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1.
Serum antibody (virus neutralisation, complement fixation, IgM and IgG) responses to equine herpesvirus-1 (EHV-1) infection were measured in six foals which were initially free from EHV-1 and EHV-4 infection and maternally-derived antibodies. Following primary infection, high titres of virus neutralisation and complement fixation antibodies were detectable against EHV-1, however, corresponding antibody levels against EHV-4 were low or inapparent, although the two viruses share a number of cross-reactive epitopes. In addition, following the primary infection with EHV-1, IgM levels increased before those of IgG, virus neutralisation and complement fixation antibodies, peaked sooner and thereafter declined. Stimulation of IgM levels was observed on secondary infection with EHV-1 given 61 days later. In contrast, IgG, virus neutralisation and complement fixation antibodies following primary infection were more sustained and no increase in their levels was observed on secondary infection. No consistent changes in IgM or IgG levels were seen after administration of dexamethasone to reactivate latent virus. 相似文献
2.
Bacterial pathogens of Greenshell™ mussel (GSM) larvae can cause batch losses during hatchery production. Twenty-two isolates were screened using a larval bioassay. Two strains were identified as potential pathogens. Phenotypic identification of these strains revealed two non-reactive Gram-negative, oxidase positive rods. Sequencing of the 16S rRNA gene identified Vibrio splendidus and a V. coralliilyticus/neptunius -like isolate as pathogens of GSM larvae, with an ability to cause 83% and 75% larval mortality in vitro , respectively, at a concentration of 102 CFU mL−1 . Histopathology indicated that the route of infection was via the digestive system. Using healthy larvae as target hosts, Koch's postulates were confirmed for the two isolates. This is the first report on pathogens of GSM larvae. 相似文献
3.
Total carbon and nitrogen abundances were determined by using combustion-gas chromatographic techlniques. Weighited mean analyses for butlk fines were 225 and 140 ppm total carbon and 150 anid 100 ppm total nitrogen. Total carbon in fine breccia was 230 ppm; in coarse breccia, 100 ppmn; in fine-grained rock, 70 ppm; and in mediumn-grained rock, 64 ppm. The finest sieved fraction had the highest carbon content. Total nitrogen in fine breccia was 125 ppm; in coarse breccia, 100 ppm; in fine-grained rock, 115 ppm; and in medium-grained rock, 30 ppm. The total carbon and nitrogen finies appeat to be mixtuires of indigenous lunar material togetheer with meteoritic and solar wind components. 相似文献
4.
K L Gibson R T vanEe R D Pechman 《Journal of the American Veterinary Medical Association》1991,198(5):886-890
Complications associated with femoral capital physeal (CP) fractures in 34 dogs were evaluated. Fractures were surgically repaired, using divergent K-wires or lag screws; radiographic follow-up was available for 21 CP fractures. In all cases, radiographic abnormalities such as degenerative joint disease and resorption of the femoral neck and/or head were seen. Changes were more severe when fracture occurred at an early age. For 4 of 21 dogs (20%), femoral head and neck excision was performed because of complications associated with CP fracture repair. Prognosis for femoral CP fractures is guarded, although affected dogs should be able to function as pets. 相似文献
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6.
Margo E Chase-Topping Ian Handel Bartlomiej M Bankowski Nicholas D Juleff Debi Gibson Sarah J Cox Miriam A Windsor Elizabeth Reid Claudia Doel Richard Howey Paul V Barnett Mark EJ Woolhouse Bryan Charleston 《Veterinary research》2013,44(1):46
The control of foot-and-mouth disease virus (FMDV) outbreaks in non-endemic countries relies on the rapid detection and removal of infected animals. In this paper we use the observed relationship between the onset of clinical signs and direct contact transmission of FMDV to identify predictors for the onset of clinical signs and identify possible approaches to preclinical screening in the field. Threshold levels for various virological and immunological variables were determined using Receiver Operating Characteristic (ROC) curve analysis and then tested using generalized linear mixed models to determine their ability to predict the onset of clinical signs. In addition, concordance statistics between qualitative real time PCR test results and virus isolation results were evaluated. For the majority of animals (71%), the onset of clinical signs occurred 3–4 days post infection. The onset of clinical signs was associated with high levels of virus in the blood, oropharyngeal fluid and nasal fluid. Virus is first detectable in the oropharyngeal fluid, but detection of virus in the blood and nasal fluid may also be good candidates for preclinical indicators. Detection of virus in the air was also significantly associated with transmission. This study is the first to identify statistically significant indicators of infectiousness for FMDV at defined time periods during disease progression in a natural host species. Identifying factors associated with infectiousness will advance our understanding of transmission mechanisms and refine intra-herd and inter-herd disease transmission models. 相似文献
7.
