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91.
92.
A series of chiral pyrrolidine-sulfamides were prepared and examined as the catalysts for conjugate addition of ketones to nitroalkenes. Benzoic acid was identified as the most efficient additives for the transformation. Excellent enantioselectivities, diastereoselectivities, and yields were achieved for the reaction of cyclohexanone with β-aryl nitroethylenes under solvent free conditions. β-Isopropyl nitroethylene is also applicable and the product could be obtained with excellent enantioselectivity after extended reaction time. A comparison of the catalytic behaviors of pyrrolidine-sulfamide organocatalysts with different side chains demonstrates that the enantioselectivity is mainly controlled by the chiral pyrrolidine unit and the additional chiral center at the side chain exerts neglectable effects. The H-bonding interaction between the sulfamide and the nitro group is proposed to be crucial for the activation of the nitroalkene and the constitution of well-organized transition state. 相似文献
93.
Enantioselective degradation of warfarin in soils 总被引:1,自引:0,他引:1
94.
Isabel Mendizabal Oscar Lao Urko M. Marigorta Andreas Wollstein Leonor Gusmão Vladimir Ferak Mihai Ioana Albena Jordanova Radka Kaneva Anastasia Kouvatsi Vaidutis Kučinskas Halyna Makukh Andres Metspalu Mihai G. Netea Rosario de Pablo Horolma Pamjav Dragica Radojkovic Sarah J.H. Rolleston Jadranka Sertic Milan Macek Manfred Kayser 《Current biology : CB》2012,22(24):2342-2349
95.
96.
Kaeriyama M Machida K Kitakaze A Wang H Lao Q Fukamachi T Saito H Kobayashi H 《Letters in applied microbiology》2006,42(3):195-201
AIMS: To investigate the requirement of outer membrane porins for osmotic adaptation at alkaline pH in Escherichia coli. METHODS AND RESULTS: Escherichia coli mutants deficient in ompC, ompF and both genes were constructed and the growth of these mutants was observed at alkaline pH. The growth rate of the mutant deficient in both ompC and ompF was slower than that of the wild type and mutants deficient in one of these genes under hyperosmotic stress at pHs above 8.0. The decreased rate was recovered when a cloned ompC was introduced to the mutant, but the growth recovery with a cloned ompF was partial. Such growth diminution was not observed at pHs below 8.0. CONCLUSION: OmpC and OmpF were shown to participate in hyperosmotic adaptation at alkaline pH in E. coli. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first report to demonstrate that OmpC and OmpF are required for hyperosmotic adaptation at pHs above 8.0, but not below 8.0. 相似文献
97.
Ren SP Wu CT Huang WR Lu ZZ Jia XX Wang L Lao MF Wang LS 《Cancer immunology, immunotherapy : CII》2006,55(4):375-385
Multiple myeloma (MM) remains incurable despite the use of high-dose chemotherapy and stem cell transplantation. However,
immunotherapy is expected to offer long-term disease control, or even possibly a cure. We have previously demonstrated the
suppressive effect of a recombinant adenovirus carrying human wild-type p53, granulocyte–macrophage colony-stimulating factor,
and B7-1 genes (Ad-p53/GM-CSF/B7-1) on the growth of laryngeal cancer cells. In the present study, we evaluated the effects
of an Ad-p53/GM-CSF/B7-1-modified myeloma cell vaccine strategy aimed to induce apoptosis and to augment the immunogenicity
of MM cells. Both MM cell lines and purified primary myeloma cells were infected with Ad-p53/GM-CSF/B7-1. High expression
levels of these three genes were confirmed separately by Western blot, enzyme-linked immunosorbent assay (ELISA), and flow
cytometry. When wild-type p53, GM-CSF and B7-1 genes were introduced, the growth of MM cells was inhibited via enhanced apoptosis
and the immunogenicity of tumor cells was augmented. The combinatorial effect of these three genes on inducing cytotoxic T
lymphocytes (CTLs) was more evident than that of p53 individually or any combinations of two (p53 plus GM-CSF or p53 plus
B7-1). Furthermore, significant proliferation of autologous peripheral blood lymphocytes (PBLs) and specific cytotoxicity
against autologous primary MM cells were induced in vitro. These results suggest that myeloma cell vaccination co-transferred
with p53, GM-CSF and B7-1 genes may be a promising immunotherapeutic approach against MM. 相似文献
98.
99.
Ihor E. Kopka Linus S. Lin James P. Jewell Thomas J. Lanza Tung M. Fong Chun-Pyn Shen Zhege J. Lao Sookhee Ha Laurie G. Castonguay Lex Van der Ploeg Mark T. Goulet William K. Hagmann 《Bioorganic & medicinal chemistry letters》2010,20(16):4757-4761
The design, synthesis, and binding activity of ring constrained analogs of the acyclic cannabinoid-1 receptor (CB1R) inverse agonist taranabant 1 are described. The initial inspiration for these taranabant derivatives was its conformation 1a, determined by 1H NMR, X-ray, and molecular modeling. The constrained analogs were all much less potent than their acyclic parent structure. The results obtained are discussed in the context of a predicted binding of 1 to a homology model of CB1R. 相似文献
100.
Here we describe a protocol for the detection of the microRNA (miRNA) expression profile of a single cell by stem-looped real-time PCR, which is specific to mature miRNAs. A single cell is first lysed by heat treatment without further purification. Then, 220 known miRNAs are reverse transcribed into corresponding cDNAs by stem-looped primers. This is followed by an initial PCR step to amplify the cDNAs and generate enough material to permit separate multiplex detection. The diluted initial PCR product is used as a template to check individual miRNA expression by real-time PCR. This sensitive technique permits miRNA expression profiling from a single cell, and allows analysis of a few cells from early embryos as well as individual cells (such as stem cells). It can also be used when only nanogram amounts of rare samples are available. The protocol can be completed in 7 d. 相似文献