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排序方式: 共有159条查询结果,搜索用时 46 毫秒
101.
Kamstock DA Ehrhart EJ Getzy DM Bacon NJ Rassnick KM Moroff SD Liu SM Straw RC McKnight CA Amorim RL Bienzle D Cassali GD Cullen JM Dennis MM Esplin DG Foster RA Goldschmidt MH Gruber AD Hellmén E Howerth EW Labelle P Lenz SD Lipscomb TP Locke E McGill LD Miller MA Mouser PJ O'Toole D Pool RR Powers BE Ramos-Vara JA Roccabianca P Ross AD Sailasuta A Sarli G Scase TJ Schulman FY Shoieb AM Singh K Sledge D Smedley RC Smith KC Spangler WL Steficek B Stromberg PC Valli VE Yager J 《Veterinary pathology》2011,48(1):19-31
Neoplastic diseases are typically diagnosed by biopsy and histopathological evaluation. The pathology report is key in determining prognosis, therapeutic decisions, and overall case management and therefore requires diagnostic accuracy, completeness, and clarity. Successful management relies on collaboration between clinical veterinarians, oncologists, and pathologists. To date there has been no standardized approach or guideline for the submission, trimming, margin evaluation, or reporting of neoplastic biopsy specimens in veterinary medicine. To address this issue, a committee consisting of veterinary pathologists and oncologists was established under the auspices of the American College of Veterinary Pathologists Oncology Committee. These consensus guidelines were subsequently reviewed and endorsed by a large international group of veterinary pathologists. These recommended guidelines are not mandated but rather exist to help clinicians and veterinary pathologists optimally handle neoplastic biopsy samples. Many of these guidelines represent the collective experience of the committee members and consensus group when assessing neoplastic lesions from veterinary patients but have not met the rigors of definitive scientific study and investigation. These questions of technique, analysis, and evaluation should be put through formal scrutiny in rigorous clinical studies in the near future so that more definitive guidelines can be derived. 相似文献
102.
Scase TJ Edwards D Miller J Henley W Smith K Blunden A Murphy S 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(1):151-158
The Patnaik histologic grading system is commonly used to predict the behavior of cutaneous mast cell tumors (MCTs) in dogs, but it is less useful for grade 2 MCTs because they exhibit considerable variation in biological behavior. In this retrospective study, immunohistochemical staining for Ki-67, proliferating cell nuclear antigen (PCNA), and survivin and a standardized argyrophilic staining of nucleolar organizer regions (AgNOR) protocol were performed on 121 archived paraffin-embedded specimens of canine cutaneous MCTs, for which clinical follow-up data were available. Cox regression models indicated that the Ki-67 score (hazard ratio, 1.92; P < .001) and mean AgNOR score (hazard ratio, 2.57; P < .001) were significantly associated with Patnaik grade and survival time. A binary Ki-67 variable (cutoff point Ki-67 score = 1.8) was a significant predictor of survival for dogs with grade 2 MCTs. The estimated 1-, 2-, and 3-year survival probabilities for dogs with grade 2 MCTs and Ki-67 scores less than 1.8 were 0.92, 0.86, and 0.77, respectively (SEs, 0.08, 0.14, and 0.23, respectively; median not estimable). The corresponding survival probabilities for dogs with grade 2 MCTs and Ki-67 scores higher than 1.8 were 0.43, 0.21, and 0.21, respectively (SEs, 0.19, 0.18, and 0.18, respectively; median survival time, 395 days). No significant association was identified between survival and survivin score or PCNA score. This study shows that both mean AgNOR score and Ki-67 score are prognostic markers for canine MCTs. The Ki-67 score can be used to divide Patnaik grade 2 MCTs into 2 groups with markedly different expected survival times. 相似文献
103.