OBJECTIVE: The National Diet and Nutrition Surveys (NDNS) are a series of government-funded surveys of food intake, nutrient intake and nutritional status of individuals, undertaken to support nutritional policy and risk assessment. This paper summarises a review that considered the extent to which NDNS met the needs of users and suggested options for the future. The Food Standards Agency has since progressed favoured options. This paper aims to help others wishing to obtain this type of information within their own populations. DESIGN: A detailed questionnaire was used to probe use of data and gather opinions from users, producers and managers of the NDNS. It asked about general information needs from NDNS and changes that might be made. This was followed by a two-day workshop which included discussion of the main issues and the generation of 19 possible future options for consideration by the Agency. RESULTS: Options to improve effectiveness included methods to prioritise breadth and depth of coverage and possible ways of improving response and compliance. Strategies to make surveys more efficient and timely, such as adopting a rolling programme, disaggregating survey components, integrating with other studies and improving data access, were also suggested. A rolling programme, in which data are collected continuously, was the favoured option to address some of the concerns and a strategy is now in place to achieve this. CONCLUSIONS: There is widespread support for the NDNS from its users. There is no alternative source for such high-quality data on food and nutrient consumption and nutritional status and physical measurements in the same individuals. Useful information, such as the potential value of using a rolling programme from the outset, can be gained from this British experience by others wishing to measure food and nutrient intakes and status in their own populations. 相似文献
8.
Jéssica Lauanda Stirle;Jordana Emannuelly Ferreira Matias;Gabriel Ribeiro Mendes;Valéria Fonseca Moscardini;Jader Braga Maia;JP Michaud;Pablo Costa Gontijo; 《Pest management science》2024,80(12):6535-6544
Lepidopteran pest control in agriculture has become heavily dependent on cultivars that express Bacillus thuringiensis (Bt) toxins as ‘plant-incorporated protectants’. However, populations of Spodoptera frugiperda (Smith) in Brazil appear resistant to the Bt traits currently available in commercial soybean cultivars. 相似文献
9.
In Accelerated Recurrent Selection (ARS) schemes, selection is based on the predicted performance of progeny families, estimated as the average of the parental families. These schemes can halve cycle time compared to simple recurrent selection methods. They also have a lower requirement for evaluation of families in yield trials, although they do require more seed production. ARS therefore provides options in cycle time, effective population size, response to selection and cost which have not been available before. Example schemes are compared by computer simulation with truncation selection and with optimal family selection, where contributions of families to the next generation are optimised to give the maximum response to selection at a specified effective population size. In many circumstances, ARS schemes compare favourably. Difficulties in combining estimates of selection intensity and of effective population size when comparing the merits of different breeding schemes are discussed. It is suggested that unless one is interested in response to selection over periods greater than 50 years, the weight given to effective population size in ranking different schemes should be small. 相似文献
10.
Heald AH Sharma R Anderson SG Vyas A Siddals K Patel J Bhatnagar D Prabharkaran D Rudenski A Hughes E Durrington P Gibson JM Cruickshank JK 《Public health nutrition》2005,8(6):620-627
BACKGROUND: The insulin-like growth factor (IGF) system is implicated in the pathogenesis of diabetes and cardiovascular disease. OBJECTIVE: We report the effects of total energy intake on the IGF system in two populations with markedly different dietary macronutrient intake and cardiovascular event rate. DESIGN, SUBJECTS AND SETTING: Dietary macronutrient intake was measured in a specific Gujarati migrant community in Sandwell, UK (n=205) compared with people still resident in the same villages of origin in India (n=246). Fasting IGF-I, IGF-binding protein (IGFBP)-1 and IGFBP-3, insulin and glucose (0 and 2-hour) were measured. RESULTS: Total energy and total fat intake were higher in UK migrants, as were IGFBP-3 and IGF-I (mean (95% confidence interval): 145.9 (138.1-153.6) vs. 100.9 (94.6-107.3) ng ml(-1); F=76.6, P<0.001). IGFBP-1 was lower in UK migrants (29.5 (25.9-33.0) vs. 56.5 (50.6-62.5) microg l(-1); F=48.4, P<0.001). At both sites, IGF-I correlated positively with total energy (Spearman's rho=0.45, P<0.001) and total fat (rho=0.44, P<0.001) as did IGFBP-3 with total energy (rho=0.21, P<0.05) and fat (rho=0.26, P<0.001). Conversely, in Indian Gujaratis, IGFBP-1 fell with increasing total energy (rho=-0.27, P<0.001) and fat intake (rho=-0.26, P<0.01) but not in UK Gujaratis. Multiple linear regression modelling showed that increasing quartiles of fat intake were associated with higher IGF-I (beta=0.42, P=0.007) independent of age, body mass index, plasma insulin, fatty acids and 2-hour glucose. CONCLUSION: In these genetically similar groups, migration to the UK and adoption of a different diet is associated with marked changes in the IGF system, suggesting that environmental factors profoundly modulate serum concentrations and actions of IGFs. 相似文献