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31.
Epoxysesquithujene, a new sesquiterpene epoxide has been characterized in the essential oil of Valeriana hardwickii var. hardwickii on the basis of chemical reactions and extensive NMR data. Fourteen other terpenoids have also been identified on the basis of GC-MS.  相似文献   
32.
Pasteurella multocida is a pathogenic, Gram-negative bacterium that is commonly found as normal flora in nasopharynx of variety of wild and domestic animals. Numerous virulence factors have been described for P. multocida isolates which include adherence and colonization factors, iron-regulated and acquisition proteins, extracellular enzymes such as neuraminidase, lipopolysaccharide (LPS), capsule and a variety of outer membrane proteins (Omp). OmpA has a significant role in stabilizing the cell envelope structure by providing physical linkage between the outer membrane & peptidoglycan. It has been shown to mediate P. multocida -host cells interaction via heparin and/or fibronectin binding and therefore act as an important invasive molecule which could determine the final outcome of initial infection. Comparative nucleotide sequence analysis of ompA gene of P. multocida has revealed that despite extensive genetic diversity in ompA of P. multocida, most sequences could be classified into two major allele classes namely ompA allele (I) and allele (II). The P. multocida recovered from nasal cavity of bovine and belonging to two ompA classes were tested for their differential virulence. In vitro pathogenicity studies on Madin Darby Bovine Kidney (MDBK) cell line employing adhesion and invasion assays indicated that P. multocida strain with ompA (I) is more invasive than P. multocida strain with ompA (II). In vivo studies in mice further reiterated that the isolates harbouring ompA(I) were comparatively more virulent to isolates harbouring ompA (II).  相似文献   
33.
Whole genome comparisons identified introgression from archaic to modern humans. Our analysis of highly polymorphic human leukocyte antigen (HLA) class I, vital immune system components subject to strong balancing selection, shows how modern humans acquired the HLA-B*73 allele in west Asia through admixture with archaic humans called Denisovans, a likely sister group to the Neandertals. Virtual genotyping of Denisovan and Neandertal genomes identified archaic HLA haplotypes carrying functionally distinctive alleles that have introgressed into modern Eurasian and Oceanian populations. These alleles, of which several encode unique or strong ligands for natural killer cell receptors, now represent more than half the HLA alleles of modern Eurasians and also appear to have been later introduced into Africans. Thus, adaptive introgression of archaic alleles has significantly shaped modern human immune systems.  相似文献   
34.
To facilitate recovery through captive breeding and foster-parenting programs of the endangered whooping crane, one of two eggs was removed from 62% of nests in Wood Buffalo National Park during 1967-1996. Egg removals were justified because cranes usually rear a single chick; the other dies to siblicide or predation. Concerns exist that the wild population might have recovered even faster if nests had not been disturbed. Here we show, contrary to expectation, that removing one of two eggs from a whooping crane nest actually increases the probability of nest success, and this effect is highly correlated with the dynamics of predators in the nesting area. These results beg the question: why do whooping cranes lay two eggs? We attribute two-egg clutches to occasional “good years” in which both chicks survive, compensating for higher mortality in two-egg broods. Egg removal has benefited conservation allowing establishment of several captive flocks, supporting reintroduction of two new populations, and reducing the variance in reproductive success of the wild flock thereby minimizing extinction risk.  相似文献   
35.
The photosynthesis, shoot formation, leaf area development and dry matter production were examined in control and de-eared plants of T. monococcum var. G 1372and T. aestivum var. Sonalika. The removal of ears decreased the diurnal maintenance of photosynthesis and consequently, the dry matter production in Sonalika but not in G 1372. There was a considerable growth of alternative sinks such as shoots and roots when ear sinks were removed. This alternative sink capacity of de-eared plants seemed to have compensated for limited sink demand of ears in G 1372but could not entirely compensate for the more efficient grain sink in Sonalika. The diploid wheat produced more dry matter than the hexaploid wheat in the pre-ear emergence period and less in the post-ear emergence period. In the preear emergence period, the difference in dry matter appeared to be mostly because of the difference in duration to ear emergence. During the post-ear emergence period, the lower dry matter in G 1372seemed to be owing to a rapid decrease in photosynthesis rate after anthesis because of the lower sink capacity of its grains.  相似文献   
36.
