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71.
A 12-month-old American Miniature horse colt was presented to the Virginia Tech Veterinary Teaching Hospital with a 7-month history of progressive ataxia. Physical examination revealed a head intention tremor, base-wide stance, and ataxia. Necropsy findings were confined to the brain. There were bilateral areas of liquefactive necrosis and cavitation corresponding to the dorsal accessory olivary and lateral (accessory) cuneate nuclei. Cerebellar folia of the dorsal vermis were thin. Microscopically, the cerebellar cortex was characterized by patchy areas of Purkinje cell loss with associated variable thinning of the molecular and granule cell layers and astrogliosis. Dorsal accessory olivary and lateral cuneate nuclei were cavitated and had mild glial response around their periphery. Additionally, a focus of necrosis and neuropil vacuolization was found in the right putamen. These findings indicate the presence of a neurodegenerative disorder centered, but not confined to, the cerebellum and its connections in this American Miniature horse colt. 相似文献
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73.
Paul G. Scowcroft James B. Friday Janis Haraguchi Travis Idol Nicklos S. Dudley 《Small-Scale Forestry》2010,9(2):243-262
Providing economic incentives to landholders is an effective way of promoting sustainable forest management, conservation
and restoration. In Hawaii, the main native hardwood species with commercial value is Acacia koa (koa), but lack of successful examples of koa plantation forestry hinders private investment. Financial models, which have
been offered to encourage investment, assume that a particular minimum volume of merchantable wood will be harvested at rotation
age. No studies have been done to determine the appropriateness of the assumed volumes for koa plantations. Three 18- to 28-year-old
koa plantations were studied to determine butt-log size, crown class and crop tree potential. Estimates of present and future
merchantable sawtimber volume were made for each plantation. Results indicate that most existing plantation koa trees fork
so close to the ground that they will produce little to no merchantable wood. Projected sawtimber yields from crop trees in
these plantations at age 45 years are 10, 15 and 90 m3/ha, which are below the 135 m3/ha yield used in the most recent financial analysis of returns on investment in koa forestry. Relaxing the crop tree criteria
gives higher volume yields, but two plantations still fall short of the assumed target yield by 43 and 52%. Given such shortfalls,
returns on investment will be less than predicted by the financial analysis. Nevertheless, government offered financial incentives
should compensate for lower volume yields and thus promote private investment in koa plantation forestry. Insect herbivory,
genetic diversity, and low stand density contribute to poor stem form of plantation koa, and research is needed to quantify
the relative importance of and interactions between these factors. 相似文献
74.
Wade P. Heller Marc A. Hughes Blaine C. Luiz Eva Brill James B. Friday Adam M. Williams Lisa M. Keith 《Forest Pathology》2019,49(5)
The fungus Ceratocystis huliohia was detected for the first time in dead and dying Metrosideros polymorpha trees on the Island of Kaua?i, Hawai?i, U.S.A. Fungal isolates were recovered from diseased trees into culture, and identities were confirmed by diagnostic qPCR assay and DNA sequencing. Growth chamber inoculations confirmed C. huliohia pathogenicity on M. polymorpha seedlings and subsequently the same fungus was recovered, completing Koch's postulates. DNA sequence analysis revealed a unique ITS haplotype for Kaua?i isolates of C. huliohia that has not been found on Hawai?i Island. 相似文献
75.
Bamidele O. Omitoyin Emmanuel K. Ajani Olugbenga Orisasona Happiness E. Bassey Kazeem O. Kareem Friday E. Osho 《Aquaculture Research》2019,50(7):1851-1861
An 84‐day feeding trial was carried out to evaluate the effects of aqueous Psidium guajava leaf extract (PGE) on growth, intestinal morphology, physiology, immune response and susceptibility of Oreochromis niloticus to Aeromonas hydrophila. Diets containing 0% (P0), 0.25% (P1), 0.50% (P2), 0.75% (P3) and 1.00% (P4) PGE were fed to triplicate groups of fish (mean weight; 1.32 ± 0.04 g) for 84 days. After the 84‐day feeding trial, test fish were injected with pathogenic A. hydrophila and then fed for 14 days. More feed were consumed in groups of fish fed PGE‐treated diets and resulted in significantly higher weight gain and feed intake. Incidentally, there was an increase in the calculated area of absorption of fish fed PGE diets, as accounted for by marginally higher villi length and width. Antioxidant and immune response were improved with PGE inclusion in diets as total protein, superoxide dismutase, glutathione peroxidase and glutathione S‐transferase significantly increased (p < 0.05) in fish fed PGE diets. Results of the challenge test with A. hydrophila revealed that the highest mortality (100%) was recorded in P0. This study revealed that inclusion of P. guajava extract in the diet of O. niloticus improved growth, nutrient utilization, immune system and survival of O. niloticus fingerlings. 相似文献
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77.
