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941.
Derksen FJ Williams KJ Uhal BD Slocombe RF de Feijter-Rupp H Eberhart S Berney C Robinson NE 《Equine veterinary journal》2007,39(4):334-339
REASONS FOR PERFORMING STUDY: Exercise-induced pulmonary haemorrhage (EIPH) occurs in the majority of horses performing strenuous exercise. Associated pulmonary lesions include alveolar and airway wall fibrosis, which may enhance the severity of EIPH. Further work is required to understand the pulmonary response to blood in the equine airways. OBJECTIVES: To confirm that a single instillation of autologous blood into horse airways is associated with alveolar wall fibrosis, and to determine if blood in the airways is also associated with peribronchiolar fibrosis. METHODS: Paired regions of each lung were inoculated with blood or saline at 14 and 7 days, and 48, 24 and 6 h before euthanasia. Resulting lesions were described histologically and alveolar and airway wall collagen was quantified. RESULTS: The main lesion observed on histology was hypertrophy and hyperplasia of type II pneumocytes at 7 days after blood instillation. This lesion was no longer present at 14 days. There were no significant effects of lung region, treatment (saline or autologous blood instillation), nor significant treatment-time interactions in the amount of collagen in the interstitium or in the peribronchial regions. CONCLUSION: A single instillation of autologous blood in lung regions is not associated with pulmonary fibrosis. POTENTIAL RELEVANCE: Pulmonary fibrosis and lung remodelling, characteristic of EIPH, are important because these lesions may enhance the severity of bleeding during exercise. A single instillation of autologous blood in the airspaces of the lung is not associated with pulmonary fibrosis. Therefore the pulmonary fibrosis described in EIPH must have other causes, such as repetitive bleeds, or the presence of blood in the pulmonary interstitium in addition to the airspaces. Prevention of pulmonary fibrosis through therapeutic intervention requires a better understanding of these mechanisms. 相似文献
942.
An evaluation of scrapie surveillance in the United States 总被引:1,自引:1,他引:0
Lynn T Grannis J Williams M Marshall K Miller R Bush E Bruntz S 《Preventive veterinary medicine》2007,81(1-3):70-79
Animal health surveillance systems should reflect national disease control priorities and promote the best use of public resources by maximizing effectiveness and efficiency. A surveillance system should be routinely evaluated to assess the degree to which the system accomplishes these goals, fulfills its stated objectives, and meets accepted surveillance standards. In the United States, there are a number of disparate endemic disease surveillance and eradication programs. The National Animal Health Surveillance System is a federal initiative designed to combine animal health surveillance and monitoring activities into a comprehensive and coordinated system. A protocol has been developed to facilitate the evaluation of animal health surveillance systems and investigate opportunities for coordination between the different surveillance and eradication programs. The evaluation protocol was based largely on protocols developed for public health but adapted for the specific needs and goals of animal health surveillance. The evaluation process was designed to identify program strengths and areas for improvement and facilitate the system's adaptability to changing situations. The evaluation protocol was applied to the scrapie surveillance system in the United States; scrapie surveillance was found to be an important part of surveillance for transmissible spongiform encephalopathies. Results from the evaluation of sensitivity, sampling methods and representativeness are presented. 相似文献
943.
Paiba GA Roberts SR Houston CW Williams EC Smith LH Gibbens JC Holdship S Lysons R 《Preventive veterinary medicine》2007,81(1-3):117-134
Surveillance information is most useful when provided within a risk framework, which is achieved by presenting results against an appropriate denominator. Often the datasets are captured separately and for different purposes, and will have inherent errors and biases that can be further confounded by the act of merging. The United Kingdom Rapid Analysis and Detection of Animal-related Risks (RADAR) system contains data from several sources and provides both data extracts for research purposes and reports for wider stakeholders. Considerable efforts are made to optimise the data in RADAR during the Extraction, Transformation and Loading (ETL) process. Despite efforts to ensure data quality, the final dataset inevitably contains some data errors and biases, most of which cannot be rectified during subsequent analysis. So, in order for users to establish the 'fitness for purpose' of data merged from more than one data source, Quality Statements are produced as defined within the overarching surveillance Quality Framework. These documents detail identified data errors and biases following ETL and report construction as well as relevant aspects of the datasets from which the data originated. This paper illustrates these issues using RADAR datasets, and describes how they can be minimised. 相似文献
944.
