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排序方式: 共有2667条查询结果,搜索用时 31 毫秒
51.
Chun Pil Choi Seon Mi Yim Soo Hong Seo Hyo Hyun Ahn Young Chul Kye 《Journal of cosmetic and laser therapy》2015,17(3):129-134
Background: Aggravated melasma after treatment is vulnerable to stimulation, can easily deteriorate, and may be distressing without proper management. Objective: To retrospectively assess the effectiveness and safety of combination therapy using low-fluence Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (QSNY) and long-pulse Nd:YAG laser (LPNY) (dual toning) in patients with rebound melasma. Materials and methods: A total of 30 patients with aggravated melasma after previous therapy who were treated with dual toning were enrolled. A total of 10 sessions were conducted at 1-week intervals, followed by maintenance treatment. The results were evaluated using the modified Melasma Area and Severity Index (mMASI) and the physician's global assessment (PGA) before and 2 months after completing the 10 treatment sessions. Results: The baseline mMASI was 10.48 ± 3.64, which significantly decreased to 3.22 ± 1.45 2 months after completing the 10 treatment sessions (p < 0.001). Twenty-four patients (80%) had PGA grade 4 (76–100% improvement) and 6 patients (20%) had PGA grade 3 (51–75% improvement). Conclusion: Dual toning may be a safe and effective salvage treatment for patients with aggravated melasma after previous treatment. LPNY may stabilize melasma activity to prevent rebound hyperpigmentation via dermal remodeling. 相似文献
52.
Reduced risk of hepatocellular carcinoma by achieving a subcirrhotic liver stiffness through antiviral agents in hepatitis B virus‐related advanced fibrosis or cirrhosis 下载免费PDF全文
53.
Andrea Choe Tatsuji Chuman Stephan H. von Reuss Aaron T. Dossey Joshua J. Yim Ramadan Ajredini Adam A. Kolawa Fatma Kaplan Hans T. Alborn Peter E. A. Teal Frank C. Schroeder Paul W. Sternberg Arthur S. Edison 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(51):20949-20954
Nematodes use an extensive chemical language based on glycosides of the dideoxysugar ascarylose for developmental regulation (dauer formation), male sex attraction, aggregation, and dispersal. However, no examples of a female- or hermaphrodite-specific sex attractant have been identified to date. In this study, we investigated the pheromone system of the gonochoristic sour paste nematode Panagrellus redivivus, which produces sex-specific attractants of the opposite sex. Activity-guided fractionation of the P. redivivus exometabolome revealed that males are strongly attracted to ascr#1 (also known as daumone), an ascaroside previously identified from Caenorhabditis elegans hermaphrodites. Female P. redivivus are repelled by high concentrations of ascr#1 but are specifically attracted to a previously unknown ascaroside that we named dhas#18, a dihydroxy derivative of the known ascr#18 and an ascaroside that features extensive functionalization of the lipid-derived side chain. Targeted profiling of the P. redivivus exometabolome revealed several additional ascarosides that did not induce strong chemotaxis. We show that P. redivivus females, but not males, produce the male-attracting ascr#1, whereas males, but not females, produce the female-attracting dhas#18. These results show that ascaroside biosynthesis in P. redivivus is highly sex-specific. Furthermore, the extensive side chain functionalization in dhas#18, which is reminiscent of polyketide-derived natural products, indicates unanticipated biosynthetic capabilities in nematodes. 相似文献
54.
J. H. Kim H. J. Yim E. S. Jung Y. K. Jung J. H. Kim Y. S. Seo J. E. Yeon H. S. Lee S. H. Um K. S. Byun 《Journal of viral hepatitis》2011,18(4):287-293
Summary. Clevudine shows high rates of virologic and biochemical responses in patients with chronic hepatitis B. However, the efficacy and safety of clevudine in patients with cirrhosis are unknown. The aims of this study were to evaluate the safety and to assess the virologic and the biochemical responses to clevudine in patients with cirrhosis with chronic hepatitis B virus (HBV) infection. We reviewed data from treatment‐naïve patients with chronic hepatitis B with and without cirrhosis who started clevudine between April 2007 and March 2008 (n = 52, hepatitis B without cirrhosis n = 21 and chronic hepatitis B with cirrhosis n = 31) at Korea University Ansan/Guro Hospital. All of the patients were treated for more than 48 weeks. The mean age was older in the patients with cirrhosis. Baseline HBV DNA levels were 6.9 and 7.78 log copies/mL (P = 0.042), and alanine aminotransferase (ALT) levels were 104.9 and 147.4 IU/L (P = 0.204), for those with and without cirrhosis, respectively. Virologic response (HBV DNA <1000 copies/mL) (87.1%vs 71.4%, P = 0.24) and biochemical response (83.9%vs 80.9%, P = 0.99) at week 48 were not significantly different between the two groups. Early virologic response at week 12 was even higher in the patients with cirrhosis (61.3%vs 28.6%, P = 0.026). Neither ALT flare nor newly onset hepatic decompensation was found in the patients with cirrhosis, whereas ALT flare was transiently observed in 14.3% of the chronic hepatitis group. In conclusion, although clevudine may produce a transient elevation of ALT during the early treatment period, such findings were not observed in patients with cirrhosis and the virologic and biochemical responses of the groups were comparable. 相似文献
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57.
