全文获取类型
收费全文 | 358篇 |
免费 | 23篇 |
国内免费 | 3篇 |
专业分类
林业 | 29篇 |
农学 | 3篇 |
基础科学 | 1篇 |
50篇 | |
综合类 | 35篇 |
农作物 | 23篇 |
水产渔业 | 12篇 |
畜牧兽医 | 206篇 |
园艺 | 5篇 |
植物保护 | 20篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 5篇 |
2020年 | 10篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 5篇 |
2014年 | 12篇 |
2013年 | 16篇 |
2012年 | 43篇 |
2011年 | 37篇 |
2010年 | 20篇 |
2009年 | 15篇 |
2008年 | 28篇 |
2007年 | 17篇 |
2006年 | 21篇 |
2005年 | 23篇 |
2004年 | 19篇 |
2003年 | 21篇 |
2002年 | 16篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1968年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有384条查询结果,搜索用时 93 毫秒
331.
G. de la Rebire de Pouyade D. Serteyn G. Deby-Dupont T. Franck 《Research in veterinary science》2009,87(3):358-363
Neutrophil myeloperoxidase (MPO) and elastase can be released in severe inflammatory diseases and cause tissue injuries. Equine enzymes have already been individually purified from large blood quantities. We describe the isolation of both enzymes from a same limited blood volume. Both MPO and elastase were extracted by crushing PMN isolated by centrifugation on a percoll-gradient from a 460 ml blood collection. MPO and elastase were separated by an ionic exchange chromatography phase and further purified by gel filtration chromatography on Superdex 200 and 75, respectively. Enzymes were identified in the collected fractions by specific enzymatic assays. The final purity was verified by electrophoresis. Specific activity was improved to 19.92 and 34.3× for elastase (final yield: 340 μg) and MPO (final yield: 130 μg), respectively, during the procedure. Results show the possibility of isolating both enzymes from the same blood sample with a sufficient yield and purity for future studies on their implication and interaction during inflammatory diseases. 相似文献
332.
333.
The ability of rats to use their whiskers for fine tactile discrimination rivals that of humans using their fingertips. Rats perform discriminations rapidly and accurately while palpating the environment with their whiskers. This suggests that whisker deflections produce a robust and reliable neural code. Whisker primary afferents respond with highly reproducible temporal spike patterns to transient stimuli. Here we show that, with the use of a linear kernel, any of these reproducible response trains recorded from an individual neuron can reliably predict complex whisker deflections. These predictions are significantly improved by integrating responses from neurons with opposite angular preferences. 相似文献
334.
Khalil Elmorjani Nathalie Geneix Michèle Dalgalarrondo Gérard Branlard Didier Marion 《Journal of Cereal Science》2013
Compared to puroindolines a and b, grain softness proteins (Gsp1) remained up to now the less characterized members of this wheat specific seed protein family. Due to their low expression levels, their purification remains relatively arduous. We report in the present work on the purification of wheat Gsp, Gsp1b and its post-translational maturation. We showed that Gsp1b underwent different proteolytic cleavages both in the N and C-terminal extremities of the preproprotein. Especially, after the putative signal peptide, a 29 mer peptide is highlighted that is highly truncated in puroindolines (8–9 mer). We also showed that Gsp1b and puroindolines display similar secondary structure but Gsp1b does not interact in vitro with lipids. In addition, by using the iterative threading assembly refinement (I-TASSER) methods, we showed that Gsp1b three-dimensional structure prediction is however identical to both those of puroindolines and of the dicotyledon 2S storage proteins. In contrast with puroindolines, all these data make us question about the role of Gsp1 proteins in endosperm texture and the previously suggested function in plant defense lent to these proteins. 相似文献
335.
