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The control rod assembly is an important part of the fast reactor control system and safety protection system. The accurate solution of the fast reactor control rod worth is very important. The direct volume homogenization method is used in the calculation of the fast reactor few�group homogenization constants based on the PASC�5 code, which will lead to a serious overestimation of the control rod worth, and the heterogeneous effects of the control rod assembly must be corrected. Based on the idea of group constant correction, the applications of three methods including volume�flux weight, reaction rate ratio preservation, and reactivity preservation were studied in the correction of heterogeneous effects of fast reactor control rod assembly in the paper. Based on the two�dimensional characteristic line code, the calculation code named FRHP for the group constant correction was developed. Tested and verified by the China Experimental Fast Reactor case, the corrected control rod worth calculation results are in good agreement with the MCNP calculation reference results, indicating that the three methods can effectively correct the heterogeneous effects of the control rod assembly, among which the reactivity preservation method has the best correction effect.

Objective To know the influencing factors of dental caries in first permanent molars among children aged 10⁃12 years old in Guangzhou, and to give references for dental caries prevention. Methods The samples were selected by stratified random sampling method. Oral health examination and questionnaires were applied to all the 18 656 children who were 5 or 6⁃grade in 149 primary schools. Results The prevalence of dental caries in first perma⁃ nent molars was 18.19%. Girls accouted for 19.96%, which was significantly higher than that of boys (16.71%) (c2 = 32.817, P < 0.001). Multiple regression analyses were used to investigate the influencing factors of dental caries in first permanent molars. After controlling school cluster and other factors, household register, gender, pit and fissure sealant, consumption of sweets and chocolates, consumption of sweet milk were influencing factors of permanent teeth caries. And household register, gender, pit and fissure sealant, consumption of sweets and chocolates were associated with mean DMFT. Conclusion school oral health education should focus on the consumption of sugars and cares should be put into the differences between urban and rural area. In addition, strengthening publicity of the sealant retention proj⁃ ect,raising public awareness, and improving sealant retention quality are necessary to ensure the anti⁃caries effect.

Objective: To develop a reduction device for the arthroscopy-assisted treatment of tibial plateau fracture and explore its clinical efficacy., Methods: From May 2018 to September 2019, 21 patients with tibial plateau fracture were treated, including 17 males and 4 females. Their ages ranged from 18 to 55 years old with an average of (38.6±8.7) years old. There were 5 cases of Schatzker typeⅡand 16 cases of Schatzker type Ⅲ. The self-designed reductor combined with arthroscope was used for auxiliary reduction and fixation(minimally invasive percutaneous plate osteosynthesis). The efficacy was analyzed by observing the operation time, blood loss, fracture healing time and knee function(HSS and IKDC scoring criteria)., Results: All the 21 patients were followed up for 8 to 24 with an average of(14.0±3.1) months. The operative time ranged from 70 to 95 min with an average of(81.7±7.6)min, incision length ranged from 4 to 7 cm with an average of(5.3±0.9) cm, intraoperative blood loss ranged from 20 to 50 ml with an average of(35.3±5.2) ml, postoperative weight-bearing time ranged from 30 to 50 d with an average of(35.1±9.2) d, fracture healing time ranged from 65 to 90 d with an average of(75.0±4.4) d, and complications were 0 cases, respectively. The fracture was well healed and no screw plate fracture was observed. The knee function scores of HSS and IKDC 18 months after operation were significantly higher than those before operation( P <0.05)., Conclusion: The custom-made reduction tool for the arthroscopic management of tibial plateau fracture is reasonable in design and simple in operation. The specific reduction tool could effectively reduce the fracture, and shorten the fixation time with minimally invasive procedure.

Objective: To investigate the value of CD44 + mononuclear cells (MNC) and spleen stiffness measurement (SSM) in minimal residual disease (MRD) in acute myeloid leukemia (AML) and its prognosis., Methods: Flow cytometry was used to detected the proportion of CD44 + and CD24 + MNC in 44 AML patients after induction chemotherapy. The SSM was tested by FS. The value of MNC and SSM in MRD and its prognosis was explored., Results: The percentage of CD44 + MNC and SSM in MRD positive group were significantly higher than those in MRD negative group (P<0.05). In MRD positive group, there were positive correlation between CD44 + MNC, SSM and MRD level (r=0.998, r=0.939, P<0.05). The median EFS and OS in HCD44 + MNC and HSSM groups were significantly shorter than those in LCD44 + MNC and LSSM (P<0.05). CD24 + MNC showed no association with MRD and its prognosis., Conclusion: HCD44 + MNC and HSSM may be used to predict high level MRD and poor prognosis.

