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A simple method using tissue extraction of Copper (Cu) in 8M nitric acid for 45 minutes at 100 degrees C, followed by sample dilution and Cu quantitation by flame atomic absorption spectroscopy is described. The detection limit of the method is 16 micromol Cu/kg liver. The mean recovery of added Cu was 100.4%. This method for liver copper analysis correlated well with a method using nitric/perchloric acid digestion and atomic absorption spectroscopy (r2 = .986) and is faster, less expensive and less hazardous.  相似文献   
64.
In determining the effect of prior feeding of antimicrobials on subsequent antimicrobial therapy in induced colibacillosis of piglets with Escherichia coli serotype O62 (Dey et al., 1977), study groups in one trial developed spontaneous colibacillosis due to a different Escherichia coli serotype O147. This paper reports the results and conclusion drawn from this outbreak.

Both groups, irrespective of antimicrobial feeding, developed disease, and the attack rates for the groups were not significantly different. Neither mortality nor the clinical course of illness in animals without therapy changed significantly as a function of antimicrobial feeding. The antimicrobial feeding had no effect on the therapeutic efficacies of chloramphenicol or chlortetracycline utilized for treating the disease. Chloramphenicol therapy was more effective in terminating the disease.  相似文献   

65.
Tropical Animal Health and Production - The low potency of genetic immunization has to date impeded development of commercial vaccines against major infectious diseases. The aim of this study was...  相似文献   
66.
The objectives of this study were to determine (i) if in subtropical goats that gave birth during mid‐December, the exposition to an artificial long‐day photoperiod consisting in only 14 hr of light per day can increase the milk yield and (ii) to test whether these females can respond to the male effect at the end of the prolonged photoperiodic treatment. In experiment 1, 17 lactating goats were maintained under natural short days (control group), while another 22 goats were maintained under artificial long days (treated group) consisting in 14 hr light and 10 hr darkness starting at day 10 of lactation. The continuous exposition to an artificial long‐day photoperiod produced an increase in the milk yield level during the first 110 days of lactation (time × treatment interaction; = .01), while none of the milk components were modified due to the photoperiodic treatment (> .05). In experiment 2, all control and treated anovulatory goats were submitted to the male effect using photostimulated males. All females showed oestrous behaviour within the first 10 days that were in contact with males (100% in both groups; > .05). Thus, the latency to onset of oestrus did not differ between females from control (58.2 ± 3.0 hr) and treated (62 ± 4.6 hr) groups. Male exposition provoked ovulation independently if females were previously under long days or natural photoperiod (96 vs 100%, respectively; = .79). It was concluded that exposure to 14 hr of light per day in subtropical goats that gave birth in late autumn stimulates milk yield without preventing the ovulation in response to the male effect at the end of the prolonged photoperiodic treatment.  相似文献   
67.
DNA barcoding represents an objective tool for fast species identification, especially for taxa for which morphological identification is difficult. One current limitation of barcoding is the lack of reference sequences for many groups. While many European and North American countries have started their own barcoding initiatives to generate complete local inventories and databases, such efforts are sparse for African, Asian and South American countries, despite their high biodiversity and comparably poorly explored faunas. Therefore, it is important to start local barcoding efforts in such countries. In this study we performed DNA barcoding for the band-winged grasshoppers of the Biskra province in Algeria, a region of high diversity for this taxon. All specimens were identified morphologically and then barcoded. We generated a total of 47 sequences of the COI gene for 22 morphologically identified species of Oedipodinae, many of which were sequenced for the first time. We present the data in a phylogenetic tree, which suggests monophyly for most genera, but rejects it for Sphingonotus and Vosseleriana. Statistical species delimitation worked well for most genera, except those within the Sphingonotini, likely because these have radiated rather recently. Together with data sourced from the literature we used our new data set to generate an updated list of band-winged grasshoppers for the region. Several species are recorded for the region and for the country for the first time. One species appears to be new to science. Furthermore, we found geographic variation within several more widespread species for which data from other countries were present. We consider the new data as an important resource for future faunistic, ecological and biodiversity studies and point out the importance of local (taxon-specific) barcoding studies.  相似文献   
68.
Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales), an entomopathogenic fungus, was introduced through seed inoculation with spore suspension as an endophyte in white jute (Corchorus capsularis L.), a bast fiber crop. Out of nine B. bassiana strains, seven, viz., ITCC 6063, ITCC 4512, ITCC 4563, ITCC 5562, ITCC 4796, ITCC 5408 and ITCC 4705, became established as endophytes. The endophytic colonization was initially detected by cultivation on selective medium. Colonization was confirmed by polymerase chain reaction (PCR) using sequence characterized amplified region (SCAR) marker. Endophytic B. bassiana strains colonized in leaves of all the plants grown from treated seeds. However, the colonization frequency varied among the strains. The highest colonization frequency (70.09%) was recorded in ITCC 6063 followed by ITCC 5562 (67.67%) and ITCC 5408 (64.17%); ITCC 4512 exhibited the lowest (42.54%) colonization. ITCC 4925 and ITCC 4644 did not show any colonization. Endophytic colonization of B. bassiana reduced stem weevil infestation under pot culture. ITCC 5408 and ITCC 6063 were found most efficient, with only 10.44% and 14.06% infested plants, respectively.  相似文献   
69.
Present work was undertaken to screen some drought tolerant indigenous aromatic rice cultivars (IARCs), commonly cultivated in West Bengal, India, based on their capacity to produce osmolytes, redox-sensitive phenolic acids and flavonoids, as contrivances for redox-regulation under drought stress. Polyethylene glycol induced post imbibitional dehydration stress mediated changes in redox regulatory properties of the germinating seeds of the four IARCs (Jamainadu, Tulaipanji, Sitabhog, Badshabhog), which were assessed in terms of changes in prooxidant accumulation (in-situ localization of reactive oxygen species (ROS) by confocal microscopy, DCFDA (2′,7′-dichlorofluorescin diacetate) oxidation, O2 and H2O2 accumulation), cumulative antioxidative defense (radical scavenging property and total thiol content), ROS scavenging phenolic acids (gallic acid, protocatechuic acid, gentisic acid, para-hydroxy benzoic acid, chlorogenic acid, caffeic acid, syringic acid, salicylic acid, sinapic acid and p-coumaric acid) and flavonoids (catechin, naringin, rutin, quercetin, kaempferol, myricetin and apigenin). The capability of germinating seeds to accumulate osmolytes (like glycinebetaine, proline, soluble carbohydrates and K+ ion) and polyphenolic compounds was also correlated with their corresponding redox status and redox biomarkers (conjugated diene, hydroperoxide, thiobarbituric acid reactive substances and free carbonyl content) produced under the same conditions. The results in general showed that accumulation of osmolytes along with the redox-sensitive phenolics and flavonoids conferred the ability to maintain the redox homeostasis under drought stress for the tolerant IARCs (Badshabhog and Tulaipanji).  相似文献   
70.
Asia is now the largest potato-producing region of the world and late blight, caused by Phytophthora infestans, is the most important pathogen limiting production. This review documents, in both the historical and the current context, the population structure of P. infestans in the major areas of potato production in Asia. Information from diverse sources regarding the stated or inferred clonal pathogen lineages present, population changes, and possible migration routes of the pathogen into the countries of this region have been reviewed to aid researchers and those involved in managing late blight in Asia. The single most important factor for population change and resultant epidemics in this region has been found to be migration of pathogen genotypes from Europe and the Americas. Reducing the impact of such migration in the future will necessitate putting in place improved phytosanitary measures. To achieve this, data sharing using global networks such as AsiaBlight and EuroBlight is imperative.  相似文献   
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