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Not all economically disadvantaged—“less developed” or “lagging”—regions are the same. They are, however, often bundled together for the purposes of innovation policy design and implementation. This paper attempts to determine whether such bundling is warranted by conducting a regional level investigation for Canada, the United States, on the one hand, and Europe, on the other, to (a) identify the structural and socioeconomic factors that drive patenting in the less developed regions of North America and Europe, respectively; and (b) explore how these factors differ between the two contexts. The empirical analysis, estimated using a mixed‐model approach, reveals that, while there are similarities between the drivers of innovation in North America's and Europe's lagging regions, a number of important differences between the two continents prevail. The analysis also indicates that the territorial processes of innovation in North America's and Europe's less developed regions are more similar to those of their more developed counterparts than to one another.  相似文献   
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This study examines factors affecting the rate and extent of biomass build-up among commercially important groupers, snappers, grunts, parrotfish and surgeonfish in a network of four marine reserves in southwest St. Lucia, Caribbean. Reserves constituted 35% of the total reef area originally available for fishing. Protection was instigated in 1995 after a baseline survey with annual or biennial censuses performed until 2002. Each survey consisted of 114 fifteen minute fish counts in reserves and 83 in fishing grounds, at depths of 5 m and 15 m in a 10 m diameter counting area. Estimates of number and size (cm) of target species were used to calculate fish family biomass. Data were analysed using three-way ANOVA in a before-after-control-impact pairs (BACIP) design. All families increased significantly in biomass over time at nearly all sites. Increases were greater in reserves than fishing grounds, except for grunts, and responses were strongest in parrotfish and surgeonfish. The combined biomass of families more than quadrupled in reserves and tripled in fishing grounds between 1995 and 2002. During this period coral cover declined by 46% in reserves and 35% in fishing grounds. Multiple regression showed that neither habitat characteristics nor habitat deterioration significantly affected rates of biomass build-up. The key factor was protection from fishing, which explained 44% of the variance in biomass growth. A further 28% of the variance was explained by sedimentation, a process known to stress reef invertebrates, significantly reducing the rate of biomass build-up. St. Lucia’s reserves succeeded in producing significant gains to fish stocks despite coral cover and structural complexity falling steeply over the period of the study.  相似文献   
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Objective To determine the long‐term efficacy, complications, and duration of effect of a cyclosporine (CsA) suprachoroidal implant (CSI) in horses with equine recurrent uveitis (ERU). Methods Horses with ERU were treated with a 6‐mm diameter, 25 mg, reservoir matrix CsA implant in the deep sclera adjacent to the suprachoroidal space. Horses with follow‐up >1 year were examined for frequency of uveitis episodes, complications, and vision at last recheck. Results Data from 151 eyes of 133 horses from the USA and Europe that had CsA devices implanted for ERU were reviewed. Follow‐up time ranged from 13 to 85 months after surgery, with a mean and median follow‐up time of 28.9 and 26.3 months, respectively. Overall, at last follow‐up 78.8% of eyes were considered visual and the overall mean frequency of uveitis episodes after CSI was 0.09 ± SD 0.08 episodes per month. The most common complications leading to vision loss at last follow‐up were persistent uveitis episodes (54%), glaucoma (22%), mature cataracts (16%), and retinal detachment (6%). Persistent uveitis episodes tended to be the highest cause of vision loss in horses with <24 months and >48 months of follow‐up. Conclusions This study demonstrated the long‐term maintenance of vision of horses with ERU implanted with a CSI. The increased vision loss related to uveitis episode of inflammation in eyes after the likely depletion of CsA from the CSI suggests that a repeat CSI may be required at or before 48 months after surgery.  相似文献   
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Bottom trawling (nets towed along the seabed) spread around the British Isles from the 1820s, yet the collection of national fisheries statistics did not begin until 1886. Consequently, analysis of the impacts of trawling on fish stocks and habitats during this early period is difficult, yet without this information, we risk underestimating the extent of changes that have occurred as a result of trawling activities. We examined witness testimonies recorded during two Royal Commissions of Enquiry (1863–66 and 1883–85). These enquiries interviewed hundreds of fishers about the early effects of sail trawling and the changes they were witnessing to fish stocks, habitats and fishing practises during this time. We converted all quantitative statements of perceived change in fish stocks and fishing practices to relative change. Witnesses from the north‐east of England interviewed during 1863 revealed an average perceived decline in whitefish of 64% during their careers, which many blamed upon trawling. Between 1867 and 1892, trawl‐landing records from the same location suggest that this trajectory continued, with fish availability declining by 66% during the period. Fishers adapted to these declines by increasing distances travelled to fishing grounds and increasing gear size and quantity. However, inshore declines continued and by the early 1880s even trawl owners were calling for closures of territorial waters to trawling in order to protect fish nursery and spawning grounds. Until now, these testimonies have been largely forgotten, yet they reveal that alterations to near‐shore habitats as a result of trawling began long before official data collection was initiated.  相似文献   
