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991.
A L Olins B A Moyer S H Kim D P Allison 《The journal of histochemistry and cytochemistry》1989,37(3):395-398
Specific DNA staining for electron microscopic observation is simplified by a shorter synthesis of the staining reagent. The new, more reliable reagent, osmium ammine-B, is stable for more than a year, dissolves completely in water, and does not require reoptimization of staining conditions for every batch, yet reproducibly gives strong contrast to DNA-containing structures. 相似文献
992.
M H Kim R Nakayama P Manos J E Tomlinson E Choi J D Ng D Holten 《Journal of lipid research》1989,30(5):663-671
Rats were fasted or fasted and refed simple purified diets so the effects of individual carbohydrates or fats could be studied. Freshly isolated hepatocytes from these animals were used to measure both apoE synthesis and mRNA levels so any changes in apoE synthesis that might occur without changes in its mRNA could be detected. Some of these experiments were done with both sexes. Both fasting and fasting and refeeding a 60% glucose fat-free diet significantly increased spoE synthesis. However, cyclic AMP is not likely to rapidly mediate the effect of fasting since dibutyryl cAMP slightly lowered (rather than increased) apoE synthesis and mRNA when injected into rats for 4.5 h. Dietary fat had no effect either in the absence of carbohydrate or when consumption of carbohydrate was constant in pair-fed rats. ApoE mRNA levels remained normal for 4 days in primary hepatocytes cultured in medium that had only amino acids as an energy source. Added hormones or fructose had no significant effect. Thus, only fasting and fasting and refeeding glucose were able to significantly change apoE synthesis or mRNA levels. Synthesis of apoE may be regulated to increase when apoE is secreted with very low density lipoprotein or when apoE in secreted high density lipoprotein is needed to acquire cholesteryl esters for the synthesis of bile salts and acids by liver. 相似文献
993.
Differential effects of phencyclidine (PCP) and ketamine on mesocortical and mesostriatal dopamine release in vivo 总被引:4,自引:0,他引:4
The interactions of phencyclidine (PCP) with the mesocortical dopaminergic system were of interest because of the putative role of this pathway in the etiology of schizophrenia. In the present investigation we examined the effects of PCP, and PCP-receptor agonist, ketamine, on dopamine (DA) release by measuring the levels of 3-methoxytyramine (3-MT), the only DA metabolite which is a reliable indicator of DA release in vivo. PCP increased DA release in the amygdala, pyriform and prefrontal cortices, while ketamine was less potent than PCP in this respect. In contrast to the changes in DA release in the cortical regions, ketamine decreased DA release in striatum, while PCP did not change DA release. 相似文献
994.
So Yung Yang Ji Hyun Baek Youngah Cho Eun-Young Cho Yujin Choi Yongkang Kim 《Chronobiology international》2018,35(3):405-415
ST8SIA2 and NCAM1 are functionally related genes forming polysialic acid (PSA) - neural cell adhesion molecule (NCAM) complex in suprachiasmatic nucleus (SCN), the regulating site of circadian biological rhythm. In this study, the relationship of ST8SIA2 and NCAM1 with circadian and seasonal rhythms of human behavior was explored. Subjects were 261 healthy Korean adults who were free of any history of clinically significant psychiatric symptoms. The phenotypes were circadian preference and seasonal change of mood and behavior (seasonality) measured by the Composite Scale of Morningness and the Seasonal Pattern Assessment Questionnaire, respectively. Thirty-four single nucleotide polymorphisms (SNPs) across the ST8SIA2 region and 15 SNPs of NCAM1 were analyzed. A nominally significant association with seasonality and circadian preference was observed in 21 variants of both genes. After corrections for multiple testing, associations of 8 SNPs of ST8SIA2 and 2 SNPs of NCAM1 with seasonality remained significant. Some of these SNPs were also associated with psychiatric disorders in previous studies. This study demonstrated a meaningful and/or suggestive evidence of association between behavioral phenotypes reflecting human biological rhythm and two interplaying genes involved in the plasticity of SCN’s neuronal network. 相似文献
995.
