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51.
核苷酸、聚核苷酸和核酸猝灭Tb3+-钛铁试剂络合物荧光的机理研究 总被引:1,自引:0,他引:1
研究了核苷酸、聚核苷酸和核酸对Tb3+-钛铁试剂(TR)络合物的荧光碎灭机理,认为荧光猝灭过程是核苷酸、聚核苷酸和核酸分子中的磷酸基组分与TR竞争Tb3+离子,生成实验条件下无荧光的二元络合物的静态猝灭过程;用Tb3+-TR络合物荧光探针研究DNA嵌入剂和金属离子与DNA相互作用的实验结果说明这一机理是合理的. 相似文献
52.
本文主要概述了近年来核酸工具酶辅助的基于金属稳定同位素标记的电感耦合等离子体质谱(ICP-MS)检测方法在生物分析中的发展和应用,简要介绍了该方法在蛋白质、核酸及一些生物小分子检测中的应用。最后对核酸工具酶辅助的基于金属稳定同位素标记的电感耦合等离子体质谱(ICP-MS)检测方法的发展前景做了展望。 相似文献
53.
Ulf Diederichsen Harald W. Schmitt 《Angewandte Chemie (International ed. in English)》1998,37(3):302-305
Self-pairing complexes with extraordinarily high stability are formed by β-PNAs with four to six units of the nucleo-β-amino acid 1 . The key step in the synthesis is a Mitsunobu reaction between a β-homoserine and a purine derivative. 相似文献
54.
Christof M. Niemeyer Dietmar Blohm 《Angewandte Chemie (International ed. in English)》1999,38(19):2865-2869
The complete human genes (ca. 100 000) as well as the whole spectrum of biological diversity should soon be able to be analyzed simultaneously by means of DNA microarrays using the fast technical advances that are occurring in this area. The particular strength of array analysis, typically based on the hybridization of nucleic acid probes attached to microchips with labeled RNA or DNA samples, results from the highly redundant measurement of many parallel hybridization events (see picture), which leads to an extraordinary level of assay validation. 相似文献
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Pedro Carmona Arantxa Rodríguez-Casado Marina Molina 《Analytical and bioanalytical chemistry》2009,393(4):1289-1295
We describe the improvement of a novel approach to investigating hydrogen/deuterium (H/D) exchange kinetics in biomolecules
using transmission infrared spectroscopy. The method makes use of a Fourier transform infrared spectrometer coupled with a
microdialysis flow cell to determine exchange rates of labile hydrogens. With this cell system, the monitoring of exchange
reactions has been studied here as a function of some cell characteristics such as: (a) dialysis membrane surface contacting
both the H2O and D2O compartments; (b) molecular cutoff of dialysis membrane; and (c) distance between the cell-filling holes. The best improvement
has been obtained by increasing the dialysis membrane surface followed by increase of molecular cutoff. However, not significant
differences were found using various distances between filling holes. The fastest exchange rate which can be measured with
the cell system used here is found to be k = 0.41 ± 0.02 min−1, that is, about threefold greater than the one got in a previous work. This microdialysis flow cell has been used here for
the study of H/D exchange in nucleic acids with subsequent structural analysis by 2D correlation spectroscopy. 相似文献
59.
Molecular diagnostics of infectious diseases, in particular, nucleic-acid-based methods, are the fastest growing field in
clinical laboratory diagnostics. These applications are stepwise replacing or complementing culture-based, biochemical, and
immunological assays in microbiology laboratories. The first-generation nucleic acid assays were monoparametric such as conventional
tests, determining only a single parameter. Improvements and new approaches in technology now open the possibility for the
development of multiparameter assays using microarrays, multiplex nucleic acid amplification techniques, or mass spectrometry,
while the introduction of closed-tube systems has resulted in rapid microbial diagnostics with a subsequently reduced contamination
risk. Whereas the first assays were focused on the detection and identification of microbial pathogens, these new technologies
paved the way for the parallel determination of multiple antibiotic resistance determinants or to perform microbial epidemiology
and surveillance on a genetic level. 相似文献
60.
采用MP2/6-31+G(d,p)方法优化得到了22个由精氨酸侧链与碱基尿嘧啶、 胸腺嘧啶、 胞嘧啶、 鸟嘌呤及腺嘌呤形成的氢键复合物的气相稳定结构, 使用包含BSSE校正的MP2/aug-cc-pVTZ方法计算得到了复合物的气相结合能, 通过MP2/6-31+G(d,p)方法和PCM模型优化得到了复合物的水相稳定结构, 采用MP2/aug-cc-pVTZ方法和PCM模型计算得到了复合物的水相结合能. 研究发现, 精氨酸侧链与碱基间的离子氢键作用强度与单体间电荷转移量、 氢键临界点电子密度及二阶作用稳定化能密切相关. 与中性氢键相比, 离子氢键作用具有更显著的共价作用成分. 研究还发现, 精氨酸侧链和碱基间形成的氢键复合物的稳定性次序可以通过氢键受体碱基分子上氧原子和氮原子的质子化反应焓变进行预测, 质子化反应焓变越负, 形成的氢键复合物越稳定. 相似文献