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The article presents a material-geographic study of contemporary log home manufacturing in the Eastern Woodlands of North America. The study investigated relationships between log conversion (i.e., processing) methods and regional location. Manufacturers were grouped by their conversion methods, using hierarchical cluster analysis; and analyzed for spatial correlation, using standard deviational ellipses (SDEs). Tree species utilization, log treatment, horizontal surface type, and corner notch type were found to be spatially differentiating. These attributes were tested for their ability to predict manufacturers’ culture region using multinomial logistic regression (MLR) models. Tree species utilization was an independent variable in all of the predictive models, suggesting a correspondence between building culture and ecological regions. This is consistent with earlier research. The findings suggest that location drives tree species utilization and, thereby, building methods. Like the eco-region itself, log conversion methods vary on a north-south gradient. It is argued that construction knowledge is geo-contextual and that the replacement of scientific wood extraction with ecosystem management as the central paradigm in forestry calls for geo-contextual approaches to sustainability in the construction industry.  相似文献   
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Analysis of published CD5 amino acid sequences identified conserved sequences with potentially immunogenic epitopes. To obtain anti-porcine CD5, synthetic peptides representing conserved sequences identified in mouse, human, cattle and sheep CD5 cytoplasmic tail domains were linked to KLH and used to immunize rabbits. Anti-synthetic peptide serum reacted with an antigen extracted from porcine lymphocyte membrane which was consistent in size (67 kDa) with CD5. Murine monoclonal anti-porcine wCD5 (b53b7) and the anti-CD5 synthetic peptide serum react with the same ligand confirming that porcine wCD5 has conserved amino acid sequences similar to those of CD5 of several species. Analysis of porcine genome for CD5 gene sequences by PCR was conducted to verify the presence of CD5-like genes. Oligomeric primers were designed to identify CD5-like sequences by polymerase chain reaction in pigs and other species. Amplified DNA similar in size to that predicted for CD5 elements were amplified from a variety of animal genomes including that of pig. The porcine-derived fragment was cloned and shown to be 96% similar to mouse CD5. The use of published CD sequences for prediction of immunogenic peptides has provided a complimentary alternative to the more traditional approaches to production of CD-specific antibodies.  相似文献   
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Although both topical and systemic anti-inflammatory agents have a place in veterinary ophthalmology, they play only a small role in overall patient management. They must be used appropriately to prevent ocular damage and loss of vision from inflammation and are not a replacement for a complete ophthalmic examination and specific treatment directed at the etiology of the problem. If used indiscriminately, they can result in local or systemic side effects or toxicities, many of which are worse than the initial problem for which they were selected. Just as topical corticosteroids are contraindicated with infectious keratitis, so are systemic corticosteroids contraindicated in patients with ocular inflammation resulting from a systemic infectious process. Anti-inflammatories must be used at the appropriate dosage and frequency. Use of corticosteroids that have low intraocular penetration for intraocular disease or corticosteroids with low potency is a waste of time and money. The most expensive medication is one that does not work. Avoid combination therapies when only a single medication is required. These do not save time or money and have the potential to result in the development of drug-related diseases. Diseases for which anti-inflammatory therapy has little or no indication include corneal scars, corneal edema, corneal pigmentation, corneal dystrophy, cataracts without inflammation, glaucoma, and retinal atrophy and degeneration. Last, remember that all commercially available ophthalmic medications are specifically formulated for use in the eye. Their pH, concentration, osmolality, and melting temperature all are designed to facilitate penetration. The use of dermal and otic preparations to treat ophthalmic problems is contraindicated.  相似文献   
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