Objective To evaluate the dynamic viscoelasticity of unpolymerized light-cured composite resins reinforced with retentive filler(RF)or normal filler(NF),and the effect of dynamic viscoelasticity on clinical manipulation.Methods The dynamic viscoelastic properties of two light-cured composite resins reinforced with RF or NF were measured respectively with the dynamic stress rheometer.Flowing property,filling capacity,shaping and stability were designed to describe the clinical manipulation of the composites.Results The dynamic viscoelastic behavior of the composites is sensitive to changes in frequency,composite resin reinforced with RF had significantly higher shear storage modulus(G')and shear loss modulus(G″)than composite resins reinforced with NF,and had significantly lower loss tangent(tan?).The former was found to be more viscous,and the latter was found to be more elastic.Clinically,composite resin reinforced with RF has a greater ability of stability and shaping,and a lower potential for deformation;composite resin reinforced with NF has a higher flowing ability,and with a good adaptation to the cavity of the tooth.Conclusions The ideal composites should have high G' and low tan?.

OBJECTIVETo investigate molding technology of total alkaloids from Sophora alopecuroides freeze-dried powders and observe its inhibition effects on liver transplantation tumor in mice.

METHODWith color, clarity, water-soluble and formability as indexes, single factor tests were adopted to screen type and amount of filler, the concentration of total alkaloids in drug liquid, pH in order to determine optimum prescription of total alkaloids from S. alopecuroides freeze-dried powders, the lowest melting point was determined and freeze drying curve was drafted. Mice hepatoma H22 ascites tumor strain was sterile inoculated in right axillary subcutaneous of mice, and antitumor effect of total alkaloids from S. alopecuroides freeze-dried powders on liver transplantation tumor H22 in mice.

RESULTWhen selected 80 g x L(-1) as mannitol as filler, the concentration of total alkaloids in drug liquid was 25 g x L(-1) and pH 6.5-7.5, freeze-dried effect was optimum with fast reconstitute speed. Average inhibition rate of the big (120 mg x kg(-1)) and medium (60 mg x kg(-1)) dose group of total alkaloids from S. alopecuroides freeze-dried powders on liver transplantation tumor H22 in mice were 56.08% and 35.49%, respectively.

CONCLUSIONPreparation technology was reasonable, reproducible and stable, total alkaloids from S. alopecuroides freeze-dried powders had significant antitumor effect and showed a dose-effect relationship.

Alkaloids ; chemistry ; pharmacology ; Animals ; Antineoplastic Agents, Phytogenic ; chemistry ; pharmacology ; Cell Line, Tumor ; Color ; Freeze Drying ; Humans ; Liver Neoplasms ; drug therapy ; Mice ; Powders ; chemistry ; Sophora ; chemistry ; Tumor Burden ; drug effects

AIM: To evaluate the case-based learning ( CBL ) in ophthalmology teaching practice.
METHODS: A total of 88 students were taught by the combination of lecture-based teaching with CBL form of sensory organs in Jinzhou Medical Teaching Classes. After class, the questionnaire was filled by each student to evaluate the CBL teaching mode.
RESULTS:The description of the data was analyzed as a percentage of each option. All the students were taught by CBL at the end of the class, most of the students could accept the teaching mode, it was helpful for students to understand the principle of clinical treatment, increased the interest in the process of teaching. And it was conducive to review the knowledge and exercise clinical case analysis ability. And it could recognize the ophthalmic diseases and special auxiliary examination. CBL teaching mode could stimulate students' interest in learning ophthalmology, it was beneficial to the cultivation of theory combined with practice and clinical thinking.
CONCLUSION: CBL teaching mode can be used as an auxiliary teaching lecture-based learning teaching.

