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431.
Electrocution of Cape vultures Gyps coprotheres in South Africa is reviewed. Data from the ranching areas of the western Transvaal is presented, with details of more than 300 birds known to have been electrocuted between 1970 and 1977. Most birds were electrocuted on 88 kV suspension towers. Surveys with a light aircraft revealed that towers carrying voltages of 132, 275 and 400 kV provided safe perches for vultures, and were regularly used by numbers of birds for roosting in the flat treeless survey area. 相似文献
432.
433.
M J Corke 《The Veterinary record》1988,122(13):305-307
The equipment and materials necessary to prepare and safely administer fluids intravenously to cattle are described. The preparation and clinical uses of Hartmann's solution are discussed, together with modifications of the solution to permit its application to different disease states. 相似文献
434.
Ira M. Gourley D.V.M. Ph.D. Harold R. Parker D.V.M. Ph.D. David H. Gribble D.V.M. Ph.D. G. M. Conzelman Jr. Ph.D. G. Ishizaki D.V.M. 《Veterinary surgery : VS》1975,4(2):22-34
Seven dogs with renal allografts were studied to: (1) determine the practicality of the procedure for the treatment of end stage kidney disease in small animal medicine, and (2) measure allograft function to permit evaluation of immunosuppressive drug dosage to prevent rejection. Infection (bacterial nephritis, pneumonia, pleuritis), drug toxicity (bone marrow depression, liver degeneration and/or necrosis), and rejection of the transplants were the consistent problems. No objective measurement which would permit accurate determination of immunosuppressive drug dosage was found. Polyuria in the transplanted animals was attributed to failure to develop the interstitial osmotic gradient essential for the allografts to respond to antidiuretic hormone. Polydipsia probably was compensation for the polyuria. The results would indicate that until a major immunological breakthrough occurs in tissue transplantation, the clinical placement of a renal allograft in the dog for long term function is not practical. Prolonged function of the renal allograft has been accomplished in the dog using immunosuppressive drugs, suggesting that the procedure can be utilized for the treatment of end stage renal disease in this animal.18 Immunosuppressive drugs have inherent toxicities, of which bone marrow depression, liver and gastrointestinal tract damage are most notable.5,18,23 Ideally, minimal immunosuppression is desired to avoid drug toxicity, maintain some degree of immune competence to reduce chances of serious, if not fatal infection, and yet allow the transplanted kidney to survive in a hostile immune environment.22 There are no good measurements to determine the immunological status of patients on immunosuppressive therapy,22 consequently, such treatment is emperic; based on experimental and clinical experience. 13,18 Although the dog is a common model for renal allograft investigations, 15,18 there is limited information in the veterinary literature 3.5.6,11,14 concerning the experience of veterinary clinicians and their attempts to maintain the renal homograft. This report summarizes the author's experiment with renal transplants in the dog. 相似文献
435.
436.
The nature of the animal taxa that are the most probable candidates for an intensive, commercial aquatic animal husbandry industry is considered. A characterization is presented of those biological criteria that lend the species the necessary physiological and genetic malleability to be adapted and molded into a domesticated race. The animal cultivated must be amenable to intensive management in high-density confinements such as those now being engineered for high-yield aquaculture. Atributes considered are discussed in the context of the various aquacultural ecosystems in which the specific biotype is expected to achieve satisfactory growth and survival. Correlative with bionomic criteria, economic requirements are posed and evaluated in an effort to define a socially and financially profitable agribusiness system. Investment requirements and operating costs are considered in terms of expected returns. However, since production alone is insufficient to sustain an enterprise — i.e. the product must be sold — production costs must be judged against market values. Therefore, ultimate use or consumer acceptance criteria are incorporated into the list of essential requirements for a candidate species for aquafarming. 相似文献
437.
