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921.
Nitrogen and potassium fertilization of potatoes: Evaluating nutrient element interactions in petioles with response surfaces 总被引:1,自引:0,他引:1
D. W. James R. L. Hurst D. T. Westermann T. A. Tindall 《American Journal of Potato Research》1994,71(4):249-265
We studied the effects of fertilizer N and K rates on the nutrient concentrations in petioles of Russet Burbank potato grown on a low-K, low-Cl, highly calcareous Millville silt loam soil. Phosphate and CaSO4 were applied uniformly so that P and S did not limit plant growth. An incomplete factorial experimental design, utilizing 14 combinations of fertilizer N and K, including two forms of K, was used to develop a multi-dimensional regression model. This model was then used to produce response surfaces as an aid to analysis of the results and to illustrate the fertilizer treatment effects and their interactions on petiole chemistries. Nitrogen, K and Cl fertilizers had complex effects on petiole concentrations of NO3-N, SO4-S, Cl, K, Ca and Mg. Nitrate-N and Cl were mutually antagonistic. Soil N had a large positive effect on petiole K and Mg levels and, to a lesser extent, petiole Ca levels. There was competition between K and Mg in petiole concentration. The sum of K, Ca and Mg was essentially constant across fertilizer treatments and sampling times. The sum of NO3-N, SO4-S and Cl was highly variable. The ratio of cations to anions ranged between three and five across fertilizer treatments and sampling times. The data indicate that calibration of the major nutrient element concentrations in potato petioles, as a guide to fertilization, requires knowledge of background soil fertility conditions with respect to N, K, Cl, Ca and Mg, and an understanding of the antagonisms and synergisms among these elements. 相似文献
922.
James A. Orsini 《Journal of Equine Veterinary Science》2011,31(4):194-201
Laminitis is a disease that represents a loss of the normal homeostatic mechanisms that control the day-to-day function of the distal phalanx. The degree or severity to which homeostasis is affected is directly related to the severity and the final outcome for the equine patient. A systematic approach including the physical examination, digital radiography, venography, and newer techniques such as computer tomography and magnetic resonance imaging can assist the clinician in developing a prognosis for the acute and chronic laminitis case. How quickly we are able to return the foot back to a normal state of homeostasis or the response to treatment is important as a predictive value for outcome. 相似文献
923.
Gershenson RT Melidone R Sutherland-Smith J Rogers CL 《Journal of the American Animal Hospital Association》2011,47(1):45-49
A 2 yr old spayed female German shepherd presented with a chief complaint of acute onset paraparesis and weight loss. At presentation, the dog was pyrexic, nonambulatory, and had generalized muscle wasting. Neurolocalization was consistent with a thoracolumbar spinal cord lesion. An abdominal ultrasound was performed and revealed a focal dilation (4 cm) of the terminal aorta with evidence of blood stasis consistent with an aortic aneurysm. The dog was euthanized shortly after admission to the hospital and a post mortem examination was performed. Fungal organisms were identified in the aortic aneurysm as well as from the thoracic vertebrae, mesenteric lymph nodes, axillary lymph nodes, spleen, kidneys, liver, lungs, and heart. Although the morphology was consistent with Candida spp., immunohistochemistry and PCR could not definitively identify the causative organism. Mycotic aortic aneurysms are a rare finding in humans and have not been previously reported in the dog. To the authors' knowledge, this is the first known report of an aortic aneurysm associated with systemic fungal infection in a dog. 相似文献
924.