ObjectiveTo investigate synergistic effect of donor livers blocked by recipient blood serum (RS) and cobra venom factor (CVF) treatment to inhibit hyperacute rejection (HAR) happened in liver xenotransplantation.MethodsThe SD rat blood serum was prepared for pre-perfusing the donor livers before experiment.24 pairs of guinea-pig (GP) and Sprague-Dawley (S.D.) rats were choiced respectively and pair-matched between GP donor and rat recipient randomly.Before transplantation,donor livers of GPs were pre-perfused by 0.5％ SD rat serum.Paired animals were divided into 4 groups randomly such as donor liver perfused by RS,recipient treated by CVF,RS+ CVF performed and Ringer solution as a control.The orthotopic liver xenotransplantations was performed with two-cuff technique.The survival time and liver function of recipients,morphological and pathological changes of rat livers were observed.ResultsThere was no piebaldism change on the recipient liver from experimental group.The survival time of recipients from RS+CVF group [(161.5±30.9) min]was longer than that of control[(45.2 ± 13.9) min] and CVF[(125.2 ± 25.5) min] or RS groups [(88.1±19.7) min] (P＜0.05).The ALT in serum of recipients from RS+CVF [(63.2±13.9)U/L]was lower than that from congtrol group [(126.1±23.3)U/L](P＜0.01) and CVF group [(79.9±18.1)U/L](P＜0.05) or RS group [(106.1±19.3)U/L](P＜0.01) The histological damages including thrombosis,interstitial bleeding and edema of recipient liver from RS+CVF group were alleviated markebly than that of other groups (P＜0.05).ConclusionThere was a synergistic effect to inhibit HAR happened in liver xenotransplantation by blocking the donor liver with recipient blood serum and CVF treatment significantly.

Multi-channel recording is now a widely used tool in neuroscience research that makes it possible to study the activity of neuron population. The data collected from multiple neurons indicate important information of neural coding rules and brain functional mechanism, which requires advanced computational techniques to decode. Here we reviewed the methods for multi-channel neural data analysis and gave brief introduction of their typical application for studying different kinds of neural data.
Animals ; Brain ; cytology ; physiology ; Database Management Systems ; Humans ; Models, Neurological ; Nerve Net ; physiology ; Neurobiology ; methods ; Neurons ; physiology ; Signal Processing, Computer-Assisted

OBJECTIVETo determine the rheological properties of the photo-polymerized composite resin reinforced with retentive filler (RF) and its rheological difference with normal filler (NF) composite resin.

METHODSRheological properties of the composite resins, such as viscosity, shear stress and creep compliance, were measured with dynamic stress rheometer at room temperature (25 degrees C).

RESULTSThe viscosity of the composite resin reinforced with RF is higher than that of NF composite resin (P < 0.01); at the beginning, the viscosity of the former has little change with the rising of shear stress and the latter decreases, then the viscosities of the two composite resins increase with the rising of shear stress as soon as over 203.18 Pa of shear stress; the creep compliance of the composite resin reinforced with RF is significant smaller than that of NF composite resin (P < 0.01).

CONCLUSIONSThe rheological properties of the two composite resins have significant difference, so they have different clinical using properties.