Shaw MR Zavaleta ES Chiariello NR Cleland EE Mooney HA Field CB 《Science (New York, N.Y.)》2002,298(5600):1987-1990
Simulated global changes, including warming, increased precipitation, and nitrogen deposition, alone and in concert, increased net primary production (NPP) in the third year of ecosystem-scale manipulations in a California annual grassland. Elevated carbon dioxide also increased NPP, but only as a single-factor treatment. Across all multifactor manipulations, elevated carbon dioxide suppressed root allocation, decreasing the positive effects of increased temperature, precipitation, and nitrogen deposition on NPP. The NPP responses to interacting global changes differed greatly from simple combinations of single-factor responses. These findings indicate the importance of a multifactor experimental approach to understanding ecosystem responses to global change. 相似文献
438.
Characterization of anthocyanins and flavonols and radical scavenging activity assays of extracts from four Chinese bayberry (Myrica rubra) varieties with different fruit colors were carried out. One dominant anthocyanin and three major flavonols were isolated by HPLC, and cyanidin-3-O-glucoside and two of three flavonols, myricetin and quercetin-3-O-rutinoside, were identified by cochromatography with authentic standards. Both DPPH* and ABTS*(+) cation assays indicated that the black varieties (Biji and Hunan) demonstrated much higher radical scavenging activities than the pink (Fenhong) and yellow (Shuijing) varieties, which may be attributed to much higher levels of anthocyanins, flavonoids, and total phenolics in the black varieties. Biji and Hunan had 6.49 and 6.52 mM Trolox equivalent antioxidant capacity (TEAC) per 100 g of fresh weight, whereas the pink (Fenhong) and yellow (Shuijing) bayberries had 1.32 and 1.31 mM TEAC/100 g. Different fruit color was reflected by the surface color and pigment extract color. Color stability of the pigment was dependent on pH, and the pigment was more stable at low pH (pH approximately 1.5). The lightness (L) increased while the chroma (C value) decreased with increase of pH until pH 5, but higher pH caused a small decrease for L and an increase for C. 相似文献
439.
Determination of the degree of succinylation in diverse modified starches by raman spectroscopy 总被引:2,自引:0,他引:2
Phillips DL Xing J Chong CK Liu H Corke H 《Journal of agricultural and food chemistry》2000,48(11):5105-5108
A method using Raman spectroscopy was recently developed for the determination of the degree of substitution of succinate in waxy maize starch. In this paper it is demonstrated that the method can be generalized to a wide range of starches of different amylose contents and botanical origins. Raman calibration sets were used to form regression equations for five types of succinylated starches, that is, waxy, regular, and two high-amylose maize samples (47 and 66% amylose, respectively) and wheat. The derived calibration curves can be used to find the degree of substitution in samples with unknown levels of succinylation. The Raman calibration lines had linear correlation coefficients of 0.995 or better and enable the fast and nondestructive determination of the degree of substitution of succinate for different types of starches with minimal sample preparation. Also discussed is the potential utility of Raman spectroscopy to simultaneously determine the degree of substitution of succinate and amylose content, using previously determined calibration curves developed for the amylose content of maize starches. 相似文献
440.
Harold M. van Es 《Geoderma》1993,60(1-4):187-199
Model simulation of water and chemical transport requires information on soil hydraulic properties. Recently, independent parameterization methods have been developed to characterize soil type, tillage, temporal and spatial effects of soils. This study determines the relative magnitude of tillage-induced, temporal (yearly and seasonal), and spatial (within fields and between rows) variability in a combined analysis of soil infiltration in an agricultural field and evaluates the appropriateness of various parameterization scenarios. Infiltration measurements were obtained in the row and interrow position under plow-tilled and ridge-tilled corn (Zea mays L.) in four replicates on multiple dates in a wetter (1990) and dryer year (1991). Measurements exhibited significant temporal variability within a growing season, especially in a dry year under plow till when soil cracking resulted in higher infiltration. Position with respect to the row was the most significant source of variability under ridge till, but not under plow till. Row and interrow differences in a ridge-tilled soil are the result of dense soil and lack of disturbance in the interrow. Yearly variations and field variability were relatively low. Differences between tillage practices were primarily expressed in variable susceptibility to spatial and temporal variation. Adequate parameterization of soil infiltration on agricultural fields requires recognition of various sources of variability under different tillage management systems, weather and climatic conditions, and soil types. High intrinsic variability of soil infiltration must be accounted for through increased sampling (e.g. duplicate measurements) and the use of stochastic methods. 相似文献