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991.
This paper studies the effect of an integral suspension of Lepidium latifolium on experimental induced prostate hyperplasia, in rats. Oral treatment with 0.86 mg kg(-1) day(-1) for 6 months, significantly reduced prostate size and volume in castrated rats where the hyperplasia were induced by steroid treatment.  相似文献   
992.
Ovine enzootic abortion (OEA) is caused by Chlamydophila abortus, an intracellular bacterium which acts by infecting the placenta, causing abortion in the last term of gestation. The main prevention strategy against OEA is the vaccination of flocks. An effective vaccine against C. abortus must induce a Th1-like specific immune response, which is characterized by the early production of IFN-gamma and the activation of CD8(+)T cells. Moreover, vaccine effectiveness could be modulated by the functioning of the innate immunity. The purpose of this study was to ascertain how polymorphonuclear neutrophils (PMNs) and NK cells might influence vaccine-induced protection. The live attenuated 1B vaccine and two inactivated experimental vaccines, adjuvated with aluminium hydroxide (AH) or QS-21 (QS), were used in PMN-depleted or NK cell-depleted mice. For PMN depletion, RB6-8C5 monoclonal antibody, which recognizes GR1(+) receptors (Robben, P.M., LaRegina, M., Kuziel, W.A., Sibley, L.D. 2005. Recruitment of Gr-1(+) monocytes is essential for control of acute toxoplasmosis. The Journal of Experimental Medicine 201, 1761-1769.) was used, while for NK cell-depletion the anti-asialo GM1 polyclonal antibody was used. The depletion of PMNs caused 100% mortality in non-vaccinated mice (NV) and 60% mortality in the AH-vaccinated mice by day 10 p.i., while both groups showed a significant increase in their bacterial burden in the liver by day 4 p.i. The depletion of NK cells caused mortality only in the NV group (50% by day 10 p.i.), although this group and the 1B vaccinated mice showed an increased bacterial burden in the liver at day 4 p.i. Our results suggest that the importance of PMNs in inactivated vaccines depends on the adjuvant chosen. The results also demonstrated that the importance of NK cells is greater in live vaccines than in inactivated vaccines.  相似文献   
993.
PCR method was applied for the qualitative identification of chicken (Gallus gallus), turkey (Meleagris gallipavo), duck (Anas platyrhynchos x Cairina muschata), and goose (Anser anser) tissues in feed-stuffs, on an individual basis. The assay uses oligonucleotide primers that are specific for each avian species, targeting the 12S rRNA mitochondrial gene. The primers designed generated amplicons of 95, 122, 64, and 98 bp length for chicken, turkey, duck, and goose, respectively. The specificity of the primers was tested against 29 animal species including mammals, birds, and fish, as well as 8 plant species. Analysis of experimental feedstuffs demonstrated the detection of each target species in the range of 0.1 to 100%. The performance of this method was not affected by prolonged heat-treatment (up to 133 degrees C for 20 min at 300 kPa), and consequently, it could be very useful for the accurate identification of tissues from these 4 avian species in products submitted to denaturing technologies, for which other methods cannot be applied.  相似文献   
994.
First detection of canine parvovirus type 2c in South America   总被引:8,自引:0,他引:8  
Since its sudden emergence in the early 1970s, canine parvovirus type-2 (CPV-2) has been evolving through the generation of novel genetic and antigenic variants (CPV-2a/b/c and a number of additional mutations) that are unevenly distributed throughout the world. In order to develop strategies to control the spread of these variants and to understand virus evolution is fundamental to genotype field isolates from different geographic locations. In the present paper we have examined 25 isolates of CPV from clinical samples of Uruguayan dogs collected during year 2006. A fragment of the VP2 gene of the virus was analyzed using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) and DNA sequence analysis. Out of the 25 isolates analyzed, only one was characterized as CPV-2a and 24 were characterized as CPV-2c, indicating that this type is currently the prevalent field CPV circulating in Uruguay. This is the first report of CPV-2c in the American continent and it also represents the highest frequency of this type observed in a dog population so far. Its presence in South American supports the assumption that CPV-2c is reaching a worldwide distribution as occurred with 2a/2b antigenic types.  相似文献   
995.
The prevalence of gastrointestinal parasites in dogs was studied in the province of Córdoba (southern Spain), with special attention to those parasites that can be transmitted to man. The experiment was completed with the examination of soil samples from public parks and city gardens. The study was carried out over a population of 1800 animals entered in the Control Animal Centre (CECA) by coprological methods, and within this group, 300 dogs were sacrificed and necropsied. The prevalence of any intestinal parasitic infection was 71.33%. The following parasites of the gastrointestinal tract were recorded: Isospora canis (22%), Isospora (Cystoisospora) spp. (10.22%), Sarcocystis (2.5%), Hammondia/Neospora (1.94%), Giardia canis (1%), Dipylidium caninum (13.2%), Taenia hydatigena (7.66%), Taenia pisiformis (4%), Uncinaria stenocephala (33.27%), Toxascaris leonina (14.94%), Toxocara canis (17.72%) and Trichuris vulpis (1.66%). Related to public health, it is important to point out the presence of T. canis only in puppies younger than one year and Uncinaria, more frequent in adult dogs. Soil samples of parks revealed the presence of eggs of Toxocara, and it suggests the existence of real risk for human infection.  相似文献   
996.
