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991.
Foreign travel     
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992.
1. A caliper technique for estimating the amount of abdominal fat in live broilers is described.

2. Sixty‐three male and 47 female broilers sampled at 63 d of age from an unselected control line were used to examine the accuracy of the caliper measure in predicting abdominal fat.

3. Phenotypic correlations between caliper measure and the proportion of abdominal fat were + 0.80, +0.79 and +0.81 in males, females and the heaviest 20% of males respectively.

4. The application of the technique as an indirect means of selecting for decreased abdominal fat in commercial broiler breeding programmes is discussed.  相似文献   

993.
1. In a series of experiments with laying hens, attempts were made to eliminate the anti‐nutritive factor which reduces egg production when feeding field beans (Vicia faba L.) as a source of supplementary protein in cereal‐based diets.

2. Neither pelleting diets nor heat processing the beans by autoclaving proved beneficial. A continuous‐flow process for infra‐red heating of the seeds at 150 °C for 70 s followed immediately by flaking (micronisation) gave inconsistent results.

3. Beans having a white skin with associated low tannin content, did not support significantly higher egg production than did a normal brown‐skinned bean, thus indicating that tannin was not the main anti‐nutritive factor.

4. A cotyledon fraction, obtained by mechanical removal of the tannin‐containing skin from brown beans, did not support higher egg production than did the whole bean, and the corresponding brown‐skin fraction did not reduce egg production when substituted for cereal in the control diet. Again this indicated that tannin was not implicated.  相似文献   

994.
1. Dry rabbit excreta were found to contain 188.1 g crude protein, 6.6 g non‐protein nitrogen, 0.3 g ammonia, 89.8 g moisture, 8.0 g ether extractives, 135.2 g crude fibre, 266.9 g ash and 19.18 MJ gross energy/kg. Methionine and lysine contents were 3.95 and 4.29 g/100 g protein, respectively.

2. In one experiment, 0, 50, 100 or 200 g rabbit excreta/kg were substituted for maize in a broiler diet. Chickens receiving the diet containing 200 g rabbit excreta/kg gained significantly less weight to 8 weeks of age than those receiving other diets.

3. In a second experiment, 0, 100, 150 or 200 g rabbit excreta/kg were substituted primarily for maize in a broiler diet to provide equal energy and protein contents. Weight gains to 8 weeks of birds receiving these diets did not differ significantly. The uncorrected metabolisable energy content of the excreta was 9.15 MJ/kg.

4. There were no gross pathological changes in the birds fed on the experimental diets.  相似文献   

995.
1. Growth and food conversion efficiency of broilers were reduced at low dietary choline concentrations. These effects were accentuated by low dietary total sulphur amino acids (TSAA).

2. Increased mortality, perosis and other pathological changes involving a number of tissues were observed in birds fed on a low‐choline diet.

3. Methionine replaced part of the dietary requirement for choline at low dietary choline concentrations.

4. High dietary concentrations of choline (> 1 750 mg/kg) increased the requirement for dietary TSAA.

5. Increasing the dietary choline while maintaining the TSAA at an inadequate level may decrease performance.  相似文献   

996.
1. The amount of down‐grading due to bruising in 55 flocks of broilers was investigated.

4. Bruising was classified as light or bad bruising and it is suggested that this division represents two distinct types of bruises with different causes.

3. The incidence of bruising was greater in female flocks than in male although the bruising in the former tended to be less severe.

