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911.
Sreenivasan VK Stremovskiy OA Kelf TA Heblinski M Goodchild AK Connor M Deyev SM Zvyagin AV 《Bioconjugate chemistry》2011,22(9):1768-1775
Somatostatin (SST) is a peptide neurotransmitter/hormone found in several mammalian tissue types. Apart from its natural importance, labeled SST/analogues are utilized in clinical applications such as targeting/diagnosis of neuroendocrine tumors. We report on the development and characterization of a novel, recombinant, fluorescent somatostatin analogue that has potential to elucidate somatostatin-activated cell signaling. SST was genetically fused with a monomeric-red fluorescent protein (mRFP) as the fluorescent label. The attachment of SST to mRFP had no detectable effect on its fluorescent properties. This analogue's potency to activate the endogenous and transfected somatostatin receptors was characterized using assays of membrane potential and Ca(2+) mobilization and immunocytochemistry. SST-mRFP was found to be an effective somatostatin receptor agonist, able to trigger the membrane hyperpolarization, mobilization of the intracellular Ca(2+) and receptor-ligand internalization in cells expressing somatostatin receptors. This complex represents a novel optical reporter due to its red emission spectral band suitable for in vivo imaging and tracking of the somatostatin receptor signaling pathways, affording higher resolution and sensitivity than those of the state-of-the-art radiolabeling bioassays. 相似文献
912.
Live-cell visualization of dynamics of HIV budding site interactions with an ESCRT component 总被引:1,自引:0,他引:1
Baumgärtel V Ivanchenko S Dupont A Sergeev M Wiseman PW Kräusslich HG Bräuchle C Müller B Lamb DC 《Nature cell biology》2011,13(4):469-474
HIV (human immunodeficiency virus) diverts the cellular ESCRT (endosomal sorting complex required for transport) machinery to promote virion release from infected cells. The ESCRT consists of four heteromeric complexes (ESCRT-0 to ESCRT-III), which mediate different membrane abscission processes, most importantly formation of intralumenal vesicles at multivesicular bodies. The ATPase VPS4 (vacuolar protein sorting 4) acts at a late stage of ESCRT function, providing energy for ESCRT dissociation. Recruitment of ESCRT by late-domain motifs in the viral Gag polyprotein and a role of ESCRT in HIV release are firmly established, but the order of events, their kinetics and the mechanism of action of individual ESCRT components in HIV budding are unclear at present. Using live-cell imaging, we show late-domain-dependent recruitment of VPS4A to nascent HIV particles at the host cell plasma membrane. Recruitment of VPS4A was transient, resulting in a single or a few bursts of at least two to five VPS4 dodecamers assembling at HIV budding sites. Bursts lasted for ~35 s and appeared with variable delay before particle release. These results indicate that VPS4A has a direct role in membrane scission leading to HIV-1 release. 相似文献
913.
Nucleation of nuclear bodies by RNA 总被引:1,自引:0,他引:1
914.
Piletska EV Stavroulakis G Larcombe LD Whitcombe MJ Sharma A Primrose S Robinson GK Piletsky SA 《Biomacromolecules》2011,12(4):1067-1071
Here we present the first molecular imprinted polymer (MIP) that is able to attenuate the biofilm formation of the opportunistic human pathogen Pseudomonas aeruginosa through specific sequestration of its signal molecule N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C(12)-AHL). The MIP was rationally designed using computational modeling, and its capacity and specificity and that of a corresponding blank polymer toward signal molecule of P. aeruginosa (3-oxo-C(12)-AHL) and its analogue were tested. The biofilm formation in the presence of polymers and without polymers was studied using scanning confocal laser microscopy. Staining with crystal violet dye was used for the quantification of the biofilm formation. A significant reduction of the biofilm growth was observed in the presence of MIP (>80%), which was superior to that of the resin prepared without template, which showed a reduction of 40% in comparison with biofilm, which was grown without polymer addition. It was shown that 3-oxo-C(12)-AHL-specific MIP prevented the development of quorum-sensing-controlled phenotypes (in this case, biofilm formation) from being up-regulated. The developed MIP could be considered as a new tool for the elimination of life-threatening infections in a multitude of practical applications; it could, for example, be grafted on the surface of medical devices such as catheters and lenses, be a component of paints, or be used as a wound adsorbent. 相似文献
915.
