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21.
The mean percentage of cells forming rosettes with 2-aminoethyl isothiouronium bromide-treated sheep erythrocytes (EAETRFC) in the peripheral blood of 10 horn cancer-affected cattle (40.05 +/- 2.91) was significantly low in comparison to the value in unaffected control animals (58.61 +/- 1.68). Immunotherapy with a saline phenol extract of allogeneic tumour tissue resulted in a gradual increase in the mean percentage of EAETRFC on each subsequent week. The increase was statistically significant from the second week onwards and on the sixth week, the percentage of EAETRFC in horn cancer affected cattle (56.80 +/- 1.38) closely approximated the value in unaffected controls.  相似文献   
22.
OBJECTIVE: To investigate the relationship between diet, growth rate and the presence of caudal cervical malformation in Doberman puppies. DESIGN: A prospective study of 15 Dobermann puppies from three unrelated litters, aged from 0 to 16 weeks. PROCEDURE: The growth rate in terms of body weight gain and increase in ulna length were measured weekly for all puppies. In addition the nutritional quality of the diets was assessed. Radiographs of the cervical spine were taken at 6 and between 12 and 16 weeks of age and examined for the presence of caudal cervical vertebral malformation. A mixed model for repeated measures data was used to investigate the relationship between the growth rate of the puppies and the fixed effects age, dam, diet, gender and presence of caudal cervical malformation. RESULTS: Five of the puppies had changes consistent with caudal cervical malformation. The diets fed were either balanced or transiently deficient in protein, calcium, phosphorus and/or magnesium. There was no significant association between growth rate and the variables dam, gender and the presence of caudal cervical vertebral malformation. There was no significant association between diet and increase in ulna length, but a trend existed between body weight gain and the feeding of a balanced diet (P = 0.0672). CONCLUSION: Caudal cervical vertebral changes can be detected radiographically as early as 6 weeks of age in some Dobermann puppies. A balanced diet and growth rate are not significant factors in its initial development.  相似文献   
23.
Ten common kestrels (Falco tinnunculus) were used for this falcon herpes vaccine experiment. Four kestrels were subcutaneously given 1 ml of an attenuated falcon herpesvirus that had originally been isolated from the liver of an American prairie falcon (Falco mexicanus). This virus was then passaged 100 times on chicken embryo fibroblast cells (CEF-cells). Another 4 kestrels were given subcutaneously an inactivated falcon herpesvirus vaccine derived from the same American field strain. This vaccine was concentrated, inactivated by heat and betapropiolactone and emulsified in complete Freund's adjuvans. Two further kestrels served as controls and were not vaccinated. Twenty-one days after vaccination, all 10 kestrels were challenged with passage 3 of the American falcon herpesvirus. The 2 control kestrels died 6 days after challenge and 3 of those given the inactivated herpes vaccine died 9 days after challenge, with typical lesions of herpesvirus inclusion body hepatitis. Before the vaccination experiment, all 10 kestrels were free of serum neutralising antibodies to the falcon herpesvirus. Twenty-one days after vaccination, all 4 kestrels vaccinated with the attenuated vaccine, and one vaccinated with the killed vaccine, had seroconverted, having shown no symptoms to the challenge with a low passage virulent American herpesvirus strain. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there is no danger for any other birds from the attenuated herpesvirus vaccine. This experiment clearly shows that an attenuated falcon herpesvirus vaccine can protect kestrels from fatal inclusion body hepatitis.  相似文献   
24.
This survey assessed the feline transfusion practices at the University of Berlin from 1998 to 2001 in regard to patient population, indications, efficacy, and transfusion reactions. Blood was obtained from seven healthy in-house donors and 127 mostly indoor client-owned pet cats. Over a 3-year period 91 cats were transfused with blood type compatible blood. The blood was fresh (within 8 h of collection) or stored no longer than 15 days. Transfusions were required because of blood loss anaemia (n=40), haemolytic anaemia (n=13), ineffective erythropoiesis (n=35), hypoproteinaemia (n=2) or coagulopathy (n=2). The anaemic cats had a pretransfusion haematocrit of 5-20% (m [median]=13), and received one to six transfusions (m=1). The survival rates of the anaemic cats at 1 and 10 days after transfusion were 84 and 64%, respectively. None of the deaths appeared to be related to transfusion reactions. The major crossmatch, undertaken before 117 transfusions, was incompatible for eight cats. All except for one had previously been transfused. Lysis of transfused cells in six cases resulted in a less than expected haematocrit rise and an increase in serum bilirubin. Transient mild transfusion reactions were only noted in two cats during the second or third transfusion. In conclusion, with proper donor selection and appropriate compatibility screening, blood transfusions are well tolerated, appear effective, and may increase chances of survival.  相似文献   
25.
