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991.
Santiago Nava Atilio J. Mangold Mariano Mastropaolo José M. Venzal Elena B. Oscherov Alberto A. Guglielmone 《Systematic parasitology》2009,73(3):161-174
All parasitic stages of Amblyomma boeroi n. sp. (Acari: Ixodidae) are described here from Catagonus wagneri (Rusconi) in Argentina. The diagnostic characters for the male are a combination of orbited eyes, a 2/2 dental formula, coxa
IV considerably larger than coxae I–III and with a long, sickle-shaped, medially directed spur arising from its internal margin,
a scutum which is light grey to very pale ivory in colour, and the absence of a postanal groove. The diagnostic characters
for the females are a combination of orbited eyes, a central pair and two marginal pairs of short, coarse notal setae, a 2/2
dental formula, and the absence of a postanal groove. The nymph has short palpi and a 2/2 dental formula arranged in 6 rows,
its eyes are convex and orbited, and it has no postanal groove. The dorsally rectangular basis capituli of the larva, its bulging eyes and slightly sinuous posterior scutal margin all serve to distinguish it from the larva of
other species of the genus. The principal host for all parasitic stages is C. wagneri (Artiodactyla: Tayassuidae). Phylogenetically A. boeroi appears to represent an independent lineage within Amblyomma Koch, 1844. 相似文献
992.
993.
Célia Regina Moreira Lanza Carlos Alberto de Souza Costa Maysa Furlan Alberto Alécio Josimeri Hebling 《Cell biology and toxicology》2009,25(6):533-543
Objective
To evaluated the transdentinal diffusion and subsequent cytotoxicity of self-etching adhesives on odontoblast-like cells. 相似文献994.
Ana Navarro Alberto Boveris Manuel J. Bndez María Jesús Snchez-Pino Carmen Gmez Gerard Muntan Isidro Ferrer 《Free radical biology & medicine》2009,46(12):1574-1580
Frontal cortex samples from frozen human brains were used to assess tissue respiration; content of mitochondria; mitochondrial oxygen uptake; activity of respiratory complexes and of mitochondrial nitric oxide synthase (mtNOS); content of cytochromes a, b, and c; oxidative damage (protein carbonyls and TBARS); and expression of Mn-SOD in patients with Parkinson disease (PD) and with dementia with Lewy bodies (DLB) in comparison with those of normal healthy controls. Brain cortex and mitochondrial O2 uptake and complex I activity were significantly lower in PD and DLB, whereas mtNOS activity, cytochrome content, expression of Mn-SOD, mitochondrial mass, and oxidative damage were significantly higher in the frontal cortex in PD and DLB. The decreases in tissue and mitochondrial O2 uptake and in complex I activity are considered the consequences of mitochondrial oxidative damage. The increases in mtNOS activity and in mitochondrial mass are interpreted as an adaptive response of the frontal cortex that involves increased NO signaling for mitochondrial biogenesis. The adaptive response would partially compensate for mitochondrial dysfunction in these neurodegenerative diseases and would afford a human evolutionary response to shortage of ATP in the frontal cortex. 相似文献
995.
Cervellati C Franzoni L Squerzanti M Bergamini CM Spinozzi F Mariani P Lanzara V Spisni A 《Amino acids》2009,36(4):633-641
Activation of tissue transglutaminase by calcium involves a conformational change which allows exposition of the active site
to the substrate via movements of domains 3 and 4 that lead to an increase of the inter-domain distance. The inhibitor GTP
counteracts these changes. Here we investigate the possible existence of non-native conformational states still compatible
with the enzyme activity produced by chemical and thermal perturbations. The results indicate that chemical denaturation is
reversible at low guanidine concentrations but irreversible at high concentrations of guanidine. Indeed, at low guanidine
concentrations tissue TG-ase exists in a non-native state which is still affected by the ligands as in the native form. In
contrast, thermal unfolding is always irreversible, with aggregation and protein self-crosslinkage in the presence of calcium.
DSC thermograms of the native protein in the absence of ligands consist of two partly overlapped transitions, which weaken
in the presence of calcium and merge together and strengthen in the presence of GTP. Overall, the present work shows, for
the first time, the reversible denaturation of a TG-ase isoenzyme and suggests the possibility that also in in vivo, the enzyme
may acquire non-native conformations relevant to its patho-physiological functions. 相似文献
996.
