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Towards the aim of creating a functional mimic of isopenicillin N synthase, a small molecule designed to coordinate around iron(II) and model the enzyme active site has been prepared in nine synthetic steps from 2,6-bis(hydroxymethyl)pyridine, (S)-(+)-mandelic acid and pivaldehyde. One aspartate, two histidines and a water ligand in the natural enzyme are replaced by an α-hydroxy acid, pyridine and aniline in the model compound. Additionally, a free thiol designed to simulate the enzyme substrate, δ-(l-α-aminoadipoyl)-l-cysteinyl-d-valine, is linked to the ligand by a three carbon chain. We postulate that in the presence of molecular oxygen, the complex formed between this synthetic ligand and iron(II) will display oxidative chemistry similar to that observed in the active site of isopenicillin N synthase. 相似文献
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Nikolaus Krall Dr. Jörg Scheuermann Prof. Dario Neri 《Angewandte Chemie (International ed. in English)》2013,52(5):1384-1402
The targeted delivery of potent cytotoxic agents has emerged as a promising strategy for the treatment of cancer and other serious conditions. Traditionally, antibodies against markers of disease have been used as drug‐delivery vehicles. More recently, lower molecular weight ligands have been proposed for the generation of a novel class of targeted cytotoxics with improved properties. Advances in this field crucially rely on efficient methods for the identification and optimization of organic molecules capable of high‐affinity binding and selective recognition of target proteins. The advent of DNA‐encoded chemical libraries allows the construction and screening of compound collections of unprecedented size. In this Review, we survey developments in the field of small ligand‐based targeted cytotoxics and show how innovative library technologies will help develop the drugs of the future. 相似文献
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Huege J Krall L Steinhauser MC Giavalisco P Rippka R Tandeau de Marsac N Steinhauser D 《Analytical and bioanalytical chemistry》2011,399(10):3503-3517
Here we describe an integrative protocol for metabolite extraction and the measurement of three cellular constituents, chlorophyll
a, total protein, and glycogen from the same small volume of cyanobacterial cultures that can be used as alternative sample
amount parameters for data adjustment in comparative metabolome studies. We conducted recovery experiments to assess the robustness
and reproducibility of the measurements obtained for the cellular constituents. Also, we have chosen three profile-intrinsic
parameters derived from gas chromatography-mass spectrometry (GC/MS) data in order to test their utility for spectral data
adjustment. To demonstrate the relevance of these six parameters, we analyzed three cyanobacteria with greatly different morphologies,
comprising a unicellular, a filamentous, and a filamentous biofilm-forming strain. Comparative analysis of GC/MS data from
cultures grown under standardized conditions indicated that adjustment of the corresponding metabolite profiles by any of
the measured cellular constituents or chosen intrinsic parameters led to similar results with respect to sample cohesion and
strain separation. Twenty-one metabolites significantly enriched for the carbohydrate and amine superclasses are mainly responsible
for strain separation, with a majority of the remaining metabolites contributing to sample group cohesion. Therefore, we conclude
that any of the parameters tested in this study can be used for spectral data adjustment of cyanobacterial strains grown under
controlled conditions. However, their use for the differentiation between different stresses or physiological states within
a strain remains to be shown. Interestingly, both the adjustment approaches and statistical tests applied effected the detection
of metabolic differences and their patterns among the analyzed strains. 相似文献
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