A prototype of the forward tracking array consisting of three multiwire drift chambers（MWDC） for the external target experiment（CEE） at the Heavy Ion Research Facility at the Lanzhou-Cooling Storage Ring（HIRFL-CS...A prototype of the forward tracking array consisting of three multiwire drift chambers（MWDC） for the external target experiment（CEE） at the Heavy Ion Research Facility at the Lanzhou-Cooling Storage Ring（HIRFL-CSR） has been assembled and tested using cosmic rays. The signals from the anode wires are amplified and fed to a Flash-ADC to deliver the drift time and charge integration. The performances of the array prototype are investigated under various high voltages. For the tracking performances, after the space-time relation（STR）calibration and the detector displacement correction, the standard deviation of 223 μm of the residue is obtained.The performances of the forward MWDCs tracking array meets the requirements of CEE in design.展开更多
MicroRNAs （miRNAs） are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs （mRNAs）. Regulation is accomplis...MicroRNAs （miRNAs） are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs （mRNAs）. Regulation is accomplished when the 22-25 nucleotide miRNAs bind to complementary sequences in the 3＇-untranslated regions （UTR）. One barrier to miRNA research is to find target genes. Although computational target predictions have shed light on important aspects of microRNA target recognition, questions remain concerning the rates of false positives. In addition, we do not completely understand how microRNAs can recognize and regulate their targets. As such, experimental positive predictions and allow for an unbiased stu ap dy proaches are required, which can reflect in vivo processes, eliminating false of microRNA target recognition. In this review, we summarized experimental approaches that have been described for the identification and validation of mRNA targets associated with specific miRNAs.展开更多
To investigate the radioimmunotherapeutic efficacy, radio-immunoconjugate 131-I-3G9, 811-I-3H11 and 131-I-NMIgG (irre levant antibody) were i.p. injected into nude mice bearing human gastric cancer xenograftes. Each a...To investigate the radioimmunotherapeutic efficacy, radio-immunoconjugate 131-I-3G9, 811-I-3H11 and 131-I-NMIgG (irre levant antibody) were i.p. injected into nude mice bearing human gastric cancer xenograftes. Each animal received a single doses of 555MBq. Over 14 days the accumulative absorbed doses in tumors were 13.7 Gy for 131-I-3H11 and 12.17 Gy for 131-I-3G9. Both were significantly higher than that for 131-I-NMIgG (3.23 Gy). Thera peutic efficacy appeared most sharply from 2 to 3 weeks after injection. The inhibition ratio of tumor were 86% and 70% for 131-I-3H11 and 131-I-3G9 respectively. Histopathological evidance indicated that in tumor tissues radioactive damage was showed as karyopyknosis, karyorrhexis and necrosis or partial disappearance of tumor cells, while in the other tissues no radioactive damage was observed. WBC counts of all animals did not show significant difference before and after treatment, which indicated that the haemopoietic function of bone marrow was not affected.展开更多
Anti-hepatoma monoclonal antibodies HAb8,HAb18 IgG and HAb18 F（ab’）<sub>2</sub>were labelled with[<sup>131</sup>I]according to chloramine T method.The labelling rate andradioactivity were 51...Anti-hepatoma monoclonal antibodies HAb8,HAb18 IgG and HAb18 F（ab’）<sub>2</sub>were labelled with[<sup>131</sup>I]according to chloramine T method.The labelling rate andradioactivity were 51% and 9.58×10<sup>4</sup>Bq/mg,respectively.After administration of the[<sup>131</sup>I]-labelled conjugates through mouse tail vein,hepatoma xenografts were clearly im-aged,Localization index was 2.15,3.09,and 6.99 for HAb8,HAb18 IgG and HAb18F（ab’）<sub>2</sub>,respectively.A total of 16 hepatoma-bearing nude mice（中央人民政府-LTNM）were di-vided into 4 groups.When xenografts reached 0.3cm in diameter,the treatment was be-gun by injection of the[<sup>131</sup>I]-conjugates through mouse tail vein.After 2 weeks of treat-ment,obvious inhibitory or killing effects on the xenografts were found.The tu-mor-bearing mice were killed during the period from 14 to 21d after treatment.Xenografts as well as other organs were sampled and viewed under light microscope ac-cording to routine procedure.The vital organs,such as heart,liver,spleen,lung,kidneyand brain showed no pathological lesions.In hepatoma xenografts,some tumor cellmembranes were found,with obscure cytoplasmic structure and increased eosinophilia,representing necrotic alterations.展开更多
To seek an inexpensive supersonic target,characteristics of various targets are analyzed,its tactical and technical specifications are drafted,and a refitting scheme using big-caliber supersonic rockets is put forward...To seek an inexpensive supersonic target,characteristics of various targets are analyzed,its tactical and technical specifications are drafted,and a refitting scheme using big-caliber supersonic rockets is put forward. An optimization model to meet tactical and technical requirements is built,in which the speed and the trajectory angle at the end of active phase are used as the design variables and the horizontal flight distance of the target is used as the objective function. The simulated results show that the method is reasonable and feasible.展开更多
基金Supported by Natural Science Foundation of China(11079025,11375094,U1332207)Tsinghua University Initiative Scientific Research Program
文摘A prototype of the forward tracking array consisting of three multiwire drift chambers（MWDC） for the external target experiment（CEE） at the Heavy Ion Research Facility at the Lanzhou-Cooling Storage Ring（HIRFL-CSR） has been assembled and tested using cosmic rays. The signals from the anode wires are amplified and fed to a Flash-ADC to deliver the drift time and charge integration. The performances of the array prototype are investigated under various high voltages. For the tracking performances, after the space-time relation（STR）calibration and the detector displacement correction, the standard deviation of 223 μm of the residue is obtained.The performances of the forward MWDCs tracking array meets the requirements of CEE in design.