Fifteen fuzzless seed lines in “obsolete” backgrounds of Upland cotton (Gossypium hirsutum L.) were obtained from the National Cotton Germplasm Collection and evaluated for fuzzless seed genotype, lint percent, and lint quality. Fourteen of these fifteen lines were found to be homozygous for the dominant fuzzless seed allele N 1. Only one line was homozygous for the recessive fuzzless seed allele n 2. The measured lint percent of each line was very stable through time, however, large variability existed between many of the N 1 lines ranging from 0.7 to 23.6% lint. The lint percent for the n 2 line was 24.4%. Scanning electron microscopy was used to differentiate patterns of lint initiation on 1 day post anthesis ovules. General patterns included: first, lint initiation restricted to the chalazal end of the seed crest; second, lint initiation along the seed crest and laterally around the chalazal end of the ovule; and third, lint initiation covered all but the micropylar end of the ovule. Lint quality was evaluated for each line using the Advanced Fiber Information System (AFIS) which included measurements of length, maturity, and fineness. The means of each measurement varied among the fuzzless seed lines with significant differences between fiber length, short fiber content, immature fiber content, fineness, and maturity ratio. No correlation was found between lint percent and any of the lint quality measurements. These lines will provide a valuable resource for the study of fiber initiation and lint quality. 相似文献
104.
Composts of municipal solid waste in a commercial scale facility were assayed for enzymatic activities over time. The main enzymes assayed in this study were alkaline phosphatase, acid phosphatase, endo-cellulase, glucosidase, and lipase (C10). The biomass was measured by using lipid phosphate as a measure of the amount of cellular membranes, and metabolism was measured by the amount of 14C-acetate incorporated into the lipid phosphate pool. All tests followed steady trends which show promise for use as possible stability and maturity indicators. Cellulase activity appears to be a good indicator of stability. The lipase activity appears to be a good indicator of compost maturity. A simple test strip (Api-Zyme from Api Analytab Products, Plainview, New York) was also used and compared to the standard enzyme assay methods. Api-Zyme and standard methods gave comparable results. The use of specific enzymatic activities presents an inexpensive and fast method, which may be combined with others, to predict a composts' stability and possible maturity status based on microbial activity. 相似文献
105.
Antioxidative activities of oolong tea 总被引:5,自引:0,他引:5
Zhu QY Hackman RM Ensunsa JL Holt RR Keen CL 《Journal of agricultural and food chemistry》2002,50(23):6929-6934
While the antioxidative properties of green and black tea have been extensively studied, less attention has been given to these properties in oolong tea. The reducing powers, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities, the amount of total phenolic compounds, the inhibitory effect on FeCl(2)/H(2)O(2) (Fenton reaction system)-induced DNA damage, and the inhibitory effect on erythrocyte hemolysis of an oolong tea water extract (OTE) were evaluated in the present study. The OTE was found to have strong antioxidative activities in all of the model systems tested. When the OTE was separated into different fractions according to molecular weight, it was found that the fractions with higher amounts of phenolic compounds (lower molecular weight) have stronger antioxidative activities. The present results support the concept that oolong tea contains several low molecular weight antioxidants that may have health promotion activities. 相似文献
106.
A method is described to separate and quantitate free amino acids from soil solutions extracted rapidly by centrifugation at 10,000 g for 5 min. Centrifugation of soil samples with forces up to 20,000 g did not affect the content of ammonium and water soluble organic carbon in solution, therefore it was concluded that the integrity of microbial cells was unaffected.The method of amino acid analysis involved treatment of the soil solution with tritiated 1-Fluoro-2,4-dinitrobenzene under alkaline conditions after addition of a known concentration of a standard mixture of amino acids. After extraction, the dinitrophenyl (DNP)-amino acids were separated by two-dimensional thin layer chromatography. Quantification was effected by counting the 3H-activity of each spot and comparing it to that of spots of a standard amino acid mixture of known concentration. The method has been tested and found satisfactory on a variety of cultivated soils, except for an Andept soil with a high content of metallic ions in solution.The total free amino acid content in cultivated and virgin soil samples ranged between 0.32 and 4.72 μg g?1 soil.Alanine, phenylalanine and threonine were the most abundant followed by valine and the aspartic-glutamic acid complex. Basic amino acids, those containing S (methionine and cystine), and the isoleucine-leucine pair were the least abundant and frequently not detected. With the Chernozemic order the total amino acid content decreased in the following order: Brown > Dark Brown > Black. Virgin soil samples contained more but not always a wider range of free amino acids than did cultivated soils. A Luvisolic soil cropped for 50 yr to a 5-yr rotation contained fewer and a narrower range of free amino acids than did the same soil cropped to a wheat-fallow rotation. 相似文献
107.
