全文获取类型
收费全文 | 158篇 |
免费 | 20篇 |
专业分类
林业 | 2篇 |
基础科学 | 2篇 |
20篇 | |
综合类 | 19篇 |
农作物 | 2篇 |
水产渔业 | 14篇 |
畜牧兽医 | 110篇 |
园艺 | 3篇 |
植物保护 | 6篇 |
出版年
2021年 | 10篇 |
2020年 | 3篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2017年 | 7篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 7篇 |
2013年 | 29篇 |
2012年 | 2篇 |
2011年 | 10篇 |
2010年 | 7篇 |
2009年 | 3篇 |
2008年 | 4篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 7篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1974年 | 3篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1970年 | 6篇 |
1968年 | 3篇 |
1967年 | 2篇 |
1966年 | 4篇 |
1965年 | 1篇 |
1964年 | 3篇 |
1938年 | 1篇 |
1927年 | 2篇 |
排序方式: 共有178条查询结果,搜索用时 15 毫秒
81.
Caitlin E. Grant Sarah Dodd Sarah K. Abood Adronie Verbrugghe 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):598
A 6-month-old, intact male Great Dane dog fed a veterinary therapeutic liver diet was evaluated after diagnosis of an intrahepatic portosystemic shunt and hind limb angular limb deformity to determine appropriateness of diet. Evaluation of the current diet revealed it to be inadequate to meet the nutrient requirements of a large breed puppy. The dog clinically improved following a change in diet. There was no longer any angular limb deformity and no reported neurological signs. This report highlights the importance of appropriate feeding management during growth and demonstrates that although veterinary therapeutic diets may appear to be an appropriate choice initially, they may not be ideal for growing puppies as a long-term feeding option.Key clinical message:An individual approach is key for nutritional management of complicated canine veterinary medical cases and includes consideration of the patient’s life stage requirements when modifying nutrient intake to manage clinical disease. 相似文献
82.
Javier Asin Akinyi C. Nyaoke Janet D. Moore Viviana Gonzalez-Astudillo Deana L. Clifford Emma L. Lantz Andrea B. Mikolon Kimberly A. Dodd Beate Crossley Francisco A. Uzal 《Journal of veterinary diagnostic investigation》2021,33(4):728
An outbreak of rabbit hemorrhagic disease virus 2 (RHDV2)-associated disease occurred in the southwestern United States following its first detection in New Mexico in March 2020. The disease spread throughout several states and was diagnosed for the first time in California on May 11, 2020, in a black-tailed jackrabbit (Lepus californicus). The following day, the California Department of Food and Agriculture (CDFA) issued an order banning the entrance into California of several lagomorph species and their products from any state in which the disease had been detected in the last 12 mo. RHDV2 is a threat to wild lagomorph species in California, including the endangered riparian brush rabbit (Sylvilagus bachmani riparius). Therefore, the California Department of Fish and Wildlife (CDFW) started tracking any mortality event in wild lagomorph populations. As of August 9, 2020, RHDV2 had been detected in wild and domestic lagomorphs of several counties in southern California that were submitted to the California Animal Health and Food Safety laboratory system by the CDFA or the CDFW. These positive cases included 2 additional black-tailed jackrabbits and 3 desert cottontail rabbits (Sylvilagus audubonii). In addition, the infection spilled over to domestic populations, whereby it was confirmed on July 10, 2020, in a domestic rabbit (Oryctolagus cuniculus). 相似文献
83.
MR Luz CC de Holanda JJ Pereira PMC Freitas AEP Salgado J Di Giorgio Giannotti SB de Oliveira NS Teixeira CR de Freitas Guaitolini 《Reproduction in domestic animals》2011,46(4):724-727
The embryonic collection techniques in dogs present a vast methodological variation and low recovery rates. The objectives were to compare and describe two techniques as to the recovery of canine embryos, on the 12th day after the first mating or artificial insemination. Embryos were recovered through uterine horn flushing in vivo, before performing the ovariohysterectomy (OHE) (Group 1; n = 9) or ex vivo, immediately after the OHE (Group 2; n = 9). In total, 43 and 47 embryonic structures were recovered in Groups 1 and 2, respectively. There was no significant difference (p > 0.05) between groups on recovery rates (72.8% and 81.0%, respectively). We inferred that both in vivo and ex vivo techniques allow a high rate of embryonic recovery; in the collection technique prior to the OHE, it is essential to carefully handle the reproductive system during the trans‐surgical period and that the 12th day (D12) after the first mating/artificial insemination is an efficient option for the high recovery rate of morulae and blastocysts. 相似文献
84.
Mesodermal control of neural cell identity: floor plate induction by the notochord 总被引:12,自引:0,他引:12
M Placzek M Tessier-Lavigne T Yamada T Jessell J Dodd 《Science (New York, N.Y.)》1990,250(4983):985-988
The floor plate is a specialized group of midline neuroepithelial cells that appears to regulate cell differentiation and axonal growth in the developing vertebrate nervous system. A floor plate-specific chemoattractant was used as a marker to examine the role of the notochord in avian floor plate development. Expression of this chemoattractant in lateral cells of the neural plate and neural tube was induced by an ectopic notochord, and midline neural tube cells did not express the chemoattractant after removal of the notochord early in development. These results provide evidence that a local signal from the notochord induces the functional properties of the floor plate. 相似文献
85.
