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181.
Moon HR Lee KM Lee JH Lee SK Park SB Chun MW Jeong LS 《Nucleosides, nucleotides & nucleic acids》2005,24(5-7):707-708
Four 5'-substituted fluoro-neplanocin A analogues la-d were designed and synthesized, and the inhibitory activity against SAH was in the following order: NH2 > SH > F, N3, indicating a hydrogen bonding donor is essential for inhibitory activity. 相似文献
182.
A study was conducted to determine the efficacy of β-mannanase supplementation to a diet based on corn and soya bean meal (SBM) on growth performance, nutrient digestibility, blood urea nitrogen (BUN), faecal coliforms and lactic acid bacteria, and noxious gas emission in growing pigs. A total of 140 pigs [(Landrace × Yorkshire) × Duroc; average body weight 25 ± 3 kg] were randomly allotted to a 2 × 2 factorial arrangement with dietary treatments consisting of hulled or dehulled SBM without or with supplementation of 400 U β-mannanase/kg. During the 6 weeks of experimental feeding, β-mannanase supplementation had no effect on body weight gain, feed intake and gain:feed (G:F) ratio. Compared with dehulled SBM, feeding hulled SBM caused an increased feed intake of pigs in the entire trial (p = 0.05). The G:F ratio was improved in pigs receiving dehulled SBM (p < 0.05). Dietary treatments did not influence the total tract digestibility of dry matter, nitrogen and gross energy. Enzyme supplementation reduced (p < 0.05) the population of faecal coliforms and tended to reduce the NH3 concentration after 24 h of fermentation in a closed box containing faecal slurry. Feeding hulled SBM tended to reduce NH3 emission on days 3 and 5 of fermentation. In conclusion, mannanase supplementation had no influence on growth performance and nutrient digestibility but showed a positive effect on reducing coliform population and tended to reduce NH3 emission. Dehulled SBM increased G:F ratio and hulled SBM tended to reduce NH3 emission. 相似文献
183.
Hye Ran Park Jae Meen Lee Gwanhee Ehm Hui-Jun Yang In Ho Song Yong Hoon Lim Mi-Ryoung Kim Keyoung Ran Kim Woong-Woo Lee Young Eun Kim Jae Ha Hwang Chae Won Shin Hyeyoung Park Jin Wook Kim Han-Joon Kim Cheolyoung Kim Dong Gyu Kim Beom Seok Jeon Sun Ha Paek 《PloS one》2016,11(1)
Background
GPi (Internal globus pallidus) DBS (deep brain stimulation) is recognized as a safe, reliable, reversible and adjustable treatment in patients with medically refractory dystonia.Objectives
This report describes the long-term clinical outcome of 36 patients implanted with GPi DBS at the Neurosurgery Department of Seoul National University Hospital.Methods
Nine patients with a known genetic cause, 12 patients with acquired dystonia, and 15 patients with isolated dystonia without a known genetic cause were included. When categorized by phenomenology, 29 patients had generalized, 5 patients had segmental, and 2 patients had multifocal dystonia. Patients were assessed preoperatively and at defined follow-up examinations postoperatively, using the Burke-Fahn-Marsden dystonia rating scale (BFMDRS) for movement and functional disability assessment. The mean follow-up duration was 47 months (range, 12–84)Results
The mean movement scores significantly decreased from 44.88 points preoperatively to 26.45 points at 60-month follow up (N = 19, P = 0.006). The mean disability score was also decreased over time, from 11.54 points preoperatively to 8.26 points at 60-month follow up, despite no statistical significance (N = 19, P = 0.073). When analyzed the movement and disability improvement rates at 12-month follow up point, no significant difference was noted according to etiology, disease duration, age at surgery, age of onset, and phenomenology. However, the patients with DYT-1 dystonia and isolated dystonia without a known genetic cause showed marked improvement.Conclusions
GPi DBS is a safe and efficient therapeutic method for treatment of dystonia patients to improve both movement and disability. However, this study has some limitations caused by the retrospective design with small sample size in a single-center. 相似文献184.
