Academic English abstract is an important means of achieving international academic exchange.This article introduces writing content and writing skills for medical academic English abstract.

Objective:To construct the prokaryotic expression vector pET28a(+)-comE, to get the highest expression of comE in E. coli BL21(DE3), and to obtain the purified ComE fusion protein. Methods: ComE gene was amplified by PCR with specific primers from genome of Streptococcus mutans UA159. After digested by two restriction endonucleases BamH Ⅰand Xho Ⅰ, the gene segment was inserted into vector pET28a(+). Then the recombinant vector was transformed into E. coli BL21(DE3). The protein expression was induced by IPTG and the result was confirmed by Western blot. The solubility of the fusion protein was examined by 12% SDS-PAGE, and the expression conditions were optimized. Finally the fusion protein was purified by a two-step purification procedure utilizing Ni2+ chelating column and S75 size exclusion column. Results: The recombinant plasmid was confirmed by PCR, restriction endonucleases digestion and sequence analysis, which showed that the inserted segment was identical to comE gene reported by GenBank without nucleotide mutation. The fusion protein which was confirmed by Western blot can be expressed in E. coli BL21(DE3) and existed both in supernatant and precipitation. The maximum expression product amount was obtained when the A600 value of E. coli BL21(DE3) was 0.4, IPTG concentration was 0.10 mmol/L and induction time was 4 h. Conclusion: The recombinant plasmid is constructed and the ComE fusion protein is purified by the optimum conditions.

Objective To investigate the relationship between the expression of estrogen receptor (ER),progesterone receptor(PR)and epidermal growth factor receptor(EGFR)in uterine leiomyoma and the recurrence after myomectomy.Methods Eighty cases underwent myomectomy were enrolled in this study.ER,PR and EGFR expression in uterine leiomyoma tissue and normal myometrium tissue were examined by immunohistochemical technique.All the patients were followed up regularly after myomectomy.Results The positive expression rate of ER,PR and EGFR in uterine leiomyoma tissue were significantly higher than those in normal myometrium tissue[88.8％(71/80)vs.48.8％(39/80),92.5％(74/80)vs.30.0％ (24/80),86.2％(69/80)vs.57.5％(46/80),P ＜ 0.05].The recurrence rates in ER,PR and EGFR positive expression patients were significantly higher than those in negative expression patients[42.3％(30/71)vs.22.2％(2/9),41.9％(31/74)vs.16.7％(1/6),42.0％(29/69)vs.27.3％(3/11),P ＜ 0.05].The recurrence times in ER,PR and EGFR positive expression patients were significantly shorter than those in negative expression patients(P ＜0.05).The expression of EGFR had positive correlation with ER and PR(r =0.837,0.702,P ＜ 0.05).Conclusions The recurrence of uterine leiomyoma may have correlation with high expression of ER,PR and EGFR in uterine leiomyoma.

BACKGROUND: Basic fibroblast growth factor (bFGF) can promote mitosis and chemotaxis of periodontal ligament fibroblasts (PDLCs), and help the generation of extracellular matrix and new blood capillaries. But it is easy to degrade,has short half-life, and metabolizes rapidly.OBJECTIVE: To evaluate the influence of bFGF/chitosan/polylactic acid scaffolds on PDLCs growth and proliferation.METHODS: Polylactic acid/chitosan composite scaffolds in different proportions (4:1, 3:2, 1:1, 2:3, 1:4) were prepared through freeze-drying method, to study their microstructure, porosity and mechanical strength and then choose the optimal ratio of chitosan/polylactic acid scaffold that was used to prepare the composite scaffolds which contained different concentrations (0, 0.1, 1, 10, 100 μg/L) of bFGF. (1) Cytotoxicity test: PDLCs were cultured with leaching liquid of polylactic acid/chitosan scaffolds which contained different concentrations (0, 0.1, 1, 10, 100 μg/L) of bFGF and DMEM culture medium respectively. The effects on cell proliferation were tested by MTT after 24, 48, 72 hours. Cell cycles were tested using flow cytometry at 5 days of culture. (2) Cytocompatibility test: PDLCs were co-cultured with the polylactic acid/chitosan scaffolds which contained different concentrations (0, 0.1, 1, 10, 100 μg/L) of bFGF. The number of PDLCs was counted at 1, 3, 5 and 7 days. The growing status of PDLCs on the scaffolds was observed by scanning electron microscope at 3 days of culture.RESULTS AND CONCLUSION: (1) The best mass ratio of polylactic acid and chitosan was 2:3 by test of porosity and mechanical strength. (2) The absorbance value of each group was increased over time. The absorbance values of 0.1, 1, 10, 100 μg/L bFGF groups were higher than that of the control group (0 μg/L bGFG), and the A value of 10 μg/L group was highest in all groups at 48 and 72 hours after co-culture (P < 0.05). (3) Cell percentages at G0/G1 phase of 0.1, 1, 10,100 μg/L bFGF groups were higher than that of the control group, and the percentage of 10 μg/L group was lowest in all groups (P < 0.05). Cell percentage at S phase and G2/M+S of 0.1, 1, 10, 100 μg/L bFGF groups were higher than that of the control group, and the percentage of 10 μg/L group was highest in all groups (P < 0.05). (4) The number of cells in each group was increased with time. The cell number in the 10 μg/L was most in all groups at 3 and 5 days of co-culture (P < 0.05). Observation of scanning electron microscopy showed that PDLCs adhered and grew well on the 10 μg/L bFGF/polylactic acid/chitosan composite scaffold when co-cultured for 3 days. Overall, these findings indicate that the bFGF/polylactic acid/chitosan composite scaffold contributes to PDLCs proliferation.

