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31.
Attempts were made to recover and serologically identify mycoplasmas from the lungs of 50 pigs with mycoplasmal pneumonia and from 50 lungs without gross evidence of pneumonia. Mycoplasma hyopneumoniae and M. hyorhinis were respectively cultured from 30% and 50% of pneumonic lungs and the former species was also recovered from 12% of non-pneumonic lungs. Three other isolates (one from pneumonic and two from non-pneumonic lungs) differed in colonial morphology from M. hyopneumoniae and M. hyorhinis. The viability of these isolates could not be maintained on subculture and they were not identified serologically. The indirect immunofluorescence test was found to be highly specific for the identification and differentiation of M. hyopneumoniae and M. hyorhinis.  相似文献   
32.
Mastitis caused by the colourless alga Prototheca zopfii was diagnosed in 17 of 120 cows in a dairy herd. Infection occurred in animals varying from 3-14 years old and was present in one to four quarters of each cow. Nine cases were associated with clinical mastitis characterised by the presence in milk of flakes or small clots. Somatic cell counts consistent with subclinical mastitis (>500 x 10(3) cells/ml) were recorded in five of the eight remaining cows. Histological examination of udder tissue showed the presence of granulomatous lesions associated with the presence of Prototheca. The problem was identified and controlled by repeated microbiological examination of milk samples from all lactating cows and immediate culling of infected animals. P. zopfii was also recovered from environmental water samples on this farm. It is suggested that infection may have occurred as a result of teat sores caused by trauma from a milking machine, and the tendency for cows to lay down on a race, the surface of which was sometimes flooded by drain water in which Prototheca were present.  相似文献   
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AIMS: To report on the long-term outcomes of hydraulic artificial urethral sphincter (HAUS) placement for the correction of urethral sphincter mechanism incompetence (USMI) in New Zealand dogs.

METHODS: Retrospective data were obtained from cases of dogs which had a HAUS placed after failed medical and/or surgical management of USMI between August 2012 and November 2016. Owner assessment of urinary incontinence was evaluated by an online survey in May 2017 using a visual analogue scale (0 being normal, 100 being severely affected) for the frequency, volume and severity of any straining to urinate, immediately prior to the placement of the HAUS and at the time of the survey. The number of days between surgery and the completion of survey were recorded.

RESULTS: Seven females and two male dogs, which were all desexed except for one female, were eligible for inclusion in the study. The period of follow-up following HAUS placement ranged from 206–1,685 days. Following HAUS placement, frequency and volume of urinary incontinence decreased for six dogs and were practically unchanged for three dogs. The median frequency score decreased from 70 to 13 and the volume score decreased from 73 to 12. There was no consistent change in the perceived degree of straining to urinate. Complications occurred in three dogs; one required repositioning of a dislodged injection port, one required management for haematuria and a hypoplastic bladder, and one required surgical removal of fibrous tissue around the HAUS cuff.

CONCLUSIONS AND CLINICAL RELEVENCE: HAUS placement was an effective method for the treatment of persistent USMI in most dogs and provided good clinical results based on owner assessment. The technique was associated with few complications and allowed successful long-term control of urinary incontinence without the need for medical management.  相似文献   

35.
Zoning restrictions and other land use regulations that may significantly impact natural resource-based industries traditionally have been the responsibility of local governments in the United States. This study uses a logistic regression model to estimate the influence of spatial and demographic factors on the probability that Georgia, Florida, and Louisiana counties adopt local regulations to improve water quality. The analysis identifies demographic and spatial factors that significantly influenced the probability a county would adopt local water quality regulations, spatially depicts which local regulations are most likely to be adopted, and maps the probability that a county would adopt the regulation.  相似文献   
36.
The relationship between open windspeed and windspeed reduction in shelter   总被引:3,自引:0,他引:3  
Windspeed reduction in shelter is generally expressed relatively and is usually assumed to be independent of open windspeed. The purpose of this study was to re-examine the relationship between open windspeed and windspeed reduction in shelter using windspeeds and wind directions measured for two windbreak systems at various distances from the windbreaks and with three windbreak porosities. Optical windbreak porosities were estimated from digitized color photographs using an intelligent (trainable) image processing program. Relative windspeed reduction in shelter was found to be related to the open windspeed. There existed a threshold windspeed at approximately 5 m s–1, below which relative windspeed reduction varied but generally decreased as the open windspeed increased. Above the threshold windspeed, open windspeed did not have an effect on relative windspeed reduction in the sheltered zone. Using the threshold windspeed reduction, the authors propose an index to evaluate the effectiveness of a windbreak for the overal windspeed protection.Published as Journal Series No. 10815 of the Agricultural Research Division, University of Nebraska.  相似文献   
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Infection of Poa pratensis leaf blades and callus tissue by Bipolaris sorokiniana increases the production of ethylene and ethane. The ethylene is responsible for most of the chlorosis that occurs during pathogenesis. The nonselective toxin(s) produced by B. sorokiniana is known to disrupt membranes and to damage chlorophyll, but it is not known whether it can induce an increase in ethylene or ethane. Research was initiated to determine the effect of a biologically-active extract of B. sorokiniana on the endogenous ethylene and ethane of intact P. pratensis leaf blades and on subsequent development of chlorosis. The extract did not increase endogenous ethylene of treated leaves, but it was associated with an increase in endogenous ethane between 24 and 96h after treatment. Chlorophyll loss occurred 96h after treatment and persisted for the duration of the study (168h). The chlorophyll content of treated leaf blades ranged from 72% to 80% of control leaf blades. The observations suggest that the extract of B. sorokiniana can induce chlorophyll loss from treated leaf blades independent of an increase in endogenous ethylene by directly damaging chloroplasts with a concurrent release of ethane. The ethane is believed to be a by-product of pathogenesis.  相似文献   
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The establishment of P. truncatus in Africa has highlighted the inherent weakness of phytosanitary measures against exotic pests. Consideration is given to the need for phytosanitary measures and how patterns of international trade affect phytosanitary control. To prevent the spread of pests such as P. truncatus, large grain shipments can be subject to stringent pest control procedures. However, a significant proportion of grain movement in Africa, both within countries and across borders, occurs informally by both illicit, commercial movement of multiple truckloads of grain and legally by individuals carrying headloads via bush paths or small parcels on public transport. Attempts to locate and inspect the small lots would be impractical. Some recommendations are given on how the spread of P. truncatus in large-scale international trade can be slowed but otherwise it is accepted that in the long-term the prevention of further spread of P. truncatus in Africa is wholly unrealistic.  相似文献   
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