1.In vitro fracture resistance of endodontically treated anterior teeth with varying ferrule heights and configurations with glass-fiber post
Yachong WANG ; Yunzhi FENG ; Mei CHEN
Journal of Practical Stomatology 2010;26(1):126-127
The extracted human maxillary central incisors were endodontically treated and restored with glass-fiber post. Then they were randomly divided into four groups and tested. Results showed that groups with ferrule more than 2 mm had higher fracture resistence than others.
2.A in vitro study of coronal microleakage of different post and cement systems
Yunzhi FENG ; Mei CHEN ; Yachong WANG
Journal of Practical Stomatology 2009;25(4):482-485
Objective: To compare the coronal sealing abilities of different post and cement systems through measuring the value of leakage by using dye method. Methods: Fifty human mandibular premolars with single canal were divided into 6 groups randomly. A group: roots sealed by temporary material, B group: roots restored with fiber post adhered with composite resin cement, C group: roots restored with casting metal post and core adhered with composite resin and zinc phosphate cement, D group: positive control, E group: negative control. After finishing preparation and restoration of roots, microleakage was determined by using dye method. Results: The groups restored with any post and core system produced significantly less microleakage than temporary material sealing group(P<0.05). But no differences were detected between two groups bonded with the composite resin cement (P>0.05). Posts adhered with zinc phosphate luting agent produced more leakage than those with composite resin cement(P<0.05). Conclusion: Luting agent can decrease the coronal microleakage. Composite resin cement provides better sealing ability.
3.Research on function of Multi-channel Brain Magnetic Stimulation Machine in auditory memory
Mei XU ; Xuemin WANG ; Feng CHEN
Chinese Medical Equipment Journal 2003;0(12):-
Objective:To check the clinical effect of Multi-channel Brain Magnetic Stimulation Machine.Method:Sixteen volunteers are divided into two groups.Members of the first group which is the corresponding group listen to news material in the sober state and then answer the questionnaire.At last their EEG is collected.Members of the second group listen to the same material in the sober state and they are stimulated at the forehead and temporal area by Multi-channel Brain Magnetic Stimulation Machine at the same time.They also answer the questionnaire under the magnetic stimulation at forehead and their EEG is collected,too.Result:Answers of the second group are obviously better than the first group.The power spectrum of EEG at the forehead,temporal,parietal region and even the whole brain area in the first group is stronger than that of the second.Conclusion:Multi-channel Brain Magnetic Stimulation Machine excites brain in a way and then helps people complete the job better.
4.Relationship between early brain damage in preterm infants detected by magnetic resonance imaging and neurodevelopmental outcome
Mei CHEN ; Shulan LI ; Zijian FENG
Chinese Journal of Perinatal Medicine 2013;(5):278-283
Objective To investigate the relationship between early brain menifestation such as white matter damage and ventriculomegaly detected by magnetic resonance imaging(MRI) and adverse neurodevelopmental outcome in preterm infants.Methods From March 15,2007 to April 12,2011,122 preterm infants accepted MRI examination 8-14 days after birth in Chinese People's Liberation Army 202 Hospital.Totally,115 preterm infants were followed up at 12 months old and mental development index(MDI) and psychomotor development index (PDI) score were measured.MDI<70 was as mental dysfunction,-84 as borderline dysfunction and-114 as normal; PDI<70 was as psychomotor dysfunction,-84 as borderline dysfunction and-114 as normal.The relationship between clinical characteristics of preterm infants,MRI abnormalities and neurodevelopmental outcome were analyzed by analysis of variance,LSD and Kruskal-Wallis H test.Results The 122 premature infants included 69 males and 53 females with the median gestational age of 32 weeks(28-36 weeks)and the median birth weight of 2050 g (1270-3110 g).In 24 premature infants with mentaldysfunction,the average gestational age [(28.7 ± 1.7) weeks],birth weight[(1520.1-44.8) g] and 1 min Apgar score (5.5 ± 0.8) were all lower than those in normal infants [n =59,(33.5 ± 2.2)weeks,(2240.4 ± 47.1) g and 7.1 ± 0.8],while the average mechanical ventilation time was longer [(20.4±5.8) dvs (5.6±2.7) d](t=2.37,2.49,2.13 and 2.44,P<0.05).In 20 premature infants with psychomotor dysfunction,the average gestational age [(27.9 ±± 1.4) weeks],birth weight [(1515.6±43.7) g],1 min Apgar score (5.6t0.5) were lower than those in normal infants [n=62,(33.2±2.4) weeks,(2264.3±42.5) g and 7.2±0.6],while the mechanical ventilation time was longer [(18.2±4.7) dvs (5.3±2.2) d](t=2.28,2.52,2.09 and 2.38,P<0.05).Among thirteen preterm infants with severe white matter damage,eleven and nine developed mental or psychomotor dysfunction respectively.Among eleven preterm infants with moderate and severe ventriculomegaly,seven and six developed mental or psychomotor dysfunction respectively.The more severe the white matter damage and ventriculomegaly,the higher the incidence of mental (H=16.23 and 14.33,P<0.05) and psychomotor dysfuction (H =18.63 and 12.69,P < 0.05).Conclusions White matter damage is common in preterm infants.Prognosis of preterm infants with mental and psychomotor dysfunction is related with the degree of white matter damage and ventriculomegaly.