Jennifer L. Stoffel Stith T. Gower Jodi A. Forrester David J. Mladenoff 《Forest Ecology and Management》2010
Soil surface CO2 flux (Sflux) is the second largest terrestrial ecosystem carbon flux, and may be affected by forest harvest. The effects of clearcutting on Sflux have been studied, but little is known about the effect of alternative harvesting methods such as selective tree harvest on Sflux. We measured Sflux before and after (i) the creation of forest canopy gaps (simulating group tree selection harvests) and (ii) mechanized winter harvest but no tree removal (simulating ground disturbance associated with logging). The experiment was carried out in a sugar maple dominated forest in the Flambeau River State Forest, Wisconsin. Pre-treatment measurements of soil moisture, temperature and Sflux were measured throughout the growing season of 2006. In January–February 2007, a harvester created the canopy gaps (200–380 m2). The mechanization treatment consisted of the harvester traveling through the plots for a similar amount of time as the gap plots, but no trees were cut. Soil moisture and temperature and Sflux were measured throughout the growing season for 1 year prior to harvest and for 2 years after harvest. Soil moisture and temperature were significantly greater in the gap than mechanized and control treatments. Instantaneous Sflux was positively correlated to soil moisture and soil temperature at 2 and 10 cm, but temperature at 10 cm was the single best predictor. Annual Sflux was not significantly different among treatments prior to winter 2007 harvest, and was not significantly different among treatments after harvest. Annual (+1 std. err.) Sflux averaged 967 + 72, 1011 + 72, and 1012 + 72 g C m−2 year−1 in the control, mechanized and gap treatments, respectively, for the 2-year post-treatment period. The results from this study suggest selective group tree harvest significantly increases soil moisture and temperature but does not significantly influence Sflux. 相似文献
108.
David W. McGill Shawn T. Grushecky Stuart Moss Chad Pierskalla Al Schuler 《Small-Scale Forestry》2008,7(2):105-116
As global competition increases for wood-based products, the need for more efficient supply chains becomes increasingly important.
In the forest products sector, these supply chains involve individuals and firms ranging from private forestland owners with
standing timber to factories producing final finished products. Long-term timber leases are one mechanism that can be used
to develop access to timber supplies for companies unable or unwilling to purchase land outright for growing timber. To investigate
private forest owner opinions and attitudes regarding long-term timber leases, we conducted a survey of landowners from Wetzel
county, West Virginia. No long-term leases were reported by respondents, but 24% claimed they would enter a lease under certain
conditions. The most frequently listed concern related to long-term timber leases was for the “loss of control”. Results of
this survey are discussed in the light of forest management efforts that might be used to improve the social, financial, and
environmental benefits for private forest owners. 相似文献
109.
Michael A. Nannini Jodi Goodrich John M. Dettmers Daniel A Soluk David H. Wahl 《Ecology of Freshwater Fish》2012,21(4):499-509
The spatial and temporal complexity of large river ecosystems likely promotes biological diversity within riverine larval fish assemblages. However, the focus of most previous riverine studies of larval fish distribution has tended to concentrate mainly on backwater habitats. There has been less focus on the value of the main channel for larval fishes. We sampled two habitats types (three main channel sites and three backwater lakes) along 20 km of the Illinois River ecosystem during 2 years to compare the larval fish distribution along both spatial and environmental gradients between these habitats. Across the 2 years of this study, we found similar trends in the spatial and temporal distribution of larval fish, although there were some differences in densities between years. The relative abundance and size of many of the different fish taxa varied among habitats. Centrarchids, clupeids, poeciliids, cyprinids (excluding common carp) and atherinids were more abundant within backwater lake habitat. In contrast, common carp (Cyprinus carpio), sciaenids, moronids and catostomids were more abundant in main channel habitats. Furthermore, sciaenid and clupeid larvae captured in the backwater lake habitat were larger as the season progressed than those captured in the main channel. Our study suggests that larval fish show habitat specialisation, similar to adults, indicating that both the backwater lakes and the main channel are both important for larval fish and preserving the diversity of the fish assemblages in large floodplain rivers. 相似文献