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71.
Piechota M Banach M Irzmański R Misztal M Rysz J Barylski M Piechota-Urbańska M Kowalski J Pawlicki L 《Cellular & molecular biology letters》2007,12(2):162-175
The aim of this study was to find the relationship between N-terminal brain natriuretic propeptide (NT-proBNP), procalcitonin
(PCT) and C-reactive protein (CRP) plasma concentrations in septic patients. This was a prospective study, performed at Medical
University Hospital No. 5 in łódź. Twenty patients with sepsis and severe sepsis were included in the study. N-terminal brain
natriuretic propeptide, procalcitonin and C-reactive protein concentrations, and survival were evaluated. In the whole studied
group (128 measurements), the mean NT-proBNP, procalcitonin and C-reactive protein concentrations were, respectively: 140.80±84.65
pg/ml, 22.32±97.41 ng/ml, 128.51±79.05 mg/l. The correlations for the NT-proBNP level and procalcitonin and C-reactive protein
levels were 0.3273 (p<0.001) and 0.4134 (p<0.001), respectively. NT-proBNP levels correlate with PCT and CRP levels in septic
patients. In the survivor subgroup, the mean NT-proBNP plasma concentrations were significantly lower than in the non-survivor
subgroup. 相似文献
72.
Kulczykowska E Kasprzak M Kalamarz H Kuriata M Nietrzeba M Jerzak L Kamiński P 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,146(3):392-397
There is growing evidence that ubiquitous environmental contaminants may interfere with vertebrate endocrine systems. The selected endocrine biomarkers are used to indicate the condition of free-ranging populations of wildlife, including avian species. The aim of this study was to determine the impact of environment quality on serum thyroxine (T4) and melatonin (Mel) in white stork nestlings (Ciconia ciconia) living in different locations: small villages in natural areas surrounded by forests and crop fields, near the city and near the copper smelter. We extended our analyses to examine the hormones' day-night changes in conjunction with chicks' age. Total serum T4 and Mel was measured by RIA. T4 level, as a decisive measure of thyroid hormone productivity, was significantly lower in the nestlings exposed to pollutants from the copper smelter. Mel, as a well-known scavenger of free radicals, was elevated in the nestlings in the area near the copper smelter. This study indicates that alteration in T4 and Mel levels could be a useful marker of exposure of nestling wild storks to different toxic substances in field studies. Mel is postulated to be a susceptible defensive molecule as a protective mechanism for organisms. 相似文献
73.
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75.
Mariusz A. Bromke Anton Hochmuth Takayuki Tohge Alisdair R. Fernie Patrick Giavalisco Asdrubal Burgos Lothar Willmitzer Yariv Brotman 《The Plant journal : for cell and molecular biology》2015,81(3):529-536
Quantification of fatty acids has been crucial to elucidate lipid biosynthesis pathways in plants. To date, fatty acid identification and quantification has relied mainly on gas chromatography (GC) coupled to flame ionization detection (FID) or mass spectrometry (MS), which requires the derivatization of samples and the use of chemical standards for annotation. Here we present an alternative method based on a simple procedure for the hydrolysis of lipids, so that fatty acids can be quantified by liquid chromatography mass spectrometry (LC‐MS) analysis. Proper peak annotation of the fatty acids in the LC‐MS‐based methods has been achieved by LC‐MS measurements of authentic standard compounds and elemental formula annotation supported by 13C isotope‐labeled Arabidopsis. As a proof of concept, we have compared the analysis by LC‐MS and GC‐FID of two previously characterized Arabidopsis thaliana knock‐out mutants for FAD6 and FAD7 desaturase genes. These results are discussed in light of lipidomic profiles obtained from the same samples. In addition, we performed untargeted LC‐MS analysis to determine the fatty acid content of two diatom species. Our results indicate that both LC‐MS and GC‐FID analyses are comparable, but that because of higher sensitivity and selectivity the LC‐MS‐based method allows for a broader coverage and determination of novel fatty acids. 相似文献
76.
Katarzyna Kapczyńska Piotr Stefanowicz Łukasz Jaremko Mariusz Jaremko Alicja Kluczyk Zbigniew Szewczuk 《Amino acids》2011,40(3):923-932
Protein glycation is often a cause of diabetes-associated complications. The isotopically labeled peptide-derived Amadori
products may serve as standards for quantitative determination of the glycated proteins. In this paper, we discussed various
approaches to the synthesis of Amadori products labeled selectively with stable isotopes 2H, 13C and 18O. 相似文献
77.
