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81.
Antimicrobial resistance of fecal Escherichia coli isolated from grow-finish pigs in 20 herds in Alberta and Saskatchewan. 下载免费PDF全文
Leigh B. Rosengren Cheryl L. Waldner Richard J. Reid-Smith Sylvia L. Checkley Margaret E. McFall Andrijana Raji? 《Canadian journal of veterinary research》2008,72(2):160-167
Escherichia coli (n = 1439), isolated from the feces of apparently healthy grow-finish pigs in 20 herds in Alberta and Saskatchewan, were tested for susceptibility to 16 antimicrobials. All isolates were susceptible to amikacin, ceftriaxone, and ciprofloxacin and less than 1% was resistant to amoxicillin-clavulanic acid, cefoxitin, ceftiofur, gentamicin, and nalidixic acid. Resistance was most common to tetracycline (66.8%), sulfamethoxazole (46.0%) and streptomycin (33.4%). Twenty-one percent of the isolates were susceptible to all drugs, while 57% were resistant to 2 or more antimicrobials. Unconditional associations between resistances provided insight into the potential for co-selection. Every resistance-outcome was associated with at least 2 other drug-resistances. These associations illustrate the propensity for resistance phenotypes to occur together and the importance of considering co-selection in antimicrobial use decisions. A 2nd analysis explored the associations between resistance phenotypes in E. coli and Salmonella spp. from the same herd. Only 2 resistances in Salmonella were associated with herd-level E. coli resistance, indicating that E. coli is a poor sentinel for Salmonella AMR within herds. Herd-level management, including antimicrobial use, could affect antimicrobial resistance. The intra-class correlation between isolates within herds ranged from 0.1 to 0.46, which confirmed resistance clustered within herds. This suggests herd-level interventions might mitigate antimicrobial resistance. Overall, these results reflect the on-farm selection pressure for resistance and the potential food-safety risk from near-market animals. These data provide a baseline for comparisons with future on-farm monitoring of antimicrobial resistance in E. coli. 相似文献
82.
Ellen G. Murphy Nicola J. Williams Daisy Jennings Julian Chantrey Ranieri Verin Sylvia Grierson Lorraine M. McElhinney Malcolm Bennett 《Zoonoses and public health》2019,66(6):686-694
In the United Kingdom, there has been an increase in the number of hepatitis E virus (HEV) infections in people annually since 2010. Most of these are thought to be indigenously acquired Orthohepevirus A genotype 3 (HEV G3), which has been linked to pork production and consumption. However, the dominant subgroup circulating in British pigs differs from that which is found in people; therefore, an alternative, potentially zoonotic, source is suspected as a possible cause of these infections. Rodents, brown rats (Rattus norvegicus) in particular, have been shown to carry HEV, both the swine HEV G3 genotype and Orthohepevirus C, genotype C1 (rat HEV). To investigate the prevalence of HEV in British rodents, liver tissue was taken from 307 rodents collected from pig farms (n = 12) and other locations (n = 10). The RNA from these samples was extracted and tested using a pan‐HEV nested RT‐PCR. Limited histopathology was also performed. In this study, 8/61 (13%, 95% CI, 5–21) of brown rat livers were positive for HEV RNA. Sequencing of amplicons demonstrated all infections to be rat HEV with 87%–92% nucleotide identity to other rat HEV sequences circulating within Europe and China (224 nt ORF‐1). Lesions and necrosis were observed histologically in 2/3 samples examined. No rat HEV RNA was detected in any other species, and no HEV G3 RNA was detected in any rodent in this study. This is the first reported detection of rat HEV in Great Britain. A human case of rat HEV infection has recently been reported in Asia, suggesting that rat HEV could pose a risk to public health. 相似文献
83.
1. Videotapes of hens under various conditions were used to measure the amount of space used by hens performing common behaviour patterns.
2. When turning, hens used 540 to 1006 cm2, when stretching wings 653 to 1118 cm2, when wing flapping 860 to 1980 cm2, when feather ruffling 676 to 1604 cm2, when preening 814 to 1270 cm2 and when ground scratching 540 to 1005 cm2.
3. All these measurements are above the 450 cm2 bird recommended as the minimum space allowance by current EC regulations, which therefore do not ensure adequate hen welfare. 相似文献
84.
