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991.
Amiot L Ferrone S Grosse-Wilde H Seliger B 《Cellular and molecular life sciences : CMLS》2011,68(3):417-431
Although the expression of the non-classical HLA class I molecule HLA-G was first reported to be restricted to the fetal–maternal
interface on the extravillous cytotrophoblasts, the distribution of HLA-G in normal tissues appears broader than originally
described. HLA-G expression was found in embryonic tissues, in adult immune privileged organs, and in cells of the hematopoietic
lineage. More interestingly, under pathophysiological conditions HLA-G antigens may be expressed on various types of malignant
cells suggesting that HLA-G antigen expression is one strategy used by tumor cells to escape immune surveillance. In this
article, we will focus on HLA-G expression in cancers of distinct histology and its association with the clinical course of
diseases, on the underlying molecular mechanisms of impaired HLA-G expression, on the immune tolerant function of HLA-G in
tumors, and on the use of membrane-bound and soluble HLA-G as a diagnostic or prognostic biomarker to identify tumors and
to monitor disease stage, as well as on the use of HLA-G as a novel therapeutic target in cancer. 相似文献
992.
993.
In 1905, Albert Einstein proposed that the forces that cause the random Brownian motion of a particle also underlie the resistance
to macroscopic motion when a force is applied. This insight, of a coupling between fluctuation (stochastic behavior) and responsiveness
(non-stochastic behavior), founded an important branch of physics. Here we argue that his insight may also be relevant for
understanding evolved biological systems, and we present a ‘fluctuation–response relationship’ for biology. The relationship
is consistent with the idea that biological systems are similarly canalized to stochastic, environmental, and genetic perturbations.
It is also supported by in silico evolution experiments, and by the observation that ‘noisy’ gene expression is often both
more responsive and more ‘evolvable’. More generally, we argue that in biology there is (and always has been) an important
role for macroscopic theory that considers the general behavior of systems without concern for their intimate molecular details. 相似文献
994.
Hosseinkhani S 《Cellular and molecular life sciences : CMLS》2011,68(7):1167-1182
Firefly luciferase-catalyzed reaction proceeds via the initial formation of an enzyme-bound luciferyl adenylate intermediate.
The chemical origin of the color modulation in firefly bioluminescence has not been understood until recently. The presence
of the same luciferin molecule, in combination with various mutated forms of luciferase, can emit light at slightly different
wavelengths, ranging from red to yellow to green. A historical perspective of development in understanding of color emission
mechanism is presented. To explain the variation in the color of the bioluminescence, different factors have been discussed
and five hypotheses proposed for firefly bioluminescence color. On the basis of recent results, light-color modulation mechanism
of firefly luciferase propose that the light emitter is the excited singlet state of OL− [1(OL−)*], and light emission from 1(OL−)* is modulated by the polarity of the active-site environment at the phenol/phenolate terminal of the benzothiazole fragment
in oxyluciferin. 相似文献
995.
Terhi Vihervaara Riikka-Liisa Uronen Gerd Wohlfahrt Ingemar Björkhem Elina Ikonen Vesa M. Olkkonen 《Cellular and molecular life sciences : CMLS》2011,68(3):537-551
ORP1L is an oxysterol binding homologue that regulates late endosome (LE) positioning. We show that ORP1L binds several oxysterols
and cholesterol, and characterize a mutant, ORP1L Δ560–563, defective in oxysterol binding. While wild-type ORP1L clusters
LE, ORP1L Δ560–563 induces LE scattering, which is reversed by disruption of the endoplasmic reticulum (ER) targeting FFAT
motif, suggesting that it is due to enhanced LE–ER interactions. Endosome motility is reduced upon overexpression of ORP1L.
Both wild-type ORP1L and the Δ560–563 mutant induce the recruitment of both dynactin and kinesin-2 on LE. Most of the LE decorated
by overexpressed ORP1L fail to accept endocytosed dextran or EGF, and the transfected cells display defective degradation
of internalized EGF. ORP1L silencing in macrophage foam cells enhances endosome motility and results in inhibition of [3H]cholesterol efflux to apolipoprotein A-I. These data demonstrate that LE motility and functions in both protein and lipid
transport are regulated by ORP1L. 相似文献
996.
997.
Ververis K Rodd AL Tang MM El-Osta A Karagiannis TC 《Cellular and molecular life sciences : CMLS》2011,68(24):4101-4114
Histone deacetylase inhibitors have emerged as a new class of anticancer therapeutics with suberoylanilide hydroxamic acid
(Vorinostat) and depsipeptide (Romidepsin) already being approved for clinical use. Numerous studies have identified that
histone deacetylase inhibitors will be most effective in the clinic when used in combination with conventional cancer therapies
such as ionizing radiation and chemotherapeutic agents. One promising combination, particularly for hematologic malignancies,
involves the use of histone deacetylase inhibitors with the anthracycline, doxorubicin. However, we previously identified
that trichostatin A can potentiate doxorubicin-induced hypertrophy, the dose-limiting side-effect of the anthracycline, in
cardiac myocytes. Here we have the extended the earlier studies and evaluated the effects of combinations of the histone deacetylase
inhibitors, trichostatin A, valproic acid and sodium butyrate on doxorubicin-induced DNA double-strand breaks in cardiomyocytes.
Using γH2AX as a molecular marker for the DNA lesions, we identified that all of the broad-spectrum histone deacetylase inhibitors
tested augment doxorubicin-induced DNA damage. Furthermore, it is evident from the fluorescence photomicrographs of stained
nuclei that the histone deacetylase inhibitors also augment doxorubicin-induced hypertrophy. These observations highlight
the importance of investigating potential side-effects, in relevant model systems, which may be associated with emerging combination
therapies for cancer. 相似文献
998.
999.
Khan ZU Martín-Montañez E Baxter MG 《Cellular and molecular life sciences : CMLS》2011,68(10):1737-1754
Visual perception and memory are the most important components of vision processing in the brain. It was thought that the
perceptual aspect of a visual stimulus occurs in visual cortical areas and that this serves as the substrate for the formation
of visual memory in a distinct part of the brain called the medial temporal lobe. However, current evidence indicates that
there is no functional separation of areas. Entire visual cortical pathways and connecting medial temporal lobe are important
for both perception and visual memory. Though some aspects of this view are debated, evidence from both sides will be explored
here. In this review, we will discuss the anatomical and functional architecture of the entire system and the implications
of these structures in visual perception and memory. 相似文献
1000.
Naturally occurring antimicrobial peptides (AMPs) present several drawbacks that strongly limit their development into therapeutically
valuable antibiotics. These include susceptibility to protease degradation and high costs of manufacture. To overcome these
problems, researchers have tried to develop mimics or peptidomimetics endowed with better properties, while retaining the
basic features of membrane-active natural AMPs such as cationic charge and amphipathic design. Protein epitope mimetics, multimeric
(dendrimeric) peptides, oligoacyllysines, ceragenins, synthetic lipidated peptides, peptoids and other foldamers are some
of the routes explored so far. The synthetic approach has led to compounds that have already entered clinical evaluation for
the treatment of specific conditions, such as Staphylococcus (MRSA) infections. Should these trials be successful, an important proof-of-concept would be established, showing that synthetic
oligomers rather than naturally occurring molecules could bring peptide-based antibiotics to clinical practice and the drug
market for local and systemic treatment of medical conditions associated with multi-drug resistant pathogens. 相似文献