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71.
The effect of homogenized embryos on IUD-induced luteal regression in the ewe was studied. Plastic spiral IUDs were inserted in an uterine horn adjacent to an ovary containing a corpus luteum during various times of the estrous cycle. The ewes were sacrificed on Day 6 for examination of the corpus luteum. Estrous Cycle Day 3 was the last day in which the IUD insertion induced luteal regression. Corpus luteum was maintained in ewes when the IUD was inserted on Day 4, 5, or 6. Corpus luteum regression was not prevented when homogenized 14- or 15-day-old embryos were injected into the uterus at the time of IUD insertion. Ewes which received an IUD, a cannula, and an infusion of saline or homogenized embryos on Days 3, 4, and 5 maintained corpora lutea in 4 of 7 embryo-infused ewes and in none of 7 saline-infused ewes (p less than .05). It was determined that the IUD must remain in the uterine horn for longer than 1 day to induce corpus luteum regression and that embryos can sometimes prevent the IUD-induced regression. 相似文献
72.
K. Verhoeff Judith M. Warren 《European journal of plant pathology / European Foundation for Plant Pathology》1972,78(4):179-185
The production and activity of pectolytic and cellulolytic enzymes byBotrytis cinerea in tomato plants, as well as by conidia of this fungus in some nutrient media was studied. In inoculated tomato plants, the activity of these enzymes varied. PME, endo-PG and exo-PG were produced in petioles and fruits, while cellulase was only found in those parts which were softened by the invading mycelium. PGTE could only be detected in the softened parts of the petiole stumps. In suitble substrates, PME, endo-PG and exo-PG are produced rapidly with the onset of germination of the conidia. At some temperatures, endo-PG activity was found before germination could be observed. Some endo- and exo-PG was detected in washing water of conidia. The significance of the production of these enzymes by germinating conidia in relation to the infection process on tomato plants is discussed.Samenvatting In geïnoculeerde delen van een tomateplant blijkt de activiteit van deze enzymen afhankelijk te zijn van de aard van het aangetaste weefsel en de mate van aantasting (Tabel 1). Conidiën blijken in bepaalde media zeer snel pectolytische enzymen te vormen (Tabel 2, Fig. 1). Endo-PG activiteit kon bij 26° en 30°C in een natriumpolypectaatmedium worden gemeten voordat kieming van de conidiën kon worden aangetoond, zij het in zeer geringe hoeveelheid, lijkt aanwezigheid van deze twee enzymen in niet gekiemde conidiën aannemelijk. PME blijkt in een pectinebevattend medium te kunnen worden aangetoond op het moment, waarop kiembuizen zichtbaar worden. Cellulase kon daarentegen in een medium met kiemende sporen niet worden gevonden. 相似文献
73.
EFFECT OF DISRUPTION OF THE SEBACEOUS LAYER OF THE SHEEP''S SKIN ON THE INCIDENCE OF FLEECE-ROT 总被引:1,自引:0,他引:1
It was postulated that integrity of the sebaceous layer on the skin is important in maintaining resistance to fleece-rot. This hypothesis was tested in an experimenta of a 2 x 2 factorial design in which sebaceous layer disruption and wetting were the 2 treatments. The sebaceous layer was disrupted by applying a light petroleum solvent to the skin of the sheep. Fleece-rot occurred in all sheep (20) that were both wetted and had the sebaceous layer disrupted while 9/19 of those wetted but without the sebaceous layer disrupted developed fleece-rot. The fleece-rot lesions observed were more severe in sheep in the disrupted wetted treatments than in the intact wetted treatment. Interpretation of these differences was complicated by a possible reaction of the skin to the solvent used. The differences were not due to an effect of treatment on fleece wettability. No fleece-rot developed in the sheep not wetted and application of the solvent alone did not induce fleece-rot. 相似文献
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JE BAUER 《Australian veterinary journal》1994,71(10):342-345
SUMMARY The metabolism and clinical potential for dietary polyunsaturated fatty acids (PUFAs) modifications using oil supplements containing n-3 and n-6 fatty acids are reviewed. Their use in such disorders as renal disease, inflammatory and immune-related disorders, and dermatological conditions in dogs and cats is discussed. The influence of n-3 fatty acid-rich rations on the endotoxin response in horses is described. Progress has been made toward understanding the clinical potential for PUFAs in these species. However, they have not yet been shown to be efficacious in any of the conditions investigated. 相似文献
80.
Perkins-Veazie P Collins JK Davis AR Roberts W 《Journal of agricultural and food chemistry》2006,54(7):2593-2597
The lycopene content of 50 commercial cultivars of seeded and seedless red-fleshed watermelons was determined. Scanning colorimetric and spectrophotometric assays of total lycopene were used to separate watermelon cultivars into low (<50 mg/kg fw), average (50-70 mg/kg fw), high (70-90 mg/kg fw), and very high (>90 mg/kg fw). Cultivars varied greatly in lycopene content, ranging from 33 to 100 mg/kg. Most of the seeded hybrid cultivars had average lycopene contents. Sixteen of the 33 seedless types had lycopene contents in the high and very high ranges. All-trans-lycopene was the predominant carotenoid (84-97%) in all watermelon cultivars measured by high-performance liquid chromatography, but the germplasm differed in the relative amounts of cis-lycopene, beta-carotene, and phytofluene. Red-fleshed watermelon genotypes vary extensively in carotenoid content and offer opportunities for developing watermelons with specifically enhanced carotenoids. 相似文献