Jeff SW Wong Calvin SH Ng Tak Wai Lee Anthony PC Yim 《Canadian respiratory journal》2006,13(4):219-221
The present report describes a case of severe airway obstruction caused by endobronchial tuberculosis in an 11-year-old girl who was successfully treated by bronchoscopic balloon dilation. This case illustrates the insidious presentation and the increasingly important role of bronchoscopic intervention in the management of endobronchial tuberculosis. In addition, a brief literature review of the condition in the pediatric age group is included. 相似文献
58.
Rearrangement of the T cell receptor gamma-chain gene in childhood acute lymphoblastic leukemia 总被引:4,自引:0,他引:4
We analyzed rearrangements of the T cell receptor gamma-chain (T gamma) gene as well as rearrangements of the T cell receptor beta-chain (T beta) gene and immunoglobulin heavy-chain (IgH) gene in 68 children with acute lymphoblastic leukemia (ALL). All 15 patients with T cell ALL showed rearrangements of both T beta and T gamma genes. Twenty-four of 53 non-T, non-B ALL patients (45%) showed T gamma gene rearrangements and only 14 of these also showed T beta gene rearrangements. Only a single patient rearranged the T beta gene in the absence of T gamma gene rearrangement. The rearrangement patterns of the T gamma gene in non-T, non-B ALL were quite different from those observed in T cell ALL, as 20 of 23 patients retained at least one germline band of the T gamma gene. In contrast, all T cell ALL patients showed no retention of germline bands. These data indicate that rearrangement of the T gamma gene is not specific for T cell ALL. Further, the results also suggest that T gamma gene rearrangement precedes T beta gene rearrangement. The combined analysis of rearrangement patterns of IgH, T beta, and T gamma genes provides new criteria for defining the cellular origin of leukemic cells and for further delineation of leukemia cell heterogeneity. 相似文献
59.
CL Sanchez CS Biskup S Herpertz TJ Gaber CM Kuhn SH Hood FD Zepf 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(10)
The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research. 相似文献
60.
Melatonin suppresses NO-induced apoptosis via induction of Bcl-2 expression in PGT-beta immortalized pineal cells 总被引:2,自引:0,他引:2
Yoo YM Yim SV Kim SS Jang HY Lea HZ Hwang GC Kim JW Kim SA Lee HJ Kim CJ Chung JH Leem KH 《Journal of pineal research》2002,33(3):146-150
In the present study, we investigated whether melatonin would prevent nitric oxide (NO)-induced apoptotic death of PGT-beta immortalized pineal cells. To examine the protective effect of melatonin, cytotoxicity assay, DNA fragmentation analysis, caspase-3 activity assay, and Western blotting for caspase-3 and poly(ADP-ribose) polymerase (PARP) were performed. Treatment of cells with S-nitroso-N-acetylpenicillamine (SNAP), an NO donor, was shown to induce apoptotic cell death in a dose-dependent manner, and pretreatment with melatonin (0.1 mm) attenuated the occurrence of NO-induced apoptotic cell death. DNA fragmentation in response to NO was also arrested by melatonin. Caspase-3 activity induced by NO was decreased with melatonin treatment. Furthermore, the active fragments of caspase-3 and PARP were almost completely absent following exposure to melatonin. To elucidate the protective mechanisms of action of melatonin, Western blot analyses for Bcl-2 expression and cytochrome c release were carried out. Pretreatment with melatonin (0.1 mm) induced the expression of Bcl-2 and suppressed the release of cytochrome c into the cytosol, thereby arresting NO-induced apoptotic cell death. These results suggest that the antiapoptotic effect of melatonin is associated with induction of Bcl-2 expression in PGT-beta cells, which in turn blocks caspase-3 activation and inhibits cytochrome c release into the cytosol. 相似文献