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951.
BRYDEN J. STANLEY BVMS MVetSc Diplomate ACVS JOE G. HAUPTMAN DVM MS Diplomate ACVS MICHELE C. FRITZ BSc LVT DIANA S. ROSENSTEIN DVM MS Diplomate ACVR 《Veterinary surgery : VS》2010,39(2):139-149
Objectives— To compare esophageal function in dogs with idiopathic laryngeal paralysis (ILP) to age and breed matched controls; to determine if dysfunction is associated with aspiration pneumonia over 1 year; and to compare clinical neurologic examination of dogs with ILP at enrollment and at 1 year. Study Design— Prospective controlled cohort study. Animals— Dogs with ILP (n=32) and 34 age and breed matched healthy dogs. Methods— Mean esophageal score was determined for each phase of 3 phase esophagrams, analyzed blindly. After unilateral cricoarytenoid laryngoplasty, dogs with ILP were reexamined (including thoracic radiography) at 1, 3, 6, and 12 months. Neurologic status was recorded at enrollment, 6 and 12 months. Results— Esophagram scores in dogs with ILP were significantly higher in each phase compared with controls, most notably with liquid (P<.0001). Dysfunction was more pronounced in the cervical and cranial thoracic esophagus. Five dogs that had aspiration pneumonia during the study had significantly higher esophagram scores than dogs that did not develop aspiration pneumonia (P<.02). Ten (31%) ILP dogs had generalized neurologic signs on enrollment and all ILP dogs developed neurologic signs by 1 year (P<.0001). Conclusions— Dogs with ILP also have esophageal dysfunction. Postoperative aspiration pneumonia is more likely in dogs with higher esophagram scores. Dogs with ILP will most likely develop generalized neuropathy over the course of 1 year. Clinical Relevance— Esophagrams and neurologic examinations should be performed on all dogs with ILP. 相似文献
952.
KEVIN K. AU BSc BVMS WANDA J. GORDON‐EVANS DVM PhD Diplomate ACVS DIANNE DUNNING DVM MS Diplomate ACVS KRISTEN J. O'DELL‐ANDERSON DVM MS Diplomate ACVR KIM E. KNAP BS CVT CCRP DOMINIQUE GRIFFON DVM PhD Diplomate ACVS & ECVS ANN L. JOHNSON DVM MS Diplomate ACVS 《Veterinary surgery : VS》2010,39(2):173-180
Objectives— To compare short‐ and long‐term functional and radiographic outcome of cranial cruciate ligament (CrCL) injury in dogs treated with postoperative physical rehabilitation and either tibial plateau leveling osteotomy (TPLO) or lateral fabellar suture stabilization (LFS). Study Design— Prospective observational clinical study. Animals— Medium to large breed dogs with naturally occurring CrCL injury (n=65). Methods— Dogs with CrCL injury were treated with either TPLO or LFS and with identical physical rehabilitation regimes postoperatively. Limb peak vertical force (PVF) was measured preoperatively and at 3, 5, and 7 weeks, and 6 months and 24 months postoperatively. Stifles were radiographically assessed for osteoarthrosis (OA) preoperatively and 24 months postoperatively. Results— Thirty‐five dogs had LFS and 30 dogs had TPLO. Radiographic OA scores were significantly increased at 24 months compared with preoperative scores in all dogs. Radiographic OA scores preoperatively and at 24 months were not significantly different between treatment groups. PVF was significantly increased from preoperative to 24 months among both treatment groups but not significantly different between treatment groups preoperatively or at 3, 5, 7 weeks, 6, or 24 months. Conclusion— No significant difference in outcome as determined by ground reaction forces or radiographic OA scores were found between dogs with CrCL injury treated with LFS or TPLO. Clinical Relevance— LFS and TPLO remain good options for stabilizing stifles with CrCL injury with all dogs showing significant functional improvement. This study does not support the superiority of either surgical technique. 相似文献
953.
954.
Prioritizing localized management actions for seagrass conservation and restoration using a species distribution model
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Matthew P. Adams Megan I. Saunders Paul S. Maxwell Daniel Tuazon Chris M. Roelfsema David P. Callaghan Javier Leon Alistair R. Grinham Katherine R. O'Brien 《水产资源保护:海洋与淡水生态系统》2016,26(4):639-659
955.