Objective: To detect the relationship between leukocytes derived microparticle (CD45 + MP) and minimal residual disease (MRD) and prognosis of acute myeloid leukemia (AML)., Methods: The expression of CD45 + MP, CD44 + MP and CD24 + MP in peripheral blood of 47 AML patients at the time after induction chemotherapy were detected by using flow cytometry, and the relationship between MP, MRD and prognosis were analyzed., Results: The percentages of CD45 + MP, CD44 + MP and CD24 + MP in MRD positive group were significantly higher than those in MRD negative group. In MRD positive group, there were positive correlation between CD45 + MP, CD44 + MP, CD24 + MP and MRD level. The AUC of CD45 + MP, CD44 + MP, CD24 + MP in predicting positive MRD was 0.949, 0.782, and 0.817, respectively. The EFS and OS in HCD45 + MP, HCD44 + MP and HCD24 + MP groups were significantly shorter than low level group., Conclusion: High level of CD45 + MP, CD44 + MP, CD24 + MP can be used to predict high level MRD and poor prognosis.

Objective: To investigate the antitumor effect of lycorine on renal cell carcinoma ACHN cells and explore the possible mechanism., Methods: We used flow cytometry to examine the effect of lycorine on ACHN cell cycle and apoptosis. The cell proliferation, migration and invasion were assessed with MTS assay, wound healing assay, and Transwell assay, respectively. Colony forming assay was performed, and the mRNA and protein levels of Bax, Bcl-2, survivin, caspase-3, cyclin D1 and CDK4 were measured with qRT-PCR and Western blotting., Results: Lycorine obviously inhibited the proliferation of ACHN cells with an IC(50) of 24.34 µmol/L. Lycorine also induced apoptosis of ACHN cells, caused cell cycle arrest at G(0)/G(1) phase, and suppressed the colony forming ability of the cells in a dose-dependent manner. The migration and invasion of ACHN cells were significantly inhibited by 5 µmol/L lycorine. Lycorine up-regulated the mRNA levels of CDK4, Bax, caspase-3 while down-regulated the levels of survivin, Bcl-2 and Cyclin D1; the protein levels of CDK4 and Bax were increased and cyclin D1, Bcl-2 and surviving expressions were decreased, but caspase-3 expression showed no significant changes following the treatment., Conclusion: Lycorine has obvious antitumor effect against ACHN cells, suggesting its value as a new therapeutic agent for renal cell carcinoma.

We isolated and identified the genotypes and molecular characteristics of the imported B3 measles virus (MeV) in the Chinese mainland. The Vero/SLAM cell line was used to isolate the viruses. Reverse transcription-polymerase chain reaction was undertaken to amplify the 450 nucleotide acids of the 3-terminal of the nucleoprotein gene. A phylogenetic tree was constructed and similarities in homology assessed. Results suggested that the Shanghai isolates MVi/Shanghai. CHN/38. 13/02 [B3] and MVi/Shanghai. CHN/40. 13/02[B3] were clustered within the same genotype group as the World Health Organization (WHO) B3 genotype reference strain. The number of differences in nucleotide acids between the two Shanghai isolates was one. The homology of nucleotide acids between the Shanghai isolates and the WHO B3 genotype reference strain (MVi/Ibadan. NGA/0.97/1/B3) was 98%. Comparative results from the Measles Nucleotide Surveillance system suggested that the sequences of Shanghai isolates and the 2013 vi- ruses from Australia, Japan, Korea, Hong Kong China, Philippines and Iran were identical. This is the first time that the B3 genotype of MeV in the Chinese mainland has been isolated since 1993. These data can be used to create a "baseline" of genetic information for measles viruses in China, and help to trace the transmission of measles viruses in China and the rest of the world.

This study analyzed the genetic characterization on first imported measles virus of genotype D8 in Chinese mainland. Serums were collected from the suspicious MV patients to detect IgM antibody in ELISA. Throat swabs were cultured in Vero/SLAM cell line to get measles virus isolates. Part of the nucleotide sequence of the 3' terminus of nucleoprotein (N) gene of these isolates were amplified by RT-PCR, and the amplicons were directly sequenced. The phylogenetic analysis was based on the nucleotide sequence about 456 base pairs of the 3' terminus of nucleoprotein (N) gene. Results showed that it reported 1 105 suspicious measles cases in shanghai, 2012, including 590 confirmed cases and 2 clinical case. The reported morbidity was 2.52 per one hundred thousand. 247 measles viruses were isolated from 984 throat swabs specimen. Most of them belonged to sub-genotype H1a except Shanghai12-239 was genotype D8. The homology of nucleotide and amino acid sequences were 97.8% and 98.6% respectively between Shanghai12-239 and WHO reference strain (Manchester. UNK30.94(D8)AF280803). Those were 89.6%-94.5% and 88.7%-95.3% between Shanghai12-239 and WHO reference strains of other genotypes.

