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排序方式: 共有3751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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Claire Pickard 《Bioethics》2020,34(2):207-210
A recent article argued for the immorality of abortion regardless of personhood status by comparing the impairment caused by fetal alcohol syndrome to the impairment caused by abortion. I argue that two of the premises in this argument fail and that, as such, one cannot reasonably attribute moral harms to abortion on the basis of the moral harms caused by fetal alcohol syndrome. The impairment argument relies on an inconsistent instantiation, which undermines the claim that personhood is irrelevant, and it does not fulfill its own ceteris paribus clause, which demands that no additional benefit be gained from abortion that would not be gained from causing fetal alcohol syndrome. 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
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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
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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
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Summary
Dalbergia sissoo, a wind-dispersed tropical tree, shows a positively skewed distribution of seeds per pod. This is attributed to the enhanced dispersal advantage of few-seeded pods due to their reduced wing loading (ratio of weight to pod surface area) and low settling velocity. The proximate mechanisms causing the positively skewed distribution were investigated. The distribution could not be attributed to the distribution pattern of ovule number per ovary, pollen grain limitation, lack of ovule fertilization, or post-fertilization elimination of many-seeded pods. Rather, it was caused by the post-fertilization abortion of seeds within a pod 2 weeks after fertilization. This intra-pod seed abortion (IPSA) is due to a dominance hierarchy of fertilized ovules from the distal (near stigma) to the basal end, generated by the temporal differences in fertilization. The dominant developing seeds at the distal end cause the abortion of others through the production and diffusion of an aborting agent. When the dominance hierarchy of the siblings is not intense, pods are formed with more than one seed. We argue that the positively skewed distribution of seeds per pod is not due to maternal regulation but is a result of sibling rivalry. We propose that this sibling rivalry is generated by genetic differences in pollen grain fitness and disucss the results in the context of parent-offspring conflict. 相似文献