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31.
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Three- to six-week-old hamsters were orally inoculated with broths containing one of the following cultures: Campylobacter mucosalis; C. hyointestinalis; C. coli; C. jejuni, all of porcine proliferative enteritis origin, or else C. jejuni of hamster origin. Hamsters given the last of those organisms were shown to have colonisation of their intestines by C. jejuni and 36 of 40 developed an acute enteritis. Mild hyperplasia of enterocytes in ileal crypts was evident in one hamster 2 days after it was given C. coli. No other lesions were detected. Further 3-week-old hamsters were orally inoculated with homogenised intestinal mucosa collected from 4 pigs (A-D) affected by proliferative enteritis. Lesions of proliferative enteritis were detected in 7 of 41 hamsters necropsied 10-21 days after being dosed with mucosas B or D. Marked hyperplasia of ileal enterocytes, associated with numerous intracellular Campylobacter-like organisms, were invariably detected in experimentally affected hamsters. No particular Campylobacter sp. was consistently isolated. None of the controls had demonstrable lesions. The results suggested that cross-species transmission of proliferative enteritis was possible from pigs to hamsters. Therefore a common initiating or aetiological agent may be present. No specific organism was identified as filling this role by inoculation of hamsters with pure cultures. 相似文献
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Elaine T. Lawson Jesse S. Ayivor Fidelia Ohemeng Yaa Ntiamoa‐Baidu 《Zoonoses and public health》2019,66(1):108-116
Zoonotic pathogens cause an estimated 70% of emerging and re‐emerging infectious diseases in humans, affecting various aspects of human development on a global scale. The significance of bats as a source of emerging infectious diseases is being progressively appreciated. This study was undertaken post‐Ebola virus disease in West Africa and assessed the public health implications of human–bat interactions by exploring the reasons for contact between humans and bats, as well as reported actions taken upon experiencing bat bites or scratches. The paper highlights the nuances of human–bat interactions, stressing zoonotic disease risk awareness as well as the sources of information. The study used questionnaires to solicit information from 788 respondents in five communities with significant bat populations. We show that bat consumption was one of the main reasons for human–bat interactions. More men across the various communities ate bat meat. Only a small number of respondents (4.4%) reported being bitten by a bat, and 6.1% had been scratched by a bat. More than 21% had come into direct contact with bat blood. An even lower number went to the hospital after been bitten or scratched by bats. There was little knowledge on post‐exposure management. The most common places human–bat interactions occurred were at home and on farms. Seventy‐three per cent of the respondents believed that bats carried diseases, with Ebola virus disease being the most mentioned. Respondents indicated that the way they interacted with bats had not changed, even though they believed bats carried diseases and 46% stated that they had not changed the way they interacted with bats over the last two years. Apart from providing information on avoiding bites and scratches, a more holistic framework is needed to reduce human–bat interactions. The paper recommends a comprehensive and coordinated approach to optimizing an effective response to a potential bat‐borne zoonotic disease spillover. 相似文献
35.
Murray D. Jelinski John R. Campbell Jonathan M. Naylor Karen L. Lawson Dena Derkzen 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(6):621-629
The objective of this study was to generate demographic data on veterinarians working in western Canada. A sample of 551 veterinarians was randomly selected from a population of 2474 veterinarians employed in western Canada, 425 (77.1%) of whom responded to the survey. The respondents were evenly split between males (53.1%) and females (46.9%). More than half (58.0%) of the private practitioners practised exclusively on companion animals (small animals and horses), while 2.9% devoted 100% of their time to food animals. There were 351 respondents who had had ≥ 2 employers since graduation; 80% of those who had begun their careers in companion animal (CA) practice had remained in this type of practice, while 54.3% of those who had begun their careers in mixed animal practice had switched to CA practice. Analyses of wage and workload data from 85 full-time veterinary employees showed that CA practitioners worked the fewest hours/week (47.0), had the least number of evenings on-call/month (3.7), and earned the highest hourly wage ($35.79) as compared with non-CA practitioners. 相似文献
36.