Composite Resins ; chemistry ; Dental Restoration, Permanent ; Viscosity

BACKGRoUND:The clinical manipulation properties of light-cured composite resin,such as flowing property.filling capacity,shaping and stability has not unified definition in dental materials notwithstanding more studies of rheological behaviors were undertook.OBJECTIVE:To explore the dynamic viscoelasticity difference of unpolymerized light.cured composite resins with retentive filler or normal filler,and to investigate effect on the clinical manipulation properties of rheological behaviors in two light-cured composite resins to define an ideal resin.DESIGN,TIME AND SETTING:This controlled study is a correlation study of integrating the base study and clinical use.Basic study was performed in January 2003 at Key Laboratory of Engineering Plastics of Chinese Academy of Sciences in Beijing.The clinical observation study was conducted at the Stomatology Center,Haikou People's Hospital until December 2006.MATERIALS:Light-cured composites employed in this study were reinforced with RF(experimental composite resin I,ECR-Ⅰ)or NF(experimental composite resin Ⅱ,ECR-Ⅱ),which were supplied by Dental Materials Laboratory.Medical College of Stomatology of Peking University.They contained different types of fillers,but had the same resin matrix and volume percent of filler.METHODS:The dynamic viscoelastic properties of ECR-Ⅰ or ECR-Ⅱ were measured respectively with the dynamic stress rheometer DSR-200 in a room maintained 25℃.Flowing property,filling capacity,shaping and stability property were employed to assess the clinical manipulation property of ECR.MAIN OUTCOME MEASURES:Viscoelasticity(G',G",tan δ)and clinical manipulation of two kinds of compound resins.RESULTS:The dynamic viscoelastic behavior of the two composites was sensitive to changes in frequency.ECR-Ⅰhad significantly higher G'than ECR-Ⅱ.ECR-Ⅰ had a greater ability of stability and shaping.and a lower potential for deformation clinically.ECR-Ⅱ had significantly higher G"than ECR-Ⅰ.and ECR-Ⅱ had a higher flowing ability clinically.ECR-Ⅱ had significantly higher tan δ than ECR-Ⅰ.ECR-Ⅱ was found to be more viscous and better filling capacity,with a good adaptation to the cavity of the tooth clinically.CONCLUSION:The dynamic viscoelasticity(G',G",tan δ)and clinical manipulation properties of ECR-ⅠI or ECR-Ⅱ are compared.The ideal composites should have higher G'and lower tan δ

Objective To evaluate the embolic effect on rabbits arteries using self-made copper plated platinum coil.Methods 1 7 New Zealand Big Ear Rabbits were selected.Unilateral subclavian artery or carotid artery was embolized with self-made secondary level copper plated platinum micro-coils (experimental group)through 3F-catheter.Contralateral subclavian artery or carotid artery was also embolized using secondary level platinum micro-coils (control group)as a control.The level of serum copper ions and the liver and renal function were recorded during different intervals before and after embolization.The arteriography and the tissue his-tology were observed respectively during different intervals after the embolization.Results 1 5 of 1 7 rabbits were embolized success-fully.After embolization,the level of serum copper ions increased in 2 weeks(P <0.05).However,it returned to preoperative level after 4 weeks (P >0.05).The liver and renal function was similar to that of the preoperation after 2 weeks.After embolization,an-giography showed that vascular embolization effect between two groups was not significantly different at 10 min and 30 min;howev-er,the embolization effect of experimental group was superior to that of control one (P <0.01)at 3 days and 1 week,2 weeks,4 weeks,6 weeks and 12 weeks.Pathological results showed that there were a lot of thromboses inside,outside and around the copper coil.Few thromboses appeared around platinum coil in control group.The thrombosis situation in experiment group was better than that in control one (P <0.01).However,no significant difference in inflammatory cell infiltration between two groups was found. Conclusion Self-made secondary level copper plated platinum coil has good physical property,rememorability,flexibility and con-trollability.

Objective To evaluate the correlation between CT perfusion blood volume (Lung PBV)and the degree of pulmonary embolism by CT pulmonary angiography (CTPA).Methods 1 65 patients with suspected pulmonary embolism underwent dual-ener-gy CT angiography,then the Lung PBV iodine distribution was analyzed by using a software algorithm.Consistent CTPA results evaluated by two experienced radiologists were taken as standard reference.After two months,the CTPA images were assessed by other two radiologists at random.The position and the number of perfusion defects,and (or)hypoperfusion were recorded.Results Of all 1 65 suspected patients,41 were diagnosed as pulmonary embolism with involved 1 64 segment arteries including part occlusion in 56 and complete occlusion in 108.Lung PBV showed perfusion defect in 141 pulmonary segment including 42 in patients with part occlusion and 99 in ones with complete occlusion.1 7 pulmonary segments were misdiagnosed with part occlusion in 9 and complete ones in 8.23 segments were misdiagnosed including part occlusion in 14 and complete ones in 9.The perfusion defect of Lung PBV was correlated to CTPA moderately or well (to part occlusion with r =0.508 and P =0.022;to complete ones with r =0.905 and P =0.000).Conclusion Dual-energy lung perfusion imaging is helpful for accurate assessment of abnormal blood flow distribution caused by pulmonary embolism,and improve the diagnosis.