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排序方式: 共有137条查询结果,搜索用时 31 毫秒
91.
Azim Saiful Rasmussen Jesper Nielsen Jon Gislum René Laursen Morten Stigaard Christensen Svend 《Precision Agriculture》2019,20(6):1199-1210
Precision Agriculture - The global spatial accuracy of ortho-mosaics based on images from consumer-grade unmanned aerial vehicles (UAVs) is relatively low. The use of ground control points (GCPs)... 相似文献
92.
Boysen L Sørensen P Larsen M Serup J Kristensen F 《American journal of veterinary research》2002,63(4):565-569
OBJECTIVE: To investigate whether the degree of erythema during an induced erythematous reaction, the histamine skin test reaction, can be assessed objectively by use of chromametry and image analysis of digital photographs. ANIMALS: 9 pet dogs (6 Golden Retrievers and 3 yellow Labrador Retrievers). PROCEDURE: Histamine phosphate was injected intradermally, and erythema of the wheal reaction was evaluated during the hour that followed. This was done by use of clinical scores, chromametry, and image analysis of digital photographs. Method reproducibility was tested for visual evaluation of printouts of digital photographs and for image analysis of the same photographs. RESULTS: The coefficient of variation of the technically derived erythema values was < 10%. The reproducibility of image analysis was high and the range of agreement between observers narrow. Using chromametry, it was not possible to differentiate between various degrees of erythema intensity as visually perceived. In contrast, use of image analysis of digital photographs enabled discrimination of slight erythema from moderate and marked erythema. The dynamics of reaction measured by chromametry followed the clinical observation. CONCLUSIONS AND CLINICAL RELEVANCE: Chromametric values are comparable to those obtained by visual inspection. As the result of standardized conditions, chromametry is preferred over digital photography. 相似文献
93.
Simon Chioma Weli Malachy Ifeanyi Okeke Morten Tryland ?ivind Nilssen Terje Traavik 《Canadian journal of veterinary research》2004,68(2):140-145
Avipoxviruses from different geographic regions of the world have been characterized to study their genetic and biological properties, but so far, no such work has been performed on Norwegian isolates. Lesions suggestive of avian pox, found on a Norwegian wild sparrow (Passer domesticus) and wood pigeon (Palumbus palumbus), were obtained in 1972 and 1996, respectively. Histologically, these lesions were demonstrated to be characteristic of poxvirus infections and the poxvirus was observed using an electron microscope. The resulting viruses were propagated in chicken embryo fibroblast cells. Restriction fragment length polymorphism of genomes from 2 Norwegian isolates and fowl pox vaccine strain, generated by BamHI, revealed a high degree of heterogeneity among the isolates. The profiles of avipoxviruses isolated from wild birds were clearly distinct from each other and also to the fowl poxvirus strain. Furthermore, chickens experimentally infected with pigeon poxvirus had higher antibody titers and extensive lesions compared to other isolates. This may suggest that pigeon poxvirus is more virulent than the other isolates. 相似文献
94.
Three pigs were given intravenous injections of disintegrated cells of Salmonella cholerae-suis. One of these pigs developed macroscopic bilateral renal cortical necrosis. Histologic examination revealed, besides total cortical parenchymal necrosis, also severe vascular injury, characterized with fibrinoid necrosis of the vessel walls and fibrin thrombi within their lumina. These findings were interpreted as a result of a generalized Shwartzman reaction, provoked by the action of bacterial endotoxin. 相似文献
95.
In this paper, a statistical framework based upon shift-share analysis is employed to analyse regional differences in Norway
regarding changes in harvesting levels and number of full-time equivalent employees in wood processing. Changes in harvesting
levels and employment differ between regions. A tendency found is that there has been a moderate centralisation in the period
1990–2000 with respect to harvesting levels. The analysis indicates that remote municipalities harvest relatively more in
periods with a high harvesting intensity, while the harvesting level is more evenly distributed among the regions in other
periods. There is, however, no clear picture whether there has been a centralisation or decentralisation regarding woodbased
employment. Differences between regions may therefore be explained by structural factors, for example the degree to which
firms in a particular region concentrate on production of bulky commodities or more customeroriented niche production. 相似文献
96.