Hogenkamp A Isohadouten N Reemers SS Romijn RA Hemrika W White MR Tefsen B Vervelde L van Eijk M Veldhuizen EJ Haagsman HP 《Veterinary microbiology》2008,130(1-2):37-46
Many proteins of the calcium-dependent (C-type) lectin family have been shown to play an important role in innate immunity. They can bind to a broad range of carbohydrates, which enables them to interact with ligands present on the surface of micro-organisms. We previously reported the finding of a new putative chicken lectin, which was predominantly localized to the respiratory tract, and thus termed chicken lung lectin (cLL). In order to investigate the biochemical and biophysical properties of cLL, the recombinant protein was expressed, affinity purified and characterized. Recombinant cLL was expressed as four differently sized peptides, which is most likely due to post-translational modification. Crosslinking of the protein led to the formation of two high-molecular weight products, indicating that cLL forms trimeric and possibly even multimeric subunits. cLL was shown to have lectin activity, preferentially binding to alpha-mannose in a calcium-dependent manner. Furthermore, cLL was shown to inhibit the haemagglutination-activity of human isolates of influenza A virus, subtype H3N2 and H1N1. These result show that cLL is a true C-type lectin with a very distinct sugar specificity, and that this chicken lectin could play an important role in innate immunity. 相似文献
85.
Luana Alves Dummer Fábio Pereira Leivas Leite Sylvia van Drunen Littel-van den Hurk 《Veterinary research》2014,45(1)
The viral envelope glycoprotein D from bovine herpesviruses 1 and 5 (BoHV-1 and -5), two important pathogens of cattle, is a major component of the virion and plays a critical role in the pathogenesis of herpesviruses. Glycoprotein D is essential for virus penetration into permissive cells and thus is a major target for virus neutralizing antibodies during infection. In view of its role in the induction of protective immunity, gD has been tested in new vaccine development strategies against both viruses. Subunit, DNA and vectored vaccine candidates have been developed using this glycoprotein as the primary antigen, demonstrating that gD has the capacity to induce robust virus neutralizing antibodies and strong cell-mediated immune responses, as well as protection from clinical symptoms, in target species. This review highlights the structural and functional characteristics of BoHV-1, BoHV-5 and where appropriate, Human herpesvirus gD, as well as its role in viral entry and interactions with host cell receptors. Furthermore, the interactions of gD with the host immune system are discussed. Finally, the application of this glycoprotein in new vaccine design is reviewed, taking its structural and functional characteristics into consideration. 相似文献
86.
Galuppo LD Simpson EL Greenman SL Dowd JP Ferraro GL Meagher DM 《Veterinary surgery : VS》2006,35(5):423-430
OBJECTIVE: To report clinical evaluation of headless compression screws for repair of metacarpal/metatarsal (MC/MT3) condylar fractures in horses. STUDY DESIGN: Retrospective case study. SAMPLE POPULATION: Racing Thoroughbreds (n=16) with nondisplaced lateral condylar fractures of MC/MT 3. METHODS: Medical records (1999-2004) of horses with nondisplaced longitudinal fractures of the lateral condyle of MC/MT3 were reviewed. Pre-operative variables retrieved were: patient age, gender, limb involvement, injury occurrence, fracture length, and width, evidence of palmar comminution and degenerative joint disease, number of pre-injury starts, and pre-injury earnings. Post-operative variables retrieved were: surgical complications, surgical time, number of race starts, and post-operative earnings. RESULTS: MC3 (n=11) and MT3 (5) nondisplaced longitudinal fractures of the lateral condyle were repaired with Acutrak Equine (AE) screws. Left front limb fractures were most common (8) followed by left hind (5) and right front (3). Nine fractures occurred during training and 7 during racing; 4 fractures had palmar comminution. No surgical complications occurred. Of 15 horses that returned to training, 11 (73%) raced 306+/-67 days after injury and had greater mean (+/-SD) post-injury earnings/start ($5290.00+/-$8124.00) than pre-injury ($4971.00+/-$2842.00). Screw removal was not required in any horse. CONCLUSION: The AE screw is a viable option for repair of nondisplaced lateral condylar MC/MT3 fractures in Thoroughbred racehorses. CLINICAL RELEVANCE: Adequate stability of nondisplaced lateral condylar fractures can be achieved with a headless tapered compression screw while avoiding impingement on the collateral ligaments and joint capsule of the fetlock joint. 相似文献
87.
Görig C Coenen RT Stades FC Djajadiningrat-Laanen SC Boevé MH 《American journal of veterinary research》2006,67(1):134-144
OBJECTIVE: To examine the practical aspects, accuracy, and reproducibility of 2 new automatic handheld tonometers in dogs and compare them with results for 2 established applanation tonometers. ANIMALS: 15 freshly enucleated canine eyes for manometric evaluation and 20 conscious research dogs, 20 client-owned dogs, and 12 dogs with acute glaucoma for clinical tonometry. PROCEDURE: Calibration curves were determined for all 4 tonometers on 15 enucleated canine eyes. Intraocular pressure (IOP) was measured with each tonometer consecutively in conscious dogs, with the MacKay-Marg applanation tonometer as the reference device. Measurements were repeated in 20 sedated dogs. An induction-impact tonometer was evaluated clinically on dogs with acute glaucoma. Additionally, measurements obtained by an experienced and an inexperienced examiner and with or without use of topical anesthesia were compared. RESULTS: The portable pneumatonometer was cumbersome and time-consuming. Compared with results for the reference applanation tonometer, and confirmed by manometry, the portable pneumatonometer increasingly underestimated actual IOP values with increasing IOP. The induction-impact tonometer provided accurate and reproducible measurement values. There was a significant strong correlation between the IOP values obtained by the 2 examiners (r2, 0.82) and also with or without topical anesthesia (r2, 0.86). In dogs with glaucoma, the fitted line comparing values for the reference applanation tonometer and induction-impact tonometer closely resembled an ideal 1:1 relationship. CONCLUSIONS AND CLINICAL RELEVANCE: Use of the portable pneumatonometer in dogs appears to have disadvantages. The induction-impact tonometer appears to provide a promising alternative to the use of applanation tonometers in dogs. 相似文献
88.
