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排序方式: 共有4358条查询结果,搜索用时 15 毫秒
1.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):837-839
Abstract Some diacid biodegradable synthesis of aziduthymidine (AZT) were synthesized and applied to production of about 60 different derivatives. 相似文献
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Scott A. Kleiner 《Biology & philosophy》1999,14(1):55-63
Thomas Nickles challenges my thesis that innovative discoveries can be based on deliberately chosen problems and research strategies. He suggests that all significant innovation can be seen as such only in retrospect and that its generation must be serendipitous. Here I argue in response that significant innovations can and do often arise from self conscious critical appraisal of orthodox practice combined with regulated though speculative abductive argumentation to alternative explanatory schemata. Orthodox practice is not based upon monolithic systems of belief about the subject of inquiry. Rather major domains of scientific practice often are approached from different conceptualizations that provide grounds for critical dialectic and consilient empirical information. Abductive arguments that meet appropriate conditions of likelihood, probability and analogy are an important means of justifying allocating resources to innovative practices that have yet to produce products that can rival those of established orthodoxy. 相似文献
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Ruth Duncan Pavla Rejmanova Jindrich Kopeček John B. Lloyd 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,678(1):143-150
Synthetic 125I-labelled N-(2-hydroxypropyl)methacrylamide copolymers containing four different, potentially degradable peptidyl side chains were incubated with rat visceral yolk sacs cultured in vitro. All copolymers were captured by fluid-phase pinocytosis and three of the side chains were susceptible to lysosomal hydrolysis, resulting in release of [125I]iodotyrosine back into the culture medium. Uptake and degradation was completely inhibited by 2,4-dinitrophenol. The thiol-proteinase inhibitor leupeptin did not affect the rate of pinocytosis, but caused different degrees of inhibition of hydrolysis depending on side chain composition. 相似文献
6.
Reactive oxygen species (ROS) are involved in the pathophysiology of fulminant hepatic failure. Therefore, we developed polyethylene glycol-conjugated bovine serum albumin with multiple reduced thiols (PEG-BSA-SH) for the treatment of fulminant hepatic failure. As a long-circulating ROS scavenger, PEG-BSA-SH effectively scavenged highly reactive oxygen species and hydrogen peroxide in buffer solution. PEG-BSA-SH showed a long circulation time in the plasma after intravenous injection into mice. Fulminant hepatic failure was induced by intraperitoneal injection of lipopolysaccharide and d-galactosamine (LPS/d-GalN) into mice. The LPS/d-GalN-induced elevation of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels was significantly inhibited by a bolus intravenous injection of PEG-BSA-SH. Furthermore, the changes in hepatic lipid peroxide and hepatic blood flow were effectively suppressed by PEG-BSA-SH. In contrast, l-cysteine, glutathione, and dithiothreitol, three traditional reduced thiols, had no statistically significant effects on the serum levels of ALT or AST. These findings indicate that PEG-BSA-SH is a promising ROS scavenger and useful in the treatment of fulminant hepatic failure. 相似文献
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Lars Terenius Björn Johansson 《Biochemical and biophysical research communications》2010,396(1):140-142
This mini-review outlines the opioid systems and their roles primarily as related to reward and compulsive drug/alcohol intake. The central role is taken by the mu-opioid receptor, target for opiate analgesics and also a central target in compulsive alcohol abuse, alcoholism. The mu-opioid receptor and the cognate opioid neuropeptides from proenkephalin and proopiomelancortin are members of a superfamily of opioid systems, each with unique and still to be defined roles in the central nervous system. 相似文献
9.
Changsung Kim 《BMB reports》2015,48(5):256-265
Cardiovascular and neurodegenerative diseases are major health threats in many
developed countries. Recently, target tissues derived from human embryonic stem
(hES) cells and induced pluripotent stem cells (iPSCs), such as cardiomyocytes
(CMs) or neurons, have been actively mobilized for drug screening. Knowledge of
drug toxicity and efficacy obtained using stem cell-derived tissues could
parallel that obtained from human trials. Furthermore, iPSC disease models could
be advantageous in the development of personalized medicine in various parts of
disease sectors. To obtain the maximum benefit from iPSCs in disease modeling,
researchers are now focusing on aging, maturation, and metabolism to
recapitulate the pathological features seen in patients. Compared to pediatric
disease modeling, adult-onset disease modeling with iPSCs requires proper
maturation for full manifestation of pathological features. Herein, the success
of iPSC technology, focusing on patient-specific drug treatment,
maturation-based disease modeling, and alternative approaches to compensate for
the current limitations of patient iPSC modeling, will be further discussed.
[BMB Reports 2015; 48(5): 256-265] 相似文献
10.
Wei Liu Yaoting Sun Weigang Ge Fangfei Zhang Lin Gan Yi Zhu Tiannan Guo Kexin Liu 《Molecular & cellular proteomics : MCP》2022,21(2):100187
Drug resistance is a critical obstacle to effective treatment in patients with chronic myeloid leukemia. To understand the underlying resistance mechanisms in response to imatinib mesylate (IMA) and adriamycin (ADR), the parental K562 cells were treated with low doses of IMA or ADR for 2 months to generate derivative cells with mild, intermediate, and severe resistance to the drugs as defined by their increasing resistance index. PulseDIA-based (DIA [data-independent acquisition]) quantitative proteomics was then employed to reveal the proteome changes in these resistant cells. In total, 7082 proteins from 98,232 peptides were identified and quantified from the dataset using four DIA software tools including OpenSWATH, Spectronaut, DIA-NN, and EncyclopeDIA. Sirtuin signaling pathway was found to be significantly enriched in both ADR-resistant and IMA-resistant K562 cells. In particular, isocitrate dehydrogenase (NADP(+)) 2 was identified as a potential drug target correlated with the drug resistance phenotype, and its inhibition by the antagonist AGI-6780 reversed the acquired resistance in K562 cells to either ADR or IMA. Together, our study has implicated isocitrate dehydrogenase (NADP(+)) 2 as a potential target that can be therapeutically leveraged to alleviate the drug resistance in K562 cells when treated with IMA and ADR. 相似文献