Marit Espe Bjørn Liaset Ernst Morten Hevrøy Adel El‐Mowafi 《Aquaculture Research》2011,42(8):1123-1130
In the current study, we tested whether the addition of a small amount of crystalline dl ‐methionine to a fishmeal‐based diet would affect general sulphur metabolism and apparent digestibility in Atlantic salmon (Salmo salar). Triplicate tanks of salmon with mean BW of half a kilo were fed a control diet or the control diet supplemented with 0.2 wt%dl ‐methionine (+17% methionine relative to control diet) for a period of 3 months. Feed intake and thus nutrient intake did not differ significantly between treatments. Fish fed the diet supplemented with dl ‐methionine had 18% higher mean intake of methionine. The apparent energy digestibility was significantly improved in the salmon fed the methionine‐enriched diet as was the methionine digestibility. Salmon fed the methionine‐supplemented diet had about 32% higher plasma‐free methionine concentration and 25% more total homocysteine 5 h post prandial. No difference was observed in hepatic‐free methionine, but hepatic cystathionine (~62%) and taurine (~20%) were significantly higher in fish fed the methionine‐enriched diet due to a higher transsulphuration. In the liver, taurine might be conjugated to bile acids (BAs), and conjugation of BAs increases their solubility and enhances their biliary secretion affecting the digestibility. Both faecal and plasma BA concentrations were elevated in fish fed the methionine‐enriched diet, although the differences did not reach statistical significance. Taken together, our data show that feeding salmon a fishmeal‐based diet supplemented with a small amount of crystalline dl ‐methionine increased the apparent energy digestibility, possibly through an increased liver transsulphuration and taurine production, which might enhance BA conjugation and biliary secretion. 相似文献
97.
James Cock Thomas Gitterle Marcela Salazar Morten Rye 《Aquaculture (Amsterdam, Netherlands)》2009,286(1-2):1-11
Diseases are a major constraint on the intensive production of shrimps. Conditions in production ponds favour disease development, and epidemics of several previously unreported diseases have occurred and caused severe losses. When elimination, eradication or cultural control is difficult, selective breeding for host resistance to the pathogen may be an attractive option for disease control. However, host resistance is not a panacea and should only be considered when (a) the disease causes severe damage (b) there are no other existing simple cost effective control measures and (c) there is demonstrable genetic variation in resistance and this is not coupled with an excessive level of negative associations with other desirable characteristics. Shrimp have only recently been domesticated and breeding for resistance only began in the mid 1990s; there is limited experience with shrimp breeding in particular and crustaceans in general. Consequently, the principles and concepts behind breeding programmes are based largely on experiences with other species in both the plant and animal kingdoms. Commercial growers now seed ponds with shrimp populations selected for resistance to Taura Syndrome Virus with excellent results, whilst up to now development of White Spot Syndrome Virus resistant populations has been an elusive goal. The original TSV resistant populations were developed using simple mass selection techniques (Colombia). In later generations family based selection has been applied on populations, which initially had survival rates of about 30%, with care taken to reduce inbreeding and loss of genetic variation. This suggests that when the original populations have a reasonable level of resistance, and straightforward, effective selection protocols exist, it is relatively simple to breed for resistance. With catastrophic diseases, such as WSSV, which cause mortalities of 98% or more the frequency of resistance is low and it is suggested that for theoretical reasons single gene, rather than polygenic, resistance is likely to develop. The low frequency of resistance genes in breeding populations may cause genetic bottlenecks which will greatly reduce the genetic variation in the populations. In order to maintain the genetic variation the genes from the small numbers of survivors should be introgressed into populations with broader genetic variability. Furthermore, in order to minimize the probability of breakdown of resistance pyramiding of resistant genes on different loci would be advantageous.Genetic variation in resistance may be encountered either in the initial base populations or may spontaneously arise due to mutations or new recombinants. With extremely prolific species such as shrimps, millions of animals can readily be screened for survival and hence resistant mutants or recombinants may be identified. Once genetic variation has been detected the most appropriate breeding methodology will depend on the nature of both the resistance and the disease or diseases that are of interest to the producers. 相似文献
98.