Rosado B García-Belenguer S León M Palacio J 《Veterinary journal (London, England : 1997)》2009,179(3):383-391
Dog bites in humans are a complex problem embracing public health and animal welfare. To prevent dog bites it is necessary to have comprehensive epidemiological data that allow the identification of associated risk patterns. This study was aimed at investigating the problem posed by dog bites in Spain. The epidemiology of medically attended dog bite-related incidents reported in Aragón was analysed from 1995 to 2004. Bite incidents were mostly associated with: (1) low-population areas (71.3/100,000 inhabitants); (2) males and children, particularly those aged 5–9; (3) single injuries directed to the head and neck area in children and to the extremities in adults; (4) young, male, medium to large, owned dogs that were known to the victim; (5) summer months, and (6) specific circumstances such as human interference with knocked down and fighting dogs. In the light of these risk patterns, a wide range of specific preventive measures could be proposed. 相似文献
89.
Microbiological baseline study of poultry slaughtered in provincially inspected abattoirs in Alberta, Canada 下载免费PDF全文
Valerie M. Bohaychuk Sylvia L. Checkley Gary E. Gensler Pablo Romero Barrios 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(2):173-178
Studies to determine baseline levels of microbial contaminants and foodborne bacterial pathogens are needed to evaluate the effectiveness of Hazard Analysis Critical Control Point (HACCP) programs, Good Manufacturing/Production Practices, and various interventions. In 2004 and 2005 poultry carcass rinses from provincially inspected abattoirs in Alberta, Canada, were tested to determine the levels of aerobic plate count bacteria, coliform bacteria, and generic Escherichia coli, the prevalence and levels of Campylobacter spp., and the prevalence of Salmonella spp. and Shiga toxin-producing E. coli (STEC). Samples were collected from 3 high volume and 62 low volume abbatoirs. All samples (1296) were positive for aerobic plate count bacteria, with 98.8% of samples having counts of 100 000 or less colony forming units (CFU)/cm2. Coliform bacteria were isolated from 99.7% of the 1296 carcasses and were recovered at levels of ≤ 1000 CFU/cm2 for 98.3% of the samples. Generic E. coli were recovered from 99.1% of the 1296 carcasses at levels of ≤ 1000 CFU/cm2 for 98.6% of the samples. Seventy five percent of 1234 samples that were tested for Campylobacter were positive; 37.5% of 1295 samples that were tested for Salmonella were positive; and only 2 of 1296 samples tested for STEC were positive (0.15%). 相似文献
90.
John A. Walsh Rachel L. Rusholme Sara L. Hughes Carol E. Jenner Judith M. Bambridge Derek J. Lydiate Sylvia K. Green 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(1):15-20
Pathotype-specific and broad-spectrum resistance to turnip mosaic virus (TuMV) have been identified in the diploid A genome brassica species Brassica rapa. The pathotype-specific resistance is effective against pathotype 1 isolates of TuMV, which are the most common in Europe. It is almost identical in its specificity to that of a mapped resistance gene (TuRB01) present in the A genome of the amphidiploid species Brassica napus. A mutant of a pathotype 1 isolate of TuMV (UK 1M) that is able to overcome TuRB01 also overcame the B. rapa resistance. This, combined with the fact that a single-nucleotide mutation in the cylindrical inclusion gene of TuMV that has been shown to induce a change from avirulence to virulence against TuRB01, had an identical effect on the B. rapa resistance, suggest that the two resistances are conditioned by the same gene. A second source of resistance in B. rapa prevented systemic spread of all TuMV isolates tested. A third source of resistance that appears to provide immunity to, or severely restrict replication of most isolates of TuMV has been characterised. This resistance source also prevented systemic spread of all TuMV isolates tested. Prior to this study, no resistance to pathotype 4 or pathotype 12 isolates of TuMV had ever been identified. For each of these three resistance sources, plant lines that are not segregating for some of the resistance phenotypes and that are presumably homozygous for the genes controlling these phenotypes have been generated. Strategies for further characterising and deploying these resistances in different Brassica species are described. 相似文献