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71.
K.A. Hart G.L. Heusner N.A. Norton M.H. Barton 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(2):344-351
Background: Hypothalamic-pituitary-adrenal (HPA) axis function is dynamic in the neonatal foal. The paired low dose/high dose cosyntropin (ACTH) stimulation test allows comprehensive HPA axis assessment, but has not been evaluated in neonatal foals.
Hypothesis: Foal age will significantly affect cortisol responses to a paired 10 and 100 μg dose cosyntropin stimulation test in healthy neonatal foals.
Animals: Twenty healthy neonatal foals.
Methods: HPA axis function was assessed in 12 foals at birth and at 12–24, 36–48 hours, and 5–7 days of age. At each age, basal cortisol and ACTH concentrations were measured and cortisol responses to 10 and 100 μg cosyntropin were assessed with a paired ACTH stimulation test protocol. Eight additional 36–48-hour-old foals received saline instead of 10 μg cosyntropin in the same-paired ACTH stimulation test design.
Results: At birth, foals had significantly higher basal cortisol and ACTH concentrations and higher basal ACTH : cortisol ratios compared with foals in all other age groups. A significant cortisol response to both the 10 and 100 μg doses of cosyntropin was observed in all foals. The magnitude of the cortisol response to both doses of cosyntropin was significantly different across age groups, with the most marked responses in younger foals. There was no effect of the paired ACTH stimulation test design itself on cortisol responses.
Conclusions and Clinical Importance: A paired 10 and 100 μg cosyntropin stimulation test can be used to evaluate HPA axis function in neonatal foals. Consideration of foal age is important in interpretation of HPA axis assessment. 相似文献
Hypothesis: Foal age will significantly affect cortisol responses to a paired 10 and 100 μg dose cosyntropin stimulation test in healthy neonatal foals.
Animals: Twenty healthy neonatal foals.
Methods: HPA axis function was assessed in 12 foals at birth and at 12–24, 36–48 hours, and 5–7 days of age. At each age, basal cortisol and ACTH concentrations were measured and cortisol responses to 10 and 100 μg cosyntropin were assessed with a paired ACTH stimulation test protocol. Eight additional 36–48-hour-old foals received saline instead of 10 μg cosyntropin in the same-paired ACTH stimulation test design.
Results: At birth, foals had significantly higher basal cortisol and ACTH concentrations and higher basal ACTH : cortisol ratios compared with foals in all other age groups. A significant cortisol response to both the 10 and 100 μg doses of cosyntropin was observed in all foals. The magnitude of the cortisol response to both doses of cosyntropin was significantly different across age groups, with the most marked responses in younger foals. There was no effect of the paired ACTH stimulation test design itself on cortisol responses.
Conclusions and Clinical Importance: A paired 10 and 100 μg cosyntropin stimulation test can be used to evaluate HPA axis function in neonatal foals. Consideration of foal age is important in interpretation of HPA axis assessment. 相似文献
72.
Joseph A. Araujo Christina de Rivera Jennifer L. Ethier Gary M. Landsberg Sagi Denenberg Stephanie Arnold Norton W. Milgram 《Journal of Veterinary Behavior: Clinical Applications and Research》2010,5(5):268-275
Anxiety and fear are common underlying factors in many canine behavior problems that impair the human–pet bond and often result in abandonment, relinquishment, or euthanasia. A combination of behavioral and pharmacological interventions is used to ameliorate the behavioral signs associated with anxiety-related behaviors in dogs, but there continues to be need for effective interventions. The current study examined the effects of the nutraceutical ANXITANE® (l-Theanine) chewable tablets on fear of unfamiliar human beings. We first characterized dogs as anxious on the basis of the existence of a fear response to human beings in their home-pen. We then demonstrated that dogs characterized as anxious (N = 10) showed reduced interaction with an unknown human being as compared with normal controls (N = 7). The effect of an administration of ANXITANE® tablets (N = 5) on these anxious Beagle dogs was compared with placebo (N = 5). Objective behavioral measures of anxiety were obtained using an open-field test, a human interaction test, and an actiwatch protocol that allowed monitoring of activity over 24-hours. The ANXITANE® tablets-treated dogs showed greater human interaction and approach than the placebo control group, and no side effects related to treatment, including motor stimulant or sedative effects, were seen. The current study suggests that ANXITANE® tablets are effective for reducing fearful behavior toward unfamiliar human beings in dogs and supports their use for treating anxiety-related behaviors. 相似文献
73.
