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271.
The high specific richness of the vascular flora of the National Park of ‘Alta Murgia’ (Apulia, Italy) has been originated by a long co-evolutionary process of biophysical and anthropic systems. Natural disturbances on the one hand and the anthropic on the other, as years go by, in their mutual interaction, have created suitable conditions for the coexistence of a high number of taxa. Following an ecological and floristic survey of grasslands of Alta Murgia, many species of great phyto-geographical value or, however, threatened by genetic erosion and/or extinction together with other plants traditionally employed by man as officinal and for food and non-food purposes, were recorded. The ecological conditions that allow the persistence of these plant communities must be searched in the delicate equilibrium established among the natural dynamics and the set of disturbance regime, for great part due to the traditional land use. The actual social and economic transformations of the area, without safeguarding programmes to be carried out according to sustainability criteria, can produce a serious biodiversity decline. Starting from the ‘sustainable use’ definition of the CBD, the present paper deals with some focal points to realize the sustainable management of the biodiversity of the Park of Alta Murgia.  相似文献   
272.
Isatis tinctoria L. is a biennial species which was cultivated in Europe until the 18th century to produce indigo, a pigment used for dyestuffs. Today there is renewed interest in this ancient crop because of a market demand for natural dyes. Cultivation of the species appears to be particularly suitable for marginal areas. Information about the evolutionary and genetic patterns of I. tinctoria is needed if varieties or to be developed in future breeding programs. The aim of this study was to assess the genetic variation and similarity levels among and within natural populations of I. tinctoria from Europe and central Asia. Fifteen populations were used to carry out the genetic analyses with AFLP and SAMPL molecular markers. Data collected were analysed by the UPGMA method and were used to perform AMOVA. The results are consistent with the hypothesis that the crop originated in an eastern centre of origin and moved westward giving rise to a gene pool that is quite different from the original. The wide within-population variation revealed by this study suggests that effective breeding work to develop varieties suitable for marginal environments can be carried out easily.  相似文献   
273.
Nitric oxide was found to trigger mitochondrial biogenesis in cells as diverse as brown adipocytes and 3T3-L1, U937, and HeLa cells. This effect of nitric oxide was dependent on guanosine 3',5'-monophosphate (cGMP) and was mediated by the induction of peroxisome proliferator-activated receptor gamma coactivator 1alpha, a master regulator of mitochondrial biogenesis. Moreover, the mitochondrial biogenesis induced by exposure to cold was markedly reduced in brown adipose tissue of endothelial nitric oxide synthase null-mutant (eNOS-/-) mice, which had a reduced metabolic rate and accelerated weight gain as compared to wild-type mice. Thus, a nitric oxide-cGMP-dependent pathway controls mitochondrial biogenesis and body energy balance.  相似文献   
274.
Sponge-associated microorganisms are able to assemble the complex machinery for the production of secondary metabolites such as polyketides, the most important class of marine natural products from a drug discovery perspective. A comprehensive overview of polyketide biosynthetic genes of the sponge Plakortis halichondrioides and its symbionts was obtained in the present study by massively parallel 454 pyrosequencing of complex and heterogeneous PCR (Polymerase Chain Reaction) products amplified from the metagenomic DNA of a specimen of P. halichondrioides collected in the Caribbean Sea. This was accompanied by a survey of the bacterial diversity within the sponge. In line with previous studies, sequences belonging to supA and swfA, two widespread sponge-specific groups of polyketide synthase (PKS) genes were dominant. While they have been previously reported as belonging to Poribacteria (a novel bacterial phylum found exclusively in sponges), re-examination of current genomic sequencing data showed supA and swfA not to be present in the poribacterial genome. Several non-supA, non-swfA type-I PKS fragments were also identified. A significant portion of these fragments resembled type-I PKSs from protists, suggesting that bacteria may not be the only source of polyketides from P. halichondrioides, and that protistan PKSs should receive further investigation as a source of novel polyketides.  相似文献   
275.
In recent years many sterols with unusual structures and promising biological profiles have been identified from marine sources. Here we report the isolation of a series of 24-alkylated-hydroxysteroids from the soft coral Sinularia kavarattiensis, acting as pregnane X receptor (PXR) modulators. Starting from this scaffold a number of derivatives were prepared and evaluated for their ability to activate the PXR by assessing transactivation and quantifying gene expression. Our study reveals that ergost-5-en-3β-ol (4) induces PXR transactivation in HepG2 cells and stimulates the expression of the PXR target gene CYP3A4. To shed light on the molecular basis of the interaction between these ligands and PXR, we investigated, through docking simulations, the binding mechanism of the most potent compound of the series, 4, to the PXR. Our findings provide useful functional and structural information to guide further investigations and drug design.  相似文献   
276.
The deep-water rose shrimp, Parapenaeus longirostris, is a target species of the Mediterranean fisheries mostly caught by trawlers offshore, processed, and frozen on board. The effects of thawing on shrimp muscle exudate collected at 0, 1, 2, 3 days after thawing were investigated. In total, 70-kDa heat-shock protein (Hsp70), alpha (α)-enolase, and manganese superoxide dismutase (Mn-SOD) were selected as metabolic and stress-related proteins and analyzed by immunoblotting on exudates. Data were compared for the amount of exudates collected and the pH values. Among the investigated proteins, only the Hsp70 levels showed a decrease related to the post-thawing period and correlated with both the significant increase of the exudate amount and the pH values. These data strongly suggest the potential use of Hsp70 as an early predictive biomarker for quality of the P. longirostris shrimp after thawing.  相似文献   
277.

