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991.
992.
Gbabode G Negrier P Mondieig D Moreno E Calvet T Cuevas-Diarte MA 《Chemistry and physics of lipids》2008,154(1):68-77
The pentadecanoic acid-heptadecanoic acid (C(15)H(29)OOH-C(17)H(33)OOH) binary system is dealt with in this article. Combined thermal analysis and X-ray powder diffraction experiments are performed to characterize the polymorphism of the pure compounds and of their mixed samples. In particular, modern methods of crystal structure resolution from powder data (direct space methods) are applied in order to investigate and compare the molecular arrangement within the solid phases of the fatty acids considered. A proposal of the binary phase diagram is given. It exhibits no less than eight distinct solid phases stabilized on relatively narrow domains of composition which shows the reduced miscibility of the constituents. Finally, a structural model of one of the intermediate solid solutions is developed which well accounts for the mixing behaviour of the two fatty acids and permits to propose an explanation about their low solid-state miscibility. 相似文献
993.
Raúl Espinosa Evelyn Caballero Alexis Musacchio Ricardo Silva 《Biotechnology letters》2002,24(5):343-346
P64k is a Neisseria meningitidis high molecular weight protein present in meningococcal vaccine preparations. The lpdA gene, codifying for this protein, was cloned in Escherichia coli and the P64k protein was expressed in Escherichia coli K12 W3110 under the control of the tryptophan promoter. The recombinant bacteria were grown in batch or fed-batch cultures. P64k was expressed as an intracellular soluble form at about 40% of the total cellular protein. A final productivity of 215 mg l–1 h–1 and 11 g cell dry wt l–1 were obtained when the fed-batch culture conditions were optimised, compared to 30% of total protein, and a productivity of 76 mg l–1 h–1 and 5.1 g cell dry wt l–1 in batch cultivation. 相似文献
994.
Marcela Low Daniel Sandoval Evelyn Avilés Fernando Pérez Francisco Nualart Juan Pablo Henríquez 《Histochemistry and cell biology》2009,131(5):565-574
Ascorbic acid, the reduced form of vitamin C, functions as a potent antioxidant as well as in cell differentiation. Ascorbate
is taken up by mammalian cells through the specific sodium/ascorbate co-transporters SVCT1 and SVCT2. Although skeletal muscle
contains about 50% of the whole-body vitamin C, the expression of SVCT transporters has not been clearly addressed in this
tissue. In this work, we analysed the expression pattern of SVCT2 during embryonic myogenesis using the chick as model system.
We cloned the chick orthologue of SVCT2 (cSVCT2) that shares 93% identity with the mouse transporter. cSVCT2 mRNA and protein
are expressed during chick embryonic muscle development. Immunohistochemical analyses showed that SVCT2 is preferentially
expressed by type I slow-twitch muscle fibres throughout chick myogenesis as well as in post-natal skeletal muscles of several
species, including human. Our results suggest that SVCT2-mediated uptake of ascorbate is relevant to the oxidative nature
of type I muscle fibres.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
M. Low and D. Sandoval have contributed equally. 相似文献
995.
996.
Pascal Lapébie Eve Gazave Alexander Ereskovsky Romain Derelle Chantal Bézac Emmanuelle Renard Evelyn Houliston Carole Borchiellini 《PloS one》2009,4(6)
Sponges branch basally in the metazoan phylogenetic tree and are thus well positioned to provide insights into the evolution of mechanisms controlling animal development, likely to remain active in adult sponges. Of the four sponge clades, the Homoscleromorpha are of particular interest as they alone show the “true” epithelial organization seen in other metazoan phyla (the Eumetazoa). We have examined the deployment in sponges of Wnt signalling pathway components, since this pathway is an important regulator of many developmental patterning processes. We identified a reduced repertoire of three divergent Wnt ligand genes in the recently-sequenced Amphimedon queenslandica (demosponge) genome and two Wnts from our EST collection from the homoscleromorph Oscarella lobularis, along with well-conserved genes for intracellular pathway components (β-catenin, GSK3β). Remarkably, the two O. lobularis Wnt genes showed complementary expression patterns in relation to the evenly spaced ostia (canal openings) of the exopinacoderm (ectoderm), highly reminiscent of Wnt expression during skin appendage formation in vertebrates. Furthermore, experimental activation of the Wnt/β-catenin pathway using GSK3β inhibitors provoked formation of ectopic ostia, as has been shown for epithelial appendages in Eumetazoa. We thus suggest that deployment of Wnt signalling is a common and perhaps ancient feature of metazoan epithelial patterning and morphogenesis. 相似文献
997.