5.Study on bonding interface and microstructure of different resin composite inlays
Yaming CHEN ; Hailan FENG ; Lei MEI
Journal of Practical Stomatology 1996;0(02):-
Objective:To evaluate the characteristics of bonding interface and microstructure of different resin composite inlays. Methods:Different composite resins and adhesives were used for restoration of extracted molars, the results were evaluated under scanning electron microscope(SEM) and atomic force microscope(AFM).Results:The microstructure feature of Tescera was with higher density when compared with that of other conventional resins,and fewer small holes could be seen in Tescera. AFM pictures showed that Tescera was with a very smooth surface. Indirect composite resin could be combined with resin bonding agent tightly and infiltrated each other. The interface between direct resin inlay material and resin bonding agent was very clear,and no obvious interfiltration could be seen under SEM and AFM. Conclusion:After treatment with water, heat,light and pressure, the physical properties of indirect composite resin is improved effectively, and obvious infiltration can be found in the interface.
7.HPLC analysis of the constituents of Radix Puerariae absorbed into blood
Mei ZHANG ; Feng QIU ; Xuejun XIE ; Jing LIU ; Xiao CHEN
China Journal of Traditional Chinese Medicine and Pharmacy 2005;0(03):-
Objective: To sieve the bioactive constituents of Radix Puerariae,serum pharmacochemistry research was performed.Method: Based on the establishment of HPLC fingerprints of Radix Puerariae,the constituents absorbed into blood were determined by comparing the HPLC fingerprints of the methanol extracts,tested serum samples and blank serum sample.Results: Four compounds absorbed into blood were detected,among which two were original constituents of Radix Puerariae(including puerarin),the other might be metabolites of the original constituents.Conclusion: These four constituents absorbed into blood were possible bioactive components of Radix Puerariae.Further studies on them will help clarify the bioactive constituents and mechanisms of Radix Puerariae.
8.Design for a phase Ⅳ study on perioperative intervention with nebulized ipratropium bromide in Chinese patients with chronic obstructive pulmonary disease
Bao CHEN ; Feng FAN ; Baihan FU ; Mei MAO ; Tao ZHANG
Chinese Journal of Thoracic and Cardiovascular Surgery 2017;33(3):175-178
Owing to the increasing morbidity and pulmonary infection,management of pulmonary function has become an important problem for COPD patients who undergo surgery.Surgical patient with respiratory disease such as COPD has declined lung function before operation,then increased the risk of post-operative pulmonary complications.Ipratropium bromide can significantly improve pulmonary function.Therefore,we hypothesis the treatment with nebulized ipratropium bromide will benefit the perioperative patients with COPD.A randomized,double-blind,placebo-controlled,parallel-group,multi-center trial (Ipratropium bromide in Peri-Operative COPD study,IPO-COPD study)has been conducted to evaluate the efficacy and safety of nebulized ipratropium bromide in Chinese perioperative patients with COPD under general anaesthesia.A total of 192 COPD patients who satisfied the eligibility criteria were randomly assigned(1∶1) to one of the two treatment groups(ipratropium bromide 500 μg or normal saline 4 ml) for 11 days.Measurements will include the change of the forced expiratory volume in 1 second(FEV1),the forced vital capacity(FVC),blood gas analyses and main post-operative pulmonary complications.
9.The influence of CYP4F2(rs2108622)gene polymorphism on the warfarin dose in old patients
Mingjuan TAN ; Weiwei CUI ; Feng CHEN ; Yanping MEI ; Yingdong GAO
International Journal of Laboratory Medicine 2014;(11):1400-1401,1404
Objective To observe the effect of CYP4F2(rs2108622)polymorphism on the dose of warfarin in old patients(65 to 75 years old)who were treated with atrial fibrillation.Methods Sixty cases of old patients with atrial fibrillation were enrolled in the study.All the subjects had taken warfarin for 3 months,and the international normalized ratio(INR)maintained between 1.6 and 2.5.And the CYP4F2(rs2108622)variant were detected by PCR.Results The patients with CYP4F2(rs2108622)allele C/C scored significantly lower warfarin dose than patients with variant allele C/T and T/T (P < 0.05 ).Conclusion CYP4F2 (rs2108622)gene polymorphism have been related with warfarin dose in old patients.
10.Incidence of depression in patients with advanced malignancy and its effect on quality of life
Mei YE ; Zhengzhi FENG ; Keyu LIU ; Huoming CHEN
Cancer Research and Clinic 2013;(4):260-262
Objective To investigate the incidence of depression in patients with advanced malignancy and its effect on quality of life.Methods Patients with advanced malignancy were evaluated with Beck depression and quality of life questionnaires.The correlation of Beck depression scoring with quality of life was analyzed.Results A total of 230 in-patients with advanced malignancy were enrolled in this study and 213 copies of valid questionnaire were collected.95.3 % (203/213) patients had depression.The Beck depression scoring had positive correlation with body,role,mood,cognition,society,vomiting,pain,dyspnea,agrypnia and appetite (all P < 0.05),and had negative correlation with total health factors (r =-0.296,P < 0.01).Conclusion Depression is prevalent in patients with advanced malignancy and correlated with quality of life.Therefore,psychological interventions are needed to relief depression and improve quality of life.