Urinary catheterisation of female dogs: a comparison between three techniques for catheter placement
AE Tipler EA Moses R Greer P Delisser BD McCracken PA Moses 《Australian veterinary journal》2020,98(8):364-370
The objective of this study was to describe a new technique for urinary catheterisation of female dogs using a novel catheterisation device (NCD) and to compare the time taken to place a catheter using this technique with traditional techniques. A secondary objective was to survey participants on which of the techniques they preferred. Female canine cadavers of varying sizes were utilised and veterinary students who had not previously placed a urinary catheter were enrolled. Each participant performed three catheterisation techniques, Visual with speculum (SPEC), Blind Palpation (BP) and catheterisation with NCD on three sizes of dog. Time required using each technique was compared using Kaplan–Meier plots and mixed models Cox Proportional Hazards regression. Median times to catheterisation were 300 s (IQR 261–417 s) with the SPEC method, 420 s (IQR 253–545 s) with the NCD method and 725 s (574–1032s) with the BP method. Both SPEC and NCD methods were significantly faster compared to the BP method, with Hazard Ratios of 3.66 (95% CI 1.94–6.91, P < 0.001) and 3.57 (95% CI 1.87–6.81, P < 0.001), respectively. Six of nine participants found the NCD the easiest technique, 5/9 of the participants found the palpation technique most difficult and 4/9 found the speculum technique most difficult. BP appears to be the technique of least preference and increased time requirement. The novel urinary catheterisation device may provide a simpler method of visualisation of the urethral papilla and may provide a more sterile way of placing the catheter, although further investigation is needed to confirm this. 相似文献
78.
Competition for light between hedgerows and maize in an alley cropping system in Hawaii, USA 总被引:4,自引:0,他引:4
Successful agroforestry systems depend on minimizing tree-cropcompetition. In this study, field experiments and a simulation
model were usedto distinguish between tree-crop competition for light and belowgroundcompetition in an alley cropping system.
Maize (Zea maysL.) was harvested periodically in three treatments: between vertical barriers ofshade cloth, hedgerows of Flemingia macrophylla (Willd.)Merr., and sole maize. Radiation intercepted by the maize was calculated using asimulation model based on measured
values for direct and diffuse light, hedgerowdimensions and leaf area, and solar trajectory. Radiation use efficiency wascalculated
as biomass production per unit of intercepted radiation. Maizebiomass and yield in both the alley crop and the shade cloth
treatment weregreatest in the center of the alleys. Grain yield between hedgerows was 3.5Mg ha−1 (averaged across the alley), significantlyless than in the shade cloth (7.4 Mg ha−1) or thesole maize (7.7 Mg ha−1) treatments. Lightintercepted by the maize in the alley crop was about half that intercepted bythe maize in the sole crop.
The shade cloth intercepted less light than thehedgerows because it did not have an appreciable width. Radiation use efficiencyin
the three treatments was 0.75 g mol−1 PAR anddid not differ significantly among treatments. Tree-crop competition wasoverwhelmingly for light.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
79.
The second in this series of clinical reviews on neurological diseases in ruminant livestock in Australia examines toxic disorders associated with plant and microbial toxins as well as the neurological effects of vitamin and mineral deficiencies. The aim of these reviews is to assist in the surveillance of neurological diseases, especially the transmissible spongiform encephalopathies. 相似文献
80.