Marie Peeters Denis Verwilghen Didier Serteyn Marc Vandenheede 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(5):311-321
Horse handling and veterinary examination can induce hazardous stress reactions. Such reactions occur especially in young and less-trained horses, particularly stallions, and make their handling a risk for breeders, grooms, and medical staff. Moreover, these stressful situations will affect the animal’s health and welfare. Because stress reactivity is thought to be partly determined by genetic factors, scientists, veterinarians, and breeders are likely to be interested in adding temperament assessments to stallion selection schemes, as it is already done in some countries. This study assesses young stallions’ temperament and its comparison with their stress reactions during a standardized veterinary examination for studbook admission. The assessment consists of a general examination, a lameness examination including flexion tests, an endoscopy of the upper airway, and a standardized radiological examination. During the years 2008 and 2009, 93 stallions were evaluated. Stallions were observed from the moment they were unloaded from the trailer at the clinic until the end of veterinary examinations. In addition to the behavioral observations made by the experimenter, each staff member in charge of the examination filled in a short questionnaire about the horse’s temperament and the “easiness of manipulation” for the performed examinations. Breeders were asked to complete a longer questionnaire about their horse’s temperament. The assessments of “aggressiveness,” “sociability,” and “learning level” temperament traits were the most consistent, as shown by the significant Spearman correlations between judges’ assessments. Undesirable behaviors during veterinary examinations leading to handling difficulties were associated with a low “easiness of manipulation” score assessed by the clinical staff. These low “easiness of manipulation” scores were positively correlated to temperament traits such as “anxiousness” and “aggressiveness” and negatively correlated to others such as “sociability” or “learning level.” Temperament assessment and behavioral observations can therefore be used to anticipate behaviors that make a horse difficult to handle during veterinary examinations. Thus, it may be important to include temperament assessment as a feature in the selection of breeding stallions—as already practiced for some breeds in some countries. Such evaluations may promote the welfare of horses and ease of handling as well as safety for the handler. 相似文献
336.
Khaldi M Socolovschi C Benyettou M Barech G Biche M Kernif T Raoult D Parola P 《Comparative immunology, microbiology and infectious diseases》2012,35(2):117-122
Hedgehogs have become a popular pet despite their potential role in zoonotic disease transmission. We conducted an entomological study in a mountainous region of northeast Algeria in which we collected 387 fleas (Archeopsylla erinacei) and 342 ticks (Rhipicephalus sanguineus and Haemaphysalis erinacei) from Paraechinus aethiopicus and Atelerix algirus hedgehogs. Of the hedgehogs sampled, 77.7% and 91% were infested with fleas and ticks, respectively. Significantly more ticks and fleas were collected from A. algirus than from P. aethiopicus. Rickettsia felis was detected in 95.5% of fleas and R. massiliae was detected in 6.25% of Rh. sanguineus ticks by molecular tools. A new Rickettsia species of the spotted fever group was detected in 11.25% of Rh. sanguineus and in 77% of H. erinacei ticks. Overall, we show that hedgehogs can act as hosts for ectoparasites infected with several rickettsial agents. These data justify a more detailed investigation of animal reservoirs for Rickettsiae. 相似文献
337.
Anne-Sophie Miclot Sabine Wiedemann-Merdinoglu Eric Duchêne Didier Merdinoglu Pere Mestre 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(2):483-495
Powdery mildew caused by Erysiphe necator is one of the most important diseases affecting grapevine (Vitis vinifera, L.). Control of this pathogen is based on the use of fungicides, which cause environmental damage and increase production
costs. A cost-effective and environmentally friendly alternative to control the disease relies on using resistant varieties.
While most V. vinifera cultivars are susceptible to powdery mildew, several species belonging to the Vitaceae have been described as resistant. Several loci for resistance to grapevine powdery mildew have been identified through genetic
analysis of segregating populations derived from different resistance sources. Identifying quantitative trait loci (QTL) with
minor effects on the resistance may prove valuable in a strategy of pyramiding, which aims at increasing the durability of
the resistance. However, current methods for evaluation of resistance either do not take into account quantitative variations,
or, if they do, are not adapted to large sample sets. Here we develop a method for the analysis of quantitative resistance
to grapevine powdery mildew in large populations. We devised a semi-quantitative resistance scale and confirmed the usefulness
of a cell counter to quantify sporulation. We compared three inoculation methods and identified dry inoculation using a settling
tower as the one giving the best infection. Finally, we confirmed the value of the method by applying it to a set of plants
segregating for resistance to E. necator. Using the method described here for the quantitative analysis of the resistance to powdery mildew will prove valuable for
breeding for durable resistance. 相似文献
338.