Michael Norton Gert-Jan van Sprundel Calum G. Turvey Miranda P.M. Meuwissen 《国际虫害防治杂志》2016,62(3):195-204
In this paper, we explore the application of weather index insurance to plant pest and disease management strategies using two distinct models: (1) insuring crop loss due to disease incidence (“Crop Insurance”) and (2) insuring the use of pesticides (“Pesticide Insurance”). We find that despite the seeming ease of applying weather-based pest incidence models to an insurance product, insuring plant disease incidence models is presently unsuitable for the insurance market for both scientific and behavioral reasons. However, derivative-like applications of weather index insurance to insure pesticide use offer a means to introduce financial leverage into pesticide usage decisions. Risk management with weather index insurance would thus function as a complement to existing risk management strategies using pesticides, and offer a market-based mechanism for pesticide abatement. We conclude that more interdisciplinary collaboration is needed to develop weather index insurance for remuneration of losses due to plant pests and diseases, but weather index insurance offers a potential mechanism to reduce inefficiencies and negative externalities in agricultural markets if pesticide expenditures are insured instead of crop losses. 相似文献
74.
Farrah R. Fatemi Ivan J. Fernandez Johanna Szillery Stephen A. Norton Lindsey E. Rustad 《Water, air, and soil pollution》2012,223(9):6171-6186
We examined long-term changes in soil solution chemistry associated with experimental, whole watershed-acidification at the Bear Brook Watershed in Maine (BBWM). At BBWM, the West Bear (WB) watershed has been treated with bimonthly additions of ((NH4)2 SO4) since 1989. The adjacent East Bear (EB) watershed serves as a biogeochemical reference. Soil solution chemistry in the EB watershed was relatively stable from 1989?C2007, with the exception of declining SO4?CS concentrations associated with a progressive decline in SO4?CS deposition during this period. Soil solution chemistry in WB reflected a progressive change in acid-neutralization mechanisms from base cation buffering to Al buffering associated with treatment during this period. Total dissolved Al concentrations progressively increased over time and were ~4× higher in 2007 than in 1989. Treatment of WB was also associated with long-term increases in soil solution H+, SO4?CS, and NO3?CN, whereas soil solution dissolved organic carbon (DOC) was unresponsive to treatment. For solutes such as Ca, H+, and SO4?CS, changes in stream chemistry were generally parallel to changes in soil solution chemistry, indicating a close coupling of terrestrial and aquatic processes that regulate the chemistry of solutions in this first-order stream watershed. For other solutes such as Al and DOC, solute concentrations were higher in soil solutions compared with streams, suggesting that sorption and transformation processes along hydrologic flow-paths were important in regulating the chemistry of solutions and the transport of these solutes. 相似文献
75.
M Vignoli M Russo G Catone F Rossi G Attanasi R Terragni JH Saunders GCW England 《Reproduction in domestic animals》2011,46(2):209-213
Vascular perfusion was assessed in 10 dogs without prostatic abnormalities and 26 dogs with prostatic disease using contrast‐enhanced ultrasound. The time to reach peak contrast intensity (TTP) and peak perfusion intensity (PPI) were measured, and histological biopsies were collected from each dog. Biopsies confirmed normal prostate (n = 10), benign prostatic hyperplasia (n = 11), mixed benign pathology (n = 9), prostatitis (n = 1), prostatic malignancy [adenocarcinoma (n = 4); leiomyosarcoma (n = 1)]. In normal dogs, mean PPI was 16.8% ± 5.8 SD, and mean TTP was 33.6 ± 6.4 s. Benign conditions overall were not statistically different from normal dogs (p > 0.05); for benign prostatic hyperplasia, mean PPI was 16.9 ± 3.8%, and mean TTP was 26.2 ± 5.8 s; for mixed benign pathology mean PPI was 14.8 ± 7.8%, and mean TTP was 31.9 ± 9.7 s; for prostatitis, PPI was 14.2%, and TTP was 25.9 s. The malignant conditions overall had perfusion values that differed from the normal dogs (p < 0.05), although evaluation of the data for individual malignancies did not demonstrate a consistent trend; for adenocarcinomas, the PPI was numerically higher with a mean of 23.7 ± 1.9%, and the mean TTP was 26.9 ± 4.8 s, whilst for the dog with leiomyosarcoma values were numerically lower with a PPI of 14.1% and TTP of 41.3 s. Contrast‐enhanced ultrasound appears to offer some ability to document differences in perfusion that may differentiate between malignant and benign lesions, although studies with larger numbers of animals are required to confirm this contention. 相似文献
76.