BACKGROUND:Application of mechanical valve and bioprosthetic valve replacement is an effective means for the treatment of end-stage valve disease. However, their clinical application is constrained by multiple factors. Tissue-engineered heart valves with biological activity hold the potential to overcome the defect of the mechanical valves and bioprosthetic valves. Choosing appropriate cells for cellseeding is a significant aspect for the research of tissue-engineered heart valves. A growing number of somatic cells and stem cells have been used for construction of tissue-engineered heart valves, however, not yet achieve the desired result.
OBJECTIVE:To review the studies on seed cells for tissue-engineered heart valves and the cellseeding methods in vitro on the basis of the cellular components of heart valves.
METHODS:First author searched PubMed and Wanfang database with computer for related articles published from January 2000 to December 2012. The keywords were“tissue engineering, heart valves, cel”. Preferred articles concerned seed cells of tissue-engineered heart valves with the relevance and authority. A total of 39 articles published in the prestigious journals were reviewed.
RESULTS AND CONCLUSION:Endothelial cells and interstitial cells were mainly valvular cellular components. In the early stage, endothelial cells and fibroblasts were used to construct tissue-engineered heart valves. With deep stem cellresearch, the application of pulsatile bioreactor cultivation mesenchymal stem cells holds a great potential to produce tissue-engineered heart valves.

Objective To compare shikani optical stylet and Mc coy laryngoscope on elder patients with intratracheal intubation anesthesia.Methods 112 cases of elder patients with intratracheal intubation anesthesia were enrolled as study objects, all patients were divided into shikani optical stylet group (52 cases), Mc coy laryngoscope group (60 cases) according to different intubation way. Then detect the hemodynamic parameters, stress-related indicators, EEG relevant indicators of the two groups.Results One time success rate and total success rate in Shikani visual laryngoscope group was higher than Mc Coy visual laryngoscope group, while many times intubation rate was lower (P < 0.05); T1, T2 MAP, HR levels were lower in Shikani optical stylet group than Mc Coy laryngoscope group patients (P < 0.05); Plasma levels of epinephrine, norepinephrine, and glucose on T1, T2 in Shikani optical stylet group was lower than that in Mc Coy laryngoscope group (P < 0.05); T1, T2 BIS, ECoG grading, αβ% values in Shikani optical stylet group was lower than that in Mc coy laryngoscope group (P < 0.05).Conclusions Elderly patients with intratracheal intubation anesthesia received shikani optical stylet can enhance the success rate of intubation and effectively stabilize patients circulatory system, reduce excessive physical stress caused by various system dysfunction, which shows positive significance.

