The causes of "Plateau Phenomenon"in College English learning are analyzed on the basis of the investigation and the study of the Learning Curve.Some solutions to cope with the stagnation are also suggested.It's worth attention that Learning Strategy can be a vital factor to overcome the"Plateau Phenomenon."

Objective To elucidate the role of human bone marrow stromal cells (hBMSC) in combination with exogenous cytokines such as stem cell factor(SCF) and FLT 3 ligand (FL) in supporting the in vitro expansion of CD 34 + cells purified from cord blood.Methods CD 34 + cells were isolated from umbilical cord blood by using a high gradient magnetic cell sorting system(MACS),expanded in combination with SCF,IL3 (interleukin 3),IL 6 (interleukin 6),FL,EPO (erythropoietin),and were planted onto the pre established irradiated (20Gy) stroma layer(hBMSC plus combinations of cytokines) respectively.On day 10,total cells were counted, and hematopoietic progenitor cells were assessed by semisolid culture assay,CD 34 + cells were quantitated by FACS.Results After separation by MACS,the frequency of CD 34 + cells was 92%?0.04%.On day 2,almost all the inoculated cells adhered to the stroma layer,with only a small number in the supernatant.Then,cells in the supernatant increased gradually, but the percentage of CD 34 + cells decreased.Compared with control, expansion fold of CD 34 + cells, CFU GM, BFU E were significantly higher in hBMSC group (P 0.5).Conclusion ① CD 34 + cells from cord blood formed foci adherent to the monolayer and colony forming cells remained in the culture of 10days,indicating that hBMSC can support hematopoiesis in vitro;②using human bone marrow stromal cells in cooperation with exogenous cytokines may be a feasible way to expand hematopoietic stem/progenitor cells.

· AIM: To study the expression of basic fibroblast growth factor (bFGF) receptor protein in human lens epithelial cells (HLECs). METHODS: Immunohistochemistry was used to detect the level of bFGF receptor protein and image analysis was adopted to perform the relative quantitative analysis on it. · RESULTS: There was bFGF receptor protein in HLECs accordingl to both qualitative and quantitative analysis. · CONCLUSION: bFGF receptor protein exists in HLECs and it is the material foundation for bFGF to improve the proliferation of HLECs.

Animals ; Heparin ; pharmacology ; Humans ; Ligands ; Lymphatic Metastasis ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Neoplasms ; metabolism ; pathology ; Oligosaccharides ; metabolism ; Selectins ; metabolism ; physiology ; Signal Transduction

Objective:To analyze the clinical effect and safety of Lingdan tablets and Wuling capsules in the treatment of alopecia areate. Methods:Totally 84 patients with alopecia areate were divided into the observation group and the control group with 42 ones in each. Minoxidil tincture was used for external in the two groups. The control group were treated with 0. 9 g Lindan tablets, tid, for 4 months and the treatment group was additionally treated with 0. 99 g Wuling capsules,po,tid, for 4 months. The changes in the area and position of trichomadesis, light pull test, the tissue growth score and Pittsburgh Sleep Quality Index ( PSQI) score were compared before and after the treatment. Results:The efficacy of the observation group was better than that of the control group(P<0. 05). Af-ter the treatment, the evaluated indices in the two groups were lower than those before the treatment(P<0. 01), and the reduction of the observation group was more significant than that of the control group(P<0. 01) . There was no notable adverse reaction appeared in the observation group. Conclusion:Lingdan tablets and Wuling capsules can improve sleeping quality, promote the growth of halr and enhance the curative effect.

Objective To compare the biomechanical properties between the two-level fixation by im- plantation of pedicle-screws into the adjacent upper and lower vertebrae of the fractured vertebra and the three-level fixation by implantation of pedicle screws into the fractured vertebra and its adjacent upper and lower vertebrae in the treatment of thoracolumbar burst fractures.Methods Eight fresh frozen calf spines were used in this study.Each specimen was tested in four models:intact model as the control,L1 burst fracture model,two-level fixation model, and three-level fixation model.The L1 burst fracture model was created on a biaxial material testing machine (MTS858 Bionix test system,America).During the experiment,the flexion,extension,bilateral bending and axial rotation loadings were applied to the specimens and the range of motion(ROM)was measured with a three-dimensional laser analysis apparatus and the stiffness was calculated subsequently.One-way statistical analysis was used.Results The ROMs under six different loadings in the fracture model became larger obviously(P＜0.05)and the stiffness decreased(P＜0.05).The ROMs in both fixation models were smaller than those in the other models(P＜0.01)and the stiffness increased distinctly(P＜0.05).There were no significant differences in ROMs and stiffness between the two-level fixation and three-level fixation models(P＞0.05).Conclusion Two-level fixation provides similar biomechanical stability as three-level fixation does in the reconstruction of unstable thoracolumbar fractures.

