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991.
Jose A. Estevez Alberto Martínez Andrés J. García Francisco Ceacero Enrique Gaspar-López Antonio Calatayud Laureano Gallego 《Acta theriologica》2009,54(3):235-242
Previous studies have suggested that antlers are costly bone structures whose mineral composition may change depending on
physiological and other factors. This study examined whether nutrition variation associated with deer management influences
antler mineral composition and structural characteristics of whole antler. Mineral distribution and bone structure were examined
in antlers from two groups of adult Iberian red deer Cervus elaphus hispanicus Hilzheimer, 1909. They were kept under different feeding regimes at an experimental deer farm and a game estate in southeastern
Spain. Protein and mineral contents differed between the diet of captive deer and that of deer in the wild. Significant differences
were found for Na, Mg, K and protein. Antler composition seems to reflect the diet, as antlers of deer differed in protein,
Na, Mg and K, but not in total mineral content, Ca, Fe or Zn. Thus, management conditions related to nutrition are reflected
on antler composition. 相似文献
992.
Andrei Daniel Mihalca Miloslav Jirků Patrick Kenyatta Malonza David Modrý 《Systematic parasitology》2009,74(3):219-223
Coprological examinations of eight Ruppell’s agamas Agama rueppelli (Vaillant) revealed the presence of a coccidium of the genus Isospora Schneider, 1881 that represents a previously undescribed species. Oöcysts of Isospora farahi n. sp. are spherical or subspherical, 29.1 (26–31) × 28.8 (26–31) μm, with a shape-index of 1.01 (1–1.07). An oöcyst residuum, polar granules and micropyle are absent. The oöcyst wall is bilayered, brownish and smooth, c. 1.5–2 μm thick. The sporocysts are oval, 16.6 (15–18) × 11.4 (11–12) μm, with a shape-index of 1.46 (1.25–1.64) and both Stieda and substieda bodies. A sporocyst residuum is present as medium-sized granules scattered irregularly among the sporozoites. The sporozoites are vermiform, with a large posterior spherical refractile body. Endogenous development is intranuclear in the epithelial cells of the small intestine. Sporulation is unknown, as oöcysts were recovered from the faeces. 相似文献
993.
Sophie Casteret Najat Chbab Jeanne Cambefort Corinne Augé-Gouillou Yves Bigot Florence Rouleux-Bonnin 《Molecular genetics and genomics : MGG》2009,282(5):531-546
Previous studies have shown that the transposase and the inverted terminal repeat (ITR) of the Mos1
mariner elements are suboptimal for transposition; and that hyperactive transposases and transposon with more efficient ITR configurations
can be obtained by rational molecular engineering. In an attempt to determine the extent to which this element is suboptimal
for transposition, we investigate here the impact of the three main DNA components on its transposition efficiency in bacteria
and in vitro. We found that combinations of natural and synthetic ITRs obtained by systematic evolution of ligands by exponential
enrichment did increase the transposition rate. We observed that when untranslated terminal regions were associated with their
respective natural ITRs, they acted as transposition enhancers, probably via the early transposition steps. Finally, we demonstrated
that the integrity of the Mos1 inner region was essential for transposition. These findings allowed us to propose prototypes of optimized Mos1 vectors, and to define the best sequence features of their associated marker cassettes. These vector prototypes were assayed
in HeLa cells, in which Mos1 vectors had so far been found to be inactive. The results obtained revealed that using these prototypes does not circumvent
this problem. However, such vectors can be expected to provide new tools for the use in genome engineering in systems such
as Caenorhabditis elegans in which Mos1 is very active. 相似文献
994.
Catecholamines (noradrenaline, NA; adrenaline, AD; dopamine, DA) influence the metabolic and cardiovascular responses to exercise.
However, changes in catecholamine metabolism during exercise are unclear. Plasma normetanephrine (NMET), metanephrine (MET)
and catecholamine responses to a laboratory-based model of games-type exercise were examined. Twelve healthy men completed
a resting control trial and a trial consisting of ten 6 s cycle ergometer sprints interspersed with 30 s recovery, in randomised
order. Resting and post-sprint venous blood samples were taken. Plasma NA and AD increased after each sprint but DA was unaltered.
Plasma nephrines increased significantly from sprint 4 onwards with peak NMET increasing 60% to 0.76 ± 0.19 nmol l−1 and MET 230% to 0.37 ± 0.16 nmol l−1 from resting values (P < 0.05). The results demonstrate increased catecholamine metabolism via elevated catechol-O-methyl transferase activity during intermittent sprinting. The results may aid regulation of the metabolic and cardiovascular
responses to exercise by maintaining tissue adrenoceptor sensitivity to circulating catecholamines. 相似文献
995.
Juneyoung Lee Hyun Joo Hong Jin-Kyoung Kim Jae-Sam Hwang Yangmee Kim Dong Gun Lee 《Molecules and cells》2009,28(5):473-477
Previously, the 9-mer analog peptides, 9Pbw2 and 9Pbw4, were designed based on a defensin-like peptide, protaetiamycine isolated
from Protaetia brevitarsis. In this study, antifungal effects of the analog peptides were investigated. The antifungal susceptibility testing exhibited
that 9Pbw4 contained more potent antifungal activities than 9Pbw2. A PI influx assay confirmed the effects of the analog peptides
and demonstrated that the peptides exerted their activity by a membrane-active mechanism, in an energy-independent manner.
