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101.
Positive plant–soil feedbacks of the invasive Impatiens glandulifera and their effects on above‐ground microbial communities 下载免费PDF全文
Impatiens glandulifera is one of the most widespread invasive plant species in the UK. Although aspects of its biology are known, there is little information about its association with microbial communities, both above ground and below ground. Furthermore, it is unknown whether this species exhibits any form of plant–soil feedback (PSF), commonly seen in other invasive weeds. We conducted a PSF experiment, in which plants of I. glandulifera were grown in soil that supported the species and compared with plants grown in a control soil from the same locality. Soil nutrients were measured, and the soil and foliar microbial communities were assessed. Impatiens glandulifera grew larger and faster in conditioned soil compared with the control. Higher levels of phosphate were also found in conditioned soils. Arbuscular mycorrhizal fungal (AMF) colonisation was lower in conditioned soils, suggesting that I. glandulifera may rapidly alter AMF communities in invaded areas. PSFs had a significant effect on the foliar endophyte community, with clear separation of species between conditioned and control soils. These results show that I. glandulifera displayed a positive PSF and the PSF mechanism extended beyond the soil microbial community to affect foliar endophytes. The observed increase in endophytes in plants grown in conditioned soil could enhance resistance to herbivory, thus further accentuating the invasive properties of this species. 相似文献
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Chris W. Rogers Charlotte F. Bolwell Jasmine C. Tanner P. Rene van Weeren 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(6):375-379
Across all equestrian disciplines, the single largest reason for wastage is musculoskeletal injury. It is, therefore, of importance that management and competition structures are in place to optimize the development of the equine musculoskeletal system to minimize wastage.Data from other species and, in particular, humans have demonstrated the benefit of early exercise and the dire consequences of inactivity. The horse has evolved as a cursorial animal capable of covering up to 10 km/d within 9 days of birth. Yet, modern equine management systems restrict, rather than promote, early exercise. Foals were shown to have a positive response to early preweaning paddock exercise (greater cartilage health), and more recent work has demonstrated that exercise over and above that normally occurring with pasture-reared foals, introduced as early as 3 weeks old, had positive effects on the equine musculoskeletal system. The response of juvenile horses to additional exercise is because of the tissue being responsive to priming. Epidemiological data indicate that the window for tissue modification may still be open when the horse is a yearling and even as a 2 year old.However, the method in which the exercise is applied may be of as much importance as the timing of the stimuli. A recent prospective study of both Thoroughbred and Standardbred horses demonstrated that the horses that entered training as 2 year olds had longer and more successful racing careers than those that entered training later in life. It would appear that even the initial stages of training are enough to provide a positive stimulus, as horses first registered with a trainer at 2 years old had the same advantages as those that raced as 2 year olds.The physiological, clinical, and epidemiological data indicate that, rather than restrict exercise and the use of horses at a young age, we should realign expectations with the capability of the horses’ musculoskeletal system and evolutionary template to maximize orthopedic health. 相似文献
104.
Wiley PR Tanner GJ Chandler PM Anderssen RS 《Journal of agricultural and food chemistry》2009,57(10):4042-4050
Near-infrared reflectance (NIR) spectroscopy was used in the characterization of grain morphology mutants of barley ( Hordeum vulgare L.) in relation to grain nitrogen (N) content and protein composition. Derivative spectroscopy provided spectra with enhanced resolution, allowing wavelengths to be identified with clear differences in contribution from associated chemical bonds. Comparisons of fourth-derivative spectra of wholemeal flour from high-N grains with flour from low-N grains identified wavelengths at which there were statistically significant differences between the groups. Their importance was independently confirmed by step-up regression using these wavelengths to generate an equation predicting N content (R(2) = 0.98). Fourth-derivative spectral comparisons also allowed novel biochemical differences to be predicted. Visual assessment of the spectra of all mutants revealed a variable region (1470-1520 nm, corresponding to N-H stretch vibrations) that allowed two extreme sets to be defined. The protein extracted from these two sets differed markedly in hordein content. 相似文献
105.
Monica Natalie Wymann Bassirou Bonfoh Esther Schelling Skouba Bengaly Saïdou Tembely Marcel Tanner Jakob Zinsstag 《Livestock Science》2006,100(2-3):169-178
Calf mortality rate and causes of death were studied in peri-urban livestock production systems in Bamako, Mali, for calves born and dying from November 2002 to March 2004. Causes of death for 93 deceased calves were diagnosed from clinical autopsies, reported history of death and parasitic information. Calves originated from traditional, modernized and station management systems. Overall mortality rate was 17% during the first year of life (N = 756 live-births). Mortality rate was significantly lower for traditionally (10%) compared to modernized (19%) or to station managed calves (25%). Total perinatal loss (abortions + stillbirths + perinatal mortality) was 5% (N = 784 gestations). The most important death categories were digestive tract disorders (28%), perinatal mortality (16%) and accidents (14%). Vector-borne and infectious diseases were of low importance. Digestive tract disorders and perinatal mortality were the most important categories of death in modernized management while accidents and starvation were the most important causes of death in traditional management. Digestive tract disorders were more common in modernized than in traditional management (p = 0.02), revealing a serious problem with hygiene in stationary enclosures. With better calf management in regard to hygiene, surveillance and control of milk off-take, overall calf survival may be increased and peri-urban livestock production made more profitable. 相似文献
106.
