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11.
Behm Katri Nappa Marja Aro Nina Welman Alan Ledgard Stewart Suomalainen Marjut Hill Jeremy 《The International Journal of Life Cycle Assessment》2022,27(8):1017-1034
The International Journal of Life Cycle Assessment - This paper studies the carbon footprint and water scarcity footprint (WSF) of a milk protein, beta-lactoglobulin, produced by cellular... 相似文献
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Regan EA Mazur W Meoni E Toljamo T Millar J Vuopala K Bowler RP Rahman I Nicks ME Crapo JD Kinnula VL 《Free radical biology & medicine》2011,51(3):726-732
Extracellular superoxide dismutase (ECSOD) is the major superoxide-scavenging enzyme in the lung. Certain ECSOD polymorphisms are protective against COPD. We postulated that smokers and COPD subjects would have altered levels of ECSOD in the lung, airway secretions, and/or plasma. Lung tissue ECSOD was evaluated from nonsmokers, smokers, and subjects with mild to very severe COPD by Western blot, immunohistochemistry, and ELISA. ECSOD levels in plasma, bronchoalveolar lavage fluid (BALF), and induced-sputum supernatants were analyzed by ELISA and correlated with smoking history and disease status. Immunohistochemistry identified ECSOD in extracellular matrix around bronchioles, arteries, and alveolar walls, with decreases seen in the interstitium and vessels of severe COPD subjects using digital image analysis. Plasma ECSOD did not differ between COPD subjects and controls nor based on smoking status. ECSOD levels in induced sputum supernatants were elevated in current smokers and especially in COPD subjects compared to nonsmokers, whereas corresponding changes could not be seen in the BALF. ECSOD expression was reduced around vessels and bronchioles in COPD lungs. Substantial increases in sputum ECSOD in smokers and COPD is interpreted as an adaptive response to increased oxidative stress and may be a useful biomarker of disease activity in COPD. 相似文献
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Jokela M Raki M Heikkinen K Sepponen K Eskelinen A Syväoja JE 《Protein expression and purification》2005,43(1):73-84
The B-subunits of replicative DNA polymerases belong to the superfamily of calcineurin-like phosphoesterases and are conserved from Archaea to humans. Recently we and others have shown that the B-subunit (DP1) of the archaeal family D DNA polymerase is responsible for proofreading 3'-5' exonuclease activity. The similarity of B-subunit sequences implies a common fold, but since the key catalytic and metal binding residues of the phosphoesterase domain are disrupted in the eukaryotic B-subunits, their common function has not been identified. To study the structure and activities of B-subunits in more detail, we expressed 13 different recombinant B-subunits in Escherichia coli. We found that the solubility of a protein could be predicted from the calculated GRAVY score. These scores were useful for the selection of proteins for successful expression. We optimized the expression and purification of Methanocaldococcus (Methanococcus) jannaschii DP1 of DNA polymerase D (MjaDP1) and show that the protein co-purifies with a thermostable nuclease activity. Truncation of the protein indicates that the N-terminus (aa 1-134) is not needed for catalysis. The C-terminal part of the protein containing both the calcineurin-like phosphoesterase domain and the OB-fold is sufficient for the nuclease activity. 相似文献
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Avoidance of incestuous matings is widely reported across many animal taxa, and the adaptive value of such behavior is explained through inbreeding depression. However, an old and somewhat neglected theoretical result predicts that inbred matings offer another, positive effect on the inclusive fitness of parents: an individual who mates with a relative will help that relative to spread genes identical by descent. This benefit can be substantial, if the additional mating achieved by the relative does not harm his mating success otherwise, and in the context of selfing in plants the phenomenon is well known. Here, we develop a model that derives expected values of inbreeding tolerance, that is, the magnitude of inbreeding depression that is required to make individuals avoid inbreeding, for different animal life histories and parental investment patterns. We also distinguish between simultaneous and sequential mate choice, and show that inbreeding tolerance should often be remarkably high in the latter scenario in particular, although egalitarian parental care will lead to lower tolerance. There is a mismatch between theory and data: the almost complete lack of cases where individuals prefer to mate incestuously is at odds with a large overlap between the predicted range of inbreeding tolerance and estimates of inbreeding depression found in nature. We discuss four different solutions to this enigma, and suggest that inbreeding tolerance, where it is found, should not always be attributed to a simple constraint that has prevented finding any other mate. 相似文献
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Sundvall M Korhonen A Vaparanta K Anckar J Halkilahti K Salah Z Aqeilan RI Palvimo JJ Sistonen L Elenius K 《The Journal of biological chemistry》2012,287(27):23216-23226
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Jürgen Brem Mihaela C. TurcuCsaba Paizs Katri LundellMonica-Ioana To?a Florin-Dan IrimieLiisa T. Kanerva 《Process Biochemistry》2012,47(1):119-126
Lipase AK “Amano” 20 from Pseudomonas fluorescens (PFL) was immobilized using diverse immobilization techniques. The methods developed, especially the optimized sol-gel procedure, enabled the fine tuning of enzymatic activity and enantioselectivity for the kinetic resolution of racemic ethyl 3-aryl-3-hydroxypropanoates. The aryl moieties of the racemates include furan-2 and 3-yl, thiophen-2 and 3-yl, benzofuran-2-yl, benzo[b]thiophen-2-yl, as well as phenyl and 4-chloro- and 4-methoxyphenyl groups. The optimized PFL sol-gel preparation (encapsulation from the aqueous solution of PFL, sucrose and Celite in situ) was shown to be efficiently reusable in ten cycles and highly enantioselective with E > 200 to all other substrates except furan-2 and 3-yl and thiophen-2 and 3-yl substituted compounds with E 108-184. 相似文献
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