Identification of novel secaloindoline-a and secaloindoline-b alleles in CIMMYT hexaploid triticale lines 总被引:4,自引:1,他引:4
Genying Li Zhonghu He Roberto Javier Pea Xianchun Xia Morten Lillemo Qixin Sun 《Journal of Cereal Science》2006,43(3):378-386
To characterize kernel hardness, an important trait in triticale breeding, and to identify secaloindoline alleles present in hexaploid triticale lines developed at International Maize and Wheat Improvement Center (CIMMYT) a total of 171 secondary hexaploid lines were analyzed for grain hardness using the Single Kernel Characterization System. They showed a large spectrum of kernel hardness types, from very soft to very hard, with values ranging from 8.6 to 84.9. The occurrence of starch granule-associated friabilin was studied in 30 lines, including 10 hard, 9 mixed and 11 soft genotypes. All soft lines displayed a high level of friabilin, whereas the hard lines showed almost no friabilin, indicating that friabilin is directly involved in the formation of grain texture in secondary hexaploid triticales. Two novel secaloindoline alleles were identified and designated as Sina-R1b and Sinb-R1c. Compared with SINAa, the deduced amino acid sequence of SINAb showed a Trp to Arg substitution at position 44. SINBc had a Gly to Ser substitution at position 78 and a Gly to Arg substitution at position 115, as well as a Cys insertion in the signal peptide, in comparison to SINBa. The novel alleles Sina-R1b and Sinb-R1c were detected in both the soft and hard triticale lines. 相似文献
99.
100.
Tryland M Thoresen SI Kovacs KM Lydersen C 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):199-203
BACKGROUND: Abnormal physiological conditions and diseases can change the concentrations of enzymes, metabolites, and minerals in the body. Serum chemistry information may thus be indicative of a specific disease; interpretation of such information requires knowledge of serum chemistry reference intervals from a seemingly healthy population of the species. OBJECTIVE: The aim of this study was to obtain serum chemistry reference intervals for a population of white whales. METHODS: Blood samples were collected from 21 free-ranging white whales (beluga; Delphinapterus leucas). The whales were live-captured in nets during 1996-2001 in Storfjorden, Van Mijenfjorden, and Van Keulenfjorden (Svalbard, Norway). While the whales were briefly physically restrained, blood was collected from the caudal vein into vacuum tubes without anticoagulant. The blood was left to clot for 4-6 hours before serum was obtained by centrifugation. The serum samples were then kept at -20 degrees C until analysis. Enzymes (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase [ALP], creatine kinase, lactate dehydrogenase [LDH], amylase, lipase), metabolites (urea, creatinine, bilirubin, cholesterol, triglycerides, nonesterified fatty acids, glucose), and minerals (calcium, phosphate, magnesium, sodium, potassium, chloride) were analyzed in an Advia 1650 System (Bayer, Tarrytown, NY, USA). Cortisol was analyzed in an Immulite One system (Diagnostic Products Corporation, Los Angeles, CA, USA). The major blood proteins (albumin and globulins) were separated by gel electrophoresis in a Beckman Paragon electrophoresis system (Beckman Coulter, Inc., Fullerton, CA, USA). RESULTS: Serum values for all analytes were reported as median and range, and reference intervals were calculated as 10-90th percentiles. Activities of ALP and LDH and cortisol concentration were higher, and protein and bilirubin concentrations were lower compared with those previously reported for white whales from Canada; remaining results were strikingly similar in these 2 white whale populations. CONCLUSIONS: These data provide valuable serum chemistry reference intervals for future health assessments of white whales in Svalbard and other white whale populations, as well as captive individuals. 相似文献