In this paper, a novel portable low-frequency electronic pulse analgesia apparatus is introduced, which is based on a novel single-chip microprocessor, switching power supply without transformer and OTL power output amplifier. Through this apparatus, multi-group low-frequency electronic pulses can be produced to simulate the same effects as acupuncture. This apparatus has an observably curative effect for dysmenorrhea.

Objective To segment brain magnetic resonance (MR) images corrupted by noises. Methods We presented a novel Fuzzy C-Means (FCM) algorithm for image segmentation. The algorithm was by modifying the objective function in the conventional FCM. Firstly,by using kernel method,the original Euclidean distance in the FCM was replaced by a kernel-induced distance. Then,a spatial penalty term was added to the objective function to compensate the influence of the neighboring pixels on the center pixel. Results Segmentation results on a four-class synthetic image corrupted by salt & pepper noise shows that the new algorithm is less speckled and smoother. The new algorithm is applied to simulation MR images and is shown to have less misclassification rate than the other FCM-based methods. Conclusion The results of experiments show that the proposed algorithm is more robust to noise than other FCM-based methods.

In many medical instrumentation systems, there exists a long distance between manipulation platform and host unit. Wireless data transferring between the platform and the host could be a feasible way to set parameters. This paper introduces wireless transmitter and receiver circuit based on encoder chip PT2262 and decoder chip PT22720, and presents some typical applications in medical instrument development.

[Objective]To study therapeutic effect of different medicines on motorneuron of spinal cord after explosive injury of spinal cord.[Method]Thirty-six rabbits were randomly divided into model group(group A,n= 12),the dexamethasone experiment group(group B,n= 12) and the methylprednisolone experiment group(group C,n=12),all rabbits were made explosive wound by 0.9 g cyclotrimethylene trinitramine,group A injection NS after blast, group B injection dexamethasone and group C injection methylprednisolone,6 and 24 hours after specimen had been taken out,then morphological change and quantity of the spinal motorneurons be observed under light microscopes.[Result]The reversible change of the neurons of rabbits happened after six hours,after 24 hours,the died motoneuron increase obviously, some rabbits remedied with dexamethasone and methylprednisolone after explosive injury in group B and C,quantity of the died motorneuron marked significant difference than that in the control group(P0.05).[Conclusion]Glycocotical stdroid can protect spinal cord motoneurons after explosive injury of spinal cord.In the experiment,there is no preponderance in early treatment of explosive injury of spinal cord between methylprednisolone and dexamethasone.

OBJECTIVE To get knowledge of the distribution and drug-resistance of Stenotrophomonas maltophilia in our hospital and improve the level of diagnosis and treatment.METHODS The automatic drug sensitive test and the paper spreads medicine sensitive test were carried on to 162 strains of S.(maltophilia) with the index of the VITEK system.RESULTS In all clinical samples,S. maltophilia isolated from phlegm was the most(90%),then was from secretion and swab.The majority of 162 strains were multidrug resistant.But to the(trimethoprim)-sulfamethoxazole and ciprofloxacin,the drug resistance was low((20.4%) and 22.2%,respectively).CONCLUSIONS S.maltophilia is the prevalent pathogen of nosocomial infection in ICU.And most of it are(isolated) from phlegm.So use antibiotics correctly,(reduce) invasive examinations or treatments and strengthen drug-resistant monitoring,are helpful to prevent and control S.maltophilia nosocomial infection.

Objective To develop a hyperthermia temperature control system for the treatment of pelvic inflammatory disease. Methods Temperature was controlled by using PWM method based on a single chip computer. The system was heated by using heating wire. In the whole cycle of T, the heating wire's work time was divided into three different stages according to different temperature of system: in the lower temperature, the duty cycle of the heating wire's work time was 100%; when the system temperature entered to a certain stage, a control variable was obtained through the PID algorithm which was used to compare the difference between the current temperature and the temperature requirements. The control variable determined the duty cycle of the heating wire's work time: the more close to the temperature required for the temperature of system, the duty cycle of the heating wire's work time was more close to 0; if the temperature exceeded a predetermined value, then the heating wire would not heat in the whole cycle. