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71.
BACKGROUND: Gynaikothrips uzeli Zimmerman was first detected in North America from galls on weeping fig (Ficus benjamina L.) in 2003. It has been reported from ten states in the continental United States, Hawaii, Trinidad and Costa Rica. Adult thrips induce leaves to fold permanently along the midvein, making it a significant pest of weeping fig. Studies were initiated to determine monitoring methods and establish control recommendations.RESULTS: Comparison of captures of adult G. uzeli on blue, yellow, white and green sticky traps found yellow to be the most effective color. Yellow traps were effective for capturing adult Thripastichus gentilei (del Guercio), a larval parasitoid of G. uzeli. Thrips were first captured around 10:00 h. Captures peaked around 15:00-16:00 h and typically ceased by 21:00 h. Systemic neonicotinoid insecticides applied to container media were ineffective against adult G. uzeli feeding on foliage, and foliar applications of these products provided < or =7 days control. Conventional products provided satisfactory control after 1 day, but efficacy declined thereafter. Bifenthrin provided > or = 14 days residual control of adults.CONCLUSION: This paper represents the first report of monitoring phlaeothripids with sticky traps. Data from multiple trials suggest that products effective against other thrips have limited use against G. uzeli. 相似文献
72.
CM Volk JW Elkins DW Fahey RJ Salawitch GS Dutton JM Gilligan MH Proffitt M Loewenstein JR Podolske K Minschwaner JJ Margitan KR Chan 《Science (New York, N.Y.)》1996,272(5269):1763-1768
Airborne in situ observations of molecules with a wide range of lifetimes (methane, nitrous oxide, reactive nitrogen, ozone, chlorinated halocarbons, and halon-1211), used in a tropical tracer model, show that mid-latitude air is entrained into the tropical lower stratosphere within about 13.5 months; transport is faster in the reverse direction. Because exchange with the tropics is slower than global photochemical models generally assume, ozone at mid-latitudes appears to be more sensitive to elevated levels of industrial chlorine than is currently predicted. Nevertheless, about 45 percent of air in the tropical ascent region at 21 kilometers is of mid-latitude origin, implying that emissions from supersonic aircraft could reach the middle stratosphere. 相似文献
73.
Model projections of an imminent transition to a more arid climate in southwestern North America 总被引:5,自引:0,他引:5
Seager R Ting M Held I Kushnir Y Lu J Vecchi G Huang HP Harnik N Leetmaa A Lau NC Li C Velez J Naik N 《Science (New York, N.Y.)》2007,316(5828):1181-1184
How anthropogenic climate change will affect hydroclimate in the arid regions of southwestern North America has implications for the allocation of water resources and the course of regional development. Here we show that there is a broad consensus among climate models that this region will dry in the 21st century and that the transition to a more arid climate should already be under way. If these models are correct, the levels of aridity of the recent multiyear drought or the Dust Bowl and the 1950s droughts will become the new climatology of the American Southwest within a time frame of years to decades. 相似文献
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76.
Summary Attempts have been made to differentiate 9Solanum species and 8 Slovakian cultivars ofS. tuberosum using soluble proteins, isoesterases and antigenic properties of tuber proteins. Soluble proteins were shown to possess the
highest diagnostic value in discriminating between individual species and varieties.S. brevidens of the subsectionEstolonifera deviated from the rest of the species belonging to the subsectionPotatoe. The electrophoretic profiles and immunological responses of individual species only partially correlated with their taxonomic
positions. The highest similarity was observed between the pairs of speciesS. bulbocastanum, S. stenotomum, S. maglia-S. phurea andS. gourlayi-S. vernei. It was possible to differentiate also between individual potato cultivars or between their groups according to both soluble
protein and isoesterase patterns. 相似文献
77.
Sissel Jentoft James A. Held Jeffrey A. Malison Terence P. Barry 《Fish physiology and biochemistry》2002,26(4):371-378
The ontogeny of the cortisol stress response in yellow perch (Perca flavescens) was documented by measuring resting and stress-induced whole-body cortisol levels in fish at several early development stages.
In newly fertilized eggs resting cortisol levels averaged 41.0 ± 3.0 pg/embryo, and decreased to 8.0 ± 3.0 pg/embryo by day
6 where they remained constant until hatch on day 10. Acute stress challenge tests (30 sec cold shock) conducted on embryonic
(days 6 and 8 post-fertilization) and larval (hatch and 2 days post-hatch) yellow perch revealed no differences in whole-body
cortisol levels between stressed and unstressed individuals. In acute stress challenge tests (30 sec net confinement) conducted
on post-hatch yellow perch, differences in cortisol levels between stressed (30 min post-stress) and unstressed fish were
detected one week after hatching (12.3 ± 1.6 ng/g and 7.0 ± 1.3 ng/g, respectively). The magnitude of the stress response
was greater in 2- to 5-week-old fish than in one-week-old fish. Changes in post-stress cortisol levels were closely associated
with changes in interrenal morphology. Cumulatively, these results indicate that cortisol biosynthesis, integration and maturation
of the hypothalamic-pituitary-interrenal (HPI) axis can be observed in yellow perch as early as one week after hatching.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
78.
ABSTRACT Aims: To compare the outcome, in terms of lameness score or return to athletic function, of horses with acute vs. chronic digital lameness that underwent magnetic resonance imaging (MRI) of the distal limb and to compare the proportion of horses that received intra-articular therapy of the distal interphalangeal (DIP) joint and pattern of diagnostic analgesia in these groups. Methods: This is a retrospective study of horses (n?=?95) with acute (≤12 weeks; n?=?46) or chronic (>12 weeks; n?=?49) digital lameness that underwent MRI of the distal limb from 2009–2016, at two equine referral centres in the USA. Criteria for inclusion in the study were that a majority of lameness localised distal to the fetlock, and that lameness assessments for ≥12 months following MRI could be obtained from the medical record or the owner could be interviewed regarding their horse's athletic function. Outcome was characterised by an improvement score where 2?=?return to work at a previous or higher level or lameness improved by one grade or more, 1?=?return to work at a lower level or lameness improved by less than one grade, and 0?=?did not return to work or lameness grade worsened. Whether horses had received intra-articular therapy of the DIP joint and the pattern of diagnostic analgesia prior to MRI was also obtained from medical records or by interviewing the owner. Results: There was a difference (p?=?0.004) in the proportion of horses assigned to improvement scores of 0, 1 and 2 between horses with acute or chronic lameness. There was no evidence of a difference in the likelihood of having received intra-articular therapy of the DIP joint prior to MRI between horses with chronic or acute lameness (p = 0.085). Similarly, there was no evidence of a difference in the pattern of diagnostic analgesia prior to MRI between the two groups (p = 0.94). Eighty-two percent of owners of horses with acute and 62% of those with horses with chronic lameness had a positive opinion of the utility of MRI as a diagnostic modality. Conclusion: In a population of horses with digital lameness undergoing MRI, a difference in the outcome, in terms of lameness score or return to athletic function was identified between horses with acute lameness compared to those with chronic lameness. Clinical relevance: Horses with digital lameness that undergo MRI when the lameness is acute may have an improved prognosis due to accurate diagnosis and earlier application of appropriate therapy. 相似文献
79.
80.
H K Matthews F M Andrews G B Daniel W R Jacobs J P Held 《American journal of veterinary research》1992,53(9):1612-1616
Comparison of standard and radionuclide methods for measuring glomerular filtration rate (GFR) and effective renal blood flow (ERBF) was performed in 8 healthy female horses. Inulin and p-aminohippurate solutions were administered IV as a bolus, followed by sustained administration. Urine and plasma inulin and p-aminohippurate concentrations and urine volume were measured. Glomerular filtration rate and ERBF were calculated on the basis of these measurements. Glomerular filtration rate and ERBF were measured on the basis of plasma clearance of the radiopharmaceuticals, 99mTc-labeled diethylene-triaminepentaacetic acid (99mTc-DTPA) and [131I]-o-iodohippuric acid (131I-OIH), respectively. Mean +/- SEM GFR, using inulin, was 1.83 +/- 0.21 ml/min/kg of body weight. Mean GFR, using 99mTc-DTPA was 1.79 +/- 0.18 ml/min/kg. Mean ERBF, using p-aminohippurate, was 15.13 +/- 1.28 ml/min/kg. Mean ERBF, using 131I-OIH, was 18.42 +/- 1.57 ml/min/kg. Analysis of variance indicated no significant difference between mean values for GFR and ERBF. Radionuclide measurement of GFR and ERBF compared well with standard methods and is an alternative technique to the cumbersome standard methods for determination of GFR and ERBF in horses. 相似文献