and could therefore not be properly classified. Forty-four of these 49 strains agglutinated in both anti type 1 and anti type 9 serum. Antigenic relationships between serotype 1, serotype 9 and isolates reacting with both antisera were studied using immunodiffusion and RSA with adsorbed sera. Serotype 9 strains appeared not to be a homogenous group. Isolates agglutinating exclusively in anti type 9 serum can be divided into two groups: one closely related and another hardly related to serotype 1. Serotype 9 reference strain 13261 belongs to the latter. Type 1 + 9 strains have antigens in common with serotypes 1 and 9, but they also have their own specific antigenic material. Such strains are proposed as a new serotype 10.  相似文献   
10.
Deal stem disease in asparagus is characterized by yellow dead stems with reddish lesions, mostly at soil level. There are two types of infection. The first one with lesions on the base of the stem at soil level, as a result of which the stem dies off. In the second type of infection the lesions appear higher up on the stems, while stems remain mostly green. The disease was proved to be caused byFusarium culmorum. This fungus is mainly spread through the soil. Air dispersal was demonstrated but seems of little importance to disease incidence.  相似文献   
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