The prevalence of disease in many populations is often low. For example, the prevalence of tuberculosis, brucellosis, and bovine spongiform encephalopathy range from 1 per 100,000 to less than 1 per 1,000,000 in many countries. When an outbreak occurs, epidemiological investigations often require comparing the prevalence in an exposed population with that of an unexposed population. To determine if the level of disease in the two populations is significantly different, the epidemiologist must consider the test to be used, desired power of the test, and determine the appropriate sample size for both the exposed and unexposed populations. Commonly available software packages provide estimates of the required sample sizes for this application. This study shows that these estimated sample sizes can exceed the necessary number of samples by more than 35% when the prevalence is low. We provide a Monte Carlo-based solution and show that in low-prevalence applications this approach can lead to reductions in the total samples size of more than 10,000 samples. 相似文献
945.
Equine multinodular pulmonary fibrosis: a newly recognized herpesvirus-associated fibrotic lung disease 总被引:1,自引:0,他引:1
Williams KJ Maes R Del Piero F Lim A Wise A Bolin DC Caswell J Jackson C Robinson NE Derksen F Scott MA Uhal BD Li X Youssef SA Bolin SR 《Veterinary pathology》2007,44(6):849-862
Pulmonary fibrosis and interstitial lung disease are poorly understood in horses; the causes of such conditions are rarely identified. Equine herpesvirus 5 (EHV-5) is a gamma-herpesvirus of horses that has not been associated with disease in horses. Pathologic and virologic findings from 24 horses with progressive nodular fibrotic lung disease associated with EHV-5 infection are described and compared with 23 age-matched control animals. Gross lesions consisted of multiple nodules of fibrosis throughout the lungs. Histologically, there was marked interstitial fibrosis, often with preservation of an "alveolar-like" architecture, lined by cuboidal epithelial cells. The airways contained primarily neutrophils and macrophages. Rare macrophages contained large eosinophilic intranuclear viral inclusion bodies; similar inclusion bodies were also found cytologically. The inclusions were identified as herpesviral-like particles by transmission electron microscopy in a single horse. In situ hybridization was used to detect EHV-5 nucleic acids within occasional macrophage nuclei. With polymerase chain reaction (PCR), the herpesviral DNA polymerase gene was detected in 19/24 (79.2%) of affected horses and 2/23 (8.7%) of the control horses. Virus genera-specific PCR was used to detect EHV-5 in all of the affected horses and none of the control horses. EHV-2 was detected in 8/24 (33.3%) of affected horses and 1/9 (11.1%) of the control horses. This disease has not been reported before, and the authors propose that based upon the characteristic gross and histologic findings, the disease be known as equine multinodular pulmonary fibrosis. Further, we propose that this newly described disease develops in association with infection by the equine gamma-herpesvirus, EHV-5. 相似文献
946.
Salimi-Bejestani MR Daniel R Cripps P Felstead S Williams DJ 《Veterinary parasitology》2007,149(3-4):290-293
Antibodies against Fasciola hepatica were detected in serum and individual milk samples of dairy cattle using an ELISA. Percentage positivity (PP) values in milk samples were related to serum PP values and were not influenced by days into lactation. The correlation coefficient between serum and individual milk samples was highly significant (r=0.84, P<0.005). The correlation coefficient between herd seroprevalence and herd milk antibody prevalence was 0.96. The correlation coefficient between prevalence measured by faecal egg count and both seroprevalence and milk antibody prevalence within the herd was 0.87. The diagnostic sensitivity and specificity for milk were 92% (95% CI=89-96) and 88% (95% CI=85-91), respectively, when the serum test was considered as a gold standard. In conclusion, the level of antibody to F. hepatica in milk is significantly correlated with the antibody level in serum and this ELISA is suitable as a means of routine veterinary diagnosis of exposure to F. hepatica in cattle and an alternative to testing sera. 相似文献
947.