OBJECTIVES: To determine the distribution of blood types and to estimate the proportion of matings at risk for neonatal isoerythrolysis in non-pedigree domestic cats. METHODS: The present survey determined the frequency of blood types in 301 cats from four distinct regions of Turkey. Ethylenediaminetetraacetic acid-anticoagulated blood samples were typed by simple tube and slide agglutination assays. Serum obtained from type B cats and an anti-B solution, prepared with Triticum vulgaris, were used to determine type A and type B blood, respectively. RESULTS: Of the 301 cats typed, 220 had type A blood, 74 had type B and seven had type AB. There was a significant difference (P<0.01) between the locations of the cats, with fewer type B cats in the eastern than in the western parts of Turkey. Risk for the development of neonatal isoerythrolysis due to A-B mismatch was estimated to be 18.6 per cent. CLINICAL SIGNIFICANCE: The overall type B frequency in Turkish domestic cats is high. Thus, untyped transfusions in these cats carry a high risk of life-threatening acute haemolytic transfusion reactions and neonatal isoerythrolysis. It is therefore strongly recommended that blood typing be performed before breeding or transfusing in order to minimise blood type incompatibility risks.  相似文献   
26.
DNA diagnosis in veterinary medicine: II. Polymerase chain reaction (PCR)   总被引:1,自引:0,他引:1  
DNA diagnostic has become very important for genetic and infectious diseases. With a new method, called the polymerase chain reaction (PCR), specific pieces of genomes from viruses, bacteria, parasites or even cells can be amplified more than hundred million fold in a very short time period. For the following reasons this opens a new dimension in diagnostics: (1) The technique is so sensitive that a single virus, bacterium, parasite or cell is sufficient to be detected provided part of its nucleic acid sequence is known. (2) The material does neither need to be fresh nor be stored under special conditions since the nucleic acids are much more stable than e.g. enzymes or other proteins. (3) The method is quicker than the usual immunodetection methods. (4) The polymerase chain reaction has been standardized recently so that it can be carried out in diagnostic laboratories. The purpose of this minireview is to give an introduction into the basic technique and to mention possible and already existing applications in veterinary medicine.  相似文献   
27.
A single experiment with a completely randomized design was conducted to evaluate the effects of long- or short-term exposure to a calf identified as persistently infected with bovine viral diarrhea virus (PI-BVD) on feedlot performance and carcass characteristics of freshly weaned, transport-stressed beef heifers. Two hundred eighty-eight heifers that had been vaccinated for BVD before weaning and transport were processed and given a metaphylactic antibiotic treatment at arrival and were fed common receiving, growing, and finishing diets for a 215-d period. Treatments were designed to directly or adjacently expose the cattle to a PI-BVD heifer. Directly exposed treatments were 1) negative control with no PI-BVD calf exposure (control), 2) PI-BVD calf commingled in the pen for 60 h and then removed (short-term exposure), and 3) PI-BVD calf commingled in the pen for the duration of the study (long-term exposure); and spatially exposed treatments were 1) negative control with no PI-BVD calf exposure (adjacent pen control), 2) PI-BVD calf commingled in the adjacent pen for 60 h and then removed (adjacent pen short-term exposure), and 3) PI-BVD calf commingled in the adjacent pen for the duration of the study (adjacent pen long-term exposure). Exposure to a PI calf transiently (60 h) or for the duration of the feeding period (215 d) did not affect (P > or = 0.25) final BW compared with heifers that were not exposed. Neither period nor overall DMI was affected (P > or = 0.37) by PI-BVD calf exposure, and no differences (P > or = 0.44) were observed between short- and long-term exposed heifers in the direct or spatially exposed groups. Likewise, total trial ADG was not affected (P > or = 0.36) and overall efficiency of gain (P > or = 0.19) was unaffected by PI-BVD calf exposure in the direct or spatially exposed groups. The results from this study suggest that exposing previously vaccinated, freshly weaned, transport- stressed beef calves to a calf that is persistently infected with bovine viral diarrhea virus has little, if any, marked effects on health, performance, or carcass characteristics.  相似文献   
28.
29.
Objective: To describe a technique used for reduction and internal fixation of sacral fractures in cattle. Study Design: Case series. Animals: Three heifers aged 19–32 months with deformation of the tail head and tail paralysis attributable to a closed fracture of S5 or S4 and S5. Methods: Fractures were reduced and repaired under general anesthesia. A narrow, 6–10‐hole, locking compression plate (LCP) was placed on the spinous processes of S5 and the first coccygeal (Co1) using 5.0 mm locking head screws. Follow‐up inquiries were made by telephone (3/3), and cows were examined clinically and radiographically 2 (1 cow) to 9 (1cow) months postoperatively. Results: No complications were encountered. The range of movement of the tail improved so that soiling of the tail during defecation was no longer a problem. In all heifers, the normal top line was restored and there was no narrowing of the pelvic canal. Unassisted calving occurred in all heifers, and follow‐up radiographs for 2 cows showed complete fracture healing. Conclusion: LCP‐osteosynthesis of the spinous processes provided sufficient stability for internal fixation of sacral fractures. Marked improvement in tail function occurred postoperatively without decompression by laminectomy.  相似文献   
30.
The agar-gel immunodiffusion test was used to evaluated 35 dogs with histopathologically confirmed blastomycosis and 98 dogs without blastomycosis. The test had a sensitivity of 91% and a specificity of 96%. Thirteen of the dogs treated for blastomycosis were tested at 6 to 33 months after treatment with amphotericin B. Ten of 13 dogs became seronegative and 3, though clinically normal, remained seropositive at 19, 20, and 20 months, respectively, after amphotericin treatment.  相似文献   
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