Seed morphometric characters and oil content were studied in multiple-use plant, Calophyllum inophyllum L. of two countries, Australia (southern hemisphere) and Sri Lanka (northern hemisphere). Seven provenances were selected which included three from northern Australia and four from Sri Lanka. Twelve Candidate plus trees (CPTs) each were selected from 2 to 3 different locations within each provenance based on the morphometric and qualitative traits (GBH > 100 cm). Seed collection in both hemispheres was carried out from May to August 2008. Calophyllum inophyllum L. provenances showed a distinct hemisphere variation in their seed-related characters and oil content. All provenances differed significantly (P < 0.05) with one another in seed length. Seeds from Anuradhapura, Sri Lanka and seeds from Cardwell Australia recorded the highest (≈57%) and the lowest oil (≈31%) content respectively. Strong correlations were found between seed morphometric characters. Relatively weaker correlations were found between seed morphometric characters and oil content. Variations in seed-related characters were largely attributed by the provenance contribution which shows the significance of the effect of genetic variability on above mentioned seed related characters.  相似文献   
37.
Mean individual fatty acid concentration among differentspecies of the family Cruciferae are not similar because of the presence ofdifferent kind of significant relationship among the individual fatty acids.Brassica napus L., Sinapis alba L.,Raphanus caudatus L.f. Raphanus sativusL. and B. nigra (L.) Koch arecomparatively low erucic acid (<40%) containing species. Crambeabyssinica Hochst. ex. R. E. Fries collections gave as high as 60%erucic acid. Low erucic acid concentration was found associated with thepresence of high level of palmitic and oleic acid concentrations. Erucic acidconcentrations were found varied within the range of 42 to 57% among thecollections of Brassica rapa L. and B.carinata A. Braun. All the collections ofB. nigra (L.) Koch were found to havehigher proportion of linoleic acid than the corresponding oleic acidconcentration. Linolenic acid concentrations of B.nigra (L.) Koch was also higher in comparison to otherspecies of the Cruciferae. Raphanus collections were foundto contain higher levels of total saturated fatty acids as well as eicosenoicacid. Oil content of the total collections under present study did not show anysignificant relationship either with linolenic acid or with erucic acidconcentration. But significant positive relationship was observed between totaloil and erucic acid level within the collections of B.juncea Czern. & Coss. Similarly significant negativecorrelation was observed between total oil and linolenic acid content inBrassica rapa L. ssp. trilocularis (Roxb.) Hanelt, yellow sarson.  相似文献   
38.
The present investigation was aimed to analyze influence of earthworm culture on nutritive status, microbial population, and enzymatic activities of composts prepared by utilizing different plant wastes. Vermicomposts were prepared from different types of leaves litter of horticulture and forest plant species by modified vermicomposting process at a farm unit. Initial thermophilic decomposition of waste load using cow‐dung slurry was done in the separate beds. The culture of Eisenia fetida was used for vermicomposting in specially designed vermibeds at the farm unit. The physico‐chemical characteristics, enzyme activities (oxido‐reductases and hydrolases), and microbial population (bacteria, fungi, free‐living nitrogen‐fixing bacteria, actinomycetes, Bacillus, Pseudomonas, phosphate‐solubilizing bacteria and fungi) of vermicomposts were found significantly higher (p < 0.05) than those of control (without earthworm inoculum). The study quantified significant contributions of earthworm culture to physico‐chemical, enzymatic, and microbiological properties of vermicompost and confirmed superior fertilization potential of vermicompost for organic farming. The agronomic utility of vermicompost was assessed on yellow mustard plant in a pot experiment. Pot soil was amended with different ratios (5%, 10%, 20%) of vermicompost and normal compost (without earthworm inoculum). Effects of these amendments on the growth of Brassica comprestis L. were studied. The significant differences (p < 0.05) in the growth of plant were observed among vermicompost‐, compost‐amended soil, and control. Vermicompost increased the root and shoot lengths, numbers of branches and leaves per plant, fresh and dry weights per plant, numbers of pods and flowers, and biochemical properties of plant leaf significantly, especially in 20% amendment. These results proved better fertilization potential of vermicompost over non‐earthworm‐inoculated compost.  相似文献   
39.
Phytoparasitica - Thrips are economically important pests of crops and vectors of viral diseases worldwide. Invasion and outbreak of thrips have recently caused havoc in agricultural and...  相似文献   
40.
Three weaning foods were formulated from locally available cereals and pulses such as rice (Oryza sativa), kangini (Setaria italica), sanwak (Echinochloa frumentacea), green gram (Vigna radiata) and jaggery. Cereals and pulses were mixed in the proportion of 7:3. Nutrient composition of developed weaning foods was within range prescribed by Indian Standard Institute and was found to be acceptable. Roasting was the processing technique employed in developing weaning foods which resulted in significant increase in HC1-extractable minerals, an index of their bioavailability to humans. The higher HC1-extractability of the minerals may be ascribed to the decreased phytic acid in the processed home made weaning foods.  相似文献   
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