基金Supported by the National Natural Science Foundation of China (30570990, 30471059, 31171578)the "863" project (2008AA10Z153)+2 种基金the Key Research Plan of Heilongjiang Province (GA06B103-3)the Innovation Research Group of NEAU (CXT004)the Research Fund for the Doctoral Program of Higher Education of China (20102325120002)
文摘MicroRNAs （miRNAs） are a group of regulatory RNAs that regulate gene expression post-transcriptionally by the degradation or translational inhibition of their target messenger RNAs （mRNAs）. Regulation is accomplished when the 22-25 nucleotide miRNAs bind to complementary sequences in the 3＇-untranslated regions （UTR）. One barrier to miRNA research is to find target genes. Although computational target predictions have shed light on important aspects of microRNA target recognition, questions remain concerning the rates of false positives. In addition, we do not completely understand how microRNAs can recognize and regulate their targets. As such, experimental positive predictions and allow for an unbiased stu ap dy proaches are required, which can reflect in vivo processes, eliminating false of microRNA target recognition. In this review, we summarized experimental approaches that have been described for the identification and validation of mRNA targets associated with specific miRNAs.
文摘To investigate the radioimmunotherapeutic efficacy, radio-immunoconjugate 131-I-3G9, 811-I-3H11 and 131-I-NMIgG (irre levant antibody) were i.p. injected into nude mice bearing human gastric cancer xenograftes. Each animal received a single doses of 555MBq. Over 14 days the accumulative absorbed doses in tumors were 13.7 Gy for 131-I-3H11 and 12.17 Gy for 131-I-3G9. Both were significantly higher than that for 131-I-NMIgG (3.23 Gy). Thera peutic efficacy appeared most sharply from 2 to 3 weeks after injection. The inhibition ratio of tumor were 86% and 70% for 131-I-3H11 and 131-I-3G9 respectively. Histopathological evidance indicated that in tumor tissues radioactive damage was showed as karyopyknosis, karyorrhexis and necrosis or partial disappearance of tumor cells, while in the other tissues no radioactive damage was observed. WBC counts of all animals did not show significant difference before and after treatment, which indicated that the haemopoietic function of bone marrow was not affected.
文摘Anti-hepatoma monoclonal antibodies HAb8,HAb18 IgG and HAb18 F（ab’）<sub>2</sub>were labelled with[<sup>131</sup>I]according to chloramine T method.The labelling rate andradioactivity were 51% and 9.58×10<sup>4</sup>Bq/mg,respectively.After administration of the[<sup>131</sup>I]-labelled conjugates through mouse tail vein,hepatoma xenografts were clearly im-aged,Localization index was 2.15,3.09,and 6.99 for HAb8,HAb18 IgG and HAb18F（ab’）<sub>2</sub>,respectively.A total of 16 hepatoma-bearing nude mice（中央人民政府-LTNM）were di-vided into 4 groups.When xenografts reached 0.3cm in diameter,the treatment was be-gun by injection of the[<sup>131</sup>I]-conjugates through mouse tail vein.After 2 weeks of treat-ment,obvious inhibitory or killing effects on the xenografts were found.The tu-mor-bearing mice were killed during the period from 14 to 21d after treatment.Xenografts as well as other organs were sampled and viewed under light microscope ac-cording to routine procedure.The vital organs,such as heart,liver,spleen,lung,kidneyand brain showed no pathological lesions.In hepatoma xenografts,some tumor cellmembranes were found,with obscure cytoplasmic structure and increased eosinophilia,representing necrotic alterations.
文摘To seek an inexpensive supersonic target,characteristics of various targets are analyzed,its tactical and technical specifications are drafted,and a refitting scheme using big-caliber supersonic rockets is put forward. An optimization model to meet tactical and technical requirements is built,in which the speed and the trajectory angle at the end of active phase are used as the design variables and the horizontal flight distance of the target is used as the objective function. The simulated results show that the method is reasonable and feasible.