4. The relationships between incidence of bruising and several variables associated with the flock and the environment were examined using regression analysis. The factors shown to have a significant influence on the incidence of bruising were: the age and mean weight of the flock, and the temperature and humidity on the day of processing.  相似文献   

997.
998.
D. V. CLAY 《Weed Research》1980,20(2):97-102
The tolerance of strawberries to herbicides was tested by applications to the roots of plants growing in sand and by foliage applications to plants grown in compost, and compared with tolerance in the field. Dimefuron was safe as a foliar application but much more toxic than simazine when applied in sand or in the field. Metamitron caused slight injury as a foliar spray; in sand and in the field it was intermediate in toxicity between simazine and lenacil. At normal rates propachlor was safe as a foliar spray and much safer than lenacil when applied in sand. High rates had no adverse effect in the field. Ethofumesate and pendimethalin caused some temporary stunting when applied to foliage, but were less toxic than lenacil when applied to roots in sand. Field applications of both herbicides at 1–1.5 kg/ha were safe. Foliage sprays of bentazone, oxadiazon and oxyfluorfen severely damaged the sprayed leaves, but these herbicides were less active than lenacil when applied to the roots. In the field they caused severe leaf damage, but by the end of the growing season the plants had recovered. The experiments demonstrated the value of separate root and shoot activity tests for indicating which herbicides merit further field testing.  相似文献   
999.
Studies were conducted in the green house on 14C-methyllabelled glyphosate translocation in johnsongrass as affected by rhizome length and growth stage. The amount of 14C measured by the liquid scintillation technique in the rhizomes (2-8%) increased with rhizome length (10, 20 or 30 cm) and tended to increase with growth stage (15-30 cm tall, 45-60 cm tall, or at seedhead), but the amount of 14C per g fresh rhizome weight was almost similar in all cases. Of the total amount applied per plant (0·2 μCi) about 1/3 or less remained on the treated leaf area, while another 1/3 was a absorbed into the treated leaves. Autoradiographs showed that the 14C label moved to all plant parts, basipetally and acropetally. Migration du glyphosate 14 C chez le sorgho d'Alep (Sorghum halepense L. Pers.) en relation avec le stage de croissance et la longueur du rhizome Des recherches ont été effectuées en serru sur la migration du glyphosate marqué au 14C sur le méthyle, chez le sorgho d'Alep, en relation avec la longueur du rhizome et le stade de croissance. La quantité de 14C mesurée par la technique de scintillation liquide dans les rhizomes (2 à 8%) s'est accrue avec la longueur du rhizome (10, 20 ou 30 cm) et elle a eu tendance à augmenter avec le stade de croissance (Hauteur 15-30 cm, hauteur 45-60 cm ou épiaison), mais la quantité de 14C par gramme de poids frais de rhizome est restée Presque identique dans tous les cas. Environ 1/3, ou moins, de la quantitéà la surface des feuilles traitées par plante (0,2 μCi), est restéà la surface des feuilles traitées cependant qu'un autre 1/3 a été absorbé dans less feuilles traitées Les autoradiographies ont montré que le 14C marqueur a migré dans toutes les parties de la plante, dans le sens basipète et dans le sens acropète. Translokation von 14C-Glyphosat in Johnsongras (Sorghum halepense L. Pers.) in Abhängigkeit vom Wachstumsstadium der Pflanzen und der Rhizomlänge Im Gewächshaus wurden Versuche über die Translokation von 14C-Glyphosat in Johnsongras (Sorghum halepense L. Pers.) in Abhängigkeit vom Wachstumsstadium der Pflanzen und der Rhizomlänge durchgeführt. An den Rhizomen stieg der Gehalt von 14C(2–8%), gemessen mit der Flüssig-Szintillationstechnik, mit zunehmender Rhizomlänge (10, 20 oder 30 cm) an und nahm tendenziell auch mit fortschreitendem Pflanzenwachstum zu (15–30 cm und 45–60 cm Sprosslänge oder nach dem Rispenschieben); jedoch blieb die Menge pro g Rhizomfrischgewicht beinahe konstant. Von der insgesamt ausgebrachten Menge pro Pflanze (0.2 μCi) blieben bis zu 1/3 auf der behandelten Blättern absorbiert wurde. Die Autoradiographie zeigte, dass der 14C markierte Teil in alle Pflanzenteile sowohl basipetal wie auch akropetal transportiert wurde.  相似文献   
