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51.
Masanori KawasakiKosuke Namba Hidekazu TsujishimaTetsuro Shinada Yasufumi Ohfune 《Tetrahedron letters》2003,44(6):1235-1238
Highly enantioselective synthesis of (2R)-α-(hydroxymethyl)glutamate (1), a selective agonist of mGluR2 and 3, was achieved in short steps using an asymmetric version of the Strecker synthesis. This was converted into its α-methoxymethyl- and α-benzyloxymethyl derivatives 2 and 3, possible ligands as tools to investigate glutamate receptors, via protection of the sterically hindered amino group by means of phase transfer catalyst. 相似文献
52.
Ishmuratov G. Yu. Yakovleva M. P. Galyautdinova A. V. Muslukhov R. R. Tolstikov G. A. 《Russian Chemical Bulletin》2003,52(3):740-744
A new procedure was developed for the synthesis of racemic analogs of 1,5-dimethyl-branched insect pheromones based on monoalkylation of ethyl acetoacetate with 1-acetoxy-5-bromo-3-methylpentane produced upon decyclization of 4-methyltetrahydropyran. 相似文献
53.
Jia Rong Li Li Jun Zhang Xi Quan Yang Qing Li Dong Wang Chun Xia Wang Da Xin Shi Qi Zhang 《中国化学快报》2008,19(1)
Two different skeletons of heterocyclic compounds, quinoline and quinazolinone analogs could be obtained by a novel one-potsynthesis from substituted 3-amino-lH-benzo[f]chromene-2-carbonitrile derivatives and cyclohexanone in DMF in the catalyst ofanhydrous zinc chloride under reflux. A plausible mechanism was proposed. 相似文献
54.
55.
A. G. Shavva G. L. Starova S. I. Selivanov S. N. Morozkina 《Chemistry of Heterocyclic Compounds》2008,44(2):148-152
By X-ray crystallographic analysis and NMR spectroscopy it was demonstrated that the conformations of several D-homo-6-oxa-8α
analogs of steroidal estrogens are similar in the crystal and in solution. The distances between the hydrogen atoms in these
molecules, calculated by the ab initio and MM+ methods, correspond to the experimental data.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 202–207, February, 2008. 相似文献
56.
Hyung-Geun Moon You-Sun Kim Jun-Pyo Choi Dong-Sic Choi Chang Min Yoon Seong Gyu Jeon Yong Song Gho Yoon-Keun Kim 《Experimental & molecular medicine》2010,42(1):47-60
Theophylline is commonly used to treat severe asthma and chronic obstructive pulmonary disease (COPD) characterized by non-eosinophilic inflammation. Acetyl salicylic acid (ASA) is one of the most widely used medications worldwide, but up to 20% of patients with asthma experience aggravated respiratory symptoms after taking ASA. Here we evaluated the adverse effect of ASA on the therapeutic effect of theophylline in mice with non-eosinophilic asthma. A non-eosinophilic asthma mouse model was induced by airway sensitization with lipopolysaccharide-containing allergen and then challenged with allergen alone. Therapeutic intervention was performed during allergen challenge. Theophylline inhibited lung inflammation partly induced by Th1 immune response. ASA attenuated the beneficial effects of theophylline. However, co-administration of the ASA metabolite salicylic acid (SA) showed no attenuating effect on theophylline treatment. The therapeutic effect of theophylline was associated with increase in cAMP levels, which was blocked by co-treatment of theophylline and ASA. ASA co-treatment also attenuated the anti-inflammatory effects of a specific phosphodiesterase 4 inhibitor. These results demonstrate that ASA reverses anti-inflammatory effects of theophylline, and that ASA exerts its adverse effects through the inhibition of cAMP production. Our data suggest that ASA reverses lung inflammation in patients taking theophylline, although clinical evidence will be needed. 相似文献
57.
用 R T P C R技术从 C S F V H C L V 株 F482 代感染兔脾的细胞总 R N A 中分段扩增出了 C S F V E2 基因特异的3 个部分重叠的 D N A 片段(大小分别为 499 bp、572 bp 和 245 bp),并将之分别克隆到p G E M T 载体上 经核苷酸序列测定和片段重叠完成了包含 E2 全长基因的 1 144 bp 序列的测定,其 G C含量为49.0% :核苷酸序列与国外报道的各株病毒的 E2 基因同源性分别为83.5% ~97.5% ;其推导的氨基酸序列的同源性也分别为89.3%~96.2% ,变异主要分布在 E2 蛋白的 N 半部分 相似文献
58.
Yaghoub Haghighatnia Saeed Balalaie Hamid Reza Bijanzadeh 《Helvetica chimica acta》2012,95(5):818-824
Some new amidated fentanyl (=N‐[1‐(2‐phenylethyl)piperidin‐4‐yl]‐N‐phenylpropanamide) analogs with a 4‐(N‐phenylamido)piperidine scaffold and additional amide bonds have been designed and synthesized through Ugi four‐component reaction (Ugi‐4CR). Good‐to‐high yields, diversity‐oriented synthesis, and possible applications in drug discovery are advantages of this approach. 相似文献
59.
冠心病患者尽管接受了标准的氯吡格雷治疗,但仍有一部分患者对氯吡咯雷表现为低反应甚至无反应,称为氯吡格雷抵抗。导致这种抵抗现象的可能原因包括患者个体的基因多态性和药物之间的相互作用等。临床处理的主要对策有提高氯吡格雷的给药剂量和采用新型药物等。笔者就现有的临床研究证据对氯吡格雷抵抗的定义、发生机制及临床干预策略进行了综述。 相似文献
60.