Objective: To evaluate the reliability of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) expression in breast cancer by immunohistochemistry and discuss their influencing factors., Methods: The pretreatment biopsy specimens were collected from 148 patients (from Beijing Cancer Hospital between 2004 to 2010) with invasive breast cancer. After reslicing and staining (ER:SP1, PR: 1E2, HER-2: 4B5), the status of ER, PR and HER-2 was analyzed by a pathological expert with automated imaging system Ariol MB-8. And their results were compared with the original reports., Results: The concordance rates between original reports and automated image system were ER:76.35%, PR:49.32%, HER-2:63.51% while Kappa values 0.12 (P = 0.020) , 0.18 (P = 0.002) and 0.08 (P = 0.200) respectively. And the concordance rates between expert reports and automated image system were ER:93.92%, PR:81.08% and HER-2:76.35% while Kappa values 0.77 (P < 0.001) , 0.67 (P < 0.001) and 0.32 (P < 0.001) respectively., Conclusion: For the expressions of ER, PR and HER-2, the disaccording results of original reports and automated image system may be mainly due to the differences of antibodies, staining methods and interpretations.

Objective: To assess the prognostic value of lymph node ratio (LNR) in patients with stage III rectal cancer after curative resection., Methods: A retrospective review of the clinicopathological data was performed in 161 patients with stage III rectal cancer who received curative surgical excision in our hospital from June 2005 to June 2010. The variables including LNR, age, gender, T stage, N stage, total number of dissected lymph nodes, number of metastatic lymph nodes, and positive rate of lymph node metastasis were studied through univariate and multivariate analyses, and the survival analysis was performed using Kaplan-Meier method and Log rank test., Results: Multivariate analysis revealed that LNR, but not number of positive nodes or number of harvested lymph nodes, had independent prognostic value for overall survival and disease-free survival for patients with stage III rectal cancer. The overall survival in the LNR < 0.43 and LNR ≥ 0.43 groups was 75.8% and 41.3%, respectively (P < 0.01), while the disease-free survival was 68.8% and 40.3%, respectively (P = 0.001)., Conclusions: The LNR is an independent prognostic factor for survival of patients with stage III rectal cancer, and is more efficient than the number of positive nodes and total number of dissected lymph nodes in the survival prediction.

Throat swabs collected from patients whose serum was measles IgM negative and rubella IgM positive during 2001-2011 were used to conduct cell culture for rubella virus. After identification of cell culture with RT-PCR, nucleotide of gene E1 of rubella virus was amplified and sequenced, followed by molecular epidemiological analysis. A total of 31 rubella viruses were isolated from 60 throat swabs. Compared 27 isolates with the WHO reference strains of all genotypes, phylogenetic tree was constructed based on the amplified 739 nucleotide fragment. These isolates belonged to two different genotypes respectively. Isolates 11009, 11052 and 11106 in 2011 belonged to genotype 2B, and others belonged to genotype 1E. Most of mutations were nonsense mutation, and sequence of amino acid was highly conserved. Amino acid sequence of most isolates of genotype 1E was identical, which suggested rubella viruses from same transmission chain might be transmitted continually since 2001. Rubella virus genotype 2B was found to be popular for the first time in Shanghai in 2011. The nucleotide sequences of these genotype 2B isolates showed 99% identity compared with that of isolates recently from Vietnam, Japan and Argentina. The resources of these strains were not confirmed due to the absence of rubella virus surveillance before.

Objective: To make serological analysis and identify the etiology of an outbreak of chickenpox in Zhabei District of Shanghai in 2007., Methods: IgM and IgG of the paired serums were detected by ELISA. The collected herpes were inoculated into MRC-5 cells to get VZV isolations and identify them by VZV standard serums. A 268bp fragment was amplified by specific PCR primers., Results: Among the five paired serums, two of the acute phase serums were VZV IgM positive, one was VZV IgG positive, and two were equivocal for anti-VZV IgG. All of the convalescent serums were VZV IgG positive, and four of them were 4 times higher in antibody titer than those of acute phase serums. Viruses were isolated from all of the 5 herpes, and then identified by VZV standard serum. The electrophoresis result of PCR products showed the single specific strap., Conclusions: This outbreak was caused by VZV virus. 47.4% of the patients were inoculated in postnatal or domestic VZV vaccines in China 3 years after delivery. The effectiveness of VZV vaccine has been certified. It is necessary to consider the immunization strategy of VZV vaccine.