SUMMARY: Infection by the metacestodes of Echinococcus multilocularis is an example of the biological paradox of a proliferating parasite in an immunologically-competent host. There is evidence that infection with these organisms is regulated. A study of this regulation has shown that hydatid cysts can be effectively treated with complement and that the cellular defence mechanisms of the host can be non-specifically activated with BCG; treatment with BCG presents an effective prophylactic measure against infection with E. multilocularis . The mechanisms by which parasite infections are regulated can furnish clues to possible prophylactic and therapeutic strategies. 相似文献
107.
Occurrence of canine parvovirus type 2c in the United States. 总被引:3,自引:0,他引:3
Charles Hong Nicola Decaro Costantina Desario Patrick Tanner M Camila Pardo Susan Sanchez Canio Buonavoglia Jeremiah T Saliki 《Journal of veterinary diagnostic investigation》2007,19(5):535-539
Canine parvovirus (CPV) type 2 (CPV-2) emerged around 1978 as a major pathogen of dogs worldwide. In the mid-1980s, the original CPV-2 had evolved and was completely replaced by 2 variants, CPV-2a and CPV-2b. In 2000, a new variant of CPV (named CPV-2c) was detected in Italy and now cocirculates with types 2a and 2b in that country. The CPV-2c has also been reported from single outbreaks in Vietnam and Spain. This study was conducted to determine if CPV-2c occurs in the United States. Thirty-three fecal samples were collected from dogs in 16 states between April 2006 and April 2007 and were tested for CPV using real-time polymerase chain reaction (PCR). Positive samples were further tested using conventional PCR and minor-groove binding TaqMan PCR assays to determine the viral type and to differentiate vaccine strains from field strains. Twenty-seven samples were positive for CPV, 7 of which were CPV-2c from 5 states: Arizona, California, Georgia, Oklahoma, and Texas. Of the 7 isolates, 4 differed from European CPV-2c isolates by 2 additional single-nucleotide mutations at positions 4076 and 4104, the latter of which produces a ThrAla change at residue 440 located near a major antigenic site. The coast-to-coast geographic distribution of the states in which CPV-2c was detected strongly suggests that this new CPV variant is probably widespread in the United States. The continuous evolution of CPV requires that monoclonal antibody-based and nucleic acid-based diagnostic assays should be periodically checked for sensitivity on prevalent CPV strains. 相似文献
108.
R. Tanner A. Orlinski J. Meyer M. Ward S. Luki M. Glavendeki D. McCann 《EPPO Bulletin》2019,49(2):298-300
An EPPO Contingency Planning Workshop for a Forestry Pest was held in Zlatibor, Serbia, between 27 and 29 November 2018. In total, 55 experts from 21 EPPO member countries attended the 3‐day workshop. Participants were split into four groups for the exercise and each group acted as an ‘outbreak management team’ for a scenario based on the finding of a quarantine pest for forestry. Only when the exercise had started were participants informed that the outbreak scenario centred around the fictitious discovery of pinewood nematode (Bursaphelenchus xylophilus) in the Tara National Park in Serbia. As the scenario developed, each team had to organize themselves to manage a number of issues designed to mimic the development of an outbreak over the first month following its detection. It was clear from the feedback from participants that that contingency planning workshop was a valuable exercise for EPPO to conduct and participants highlighted the importance of it to prepare themselves for real‐life situations. 相似文献
109.
OBJECTIVE: To assess the effectiveness of cholecalciferol (D3) doses for maintaining adequate vitamin D status in crias and adult female alpacas at pasture. DESIGN: A field experiment during winter and early spring in a herd on a farm in South Australia. ANIMALS AND PROCEDURE: Crias, usually less than 6 months of age and female alpacas, aged 2 to 6 years, were given a single subcutaneous dose of 0, 1000 or 2000 IU D3/kg body weight. Plasma concentrations of 25-hydroxycholecalciferol (25-OH D3), phosphorus, calcium and vitamins A and E and alkaline phosphatase activity were measured at intervals over a period of 16 weeks after treatment. RESULTS: Crias not given a vitamin D supplement had reduced growth rate during winter and one animal showed clinical signs of rickets. Vitamin D treatment had no effect on the body weight of mature females. Vitamin D supplements increased the 25-OH D3 and phosphorus concentrations in plasma of both crias and adult females; alkaline phosphatase activity was not affected by treatment. CONCLUSION: It is suggested that for alpacas in southern Australia a subcutaneous dose of 1000 IU D3/kg body weight to crias in late autumn and again in mid winter and to adult females in mid winter should prevent vitamin D inadequacy. 相似文献
110.