Isabelle A. Kagan Brett H. Kirch Craig D. Thatcher James R. Strickland Chris D. Teutsch François Elvinger R. Scott Pleasant 《Journal of Equine Veterinary Science》2011,31(8):488-497
Seasonal and diurnal changes in water-soluble carbohydrates (WSC) and ethanol-soluble carbohydrates (ESC), as well as in chromatographic profiles of the sugars comprising these categories, were studied in orchardgrass pastures at one location in the Piedmont region of Virginia. Grass from four experimental plots was sampled weekly in the morning and afternoon over an 8-week period (early to late spring). Tissue was air-dried to simulate hay, or frozen to preserve the sugar profiles of fresh pasture. WSC and ESC were assayed colorimetrically. To profile sugars, boiled-water extracts were separated by high-performance liquid chromatography coupled to pulsed amperometric detection. Fructan, glucose, fructose, and sucrose were quantified by high-performance liquid chromatography. All sugar concentrations were highest in the early spring in both fresh and dried tissue. Fructan chain length was highest in early spring as well. Significant diurnal differences were observed for WSC and fructan, on some dates (P < .0001 and P = .024, respectively), and for ESC, glucose, and sucrose averaged over the entire period (P = .0002, .004, and <.0001, respectively). Sucrose was barely detectable in fresh tissue but reached 1.6% to 12% dry matter in dried tissue. These results demonstrate changes in orchardgrass carbohydrates over a season, within a day, and between dried and fresh herbage. Understanding these changes may be helpful in the management of horses with a history of insulin resistance and laminitis. 相似文献
925.
926.
Mansfield CS James FE Steiner JM Suchodolski JS Robertson ID Hosgood G 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(3):419-425
Background: The putative role of the gut in amplification of systemic inflammation in acute pancreatitis is gaining credence, and intraluminal nutrition has been shown to decrease inflammation in experimental models of pancreatitis. Prepyloric feeding often is used in people with acute pancreatitis, but has not been evaluated in dogs. Hypothesis: Early intervention with enteral nutrition (EN) delivered proximal to the pylorus will be well tolerated in dogs with acute pancreatitis and provide justification for further larger trials. Animals: Ten dogs with severe acute pancreatitis in an open‐label, prospective pilot study. Methods: Dogs were treated with plasma transfusion and standard care, and then consecutively assigned to receive either EN via esophagostomy tube feeding or parenteral nutrition (PN). Outcome was used to determine optimal study size for future studies, and complications were compared between the 2 groups. Results: A significantly greater number of vomiting or regurgitating episodes occurred in dogs receiving PN. The dogs receiving EN did not demonstrate any noticeable postprandial pain. There were more catheter‐related complications in the PN group. There was no difference in outcome between the 2 treatments, and 43 dogs for each treatment would be required in future studies to determine a difference in outcome. Conclusions and Clinical Relevance: Early EN delivered proximal to the pylorus is well tolerated in dogs with severe pancreatitis and resulted in fewer complications than PN. Prospective trials in a larger cohort are justified to fully establish the potential benefit of early EN, preferably compared with minimal enteral nutrition. 相似文献
927.
An UHPLC-PDA-ESI/HRMS/MS(n) profiling method was used for a comprehensive study of the phenolic components of red mustard greens ( Brassica juncea Coss variety) and identified 67 anthocyanins, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives. The glycosylation patterns of the flavonoids were assigned on the basis of direct comparison of the parent flavonoid glycosides with reference compounds. The putative identifications were obtained from tandem mass data analysis and confirmed by the retention time, elution order, and UV-vis and high-resolution mass spectra. Further identifications were made by comparing the UHPLC-PDA-ESI/HRMS/MS(n) data with those of reference compounds in the polyphenol database and in the literature. Twenty-seven acylated cyanidin 3-sophoroside-5-diglucosides, 24 acylated cyanidin 3-sophoroside-5-glucosides, 3 acylated cyanidin triglucoside-5-glucosides, 37 flavonol glycosides, and 10 hydroxycinnamic acid derivatives were detected for the first time in brassica vegetables. At least 50 of them are reported for the first time in any plant materials. 相似文献
928.
929.
Tokateloff N Carmalt J Manning S 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(5):519-523
A horse was initially diagnosed with hemarthrosis and desmitis of the long medial collateral ligament of the right tarsus and later developed prominent enthesiophytosis at the site of insertion of the ligament's deep portion. Hemarthrosis due to intra- or peri-articular pathology can cause recurrent lameness, even without evident external trauma. 相似文献
930.