Abstract: Objective　To analyze the genotype of carbapenemase resistance genes and their genetic homology in multidrug-resistant Acinetobacter baumannii, and to provide a theoretical basis for guiding the rational use of antibiotics and controlling the prevalence of nosocomial infections. Methods A total of 83 multidrug-resistant Acinetobacter baumannii isolated from patients in the intensive care unit (ICU) and environmental specimens in the Sixth People's Hospital of Nantong from July 2020 to December 2021 were collected. The bacteria were identified and subjected to drug sensitivity tests using the BioMérieux DL96-Ⅱ automatic bacterial identification susceptibility system. The carbapenemase-related drug resistance gene types were detected using the polymerase chain reaction (PCR) method, and clones were analyzed by pulsed field gel electrophoresis (PFGE). Results The types of 83 ICU Acinetobacter baumannii specimens include sputum (43 strains), broncholavage fluid (20 strains), and surfaces of objects such as ventilators (20 strains). The resistance rates of all strains to imipenem, tetracycline, gentamicin, amikacin and ciprofloxacin were 100%, 32.5%, 38.6%, 41.0% and 77.1% respecitively, while the resistance rates to others such as ticarcillin and clavulanate were greater than 95%. All strains carried were detected to carry OXA-23 and OXA-51 genes, while OXA-24, OXA-58, IMP-1, VIM, IMP-4, SIM and NDM-1 resistance genes were all negative. PFGE homology analysis confirmed that 83 strains of Acinetobacter baumannii, with counts of 12, 18, 12, 13, 10, 6, 7, 5 respectively, mainly A, B, C, D, E clones, the rest were sporadic clones. Conclusions The carbapenem resistant Acinetobacter baumannii isolated from our ICU are widely drug-resistant to commonly used antimicrobial drugs, with B clone strain being the major prevalent strain. Carrying OXA-23 and OXA-51 genes may be an important reason for the resistance of Acinetobacter baumannii to carbapenem antibiotics in our ICU. Rational use of antimicrobial drugs, enhanced monitoring of bacterial resistance, and effective control of the generation and further spread of drug-resistant strains should be emphasized.

Child, Preschool ; Dwarfism ; congenital ; diagnosis ; Humans ; Male ; Osteochondrodysplasias ; congenital

Objective To explore the value of strain rate imaging (SRI) technology in the diagnosis of hypertension patient with re-gional left ventricular early diastolic dysfunction. Methods 50 essential hypertension patients were divided into hypertension Group Ⅰ and Group Ⅱ, including 31 patients with normal left ventricular and 19 patients with left ventricular hypertrophy. 25 healthy people were used as the control group. SRI was done in the six different basal myocardial segments and the parameters of SRI were compared with that of Doppler tissue imaging (DTI) and pulse Doppler (PW). Results In the hypertension group, SRe of the six different basal myocardial segments was lower than that in the control group (P<0.05), but (SRa) of hypertension group was higher (P<0.05). SRe was negatively correlated with the patients'illness development (r=-0.89, P<0.05), but SRa was positively correlated (r=0.97, P<0.05). And the SRe/SRa<1 detection rate of Group Ⅱ was higher than that in Group Ⅰ, and the ratio in the control group was lowest(P<0.05). Total detection rate of SRI (88%) was higher than Em/Am <1 of DTI (79.67%) and E/A < 1 of PW(60%), and these changes were more obvious in Group Ⅰ. SRI was higher than DTT and PW (P<0.05). Conclusion Compared with traditional technology and methods, SRI could pro-vide more accurate diagnoses to hypertension patient with regional left ventricular early diastolic dysfunction.

Objective To make sure whether Bcrp1 is the marker of cervical cancer stem-like cells or not by studying the characterization of Bcrp1+ HeLa cells.Methods Immunofluorescence stained flow cytometry and electron microacope were used to sort and observe uhrastructures of Bctp1+ and Bcrp1- HeLa cells.Flow cytometry wag used to identify the cycle and the rate of apoptosis with annexin V in two group cells.The expression of proliferating cell nuclear antigen (PCNA)and caspase-3 were tested using western blot methed.Results (1)There were 7.1% Bcrp1+ cells and 92.9% Bcrol- cells in HeLa cells.Bcrp1+ HeLa cells were large in size of nuclear and nucleoli are clear.and there were rich of cytomicrosome and rough endoplasmic reticulum.After sorted and cultured for 24,48,72 hours,the adhesion in Bcrp1+ cells were 72.8%,81.1%,80.4%,respectively.While,they were 3.3%,18.7%,12.6%at each time for Bcrpl- cells(all P<0. 05 ). (2) There are more S phase cells in Bcrp1+ cells than that in Bcrp1- cells (54. 1% vs 21.1%, P <0. 05) ,while the percentage of G0/G1 and G2/M in Bcrp1 - cells were highter than those in Bcrp1 + cells (53.0% vs 44. 4% ,25.9% vs 1.5% ; all P <0. 05 ). The rate of apoptosis in Bcrp1+ cells was lower than that in Bcrp1 - cells (0. 2% vs 5.3%, P < 0. 05 ). ( 3 ) The expression of PCNA in Bcrp1 + cells was higher than that in Bcrp1- cells (3140 vs 2255, P< 0. 05 ), while the expression of caspase-3 of Bcrpl + cells was lower than that in Bcrp1 - cells ( 1970 vs 3551, P < 0. 05 ). Conclusion There are more vigor and ability of proliferation and lower rate of apeptosis in Bcrp1 + HeLa cells than those in Bcrp1 - cells ,which may be some characters of cervical cancer stem cells.