Purpose

The aim of this research was to determine the vinasse irrigation effects on the arbuscular mycorrhizal fungi (AMF) population (total spore abundance (TSA), richness, relative abundance, and diversity indices) and soil parameters and nutrients at high doses. The irrigation of soil with vinasses derived from sugarcane, beet, or alcohol production is a common practice around the world. Little is known about how this affects the AMF community and soil nutrients.

Materials and methods

The spider plant (Chlorophytum comosum, (Thunb.) Jacques), a mycorrhizable plant, was used to investigate the effect of 4 months of frequent vinasse irrigation (0, 25, 50, 75, and 100% vinasse concentration) on AMF and soil characteristics, e.g., electrical conductivity (EC), pH, mineral N, available P, Na+, K+, Ca2+, and Mg2+.

Results and discussion

The vinasse irrigation decreased the TSA, AMF richness and diversity after 4 months, regardless of vinasse concentration. The vinasse irrigation did not acidify the soil, but the EC, mineral N and available P increased. The biomass of C. comosum decreased (77–81%) after vinasse irrigation for 4 months.

Conclusions

Frequent irrigation with vinasse at concentrations ≥50% increases EC, K+, Na+, Mg2+, Ca2+ and available P in the soil, and decreases the amount of AMF spores, richness and diversity, which is not desirable in agricultural soils.
  相似文献   
278.
Ditylenchus dipsaci is a species complex including diploid and polyploid individuals. The onion race of D. dipsaci is a sensu stricto group and has a wide range of host spectrum. Identification of the D. dipsaci onion race is difficult using morphological and morphometrical methods. Species specific primers are mostly used in molecular approaches for identification of D. dipsaci populations. Fifty one morphologically selected Ditylenchus spp. populations from onion production areas in Turkey were subjected to molecular identification using four D. dipsaci species specific primer sets (PF1-PR1, PF2-PR2, DdpS1-rDNA2, DitNF1- rDNA2, H05-H06) targeting 5.8S and 18S rDNA, ITS1 and flanking ITS regions. Thirty nine percent of the nematode samples were positive with four primers tested, while four of the nematode samples gave specific bands with H05-H06 primers. Ditylenchus dipsaci sensu stricto was identified with specific primer sets in Adana, Hatay, Tekirdag, Bursa, Aksaray, Karaman, Eskisehir and Ankara provinces in Mediterranean, Trace, Aegean and Central Regions in Turkey.  相似文献   
279.
280.
When an accidentally introduced pest establishes in the invaded area, native natural enemies may adapt to the new host. A decade after the accidental introduction of the brown marmorated stink bug, Halyomorpha halys, in Europe, two generalist native egg parasitoids, the eupelmid Anastatus bifasciatus and the encyrtid Ooencyrtus telenomicida, have been recorded from this invasive agricultural pest in the field. Both species are able to complete development to the adult stage within the new host. Trissolcus basalis (Platygastridae = Scelionidae), which is not associated with H. halys in the field, was reared from freeze-killed sentinel eggs placed on soybean plants in central Italy. We tested in a Y-tube olfactometer the behavioural responses of these egg parasitoids to volatiles from H. halys adults and from Vicia faba plants attacked by H. halys. Both A. bifasciatus and O. telenomicida positively responded to adult H. halys male volatiles and to H. halys-induced plant volatiles, indicating ability to exploit cues associated with the new host for egg location, whereas T. basalis only reacted to female volatiles. A. bifasciatus and O. telenomicida are generalist egg parasitoids, showing a much wider host range when compared to T. basalis. On the other hand, platygastrid egg parasitoids from the native area of H. halys, considered for classical biological control, may be too risky due to the possibility of attacking non-target species, including predaceous stink bugs. Therefore, indigenous A. bifasciatus and O. telenomicida are presently under evaluation for augmentative biological control of H. halys in Europe.  相似文献   
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