Objective To observe the efficacy and safety of the etomidate target controlled in-fusion (TCI)in the total thoracoscopic mitral valve replacement surgery.Methods One hundred and ten patients,aged 29-55 years,48 males and 62 females with ASA grade Ⅱ or Ⅲ rheumatic mitral valve disease planned to be corrected with total thoracoscopic mitral valve replacement surgery were randomly divided into group E and group P,55 cases in each group.In group E,etomidate-sufentanil target controlled infusion was used for induction (the initiate plasma concentration of etomidate was 0.2 ng/ml and increased 0.1 ng/ml per minute according to the bispectral index and the effect-site concentration of sufentanil was maintained at 1.0 ng/ml)and maintenance.In group P,using propo-fol-sufentanil target controlled infusion for induction (the initiate plasma concentration of propofol was 1.0 ng/ml and increased 0.3 ng/ml per minute according to the bispectral index and the effect-site concentration of sufentanil was maintained at 1.0 ng/ml)and maintenance.We documented the incidence of hypotension during the induction phase, recorded the basic clinical parameters of patients,the dosage of vasopressors during induction and sufentanil during anesthesia,time of eyelash reflex absence,operation time,CPB time,clamping time,APACHE Ⅱ score when enter CCU,pos-itive inotropic score 24 h postoperatively,wakening time,mechanical ventilation time,CCU stay,in-hospital stay,blood glucose and lactic acid preoperatively,2,6,24 h postoperatively,cortisol,aldo-sterone and adrenocorticotropin preoperatively and 24 h postoperatively and postoperative complications in both groups.Results The incidence of hypotension during induction in group E was much lower than that in group P (P<0.05).The dosage of norepinephrine during the induction in group E were much less than group P (P <0.05).The wakening time,mechanical ventilation time,CCU stay and in-hospital stay in group E were significantly shorter than group P (P <0.05).The blood glucose and lactic acid at postoperative 2,6,24 h were much higher than the preoperative value within each group (P <0.05).They reached the maxim at 6 h postoperatively and began to decline at 24 h postoperatively. Blood glucose and lactic acid at all the time points between two groups were similar.Cortisol at 24 h postoperatively was much higher than the preoperative value in group P (P <0.05).The dosage of cortisol and aldosterone 24 h postoperatively in group E were much less than that in group P (P <0.05).The incidence of postoperative lung infection in hospital in group E was remarkably lower than that in group P (P <0.05).Conclusion Etomidate target controlled infusion can maintain stable he-modynamics during the induction period, shorten postoperative recovery time and reduce postoperative lung infection obviously,which can be safely used in total thoracoscopic mitral valve re-placement surgery.

ObjectiveTo determine the effect of total mesorectal excision with double anastomosis instruments(DAIs) in lower rectal carcinoma. MethodsFrom 1995 to 1998,57 cases of middle and lower segement rectal carcinoma were treated by total mesorectal excision with DAIs, and were followed for 3 years. Results No operative death and no anastomotic leakage were noted. Two patients suffered from anastomotic stenosis,but no dysuria and sexual dysfunction occurred. Local recurrence rate was 5.3%(3/57)in the follow-up period. ConclusionsTotal mesorectal excision with DAIs is not only an effective method to maintain pelvic organ function in lower rectal cancer, but also able to improve the living quality of patients and reduce local reccurence.

Objedctive To study the mechanism of GnRH agalogus(Alarelin)on[ Ca2 + ]; mobilization in stomach smooth muscle cells (SSMc)of rats. Methods Cells were cutured and loaded with Fluo-3-AM. [Ca2 + ]; was measured by nuomeent intensity(FL) in each cell with confocal micoopy. Results (1 ) In Hanks solution. l0-7, l0-6, l0 - 5mol L- 1 Alarelin can elevate[ Ca2 + ], its peak - resting values reached 6. 00 ?0. 50 .9. 23 ?0. 62. l8. 97 ?2. 42 respectively, which indicate that the level of [Ca2+ ]; act in an deede- pendent and time - dependent. (2) thntredly. when Alarelin was 10 4mol?Ｌ－１, its peak - resting value only reached 6. 32 ?0 .67, conpared with Alarelin l0 5m.l L－1 which was sigificantly lower(P 0. 05 ). (5 )When pertreatment with Lacidipine in Hanks solution, the effect of Alarelin l0 5mol L-1.as partly inhibited(P

Nowadays more and more medical study fields need mathematics knowledge.The mathematics abilities of medical students include the ability of basic logic thought,changing medical problems into mathematics ones,understanding and applying mathematics knowledge as well as solving mathematics problems with computers.