Corn expressing an Escherichia coli-derived phytase gene: a proof-of-concept nutritional study in pigs 总被引:2,自引:0,他引:2
Two experiments were conducted to investigate the concept that the addition of corn expressing an Escherichia coli-derived gene (corn-based phytase; CBP) to a P-deficient diet would improve growth performance and P utilization in pigs. An E. coli-derived microbial phytase (expressed in Pichia pastoris) sprayed onto a wheat carrier (Quantum) was included for comparison. In Exp. 1, forty-eight 10-kg pigs were blocked by BW into 6 blocks and allotted to 8 dietary treatments such that the BW among dietary treatments was similar and given free access to feed for 28 d. The dietary treatments were a negative control (NC) with no inorganic P supplementation; NC + 2, 4, or 6 g of monosodium phosphate/kg; NC + 16,500, 33,000, or 49,500 phytase units (FTU) of CBP/kg; and NC + 16,500 FTU of Quantum/kg. In Exp. 2, twenty-four 13-kg barrows were assigned to the NC, NC + 16,500 or 33,000 FTU of CBP/kg, or NC + 16,500 FTU of Quantum/kg, in a nutrient- and energy-balance study consisting of 5 d of adjustment and 5-d collection periods. The total collection method was used to determine nutrient and energy balance. Addition of CBP to the low-P NC diet linearly increased (P < 0.01) ADG, G:F, and plasma P concentration of pigs during the 28-d study. There was no difference in ADG, G:F, or plasma P concentration between pigs fed the CBP or Quantum phytase at 16,500 FTU/kg. Weight gain, G:F, and plasma P concentration of pigs increased (P < 0.01) with monosodium phosphate supplementation, confirming P deficiency of the NC diet. Linear improvements (P < 0.05) in DM digestibility and energy retention were observed with CBP supplementation of the NC diet. Although there were linear (P < 0.01) and quadratic (P < 0.05) increases in N digestibility, N retention was unaffected by CBP supplementation of the NC diet in growing pigs. Phosphorus and Ca digestibilities and retentions improved linearly and quadratically (P < 0.01) with the addition of CBP to the NC diet. There was no difference in digestive utilization of P or Ca between pigs fed CBP and Quantum phytase at 16,500 FTU/kg. The data showed that the addition of a corn expressing an E. coli-derived gene to a P-deficient diet improved growth performance and indices of P utilization in pigs, and corn expressing phytase was as efficacious as Quantum phytase when supplemented in P-deficient diets for weanling pigs. 相似文献
948.
Marjorie J. Williams Brittany S. Baughman Andy Shores Ryan M. B. Gibson Michaela J. Beasley Timothy W. Morgan Matthew L. Williams 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(1):97-101
A 9-week-old puppy with refractory seizures and a dome-shaped head presented to the Mississippi State College of Veterinary Medicine Specialty Center for suspected hydrocephalus. Computerized tomography (CT) findings included transtentorial herniation and an intra-axial mass with dystrophic mineralization. Cerebrospinal fluid analysis revealed an increased nucleated cell count of 1100/μl (RI < 5/μl), erythrocyte count of 2.2 × 106/μl, and markedly increased microprotein of 1939 mg/dl (RI < 30 mg/dl). On cytologic examination of the CSF, numerous erythrophagocytic, and hemosiderin-laden macrophages were observed, which indicated chronic active hemorrhage. Many neutrophils, macrophages, and lymphocytes that contained numerous intracytoplasmic, pleomorphic, bright yellow crystals were observed. Considering the ongoing hemorrhage, the crystals were presumed to be hematoidin. A biopsy with histopathology was performed on the intra-axial mass, and the results were consistent with a vascular hamartoma. We speculate that the formation of these crystals was related to the ongoing hemorrhage associated with the vascular hamartoma. Identification of these crystals may be useful to aid in the identification of chronic hemorrhage associated with vascular malformations or lesions within the central nervous system. 相似文献
949.
Preliminary Investigation of the Treatment of Equine Medial Femoral Condylar Subchondral Cystic Lesions With a Transcondylar Screw 下载免费PDF全文
950.