Oslan Jumadi St. Fatmah Hiola Yusminah Hala Jeanette Norton 《Soil Science and Plant Nutrition》2013,59(5):722-730
Azolla microphylla Kaulf. (Azolla) biomass was composted to create a high nitrogen (N) organic matter amendment (Azolla compost). We examined the effect of this Azolla compost on carbon (C) and N mineralization and the production of biogenic gases, nitrous oxide (N2O) and carbon dioxide (CO2), in a soil incubation experiment. A pot experiment with upland kangkong (Ipomoea aquatica Forsk.) examined plant growth in silt loam soil treated with three levels of Azolla compost. The results showed that N2O production from soil increased with urea amendment, but not with Azolla compost treatments. The Azolla-amended soil showed enhanced CO2 production throughout the 4-week incubation. The Azolla-treated soils showed a 98% lower global warming potential compared to urea treatment over the 4-week incubation. However, Azolla-amended soil had higher nitrate (NO3–) levels compared to urea-fertilized soil at 1 week of incubation, and these were maintained until the fourth week. Soils amended with Azolla compost showed lower ammonium nitrogen (NH4-N) levels than those in the urea-fertilized soils. The height and dry weight of upland kangkong fertilized with Azolla compost were similar to plants receiving urea fertilization. Therefore, the use of Azolla compost as a substitute for urea fertilizer would be beneficial for reducing the production of N2O while maintaining plant growth. 相似文献
77.
Crane M Norton A Leaman J Chalak A Bailey A Yoxon M Smith J Fenlon J 《Pest management science》2006,62(1):5-19
EU Directive 91/414/EEC requires there to be no unacceptable effects on the environment from the use of pesticides. This paper reports the views of direct stakeholder groups and results from an opinion survey of more than 2000 members of the general public on what in practice should constitute acceptable and unacceptable effects of pesticides. Stakeholders in focus groups were concerned with the potential effects of pesticides on animal and plant population viability and micro-organism function but recognized that a trade-off exists between the potential economic advantages of responsible pesticide use and the potential disadvantages of individual poisoning events. The public opinion survey showed that although pesticides are widely used in homes and gardens, their use on farm crops remains of concern to the public. Concerns are greatest on issues of human health and food quality but potential environmental effects are also an issue for a substantial number of people, particularly if attractive species could be affected. 相似文献
78.
在家禽的身体表面和内部及其生活的环境中均有大量的细菌存在,同其它动物一样,家禽在呼吸、采食和饮水时均摄入大量的细菌。当细菌大量繁殖超过机体的防御能力或机体的防御能力下降时就会引起发病。厌氧菌存在于动物身体的各个部位,甚至在肺部,而且数量超过需氧菌,达100∶1。同其它细菌一样,厌氧菌有其生长需求,并同其它细菌保持一种平衡,正常情况下不致病。只有当条件变化这种平衡打破后厌氧菌才会大量繁殖引起发病。许多厌氧菌是内源性的,正常情况下存在于体内但数量较少,只有在各适条件下才繁殖并引起发病。引起厌氧菌内源性繁殖和感染的… 相似文献
79.
80.
T M Norton W H Adams G V Kollias V L Clyde 《Journal of the American Veterinary Medical Association》1990,197(5):630-632
Benign prostatic hyperplasia, diskospondylitis at the T13-L1 intervertebral disk space, and penile paresis were diagnosed in a 16-year-old male ocelot. Treatment consisted of castration for the benign prostatic hyperplasia and long-term administration of antibiotics for the diskospondylitis. On physical examination 8 weeks after initial referral, the prostate gland was no longer palpable and could not be visualized radiographically or ultrasonographically. The diskospondylitis lesion was found to be healing, on the basis of radiographic results. 相似文献