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991.
Eight horses were allotted to 2 groups, each of 4 horses. All horses were given 100 plastic markers intragastrically via a nasogastric tube. One group of animals (control group) was not given medication after marker administration. The other group (test group) was given neostigmine methylsulfate (0.022 mg/kg of body weight) in the subcutaneous tissue at the time of marker administration and 30, 60, and 90 minutes later. All horses were killed 135 minutes after marker administration to locate the beads in the gastrointestinal tract. Gastric emptying of the markers was significantly delayed (P less than 0.05) in horses given neostigmine methylsulfate. 相似文献
992.
Investigations of toxicity episodes involving chemotherapeutic agents in Victorian poultry and pigeons 总被引:1,自引:0,他引:1
This series of case reports details observations on toxicity episodes in poultry due to a variety of chemotherapeutic agents. These problems arose owing to overdosage, variation in species susceptibility, potentiation of the toxic effects of one substance by the presence of another substance, and particular disease or other on-farm factors. Ignorance and accident were responsible for some of these situations. The episodes involved monensin, salinomycin, nicarbazin, sulphaquinoxaline, dinitolmide, dimetridazole, nitrofurans, streptomycin, and 3-nitro-4-hydroxyphenylarsonic acid. 相似文献
993.
994.
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996.
During October to December 1986, 365 traditional cattle herds in four provinces in Zambia were inspected and the owners interviewed. Information was collected on the treatment, management and disposal of cases of bovine dermatophilosis and on the effects of this disease on productivity for 1985. The contemporary financial cost per case of treatment and/or premature disposal, slaughter or death to the owners was K. 202 (US$ 91). The cost due to draft oxen being affected was estimated at K. 428 (US$ 193) per affected ox. The cost of reduced milk production, replacing affected cows and calf deaths, directly or indirectly from bovine dermatophilosis, was estimated at K. 132 (US$ 78) per affected milking cow. The total annual national cost of bovine dermatophilosis in 1985 was conservatively estimated to be some K. 6.9 million, (US$ 3 million). There were indications that the true financial cost in 1985 may have been up to 1.8 times the estimated cost. 相似文献
997.
Persistence of avian influenza viruses in water 总被引:9,自引:0,他引:9
Persistence of five avian influenza viruses (AIVs) derived from four waterfowl species in Louisiana and representing five hemagglutinin and neuraminidase subtypes was determined in distilled water at 17 C and 28 C. Infectivity was determined over 60 days by microtiter endpoint titration. One AIV was tested over 91 days at 4 C. Linear regression models for these viruses predicted that an initial concentration of 1 x 10(6) TCID50/ml water could remain infective for up to 207 days at 17 C and up to 102 days at 28 C. Significant differences in slopes for AIV persistence models were detected between treatment temperatures and among viruses. Results suggest that these viruses are adapted to transmission on waterfowl wintering habitats. Results also suggest a potential risk associated with waterfowl and domestic poultry sharing a common water source. 相似文献
998.
R D Jolly R D Martinus A Shimada I M Fearnley D N Palmer 《Canadian journal of veterinary research》1990,54(1):15-21
The pathogenesis of the ceroid-lipofuscinoses, inherited storage diseases of children, was studied in an ovine model. This was shown to have clinical and pathological features most in common with the late infantile and juvenile human forms of the disease. The ability to study sequential changes allowed the retinal lesions to be described as a dystrophy of photoreceptor outer segments which preceded loss of the photoreceptor cells. An early decrease in amplitude of the c-wave electroretinograph was attributed to a decrease in the transpigment epithelial component. The decreased a- and b-wave amplitudes were attributed to the changes in and loss of, photoreceptor cells. The chemical components of isolated storage cytosomes were analyzed and shown to consist mostly of protein. Sequence analysis of the dominantly stored protein showed that it was identical to the DCCD reactive proteolipid or subunit c of mitochondrial adenosine triphosphate synthase and that it comprised approximately 50% of storage material. Based on the adage that the dominantly stored species should reflect the underlying biochemical anomaly, it was concluded that it was of pathogenic significance. This highly hydrophobic protein tends to extract with lipids in chloroform/methanol and is thus known as a proteolipid. Some of the remainder of the stored proteins also had this characteristic. It was concluded that ovine ceroid-lipofuscinosis was a proteinosis, more specifically a proteolipid proteinosis and as such it forms the prototype of a new class of storage diseases. Recognition of the nature of the dominantly stored chemical species has helped understanding of a variety of chemical and physical characteristics attributed to the whole pigment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
The isoelectric focusing properties of serum alkaline phosphatase in disease and following prednisolone and phenylbutazone administration in the horse. 下载免费PDF全文
This study was undertaken to ascertain if the isoelectric focusing pattern of serum alkaline phosphatase (AP) from sick horses with high activity is useful for determining its tissue origin. The effect of oral prednisolone and phenylbutazone therapy on this enzyme in healthy horses was also investigated. The sick horses were divided into three groups: hepatic, intestinal and miscellaneous. All sera had approximately thirteen bands of AP activity when focused on agarose gels with a pH gradient of 3.5 to 9.5. All the horses in the liver disease group had greater than 65% of enzyme activity in bands 3 to 7 (counted from the anode) whereas the other two groups had at least 30% and up to 80% of activity in bands 8 to 13. This was true even in the several cases of primary intestinal disease that had additional biochemical evidence of liver damage. All bands were heat sensitive indicating that little if any AP was of small intestinal or renal origin. Oral prednisolone and phenylbutazone for 20 and 12 days respectively had no affect on serum AP activity or isoelectric pattern. We concluded that the AP in bands 3 to 7 is of liver origin but the origin of bands 8 to 13 remains undetermined although small intestinal or renal origin is unlikely. Isoelectric focusing of serum AP shows promise in differentiating cases of primary from secondary liver disease but further studies are required correlating serum patterns and tissue patterns in animals with diseases. 相似文献
1000.
Comparison of the complement-fixation and agar gel immunodiffusion tests for diagnosis of subclinical bovine paratuberculosis 总被引:4,自引:0,他引:4
D M Sherman J M Gay D S Bouley G H Nelson 《American journal of veterinary research》1990,51(3):461-465
The performance of the serum complement fixation (CF) test was compared with that of a serum agar gel immunodiffusion (AGID) test on 74 subclinically infected and 154 uninfected cattle in 6 commercial midwestern dairy herds with Mycobacterium paratuberculosis infection and on 30 cattle in a herd that was free of infection. Infection status of cattle within herds was established by performance of a series of 3 or more fecal cultures and of ileocecal lymph node cultures of culled cattle. In cattle with subclinical infection detected by culturing, the sensitivity estimates of the CF and AGID tests were 10.8% (3.6% SE) and 18.9% (4.5% SE), respectively. In the cattle classified as disease free, the specificity estimates of the CF and AGID tests were 97.4% (1.3% SE) and 99.4% (0.6% SE), respectively. Neither set of estimates was significantly different. Negative test results obtained with the use of either test in apparently normal cattle from suspect herds should be interpreted with caution because both tests suffer from low sensitivities in subclinically infected animals. However, the AGID test may be more useful in regulatory situations in which the CF test is currently used because the AGID test is easier to perform and to interpret. 相似文献