OBJECTIVE:To optimize the formula technology of puerarin derivative 4ac-loaded nanoparticles by central composite design. METHODS:4ac nanoparticles were prepared using solvent evaporation method, with mean diameter, encapsulation rate and yield as dependent variables, multi-linear regression and binomial fit were performed on the 3 independent variables at different level:dosages of supporter lactic acid/ glycolic acid copolymer and surfactant polyvinyl alcohol, and the diameter of pinhole. The optimum experimental conditions were predicted by response surface method. RESULTS:The binomial fitting equations of indexes were all superior to their multi-linear regression equations, and the predictive values in the established mathematical model were in good conformity with the experimental values. CONCLUSION:Central composite design plus response surface method shows a good predictability in optimizing the formula technology of 4ac-loaded nanoparticles.

Objective To investigate the effect of experimental benzolism on marrow eryghrocyte micromucleus.Methods Fifty male KunMingmice(KM)were randomly divided into 5 groups:one control group and four experimental groups with 10 mice in each group.The mice were injected subcutaneously with sodium chloride in control group and benzene in experimental groups on every Monday,Wednesday and Friday for four weeks.Four experimental groups were injected with a dosage of 0.5 ml/kg(group B1),1.0 nd/kg(group B2),1.5 ml/kg(group B3) and 2.0 ml/ks(group B4),respectively.Before and after injection of sodium chloride or benzene weekly.weight was measured,and the alteration of erythrocyte micronucleus in peripheral blood and marrow were detected.Results ① Compared to the control group,several indices were partly changed in B1 and B2 groups,while all indices changed significantly in group B3 and B4 groups four weeks after injection(P<0.01).②The erythrocyte micronucleus rate of experimental mice in peripheral blood and marrow showed ascending tendency with the extension of benzene injection phase,peak emerged in the third week and decreased in the fourth week.③In the 4th week,compared to the control group,the alteration of erythrocyte micronucleus in marrow in all experimental groups were significantly increaged(P<0.05).Conclusions Benzolism may induce the increasing of micronucleus rate of mature erythrocyte in peripheral blood and erythrocyte in marrow.which can be used to detect status of being restrained in marrow erythrocyte series.

This paper introduces the design of a linear photoelectric isolating amplifier circuit, and analyzes the errors of the circuit in experiment. The problem of narrow dynamic range in low power isolating circuit is solved.

This article refers to design of signal preprocessing software in the non-contact life parameters detection system,gives details about the composing of software and actualization method of every part,and lists correlative parameters and results.The experiments show that the parameters of this software accord with designed requirements.The software can make high quality signals available for display and process.

This paper introduces the means and characteristics of signal acquisition of the non-contact life parameters detection system as well as the design of preprocessor circuit.The results show that the preprocessor is designed reasonably,which can provide the computer with high quality signals.

The definition, principle, characteristics of micropower Ultra-Wide-Band (UWB) radar are described and discussed in this paper. The human subject is experimented using the UWB radar developed by our team. The experimental results show that UWB radar is able to detect the life signals of the human subject such as respiration and heartbeat without any sensor and electrode touching the subject.The radar can be applied to non-invasive detection of life signals.

Objective To design a circuitry for the indication of the remaining capacity of battery.The circuitry can remind the user of charging in time for normal operation of instruments and prevention of early invalidation due to the over-discharge of battery.Methods The circuitry was designed totally based on hardware which used general electronic components.Results The circuitry functions was dependable and reliable with accurate indication in radar based non-contact life detecting devices.Conclusion The whole design is simple and needs no programming technology.The PCB is small,and the debugging is simple.Moreover,it can be applied to indication of various capacity and voltage.

Objective To solve the signal interference problem by simulation algorithm when clutter signal can bring interference to radar life detecting system and reduce accuracy of its detecting. Methods According to some theory, automatic cancellation model was built up in computer with Matlab software. Results Simulation experiment shows that the cancellation composed signal So(t) is not correlative with the time and precision of auto-counteract but the amplitude and phase of clutter signal. Conclusion The results of the experiment have instructive significance about design of auto-counteract circuit.

BACKGROUND: Previous studies have found that the culture supernatant of the olfactory ensheathing cells is capable of promoting axonal regeneration and functional recovery after spinal cord injury, but there is a lack of research in the field of peripheral nerve. OBJECTIVE: To investigate whether olfactory ensheathing cell culture supernatant is beneficial for nerve repair after peripheral nerve injury. METHODS: Olfactory ensheathing cells were isolated and purified, to prepare the supernatant. The olfactory ensheathing cell culture supernatant was applied to the dorsal root ganglion tissue block in vitro to observe the axon growth of the dorsal root ganglion. The olfactory ensheathing cell culture supernatant was applied to a rat sciatic nerve defect model in vivo to examine its effect on axonal regeneration and myelinization of the injured nerve. RESULTS AND CONCLUSION: The purity of olfactory ensheathing cells was (94.4±3.1)%. Compared with the blank control and low dose olfactory ensheathing cell culture groups, the average length of five longest axons in dorsal root ganglion tissue mass in the high dose olfactory ensheathing cells culture group was significantly increased (P < 0.05). Immunofluorescence showed that the regenerated nerve penetrated through the defect area and the regenerated nerve was arranged orderly in the olfactory ensheathing cell culture and the autologous nerve groups, which was significantly superior to that in the blank control group. Transmission electron microscope observed that the number of regenerated nerve axons and the thickness of myelin sheath in the olfactory ensheathing cell culture group were significantly higher than those in the blank control group (P < 0.05). These results indicate that the supernatant of the olfactory ensheathing cells can promote axonal regeneration after peripheral nerve injury and the myelination of the regenerated axons, which provides a new olfactory ensheathing cells-based acellular therapy for peripheral nerve injury.

Gastrointestinal stromal tumors (GISTs) are commonly seen mesenchymal neoplasms originated from muscularis propria. Small GISTs are the GISTs with tumor size less than 2 cm. With the development of diagnostic technique, more and more small GISTs are found by endoscopy, and the treatment has gradually received much attention. This article reviewed the current status of research, natural history and therapeutic prognoses of small gastric GISTs.