Kyung-Ho Ma Anupam Dixit Young-Chang Kim Dong-Yun Lee Tae-San Kim Eun-Gi Cho Yong-Jin Park 《Conservation Genetics》2007,8(6):1507-1509
Panax ginseng C.A. Meyer, commonly known as Korean or Asian ginseng, is a perennial herb native to Korea and China. Its roots are highly
prized for several medicinal properties. The present study describes development and characterization of twenty-two polymorphic
microsatellite markers for this species. A total of 99 alleles were detected with an average of 4.5 alleles per locus across
20 accessions. Values for observed (H
O
) and expected (H
E
) heterozygosities ranged from 0.05 to 1.00 and from 0.18 to 0.73, respectively. Eleven loci deviated from Hardy–Weinberg
equilibrium (P < 0.001). Significant (P < 0.05) heterozygote deficiency was observed at 13 loci. Exact test for linkage disequilibrium showed significant values
(P < 0.05) between 12 pairs of loci. These microsatellite markers provide powerful tools for understanding population and conservation
genetics of this species and also for genetic differentiation and authentication of different Panax species being used in commercial ginseng products. 相似文献
185.
Cho Y Shin YH Kim Y Kim H Lee Y Park E Fuchs JA Lim C 《Biochimica et biophysica acta》2001,1518(1-2):194-199
A cDNA coding thioredoxin (TRX) was isolated from a cDNA library of Schizosaccharomyces pombe by colony hybridization. The 438 bp EcoRI fragment, which was detected by Southern hybridization, reveals an open reading frame which encodes a protein of 103 amino acids. The genomic DNA encoding TRX was also isolated from S. pombe chromosomal DNA using PCR. The cloned sequence contains 1795 bp and encodes a protein of 103 amino acids. However, the C-terminal region obtained from the cDNA clone is -Val-Arg-Leu-Asn-Arg-Ser-Leu, whereas the C-terminal region deduced from the genomic DNA appears to contain -Ala-Ser-Ile-Lys-Ala-Asn-Leu. This indicates that S. pombe cells contain two kinds of TRX genes which have dissimilar amino acid sequences only at the C-terminal regions. The heterologous TRX 1C produced from the cDNA clone could be used as a subunit of T7 DNA polymerase, while the TRX 1G from the genomic DNA could not. The upstream sequence and the region encoding the N-terminal 18 amino acids of the genomic DNA were fused into the promoterless beta-galactosidase gene of the shuttle vector YEp357 to generate the fusion plasmid pYKT24. Synthesis of beta-galactosidase from the fusion plasmid was found to be enhanced by hydrogen peroxide, menadione and aluminum chloride. It indicates that the expression of the cloned TRX gene is induced by oxidative stress. 相似文献
186.
Pain is a fundamental experience with a complex and multi-layered neurobiological basis. In recent years a powerful battery of techniques has been brought to bear to unravel the mechanisms by which painful stimuli are transduced and processed. There have been several recent discoveries regarding the molecular transduction mechanisms in nociceptors and novel molecular and cellular mechanisms underlying the spinal processing of painful stimuli. The mechanisms by which sensory neurons initiate hyperalgesia and touch evoked pain (allodynia) have been addressed particularly successfully in recent studies. The rich variety of key molecular players that have emerged in physiological and pathophysiological pain states reflects the sophistication and uniqueness of this vitally important sense. 相似文献
187.
188.
Living cells orient the cytoskeleton polarity and directional migration in response to spatial gradients of multiple types of cues. The resulting tactic behaviors are critical for the proper cell localization in the context of complex single-cell and tissue behaviors. In this perspective, we highlight the recent discovery of, to our knowledge, a new -taxis phenomenon, the topotaxis, which mediates directional cell migration in response to the gradients of such topographic features as the density of extracellular matrix fibers. The direction of topotactic migration critically depends on the effective stiffness of the cortical cytoskeleton, which is controlled by the balance between two parallel signaling pathways activated by the extracellular matrix input. Topotaxis can account for such striking cell behaviors as the opposite directionality of migration of benign and metastatic cancer cells and certain aspects of the wound-healing process. We anticipate that, in conjunction with other tactic phenomena, topotaxis can provide critical information for understanding and design of tissue structure and function. 相似文献
189.
Jangsup Moon Soon-Tae Lee Jiye Choi Keun-Hwa Jung Hyunwoo Yang Arshi Khalid Jeong-Min Kim Kyung-Il Park Jung-Won Shin Jae-Jun Ban Gwan-Su Yi Sang Kun Lee Daejong Jeon Kon Chu 《PloS one》2014,9(1)