For yield based site-specific management to be successful in fields with crop rotations, changes in management zones between
crops must be determined. The study objectives were to determine if yield classes change between crops within a rotation and
whether soil properties can predict the yield classes or the year-to-year changes. A percentile classification method was
used to categorize yearly soybean (Glycine max) and rice (Oryza sativa) yield in two fields with soybean-rice-soybean rotations into low, medium and high yield classes. There was little agreement
in yield classifications between years. Yield class based on soil properties was predicted accurately by linear discriminant
analysis in Field 1 20–67% of the time and in Field 2 13–83% of the time. Predictions in Field 1 were based on soil available
Mg and P, elevation and the deep soil apparent electrical conductivity (ECa). Predictions in Field 2 were based on soil texture, soil available P, K and Mg, and pH. The linear discriminant analysis
was also able to predict year-to-year changes in yield class. Changes in class in Field 1 could be predicted by total soil
C and N, silt, and soil available Mg and P depending on the year. Soil texture, soil available P, K and Mg, total soil C and
pH, elevation and deep soil ECa predicted yield changes in Field 2 depending on the year. The results of this study indicate only limited success at management
zone definition in a soybean-rice rotation. Further investigation is needed with other crop rotation sequences to verify the
findings of this study. 相似文献
956.
Gary A. Sod DVM PhD Laura M. Riggs DVM PhD Diplomate ACVS Colin F. Mitchell BVMS MS Diplomate ACVS George S. Martin DVM MS MBA Diplomate ACVS Marjorie S. Gill DVM MS Diplomate ABVP 《Veterinary surgery : VS》2010,39(5):581-587
Objectives: To compare the monotonic biomechanical properties and fatigue life of a 5.5‐mm‐broad locking compression plate (5.5 LCP) fixation with a 4.5‐mm‐broad locking compression plate (4.5 LCP) fixation to repair osteotomized equine 3rd metacarpal (MC3) bones. Study Design: In vitro biomechanical testing of paired cadaveric equine MC3 with a middiaphyseal osteotomy, stabilized by 1 of 2 methods for fracture fixation. Animal Population: Fifteen pairs of adult equine cadaveric MC3 bones. Methods: Fifteen pairs of equine MC3 were divided into 3 test groups (5 pairs each) for (1) 4‐point bending single cycle to failure testing, (2) 4‐point bending cyclic fatigue testing, and (3) torsional single cycle to failure testing. An 8‐hole, 5.5 LCP was applied to the dorsal surface of 1 randomly selected bone from each pair and an 8‐hole, 4.5 LCP was applied dorsally to the contralateral bone from each pair using a combination of cortical and locking screws. All plates and screws were applied using standard ASIF techniques. All MC3 bones had middiaphyseal osteotomies. Mean test variable values for each method were compared using a paired t‐test within each group with significance set at P<.05. Results: Mean yield load, yield bending moment, composite rigidity, failure load, and failure bending moment, under 4‐point bending, single cycle to failure, of the 5.5 LCP fixation were significantly greater than those of the 4.5 LCP fixation. Mean cycles to failure in 4‐point bending of the 5.5 LCP fixation (170,535±19,166) was significantly greater than that of the 4.5 LCP fixation (129,629±14,054). Mean yield load, mean composite rigidity, and mean failure load under torsional testing, single cycle to failure was significantly greater for the broad 5.5 LCP fixation compared with the 4.5 LCP fixation. In single cycle to failure under torsion, the mean±SD values for the 5.5 LCP and the 4.5 LCP fixation techniques, respectively, were: yield load, 151.4±19.6 and 97.6±12.1 N m; composite rigidity, 790.3±58.1 and 412.3±28.1 N m/rad; and failure load: 162.1±20.2 and 117.9±14.6 N m. Conclusion: The 5.5 LCP was superior to the 4.5 LCP in resisting static overload forces (palmarodorsal 4‐point bending and torsional) and in resisting cyclic fatigue under palmarodorsal 4‐point bending. Clinical Relevance: These in vitro study results may provide information to aid in selection of an LCP for repair of equine long bone fractures. 相似文献
957.
The determination of the pharmacokinetic parameters of tramadol in plasma and a better characterization of its metabolites after oral administration to horses is necessary to design dosage regimens to achieve target plasma concentrations that are associated with analgesia. The purpose of this study was to determine the pharmacokinetics and elimination pattern in urine of tramadol and its metabolites after oral administration to horses. Tramadol was administered orally to six horses and its half-life, Tmax and Cmax in plasma were 10.1, 0.59 h, and 132.7 ng/mL, respectively. The half-life, Tmax and Cmax for M1 in plasma were 4.0, 0.59 h, and 28.0 ng/mL, respectively. Tramadol and its metabolites were detectable in urine between 1 and 24 h after the administration. In conclusion, the PK data reported in this study provides information for the design of future studies of tramadol in horses. 相似文献
958.