Chow R Lin A Tonai R Bolanos R Connor C Mendoza A Heminger R Chow M Ho E Kang J Gindy L Fu C Rao A Gau JF Wang BC Klich I Ratajczak J Ratajczak M Petz LD 《Cytotherapy》2011,13(9):1105-1119
Background aimsLimited cell dose has hampered the use of cord blood transplantation (CBT) in adults. One method of minimizing nucleated cell loss in cord blood (CB) processing is to deplete or reduce plasma but not red blood cells - plasma depletion/reduction (PDR).MethodsThe nucleated cell loss of PDR was studied, and determined to be less than 0.1% in the discarded supernatant plasma fraction in validation experiments. After testing and archival sampling, the median nucleated cell recovery for PDR processing was 90%, and median CD34+ cell recovery 88%. In a CB bank inventory of 12 339 products with both pre- and post-processing total nucleated cells (TNC), PDR processing resulted in median post-processing TNC recoveries of 90.0% after testing and archival samples removal. Using the same 10 CB units divided into two halves, we compared directly the recovery of PDR against hydroxyethyl starch red cell reduction (RCR) for TNC, CD34+ cells and colony-forming units (CFU-GM, CFU-E, CFU-GEMM and total CFU) after parallel processing. We also compared the loss of very small embryonic-like stem cells (VSEL).ResultsWe demonstrated significantly higher recoveries using PDR for TNC (124%), CD34+ cells (121%), CFU-GM (225%), CFU-GEMM (201%), total CFU (186%) and VSEL (187%). The proportion of high TNC products was compared between 10 912 PDR and 38 819 RCR CB products and found to be 200% higher for products that had TNC ≥150 × 107 (P = 0.0001) for the PDR inventory.ConclusionsOur data indicate that PDR processing of CB provides a significantly more efficient usage of this valuable and scarce resource. 相似文献
78.
Mitoraj MP Parafiniuk M Srebro M Handzlik M Buczek A Michalak A 《Journal of molecular modeling》2011,17(9):2337-2352
The present study characterizes changes in the electronic structure of reactants during chemical reactions based on the combined
charge and energy decomposition scheme, ETS-NOCV (extended transition state–natural orbitals for chemical valence). Decomposition
of the activation barrier, ΔE
#, into stabilizing (orbital interaction, ΔE
orb, and electrostatic, ΔE
elstat) and destabilizing (Pauli repulsion, ΔE
Pauli, and geometry distortion energy, ΔE
dist) factors is discussed in detail for the following reactions: (I) hydrogen cyanide to hydrogen isocyanide, HCN → CNH isomerization; (II) Diels-Alder cycloaddition of ethene to 1,3-butadiene; and two catalytic processes, i.e., (III) insertion of ethylene into the metal-alkyl bond using half-titanocene with phenyl-phenoxy ligand catalyst; and (IV) B–H bond activation catalyzed by an Ir-containing catalyst. Various reference states for fragments were applied in ETS-NOCV
analysis. We found that NOCV-based deformation densities (Δρ
i) and the corresponding energies ΔE
orb(i) obtained from the ETS-NOCV scheme provide a very useful picture, both qualitatively and quantitatively, of electronic
density reorganization along the considered reaction pathways. Decomposition of the barrier ΔE# into stabilizing and destabilizing contributions allowed us to conclude that the main factor responsible for the existence
of positive values of ΔE
# for all processes (I, II, III and IV) is Pauli interaction, which is the origin of steric repulsion. In addition, in the case of reactions II, III and IV, a significant degree of structural deformation of the reactants, as measured by the geometry distortion energy, plays an
important role. Depending on the reaction type, stabilization of the transition state (relatively to the reactants) originating
either from the orbital interaction term or from electrostatic attraction can be of vital importance. Finally, use of the
ETS-NOCV method to describe catalytic reactions allows extraction of information on the role of catalysts in determination
of ΔE
#. 相似文献
79.
Recent studies have revealed a role for the ubiquitin/proteasome system in the regulation and turnover of outer mitochondrial membrane (OMM)-associated proteins. Although several molecular components required for this process have been identified, the mechanism of proteasome-dependent degradation of OMM-associated proteins is currently unclear. We show that an AAA-ATPase, p97, is required for the proteasomal degradation of Mcl1 and Mfn1, two unrelated OMM proteins with short half-lives. A number of biochemical assays, as well as imaging of changes in localization of photoactivable GFP-fused Mcl1, revealed that p97 regulates the retrotranslocation of Mcl1 from mitochondria to the cytosol, prior to, or concurrent with, proteasomal degradation. Mcl1 retrotranslocation from the OMM depends on the activity of the ATPase domain of p97. Furthermore, p97-mediated retrotranslocation of Mcl1 can be recapitulated in vitro, confirming a direct mitochondrial role for p97. Our results establish p97 as a novel and essential component of the OMM-associated protein degradation pathway. 相似文献
80.
Parczewski M Bander D Leszczyszyn-Pynka M Urbanska A Kaczmarczyk M Ciechanowicz A Boron-Kaczmarska A 《PloS one》2011,6(7):e22215