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991.
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
992.
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
993.
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
994.
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
995.
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
996.
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
997.
998.
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
999.
Tomomi Tadokoro Masahiko Ikekita Tosifusa Toda Hiroko Ito Takeshi Sato Ryunosuke Nakatani Yu Hamaguchi Kiyoshi Furukawa 《The Journal of biological chemistry》2009,284(51):35556-35563
β-Galactose residues on N-glycans have been implicated to be involved in growth regulation of cells. In the present study we compared the galactosylation of cell surface N-glycans of mouse Balb/3T3 cells between 30 and 100% densities and found the β-1,4-galactosylation of N-glycans increases predominantly in a 100-kDa protein band on lectin blot analysis in combination with digestions by diplococcal β-galactosidase and N-glycanase. When cells at 100% density were treated with jack bean β-galactosidase, the incorporation of 5-bromodeoxyuridine into the cells was stimulated in a dose-dependent manner, suggesting the involvement of the galactose residues in growth regulation of cells. A galactose-binding protein was isolated from the plasma membranes of cells at 100% density by affinity chromatography using an asialo-transferrin-Sepharose column and found to be galectin-3 as revealed by mass spectrometric analysis. The addition of recombinant galectin-3 into cells at 50% density inhibited the incorporation of 5-bromodeoxyuridine in a dose-dependent manner, but the inhibition was prevented with haptenic sugar. An immunocytochemical study showed that galectin-3 is present at the surface of cells at 100% density but not at 30% density where it locates inside the cells. Several glycoproteins bind to a galectin-3-immobilized column, a major of which was identified as vascular cell adhesion molecule (VCAM)-1. Immunocytochemical studies showed that some galectin-3 and VCAM-1 co-localize at the surface of cells at 100% density, indicating that the binding of galectin-3 secreted from cells to VCAM-1 is one of the pathways involved in the growth regulation of Balb/3T3 cells. 相似文献
1000.
Saori Hata Sayaka Fujishige Yoichi Araki Naoko Kato Masahiko Araseki Masaki Nishimura Dieter Hartmann Paul Saftig Falk Fahrenholz Miyako Taniguchi Katsuya Urakami Hiroyasu Akatsu Ralph N. Martins Kazuo Yamamoto Masahiro Maeda Tohru Yamamoto Tadashi Nakaya Sam Gandy Toshiharu Suzuki 《The Journal of biological chemistry》2009,284(52):36024-36033
Alcadeins (Alcs) constitute a family of neuronal type I membrane proteins, designated Alcα, Alcβ, and Alcγ. The Alcs express in neurons dominantly and largely colocalize with the Alzheimer amyloid precursor protein (APP) in the brain. Alcs and APP show an identical function as a cargo receptor of kinesin-1. Moreover, proteolytic processing of Alc proteins appears highly similar to that of APP. We found that APP α-secretases ADAM 10 and ADAM 17 primarily cleave Alc proteins and trigger the subsequent secondary intramembranous cleavage of Alc C-terminal fragments by a presenilin-dependent γ-secretase complex, thereby generating “APP p3-like” and non-aggregative Alc peptides (p3-Alcs). We determined the complete amino acid sequence of p3-Alcα, p3-Alcβ, and p3-Alcγ, whose major species comprise 35, 37, and 31 amino acids, respectively, in human cerebrospinal fluid. We demonstrate here that variant p3-Alc C termini are modulated by FAD-linked presenilin 1 mutations increasing minor β-amyloid species Aβ42, and these mutations alter the level of minor p3-Alc species. However, the magnitudes of C-terminal alteration of p3-Alcα, p3-Alcβ, and p3-Alcγ were not equivalent, suggesting that one type of γ-secretase dysfunction does not appear in the phenotype equivalently in the cleavage of type I membrane proteins. Because these C-terminal alterations are detectable in human cerebrospinal fluid, the use of a substrate panel, including Alcs and APP, may be effective to detect γ-secretase dysfunction in the prepathogenic state of Alzheimer disease subjects. 相似文献