Alberto Martínez Chandima S. K. Rajapakse Dalanda Jalloh Cula Dautriche Roberto A. Sánchez-Delgado 《Journal of biological inorganic chemistry》2009,14(6):863-871
We have measured water/n-octanol partition coefficients, pK
a values, heme binding constants, and heme aggregation inhibition activity of a series of ruthenium–π-arene–chloroquine (CQ) complexes recently reported to be active against CQ-resistant strains of Plasmodium falciparum. Measurements of heme aggregation inhibition activity of the metal complexes near water/n-octanol interfaces qualitatively predict their superior antiplasmodial action against resistant parasites, in relation to
CQ; we conclude that this modified method may be a better predictor of antimalarial potency than standard tests in aqueous
acidic buffer. Some interesting tendencies emerge from our data, indicating that the antiplasmodial activity is related to
a balance of effects associated with the lipophilicity, basicity, and structural details of the compounds studied.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Daniele Colembergue da Cunha Jeferson Avila Souza Luiz Alberto Oliveira Rocha Jorge Alberto Vieira Costa 《World journal of microbiology & biotechnology》2009,25(12):2173-2178
The design of a modular bioreactor for solid state fermentation is a promising development because it keeps the homogeneity
of the bed at optimal levels. This study determines the optimum geometry of elementary modules of hexahedral bioreactors subjected
to constant volume. The bioreactors have a square section and do not need an external cooling system, because the optimization
limits the temperature of the bed to 35°C. The geometric optimization followed the Constructal principle of minimum heat resistance.
The numerical simulations take into account the following parameters: inlet air temperature and velocity, and module volume.
Once the elementary module has been selected, the total volume of the bioreactor can be calculated. 相似文献
998.
Adriano Pereira Paglia Gustavo Alberto B. Fonseca 《Biodiversity and Conservation》2009,18(13):3563-3577
Threatened species assessments are one of the tools used to evaluate the degree of human impact on biodiversity, particularly
in the assignment of extinction probabilities to individual species. Heavily altered habitats or biomes harbor a high proportion
of the threatened species that have been assessed globally—80% of all of threatened species in IUCN’s Red List owe their poor
status at least partly to the loss of habitat. Some taxonomic groups, however, may be well represented in the Red Lists either
because they are naturally more sensitive to the most pervasive threats, or simply because they have been better studied.
Here we look at the threat patterns on a temporal scale of Brazilian animal species included in the IUCN Red List, evaluating
the hypotheses that directions of changes in red list status can be explained by the increase in scientific knowledge or by
actual changes in threat factors. We analyzed changes in patterns of threatened vertebrates in IUCN’s list between 2002 and
2006. During that period, 120 species changed their status. 42 of these changes referred to inclusions and 78 to changes of
threat category. For the latter group, 23 had their status upgraded to categories of higher threat, and 55 downgraded to others
of lower threat. Most of the downgrades were caused by increase in scientific knowledge, while most of the upgrades resulted
from the deterioration of the environmental conditions. 相似文献
999.
Alfonso Fernández-álvarez Alberto Elías-Villalobos José I. Ibeas 《The Plant cell》2009,21(10):3397-3412
In Saccharomyces cerevisiae, the PMT, KRE2/MNT1, and MNN1 mannosyltransferase protein families catalyze the steps of the O-mannosylation pathway, sequentially adding mannoses to target proteins. We have identified members of all three families and analyzed their roles in pathogenesis of the maize smut fungus Ustilago maydis. Furthermore, we have shown that PMT4, one of the three PMT family members in U. maydis, is essential for tumor formation in Zea mays. Significantly, PMT4 seems to be required only for pathogenesis and is dispensable for other aspects of the U. maydis life cycle. We subsequently show that the deletion of pmt4 results in a strong reduction in the frequency of appressorium formation, with the few appressoria that do form lacking the capacity to penetrate the plant cuticle. Our findings suggest that the O-mannosylation pathway plays a key role in the posttranslational modification of proteins involved in the pathogenic development of U. maydis. The fact that PMT homologs are not found in plants may open new avenues for the development of fungal control strategies. Moreover, the discovery of a highly specific requirement for a single O-mannosyltransferase should aid in the identification of the proteins directly involved in fungal plant penetration, thus leading to a better understanding of plant–fungi interactions. 相似文献
1000.
Genetic mapping and annotation of genomic microsatellites isolated from globe artichoke 总被引:1,自引:0,他引:1
Alberto Acquadro Sergio Lanteri Davide Scaglione Paul Arens Ben Vosman Ezio Portis 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(8):1573-1587
Cynara cardunculus includes three taxa, the globe artichoke (subsp. scolymus L. Hegi), the cultivated cardoon (var. altilis) and their progenitor, the wild cardoon (var. sylvestris). Globe artichoke is an important component of the Mediterranean rural economy, but its improvement through breeding has
been rather limited and its genome organization remains largely unexplored. Here, we report the isolation of 61 new microsatellite
loci which amplified a total of 208 alleles in a panel of 22 C. cardunculus genotypes. Of these, 51 were informative for linkage analysis and 39 were used to increase marker density in the available
globe artichoke genetic maps. Sequence analysis of the 22 loci associated with genes showed that 9 are located within coding
sequence, with the repetitive domain probably being involved in DNA binding or in protein–protein interactions. The expression
of the genes associated with 9 of the 22 microsatellite loci was demonstrated by RT-PCR. 相似文献