As the noteworthy potency of 9Pbw4, the mechanism(s) of 9Pbw4 were further investigated. The membrane studies, using rhodamine-labeled
giant unilamellar vesicle (GUV) and fluorescein isothiocyanate (FITC)-dextran loaded liposome, suggested that the membrane-active
mechanism of 9Pbw4 could have originated from the poreforming action and the radii of pores was presumed to be anywhere from
1.8 nm to 3.3 nm. These results were confirmed by 3D-flow cytometric contour-plot analysis. The present study suggests a potential
of 9Pbw4 as a novel antifungal peptide. 相似文献
996.
This study investigated the enolization and racemization reactions of glucose and fructose on heating with amino acid enantiomers
and the formation of melanoidins as a result of the Maillard reaction. The study measured reducing sugars and L- and D- amino acids using HPLC as an index for the amount of enolization of the sugars and isomerization of the amino acids. Additionally,
the absorption of melanoidins was measured at different wavelengths (420, 450, 470, 490 nm); the UV–Vis spectra and the extinction
coefficient were determined for the formation of melanoidins. Melanoidins were, rather arbitrarily, defined by a high-molecular-weight
(HMW) if it was above a lower limit of 12.4 kDa, which was the nominal cut-off value in the dialysis system used. A remarkable
enolization reaction of the sugars was observed in the course of the Maillard reaction. Especially, in the Fru/D-Asn model system, the degree of sugar enolization was more than in the other model systems. All of the FDAA (1-fluoro-2,
4-dinitrophenyl-5-L-alanine amide) amino acids were separated by TLC. The racemization of the amino acids was higher in the fructose-amino acids
systems. Isomer formation was the highest in the Fru/D-Asn system. The L- and D- isomers showed different absorptions in the UV–Vis spectra, although these had similar shapes. The absorption of the melanoidins
formed from glucose was higher than that formed from fructose. In particular, the sugar–asparagine system showed different
characteristics according to the L- and D-isomers. The differences in the extinction coefficients of the melanoidins was significant (P < 0.05), except for the sugar–lysine system. 相似文献
997.
Hui Hu Ling Tao Yabin Wang Liying Chen Jihong Yang Hanzhong Wang 《Biotechnology letters》2009,31(11):1685-1693
The immunogenicity of SARS-CoV nucleocapsid DNA vaccine and the immunoregulatory activity of interleukin-2 (IL-2) were investigated.
DNA vaccine plasmids, pcDNA-N and pcDNA-IL2, were constructed and inoculated into BALB/c mice with or without pcDNA-IL2 by
intramuscular injection. Cellular and humoral immune responses were assessed by indirect ELISA, lymphocyte proliferation assays,
ELISPOT and FACS. The nucleocapsid DNA vaccine had good immunogenicity and can induce specific humoral and cellular immunity
in BALB/c mice, while IL-2 plays an immunoadjuvant role and enhances specific immune responses. This study provides a frame
of reference for the design of DNA vaccines against SARS-CoV. 相似文献
998.
999.
Modelling and predicting the potential habitat and future range expansion of invasive species can help managers to mitigate
the impact of such species. Because habitat suitability and the colonization process are key determinants of range expansion,
inferences drawn from invasion patterns should be based on both attributes. To predict the potential habitat and expansion
rate of the invasive tree Bischofia javanica on Hahajima Island, we used simultaneous models of habitat and dispersal to estimate the effect of environment and dispersal
from the source population on the current distribution. We compared the fit and the estimated magnitudes of the environment
and dispersal effects in the simultaneous models with those in habitat suitability and colonization kernel models. The values
of Akaike’s information criterion for the simultaneous models were better than those of the habitat suitability and colonization
kernel models, indicating that the current distribution of Bischofia was determined by both environment and dispersal. The simultaneous models predicted that the potential habitat of Bischofia would be larger than that predicted by the habitat suitability model. The potential habitat distribution and future invasion
predicted by the simultaneous models will contribute to the development of specific landscape-scale management plans to control
this invasive species. 相似文献
1000.
Nicolas Bonnet Kara N. Standley Estelle N. Bianchi Vincent Stadelmann Michelangelo Foti Simon J. Conway Serge L. Ferrari 《The Journal of biological chemistry》2009,284(51):35939-35950
Periostin (gene Postn) is a secreted extracellular matrix protein involved in cell recruitment and adhesion and plays an important role in odontogenesis. In bone, periostin is preferentially expressed in the periosteum, but its functional significance remains unclear. We investigated Postn−/− mice and their wild type littermates to elucidate the role of periostin in the skeletal response to moderate physical activity and direct axial compression of the tibia. Furthermore, we administered a sclerostin-blocking antibody to these mice in order to demonstrate the influence of sustained Sost expression in their altered bone phenotypes. Cancellous and cortical bone microarchitecture as well as bending strength were altered in Postn−/− compared with Postn+/+ mice. Exercise and axial compression both significantly increased bone mineral density and trabecular and cortical microarchitecture as well as biomechanical properties of the long bones in Postn+/+ mice by increasing the bone formation activity, particularly at the periosteum. These changes correlated with an increase of periostin expression and a consecutive decrease of Sost in the stimulated bones. In contrast, mechanical stimuli had no effect on the skeletal properties of Postn−/− mice, where base-line expression of Sost levels were higher than Postn+/+ and remained unchanged following axial compression. In turn, the concomitant injection of sclerostin-blocking antibody rescued the bone biomechanical response in Postn−/− mice. Taken together, these results indicate that the matricellular periostin protein is required for Sost inhibition and thereby plays an important role in the determination of bone mass and microstructural in response to loading. 相似文献