Patrick Jagoret Isabelle Michel-Dounias Didier Snoeck Hervé Todem Ngnogué Eric Malézieux 《Agroforestry Systems》2012,86(3):493-504
Cocoa cultivation is generally considered to foster deforestation. Contrary to this view, in the forest–savannah interface area in Cameroon, farmers have planted cocoa agroforestry systems on Imperata cylindrica grasslands, a soil-climate zone generally considered unsuitable for cocoa cultivation. We undertook a survey to understand the agricultural and ecological bases of this innovation. Age, cropping history and marketable cocoa yield were assessed in a sample of 157 cocoa plantations established on grasslands and 182 cocoa plantations established in gallery forests. In a sub-sample of 47 grassland cocoa plantations, we inventoried tree species associated with cocoa trees and measured soil organic matter levels. Marketable cocoa yields were similar for the two types of cocoa plantations, regardless of their age: 321?kg?ha?1 in cocoa plantations on grasslands and 354?kg?ha?1 in cocoa plantations in gallery forests. Two strategies were used by farmers to eliminate I. cylindrica prior to the establishment of cocoa plantations, i.e., cropping oil palms in dense stands and planting annual crops. Farmers then planted cocoa trees and fruit tree species, while preserving specific forest trees. The fruit tree and forest tree densities respectively averaged 223 and 68 trees?ha?1 in plantations under 10?years old, and 44 and 27 trees?ha?1 in plantations over 40?years old, whereas the cocoa tree density remained stable at 1,315 trees?ha?1. The Shannon–Weaver index increased from 1.97 to 2.26 over the same period although the difference was not statistically significant. The soil organic matter level was 3.13?% in old cocoa plantations, as compared to 1.7?% in grasslands. In conclusion, our results show that the occupation of grasslands by cocoa agroforestry systems is both an important example of ecological intensification and a significant farmer innovation in the history of cocoa growing. 相似文献
339.
van Galen G Marcillaud Pitel C Saegerman C Patarin F Amory H Baily JD Cassart D Gerber V Hahn C Harris P Keen JA Kirschvink N Lefere L McGorum B Muller JM Picavet MT Piercy RJ Roscher K Serteyn D Unger L van der Kolk JH van Loon G Verwilghen D Westermann CM Votion DM 《Equine veterinary journal》2012,44(5):614-620
Reasons for performing study: Improved understanding of the epidemiology of atypical myopathy (AM) will help to define the environmental factors that permit or support the causal agent(s) to exert toxicity. Objectives: This European survey of AM aimed to describe spatiotemporal distribution, survival, clinical signs, circumstances in which AM develops and its different expressions between countries and over time. Methods: The spatiotemporal distribution, history and clinical features of AM cases reported to the Atypical Myopathy Alert Group from 2006 to 2009 were described. Comparisons of data from the most severely affected countries and from the large outbreaks were made with Fisher's exact and Welch's tests with Bonferroni correction. Results: Of 600 suspected cases, 354 met the diagnostic criteria for confirmed or highly probable AM. The largest outbreaks occurred during the autumns of 2006 and 2009 in Belgium, France and Germany. For the first time, donkeys, zebras and old horses were affected, and clinical signs such as gastrointestinal impaction, diarrhoea, penile prolapse, buccal ulceration and renal dysfunction were observed. Affected horses spent >6 h/day on pastures that almost always contained or were surrounded by trees. The latency period was estimated at up to 4 days. Overall survival rate was 26%. Although differences between countries in affected breeds, body condition, horse management and pasture characteristics were recognised, the common presenting clinical signs and mortality were similar between countries. Conclusions and potential relevance: This study describes new data on case details, history and clinical course of AM that is of preventive, diagnostic and therapeutic value. However, the true impact of the findings of this study on the development of or severity of AM should be tested with case–control studies. 相似文献
340.
Palierne S Asimus E Mathon D Meynaud-Collard P Autefage A 《Research in veterinary science》2006,80(3):243-252
Dogs are often used as experimental models for studies of human hip replacement. A precise knowledge of femoral morphology is required to improve osteointegration of cementless prostheses by bone ingrowth or determination of the best design for total hip prostheses. To better understand the differences between breeds, we measured or calculated 24 external and internal features of the femur on standard radiographs of dogs that differed greatly in size and body type. We considered the appropriateness of the canine model for human total hip replacement studies and show that human and canine femurs differ in characteristics like anteversion, cortico-medullary index or endosteal shape. Knowledge of these differences and similarities makes it possible to design well-adapted stems for dogs. 相似文献