弯曲杆菌污染是人类健康的一大威胁。通常认为该菌仅存在于肉鸡的胃肠道内。然而,美国的一项研究表明该菌也可以存在于其他内脏器官中,甚至存在于1日龄雏鸡体内。 相似文献
959.
Mark H. Hancock Ron W. Summers Andy Amphlett Johanna Willi Gary Servant Alistair Hamilton 《European Journal of Forest Research》2010,129(3):299-312
It has been argued that large ungulates play a key role in natural forest dynamics, but in Britain, the largest native ungulates
(aurochs and elk) are extinct. Cattle could have some similar effects, and are widely used, but rarely tested, for nature
conservation management. Here, we test conservation management with cattle at a native Scots pine Pinus sylvestris forest in Scotland. Our hypotheses were that cattle impacts would (a) increase the abundance of an understorey shrub of conservation
importance, bilberry Vaccinium myrtillus; and (b) increase Scots pine seedling establishment. Two cattle trials were established, one for each objective, based on
a 14-ha plot within the forest, and a 6.1-ha plot at the forest edge. Cattle were introduced for 2 months to both plots, giving
an approximately 100- to 150-fold increase in ungulate biomass per hectare when compared to background deer abundance. The
ground layer vegetation in both treatment and matched control plots was monitored before and after treatment, and subsequently
over a 4-year period. At the within-forest trial, bilberry percent-cover, 4 years after treatment, was 1.9 times higher in
the cattle area than in the control (95% confidence limits 1.6–2.3). Bilberry percent-cover increases were directly related
to the degree of trampling impact on heather Calluna vulgaris, as recorded immediately after the trial. At the forest-edge trial, there were vegetation changes in the cattle plot that
were considered favourable to pine seedling establishment: reduced moss/litter depth and vegetation percent-cover, and increased
ground-level light incidence. However, too few new pine seedlings were found for formal analysis, partly due to unexpectedly
low seed-fall. Nevertheless, the potential for cattle to create conditions that would subsequently promote pine regeneration
was illustrated by the observation of large numbers of new, young pine seedlings at the within-forest cattle plot. We recommend
that managers and researchers collaborate to develop further trials like the ones reported here, to give an improved understanding
of the conditions under which cattle can yield nature conservation benefits in woodlands. 相似文献
960.
Peter Dye Alistair Clulow Eric Prinsloo Vivek Naiken Isabel Weiersbye 《Southern Forests》2016,78(4):307-313
Several hundred mine tailings dams occur in the Witwatersrand Basin Goldfields in central South Africa. Seepage of acid mine drainage (AMD) from these unlined structures is widespread, and a variety of contaminants is released into soil and groundwater. The ‘Mine Woodlands Project’ is aimed at evaluating the use of high-density tree stands over surrounding contaminant plumes to limit the spread of contaminants through hydraulic control of groundwater and enhanced uptake or immobilisation of contaminants. The annual pattern of hourly sap flow in four contiguous Eucalyptus dunnii trees (aged three years) was followed over a full year in a species trial situated near Carltonville. The annual pattern of hourly sap flow was also recorded in four contiguous sample trees (aged four years) of the clonal hybrid E. grandis × E. camaldulensis (E. G×C) at another trial near Orkney. Both species showed high sap flow rates close to reference evaporation rates in response to summer rains. Both showed greatly reduced sap flow rates during the latter half of the dry winter season. Sap flow rates only recovered after the arrival of the first spring rains. Annual sap flow (E. dunnii, 673 mm; E. G×C, 767 mm) was similar to the recorded annual rainfall at each site (E. dunnii, 629 mm; E. G×C, 795 mm), and was substantially lower than total annual reference evaporation (E. dunnii, 1 273 mm; E. G×C, 1 330 mm). We conclude that the roots of both species are not yet deep enough to access the AMD-influenced groundwater, which lies at depths of 14 and 10 m below the ground at the Carltonville and Orkney sites, respectively. Despite prolonged water deficits, both species survived well and maintained sufficient vigour to permit the quick recovery of high transpiration rates in the following summer. This resilience is essential to hasten root growth and improve the chance of contact with groundwater plumes. 相似文献