Gonadal development and sexual maturation of fish are often related to photic conditions. We attempted to utilise the direct application of melatonin to elicit similar effects in the absence of photoperiod manipulation. We found no significant differences in somatic growth between melatonin-treated groups and controls, indicating that melatonin administration did not negatively affect the growth of the experimental fish. Treatment with low-dose melatonin (0.3 mg/kg BW) resulted in a decrease in spawning frequency, number of spawned eggs and gonadosomatic index in female tilapia. In male tilapia, low-dose melatonin was associated with a decrease in sperm count, spermatocrit and spermatozoa activity index, implying that exogenous melatonin might mimic the effects of shortened light photoperiod, which suppresses reproductive activity in this species. These results suggest the possibility that an optimised dose of melatonin treatment could be used to control the spawning behaviour of this species. 相似文献
996.
997.
Joo-Hyun Seo Won-Ki Min Seung-Geun Lee Hyungdon Yun Byung-Gee Kim 《Biotechnology and Bioprocess Engineering》2018,23(2):134-143
Directed evolution of proteins is a good approach to develop desired phenotypes from existing proteins. Fully experimental protein evolution usually utilizes randomization of a given protein sequence by error-prone PCR or gene shuffling followed by high-throughput selection or timeconsuming screening method. However, these random methods create mutant library full of deleterious mutations. In addition, they need high-throughput screening or selection method to search for positive clones from an enormous size of mutant library. Construction of a mutant library while retaining the original function is important for efficient protein evolution because it greatly reduces time and effort for the identification of positive mutants. Therefore, researchers have tried to reduce the size of mutant library by minimizing the occurrence of deleterious mutants. Such efforts have led to the creation of a concept of ‘small but smart library’. For this goal, neutral drift theory has been applied. Although smart library greatly reduces the library size, it is still the beyond the capacity of low-throughput assay. In parallel, computational analysis of protein structure and efforts to discriminate mutatable residues from all residues of a given protein have been consistently pursued. Accumulated knowledge of protein evolution through random mutation and selection has improved our understanding of functions of amino acids in protein structure. Protein evolution by rational design is being developed based on such understanding. In this review, we describe how the use of semi-rationally designed library rather than completely random one has impacted the overall procedure of directed evolution. We also describe efforts made to evaluate the effect of single mutation. Such efforts will bring lazy boys to the final goal - computational mutation suggestion system. 相似文献
998.
Kim Allen 《Ethnic and racial studies》2018,41(13):2301-2309
Foregrounding the voices of minority women in England, Scotland and France, Minority Women and Austerity provides a rich and compelling account of austerity’s lived effects. Through its intersectional analyses and historically attendant frame, the book locates minority women’s experiences of austerity not as fundamentally “new” but rather as an extension and sharpening of conditions of “routinized crisis” and inequality. In doing so it compels its readers to ask: whose crisis counts? In this review paper, I summarize the book’s key contributions. In particular, I discuss the book’s theorizations of “political racelessness” to critique the erasure of minority women’s experiences and activism. I reflect on what this means for those researching austerity and its deleterious effects, and for those participating in anti-austerity activism. I end by discussing the analytical tools that the book offers for interrogating the Left’s response to on-going austerity within a post-Brexit Britain. 相似文献
999.
Lee Joo-Hyoung Park Jong-Ho Park Sun-Hye Kim Sun-Hong Kim Jee Yon Min Jeong-Ki Lee Gyun Min Kim Yeon-Gu 《Applied microbiology and biotechnology》2018,102(11):4729-4739
Applied Microbiology and Biotechnology - Despite the relatively low transfection efficiency and low specific foreign protein productivity (qp) of Chinese hamster ovary (CHO) cell-based transient... 相似文献
1000.
Kang Yerin Lee Woonwoo Jang Geupil Kim Bong-Gyu Yoon Youngdae 《Applied microbiology and biotechnology》2018,102(11):4863-4872
Applied Microbiology and Biotechnology - Despite the large number of bioreporters developed to date, the ability to detect heavy metal(loid)s with bioreporters has thus far been limited owing to... 相似文献