Aylin Yilmaz Magnus Gisslén Serena Spudich Evelyn Lee Anura Jayewardene Francesca Aweeka Richard W. Price 《PloS one》2009,4(9)
Introduction
Raltegravir is an HIV-1 integrase inhibitor currently used in treatment-experienced HIV-1-infected patients resistant to other drug classes. In order to assess its central nervous system penetration, we measured raltegravir concentrations in cerebrospinal fluid (CSF) and plasma in subjects receiving antiretroviral treatment regimens containing this drug.Methods
Raltegravir concentrations were determined by liquid chromatography tandem mass spectrometry in 25 paired CSF and plasma samples from 16 HIV-1-infected individuals. The lower limit of quantitation was 2.0 ng/ml for CSF and 10 ng/ml for plasma.Results
Twenty-four of the 25 CSF samples had detectable raltegravir concentrations with a median raltegravir concentration of 18.4 ng/ml (range, <2.0–126.0). The median plasma raltegravir concentration was 448 ng/ml (range, 37–5180). CSF raltegravir concentrations correlated with CSF:plasma albumin ratios and CSF albumin concentrations.Conclusions
Approximately 50% of the CSF specimens exceeded the IC95 levels reported to inhibit HIV-1 strains without resistance to integrase inhibitors. In addition to contributing to control of systemic HIV-1 infection, raltegravir achieves local inhibitory concentrations in CSF in most, but not all, patients. Blood-brain and blood-CSF barriers likely restrict drug entry, while enhanced permeability of these barriers enhances drug entry. 相似文献998.
Andrew R. Zolopa Janet Andersen Lauren Komarow Ian Sanne Alejandro Sanchez Evelyn Hogg Carol Suckow William Powderly for the ACTG A study team 《PloS one》2009,4(5)
Background
Optimal timing of ART initiation for individuals presenting with AIDS-related OIs has not been defined.Methods and Findings
A5164 was a randomized strategy trial of “early ART” - given within 14 days of starting acute OI treatment versus “deferred ART” - given after acute OI treatment is completed. Randomization was stratified by presenting OI and entry CD4 count. The primary week 48 endpoint was 3-level ordered categorical variable: 1. Death/AIDS progression; 2. No progression with incomplete viral suppression (ie HIV viral load (VL) ≥50 copies/ml); 3. No progression with optimal viral suppression (ie HIV VL <50 copies/ml). Secondary endpoints included: AIDS progression/death; plasma HIV RNA and CD4 responses and safety parameters including IRIS.282 subjects were evaluable; 141 per arm. Entry OIs included Pneumocytis jirovecii pneumonia 63%, cryptococcal meningitis 12%, and bacterial infections 12%. The early and deferred arms started ART a median of 12 and 45 days after start of OI treatment, respectively.The difference in the primary endpoint did not reach statistical significance: AIDS progression/death was seen in 20 (14%) vs. 34 (24%); whereas no progression but with incomplete viral suppression was seen in 54 (38%) vs. 44 (31%); and no progression with optimal viral suppression in 67 (48%) vs 63 (45%) in the early vs. deferred arm, respectively (p = 0.22). However, the early ART arm had fewer AIDS progression/deaths (OR = 0.51; 95% CI = 0.27–0.94) and a longer time to AIDS progression/death (stratified HR = 0.53; 95% CI = 0.30–0.92). The early ART had shorter time to achieving a CD4 count above 50 cells/mL (p<0.001) and no increase in adverse events.Conclusions
Early ART resulted in less AIDS progression/death with no increase in adverse events or loss of virologic response compared to deferred ART. These results support the early initiation of ART in patients presenting with acute AIDS-related OIs, absent major contraindications.Trial Registration
ClinicalTrials.gov NCT00055120相似文献999.
1000.
Evelyn Korkor Ansah Solomon Narh-Bana Sabina Asiamah Vivian Dzordzordzi Kingsley Biantey Kakra Dickson John Owusu Gyapong Kwadwo Ansah Koram Brian M Greenwood Anne Mills Christopher J. M Whitty 《PLoS medicine》2009,6(1)