AIM： To describe and discuss echo-enhanced sonography in the differential diagnosis of cystic pancreatic lesions. METHODS： The pulse inversion technique （with intravenous injection of 2.4 mL SonoVue） or the power-...AIM： To describe and discuss echo-enhanced sonography in the differential diagnosis of cystic pancreatic lesions. METHODS： The pulse inversion technique （with intravenous injection of 2.4 mL SonoVue） or the power-Doppler mode under the conditions of the 2^nd harmonic imaging （with intravenous injection of 4 g Levovist） was used for echo-enhanced sonography. RESULTS： Cystadenomas frequently showed many vessels along fibrotic strands. On the other hand, cystadenocarcinomas were poorly and chaotically vascularized. ＂Young pseudocysts＂ were frequently found to have a highly vascularised wall. However, the wall of the ＂old pseudocysts＂ was poorly vascularized. Data from prospective studies demonstrated that based on these imaging criteria the sensitivities and specificities of echoenhanced sonography in the differentiation of cystic pancreatic masses were 〉 90%. CONCLUSION： Cystic pancreatic masses have a different vascularization pattern at echo-enhanced sonography. These characteristics are useful for their differential diagnosis, but histology is still the gold standard.展开更多
In this paper, an online optimal distributed learning algorithm is proposed to solve leader-synchronization problem of nonlinear multi-agent differential graphical games. Each player approximates its optimal control p...In this paper, an online optimal distributed learning algorithm is proposed to solve leader-synchronization problem of nonlinear multi-agent differential graphical games. Each player approximates its optimal control policy using a single-network approximate dynamic programming(ADP) where only one critic neural network(NN) is employed instead of typical actorcritic structure composed of two NNs. The proposed distributed weight tuning laws for critic NNs guarantee stability in the sense of uniform ultimate boundedness(UUB) and convergence of control policies to the Nash equilibrium. In this paper, by introducing novel distributed local operators in weight tuning laws, there is no more requirement for initial stabilizing control policies. Furthermore, the overall closed-loop system stability is guaranteed by Lyapunov stability analysis. Finally, Simulation results show the effectiveness of the proposed algorithm.展开更多
AIM:To isolate and analyze the DNA sequences which are methylated differentially between gastric cancer and normal gastric mucosa. METHODS: The differentially methylated DNA sequences between gastric cancer and normal...AIM:To isolate and analyze the DNA sequences which are methylated differentially between gastric cancer and normal gastric mucosa. METHODS: The differentially methylated DNA sequences between gastric cancer and normal gastric mucosa were isolated by methylation-sensitive representational difference analysis (MS-RDA). Similarities between the separated fragments and the human genomic DNA were analyzed with Basic Local Alignment Search Tool (BLAST). RESULTS: Three differentially methylated DNA sequences were obtained, two of which have been accepted by GenBank. The accession numbers are AY887106 and AY887107. AY887107 was highly similar to the 11th exon of LOC440683 (98%), 3' end of LOC440887 (99%), and promoter and exon regions of DRD5 (94%). AY887106 was consistent (98%) with a CpG island in ribosomal RNA isolated from colorectal cancer by Minoru Toyota in 1999. CONCLUSION: The methylation degree is different between gastric cancer and normal gastric mucosa. The differentially methylated DNA sequences can be isolated effectively by MS-RDA.展开更多
文摘AIM： To describe and discuss echo-enhanced sonography in the differential diagnosis of cystic pancreatic lesions. METHODS： The pulse inversion technique （with intravenous injection of 2.4 mL SonoVue） or the power-Doppler mode under the conditions of the 2^nd harmonic imaging （with intravenous injection of 4 g Levovist） was used for echo-enhanced sonography. RESULTS： Cystadenomas frequently showed many vessels along fibrotic strands. On the other hand, cystadenocarcinomas were poorly and chaotically vascularized. ＂Young pseudocysts＂ were frequently found to have a highly vascularised wall. However, the wall of the ＂old pseudocysts＂ was poorly vascularized. Data from prospective studies demonstrated that based on these imaging criteria the sensitivities and specificities of echoenhanced sonography in the differentiation of cystic pancreatic masses were 〉 90%. CONCLUSION： Cystic pancreatic masses have a different vascularization pattern at echo-enhanced sonography. These characteristics are useful for their differential diagnosis, but histology is still the gold standard.
文摘In this paper, an online optimal distributed learning algorithm is proposed to solve leader-synchronization problem of nonlinear multi-agent differential graphical games. Each player approximates its optimal control policy using a single-network approximate dynamic programming(ADP) where only one critic neural network(NN) is employed instead of typical actorcritic structure composed of two NNs. The proposed distributed weight tuning laws for critic NNs guarantee stability in the sense of uniform ultimate boundedness(UUB) and convergence of control policies to the Nash equilibrium. In this paper, by introducing novel distributed local operators in weight tuning laws, there is no more requirement for initial stabilizing control policies. Furthermore, the overall closed-loop system stability is guaranteed by Lyapunov stability analysis. Finally, Simulation results show the effectiveness of the proposed algorithm.
基金The Key Project Fund of the Science and Technology Program of Hunan Province, No. 04SK1004the Scientific Research Fund of Educational Department, Hunan Province, No. 99C195
文摘AIM:To isolate and analyze the DNA sequences which are methylated differentially between gastric cancer and normal gastric mucosa. METHODS: The differentially methylated DNA sequences between gastric cancer and normal gastric mucosa were isolated by methylation-sensitive representational difference analysis (MS-RDA). Similarities between the separated fragments and the human genomic DNA were analyzed with Basic Local Alignment Search Tool (BLAST). RESULTS: Three differentially methylated DNA sequences were obtained, two of which have been accepted by GenBank. The accession numbers are AY887106 and AY887107. AY887107 was highly similar to the 11th exon of LOC440683 (98%), 3' end of LOC440887 (99%), and promoter and exon regions of DRD5 (94%). AY887106 was consistent (98%) with a CpG island in ribosomal RNA isolated from colorectal cancer by Minoru Toyota in 1999. CONCLUSION: The methylation degree is different between gastric cancer and normal gastric mucosa. The differentially methylated DNA sequences can be isolated effectively by MS-RDA.