1000.
Absorption and translocation of 14C fosamine (ethyl hydrogen (aminocarbonyl) phosphonate) and/or fosamine metabolites were monitored in intermediately susceptible seedling black cherry (Prunus serotina Ehrh.) and resistant seedling rhododendron (Rhododendron sp.) and magnolia (Magnolia sp.). The mid two-thirds of the third leaf below the apical bud of each plant was treated with 0·5 μCi 14C fosamine (carbonyl carbon labelled). Plants were harvested 3, 7 and 14 days following treatment. In black cherry the majority of 14C absorption and translocation occurred during the second week following treatment, while magnolia and rhododendron translocated and absorbed most of the 14C within 3 days after treatment. Retention of 14C in the treated portion of the treated leaf did not differ between species. However, total translocated 14C was greatest in black cherry, less in magnolia, und minimal in rhododendron. Magnolia translocated 14C basipetally, while black cherry translocated acropetally, as well as basipetally. Absorpiion et migration de la fosamine 14C chez trois espèces de plantes ligneuses L'absorptlon et la migration de La 14C fosamine ((amino carbonyl) phosphonate d'éthyle hydrogène) et/ou de ses métabolites, ont étéétudiées chez des plantules moyennement sensibles de Prunus serotina (Ehrh.) et chez des plantules résistantes de rhododendron (Rhododendron sp.) et de magnolia (Magnolia sp). Les deux tiers moyens de la troisième feuille en-dessous du bourgeon apical de chaque plant ont été traités avec 0.5 Ci 14C de fosamine (marquée sur le carbone du carbonyl). Les plantes ont été récoltées 3, 7 et 14 jours après le traitement. Chez P. serotina, la plus grande partie de l'absorption et de la migration du 14C a eu lieu durant la deuxième semaine après le traitement, alors que chez le magnolia et le rhododendron, le maximum d'adsorption et de migration s'est situé dans les trois jours qui ont suivi le traitement. La rétention du 14C dans la partie traitée n'a pas variè d'une espèce à l'autre. Toutefois, la quantité totale de 14C qui a migré a été plus grande chez P. serotina, moindre chez le magnolia et minimaie chez le rhododendron. Chez le magnolia, la migration du 14C s'opere dans le sens basipète, alors que chez le P. serotina. elle s'effectue aussi bien dans le sens acropète que dans le sens basipète. Aufnahme- und Trunstokaiion von 14C-Fosaminc bei drei Gehölzpflanzen Es wurde die Aufnahme und die Translokation von 14C Fosamine (O-Äthyl-aminocarbonylphosphonsäure) und/oder seiner Abbauprodukte bei drei Gehölzarten beobachtet. Verwendet wurden Sämlinge der Traubenkirsche (Prunus serotina Ehrh.), die eine mittlere Empfindlichkeit zeigt und Sämlinge des resistenten Rhododendron (Rhododendron sp.) und der ebenfalls resistenten Magnolie (Magnolia sp.). Die mittleren zwei Drittel des dritten Blattes unterhalb der Endknospe wurden bei jeder Pflanze mit 0.5 μCi 14C-Fosamine (markiert am Carbonylkohlenstoff) behandelt. Die Pflanzen wurden nach 3, 7 und 14 Tagen nach der Behandlung geerntet. Bei der Traubenkirsche wurde während der zweiten Woche am meisten 14C aufgenommen und transloziert, während dies bei der Magnolie und dem Rhododendron bereits innerhalb der ersten drei Tage der Fall war. Bezüglich der Retention von 14C in der behandelten Blattfläche unterschieden sich die drei Arten nicht. In der Traubenkirsche wurde aber am meisten 14C transloziert, weniger in der Magnolie und am wenigsten im Rhododendron. Die Magnolie translozierte das 14C basipetal, während die Traubenkirsche akropetal wie basipetal translozierte.  相似文献   
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