Lawrence E. V. Lawson Francis C. Brentu Eric W. Cornelius Kwadwo A. Oduro María E. Sedano Antonio Vicent 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):167-180
Pseudocercospora fruit and leaf spot (PFLS) of citrus, caused by Pseudocercospora angolensis, was recently described in Ghana and has spread in most citrus-growing areas of the country. A survey of PFLS incidence was conducted in the Eastern Region. Orchards were georeferenced and data on altitude, annual mean temperature, and annual precipitation were obtained from the WorldClim database. Fruit drop due to PFLS and other pests and diseases was evaluated in three orchards. Field efficacies of 4-week, 6-week and 8-week schedules with carbendazim + mancozeb were evaluated in the major and minor fruit production seasons. Ordinal logistic regression and generalized linear models were fitted in each case according to the nature of the data and possible overdispersion. Disease incidence in the sweet orange orchards surveyed was 25–100 %, with higher values in higher altitude areas exposed to lower temperatures and higher rainfall. PFLS was the main problem causing yield losses, associated with 84–87 % of fruit dropped on the orchard floor. PFLS severity on shoots and incidence on fruit 12 weeks after full bloom was significantly reduced by all fungicide schedules evaluated. The effects of fungicides on PFLS severity in fruit at harvest were not substantial because of intense fruit drop. The 8-week schedule showed the lowest effectiveness in reducing fruit drop and thus the 6-week schedule is preferred. Further research is needed for an integrated management of PFLS in Ghana. 相似文献
37.
Widespread divergence between incipient Anopheles gambiae species revealed by whole genome sequences
Lawniczak MK Emrich SJ Holloway AK Regier AP Olson M White B Redmond S Fulton L Appelbaum E Godfrey J Farmer C Chinwalla A Yang SP Minx P Nelson J Kyung K Walenz BP Garcia-Hernandez E Aguiar M Viswanathan LD Rogers YH Strausberg RL Saski CA Lawson D Collins FH Kafatos FC Christophides GK Clifton SW Kirkness EF Besansky NJ 《Science (New York, N.Y.)》2010,330(6003):512-514
The Afrotropical mosquito Anopheles gambiae sensu stricto, a major vector of malaria, is currently undergoing speciation into the M and S molecular forms. These forms have diverged in larval ecology and reproductive behavior through unknown genetic mechanisms, despite considerable levels of hybridization. Previous genome-wide scans using gene-based microarrays uncovered divergence between M and S that was largely confined to gene-poor pericentromeric regions, prompting a speciation-with-ongoing-gene-flow model that implicated only about 3% of the genome near centromeres in the speciation process. Here, based on the complete M and S genome sequences, we report widespread and heterogeneous genomic divergence inconsistent with appreciable levels of interform gene flow, suggesting a more advanced speciation process and greater challenges to identify genes critical to initiating that process. 相似文献
38.
39.
Clutton RE Schoeffmann G Chesnil M Gregson R Reed F Lawson H Eddleston M 《The Veterinary record》2011,169(17):440
High fractional concentrations of inspired oxygen (FiO(2)) delivered over prolonged periods produce characteristic histological changes in the lungs and airway of exposed animals. Modern medical anaesthetic machines are adapted to deliver medical air (FiO(2)=0.21) for the purpose of reducing FiO(2); anaesthetic machines designed for the veterinary market have not been so adapted. Two inexpensive modifications that allow medical air to be added to the gas flow from veterinary anaesthetic machines are described. The advantages and disadvantages of each modification are discussed. 相似文献
40.
Innocent Y.D. Lawson Kikuo Muramatsu Ichio Nioh 《Soil Science and Plant Nutrition》2013,59(4):721-728
Abstract A field experiment was conducted to examine the effects of two organic materials (Bark and Tenporon composts) on the growth, nodulation and nitrogen fixation (measured as acetylene-reducing activity) of soybean plants (Glycine max L.) under acid and saline conditions. These organic materials were incorporated into acid and saline (induced by irrigating the soil with a NaCl solution) soils at 4% rate of application. These composts tended to improve nodule formation in soybean under acid and saline conditions, especially in the plants treated with Bark compost. Acetylene-reducing activity was significantly (P<0.05) increased by these composts under acid condition. These composts also tended to improve shoot growth under acid and saline conditions, presumably due to the improvement of the soil moisture status of the soils and nutrient uptake. These results suggest that the growth of soybean could be improved by the application of organic matter under acid and saline conditions. 相似文献