Sarah L Dodd Alison Stewart 《浙江大学学报(农业与生命科学版)》2004,30(4):466-466
With increased imports of foreign microbes either as commercial biocontrol produ cts or for the purposes of research, there is potentially an increased threat to indigenous beneficial microflora. In the present study, indigenous species of t he fungal genus Hypocrea/Trichoderma are being used as a model system to d etermine the impact of foreign microbes on the native microflora of New Zealand. In order to protect such microflora, one has to first be aware of what is curre ntly present an… 相似文献
86.
Katherine J. Hayden Richard S. Dodd Matteo Garbelotto 《Forest Ecology and Management》2011,261(11):1781-1791
Although tanoak (Notholithocarpus densiflorus syn. Lithocarpus densiflorus) is the species most affected by the introduced pathogen Phytophthora ramorum, with demonstrable risk of extirpation, little is known about the origin, range or structuring of the tree's susceptibility. We examined variation in resistance to P. ramorum using a wound inoculation assay of detached leaves from trees at five geographically separated sites, and a non-wound inoculation assay on twigs from trees at two sites. The structure of variation in resistance was compared to the structure at nine nuclear microsatellite markers.Resistance varied quantitatively, with 23% and 12% of the variation among individuals and populations, respectively. There was a significant correlation between resistance in detached leaves and lesion size in non-wounding twig inoculations. Among-population genetic diversity at nine microsatellite loci was weakly structured but significantly non-zero, with 9.5% of variation among populations. Within-population neutral genetic diversity was a poor predictor of resistance, and estimates of phenotypic distances for resistance were no greater than neutral genetic distances.The limited phenotypic and genetic structure we found indicates that tanoaks at all study sites are susceptible, and there is no evidence of prior selection for disease resistance. We conclude that tanoak populations across the species’ range are at risk, but local disease dynamics will depend on both host genetics and environmental conditions. 相似文献
87.
Carboxyhemoglobin elevation after exposure to dichloromethane 总被引:2,自引:0,他引:2
R D Stewart T N Fisher M J Hosko J E Peterson E D Baretta H C Dodd 《Science (New York, N.Y.)》1972,176(32):295-296
Inhalation of dichloromethane vapor in concentrations of 500 to 1000 parts per million for 1 to 2 hours promptly initiated the formation of significant quantities of carbon monoxide in human subjects. The evidence suggests that carbon monoxide may be a metabolite of dichloromethane and, that exposure to concentrations of dichloromethane below the industrial threshold limit values may result in the formation of carbon monoxide in amounts that exceed the allowable limits. 相似文献
88.
The kinetics of a first-order, solid-solid phase transition were investigated in the prototypical nanocrystal system CdSe as a function of crystallite size. In contrast to extended solids, nanocrystals convert from one structure to another by single nucleation events, and the transformations obey simple unimolecular kinetics. Barrier heights were observed to increase with increasing nanocrystal size, although they also depend on the nature of the nanocrystal surface. These results are analogous to magnetic phase transitions in nanocrystals and suggest general rules that may be of use in the discovery of new metastable phases. 相似文献
89.
Deficit of spinal cord glycine/strychnine receptors in inherited myoclonus of Poll Hereford calves 总被引:4,自引:0,他引:4
A L Gundlach P R Dodd C S Grabara W E Watson G A Johnston P A Harper J A Dennis P J Healy 《Science (New York, N.Y.)》1988,241(4874):1807-1810
Inherited myoclonus of Poll Hereford calves is characterized by hyperesthesia and myoclonic jerks of the skeletal musculature, which occur spontaneously and in response to sensory stimuli. The disease shows autosomal recessive inheritance, and significant proportions of the Poll Hereford herds in many countries are thought to be carriers of the mutant gene. Studies revealed a specific and marked (90 to 95 percent) deficit in [3H]strychnine binding sites in spinal cord membranes from myoclonic animals compared to controls, reflecting a loss of, or defect in, glycine/strychnine receptors. Spinal cord synaptosomes prepared from affected animals showed a significantly increased ability to accumulate [3H]glycine, indicating an increased capacity of the high-affinity neuronal uptake system for glycine. In contrast, stimulus-induced glycine release and spinal cord glycine concentrations were unaltered. 相似文献
90.
Thomas Régnier Jane Dodd Steven Benjamins Fiona M. Gibb Peter J. Wright 《水产资源保护:海洋与淡水生态系统》2021,31(9):2381-2388
- Knowledge of vital data such as growth and age at maturity is necessary to develop effective management strategies for endangered species. The Critically Endangered flapper skate (Dipturus intermedius) is the largest skate in the North Atlantic and growth information, necessary to assess key life-history traits, populations’ growth rates and anticipate their response to management measures, is still lacking.
- While classical age estimation methods used in fish generally require the analysis of calcified structures, destructive methods are incompatible with conservation objectives for this species. Taking advantage of the high recreational value of the flapper skate, this study uses citizen-science data originating from photo-identification of trophy pictures and tag–recapture data supported by anglers to estimate growth in this Critically Endangered species. Using the growth increments measured between recapture events, an individual-based Von Bertalanffy growth model was fitted to the data using Bayesian inference.
- The results confirm that the flapper skate is a long-lived species with ages estimated as >40 years for the largest individuals captured. Despite this longevity, the model reveals a relatively fast initial growth but relatively late ages at maturity and significant sex-related differences in both growth rate and maximum size.
- These results suggest that population growth rate, and therefore recovery, might be much slower than previously reported. By using citizen science this study provides the necessary information to begin understanding population dynamics and monitor the recovery of an iconic Critically Endangered species.