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151.
A rapid, quantitative assay for titration of bovine virus diarrhoea-mucosal disease virus 总被引:1,自引:0,他引:1
An end point dilution microtitration assay is described that can be used for the titration of both cytopathic and non-cytopathic isolates of bovine virus diarrhoea-mucosal disease virus. Indirect immunofluorescence is used to detect infected MDBK cells in the wells of Terasaki plates. The virus titre is derived from the number of uninfected wells, using the Poisson distribution. The assay is simple, fast and economical. Titres of cytopathic virus determined by the microtitration assay and standard plaque assay are equivalent. 相似文献
152.
SUMMARY A 19-month-old pony gelding was presented with chronic renal failure, after deteriorating progressively during the preceding 3 months. There was pronounced azotaemia, hyponatraemia and hypochloraemia, but plasma calcium and phosphorus levels were normal. At autopsy both kidneys were small and nodular and were characterised by collapsed segments of cortex and medulla interspersed with areas of pale tissue. The latter showed glomerular immaturity associated with a range of degenerative processes involving the glomeruli and tubules. The condition bore many similarities to that of renal cortical dysplasia in other species. 相似文献
153.
The degradation of the wild oat herbicide flamprop-methyl [methyl DL -N-benzoyl-N-(3-chloro-4-fluorophenyl)alaninate] in four soils has been studied under laboratory conditions using 14C-1abelled samples. The flamprop-methyl underwent degradation more rapidly than its analogue flamprop-isopropyl. However, similar degradation products were formed, namely the corresponding carboxylic acid and 3-chloro-4-fluoroaniline. The latter compound occurred mainly as ‘bound’ forms although evidence was obtained of limited ring-opening to give [14C]carbon dioxide. The time for depletion of 50% of the applied herbicide was approximately 1-2 weeks in sandy loam, clay and medium loam soils and 2-3 weeks in a peat soil. 相似文献
154.
Abstract. Water samples from ditches draining small upland areas in mid-Wales were collected before, during and after the improvement of the pasture using two different cultivation techniques. The samples were analysed for nitrogen, phosphorus, potassium and pH. The greatest release was associated with disc harrowing where nitrogen, in its nitrate form, exceeded European Economic Community maximum recommended concentrations for potable water supply for two weeks. Smaller losses of nitrogen, in the ammonium form, and of ortho-phosphate were observed following a minimum cultivation technique. It is concluded that, on a scale normally associated with upland Britain, pasture improvement is not likely to deteriorate significantly the quality of runoff within water supply catchments. This is confirmed by the results obtained from monitoring streamflow from catchments in which some degree of pasture improvement had been undertaken in the past. 相似文献
155.
Two unrelated adult dogs developed idiopathic, acute-onset, bilateral total blindness. The ophthalmoscopic changes were minimal and no electroretinographic response could be detected in either dog. The retinas were examined ultrastructurally 10 days (dog 1) and two-and-a-half months (dog 2) after they became blind. There was widespread loss of the outer segments of rod and cone photoreceptors. Where the outer segments persisted, there was marked tubulovesicular change with loss of normal orientation in their lamellae. Second order neurons (bipolar cells) and ganglion cells were unaffected. The cause of this selective and massive disruption of rod and cone endings was not established, but acute toxicity is proposed as a possible mechanism. 相似文献
156.
157.
In this paper an overview of principles involved in nuclear imaging is presented. Nuclear images are picotrial representations of the distribution of systemically administered radiopharmaceuticals. Although many radionuclides are available. 99mTc is the most commonly used radionuclide, either in ionic form (99mTcO4) or bound to other pharmaceuticals. Distribution within the body is by physiologic processes, dependent on the radiopharmaceutical used. Most distribution processes are organ specific rather than disease specific. Scintillation detectors are used to record the activity and disribution of an administered radiopharmaceutical and to create a representative image on film. A rectilinear scanner is an imaging system with a small detector that moves systematically, point by point, over an organ of interest. A gamma (scintillation) camera is an imaging system with a large stationary detector that encompasses a larger field of view. Nuclear imaging provides information based primarily on physiologic principles, and radiography provides infromation based primarily on anatomic or geometric principles. Examples of some scanning procedures are discussed. 相似文献
158.
M D Willard R E Roberts N Allison R B Grieve K Escher 《Journal of the American Veterinary Medical Association》1988,192(7):913-916
During a 6-month period, 108 sexually mature stray cats were euthanatized at a humane shelter in Alabama. Aelurostrongylus abstrusus was identified in 20 of the cats (18.5%) by Baermann fecal examination, necropsy, or histologic examination. The Baermann fecal examination was a more sensitive test for aelurostrongylosis than was necropsy or histologic examination. Thoracic radiography was useful in identifying infected cats, but was a less sensitive and more nonspecific method of detection than was the fecal examination. Changes in CBC and serum protein concentrations were not helpful identifying cats with aelurostrongylosis. Six of 17 (35%) heartworm-free, lungworm-infected cats had antibodies to Dirofilaria immitis, as determined by an ELISA method, but none had circulating D immitis antigen, as determined by an ELISA method. Three (2.8%) cats had D immitis. Two of the heartworm-infected cats had no detectable antemortem radiographic or clinicopathologic evidence of the infection. Results of ELISA were positive for antibodies to adult heartworms in 2 cats and for circulating heartworm antigen in 2 cats. One cat that had only one heartworm had no detectable circulating heartworm antigen. 相似文献
159.
160.