The aim of the study was to determine the presence of swine hepatitis E virus (HEV) RNA and antibodies in postweaning multisystemic wasting syndrome-affected (n=114) and non-affected (n=46) pigs and the possible association with hepatitis lesions. Forty-four pigs were RT-PCR positive (28.2%); 25 of them were PMWS cases, while 19 were non-PMWS pigs. In both groups, HEV RT-PCR results were associated with hepatitis (OR=5.61 for PMWS-affected pigs and OR=5.17 for non-PMWS affected pigs; p=0.01). No interaction was detected in a logistic regression between PMWS occurrence and HEV infection for the development of hepatitis lesions. Seropositivity to HEV was more likely to occur in pigs with hepatitis (51.9%) compared to pigs without hepatitis (36.1%; p=0.03). Significant differences in optical densities were notices comparing the lesional stage of pigs (p=0.009). While pigs with slight or moderate hepatitis were seropositive, pigs with more severe lesions were seronegative to HEV. These results indicate that swine HEV infection can be a significant contributor to the development of moderate hepatitis in pigs regardless of the PMWS status.  相似文献   
997.
A survey was conducted on 172 farms belonging to the same company in order to ascertain the biosecurity measures applied and the importance that farmers attributed to each measure. A questionnaire about general data, the opinions of farmers about biosecurity measures, and a detailed checklist of the biosecurity measures actually applied on the farm was completed for each one of the participating farms. Opinion data were initially analysed by means of a cluster analysis (multidimensional scaling method); then, a logistic regression was used to analyse the relationship between the perceptions of the farmer and the measures applied on the farm. In general, farmers implemented measures to reduce risks of contamination from people and animals other than pigs. In contrast, biosecurity measures related to replacement stock were not applied as often. On average, the farmers scored the biosecurity on their own farms as 6.7 on a scale of 0-10. The most important measures, according to the farmers' perceptions, were the availability of a sanitary ford, a fence around the farm, the restriction of visits and vehicles, using bird-proof nets in windows, having changing facilities, applying quarantines, and the use of other measures related to replacement stock. The perception of a given measure was strongly influenced by the measures actually applied on the farm. Thus, for example, those who did not have a sanitary ford highlighted the importance of disinfecting vehicles while those who had one neglected this type of disinfection. In conclusion, knowledge of the relationships between perceptions and measures taken is important in developing effective biosecurity strategies on pig farms.  相似文献   
998.
  • 1. Marine protected areas (MPAs) are expected to function simultaneously as biological conservation and fisheries management tools, but empirical evidence linking biodiversity conservation with fisheries benefits is scarce. Around the Medes Islands marine reserve (Spain, NW Mediterranean) patterns of fish catch diversity, catch (CPUE) and income (IPUE) were assessed and the economic value of diversity for local fisheries was explored by combining a Geographic Information System (GIS) analysis with geostatistics.
  • 2. Catch data were derived from the trammel net fleet operating around the MPA to gain information on species diversity, functional diversity, functional redundancy, CPUE and IPUE.
  • 3. Results revealed significant impact of both the fishing prohibition in the MPA and the presence of seagrass beds on diversity metrics, catch and income. Clear differences in functional redundancy in fish assemblages were found within the study area, indicating greater resilience of the fish assemblage against fishing pressure or human impact close to the MPA (?2 km). In contrast, fish assemblages beyond 2 km of the MPA border are more vulnerable to disturbance. High values of diversity, CPUE and IPUE overlapped close to the MPA border and close to seagrass beds.
  • 4. The spatial approach developed suggests that, in addition to the more commonly studied effect of density‐dependent spillover of adult fish, increased levels of ecological diversity and economic diversity can also result in fisheries benefits of an MPA. Hence, the fishing regulations in and around the Medes Islands marine reserve have shown that biological conservation and fisheries benefits can be complementary in the long‐term, which should be considered in future policies for MPAs or MPA networks.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
999.
1000.
Shrimp aquaculture effluents were bioremediated in a two‐phase system (System A) using the black clam Chione fluctifraga and the benthic microalgae Navicula sp., and then reused to farm whiteleg shrimp Litopenaeus vannamei. In the experimental design, Systems B and C had an identical structure as System A, but no clams or microalgae were added. System B received the same shrimp effluents while System C received only estuarine water. Shrimp raw effluents had a poor water quality. System A improved the water quality by decreasing the concentrations of total nitrogen, total ammonia nitrogen (TAN), nitrites, nitrates, phosphates, total suspended solids (TSS) and organic suspended solids (OSS). System B also decreased the concentration of TAN, TSS and OSS via sedimentation, but the effect was less pronounced than that observed in System A. Shrimp reared in the bioremediated effluents (System A) had better production (3166 kg ha?1) and higher survival (89.2%) than those reared in effluents from Systems B (2610 kg ha?1, 75.1%) and C (2874 kg ha?1, 82.1%). It is concluded that the bioremediation system was moderately efficient and the bioremediated effluents were suitable to farm L. vannamei.  相似文献   
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