916.
917.
Elena Klyachkovskaya Natalia Strekal Inna Motevich Svetlana Vaschenko Anna Harbachova Mikhail Belkov Sergey Gaponenko Christian Dais Hans Sigg Toma Stoica Detlev Grützmacher 《Plasmonics (Norwell, Mass.)》2011,6(2):413-418
Semiconductor self-assembled Ge-on-Si quantum dot structures coated with Au film were successfully employed as surface-enhanced Raman scattering (SERS) substrates to characterize ultramarine blue inorganic art pigment. To assign the bands and to reveal the enhancement mechanisms, the quantum-chemical calculations of vibration spectra of linear and cyclic model compound of SiO4 and AlO4 tetrahedra were carried out. The overtones are observed in the SERS spectra and the unharmonicity constants were estimated. The development of a series of new bands in SERS spectra of ultramarine are discussed in terms of electro-optical unharmonicity. 相似文献
918.
Feldkamp ML Carey JC Pimentel R Krikov S Botto LD 《Birth defects research. Part A, Clinical and molecular teratology》2011,91(10):873-878
BACKGROUND: Gastroschisis remains an epidemiologic and pathogenetic dilemma, with genetics not thought to play a significant role in its etiology. The purpose of this study was to determine which gastroschisis cases in the Utah Birth Defect Network (UBDN) were related and the excess familial risk among multigenerational families. METHODS: Gastroschisis cases born from 1997 through 2008 were identified from the statewide population‐based UBDN and linked with the Utah Population Database (UPDB) to access multigenerational pedigrees. We analyzed these pedigrees using the familial standardized incidence ratio (FSIR). RESULTS: Of the 284 UBDN gastroschisis cases, one in 40 (n = 7; 2.5%) were reported to have another affected family member. Among these seven cases, three had affected sib pairs and four reported either a distant cousin, paternal uncle, maternal half‐uncle, or paternal cousin with gastroschisis. UBDN‐UPDB–linked cases resulted in many multigenerational pedigrees with the same affected descendents through marriage. We selected 30 pedigrees for repeated analysis based on two parameters: highest FSIRs with a p ≤ 0.01 and ≥2 cases. In these 30 pedigrees, FSIRs ranged from 3.7 to 93.5 (p < 0.009), each with two to eight distantly related cases (n = 64 distinct cases, representing 23% of the 284). CONCLUSIONS: We found a statistically significant excess risk for gastroschisis because of familial factors. Similar to many other birth defects, gastroschisis may fit a multifactorial model of inheritance. The UBDN‐UPDB linkage provides a robust approach to investigating genetic factors. Genetic susceptibility should be further investigated because it may have a greater role in the etiology of gastroschisis than currently appreciated. Birth Defects Research (Part A), 2011. © 2011 Wiley‐Liss, Inc. 相似文献
919.
Grigoryev A Savchuk S Melnik A Moskaleva N Dzhurko J Ershov M Nosyrev A Vedenin A Izotov B Zabirova I Rozhanets V 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(15-16):1126-1136
The Russian Federation prohibited the distribution of herbal mixtures with synthetic aminoalkylindoles JWH-018 and JWH-073, agonist cannabinoid receptors, on January 22, 2010. The lack or low content of their native compounds in urine requires detailed identification of their metabolites, which are excreted with urine and are present in blood. Using gas and liquid chromatography-mass spectrometry, we identified a series of metabolites in urine samples from humans and rats that were products of the following reactions: (a) mono- and dihydroxylation of the parent compounds with hydroxyl groups located at aromatic and aliphatic residues, (b) carboxylation, (c) N-dealkylation and (d) N-dealkylation and hydroxylation. The prevailing urinary metabolites in humans are monohydroxylated forms, while N-dealkylated and N-dealkyl monohydroxylated forms are found in rats. Twenty-six samples of herbal smoking mixtures with JWH-018, purchased in Russia, were analysed. 相似文献
920.
Danilov SM Gordon K Nesterovitch AB Lünsdorf H Chen Z Castellon M Popova IA Kalinin S Mendonca E Petukhov PA Schwartz DE Minshall RD Sturrock ED 《PloS one》2011,6(10):e25952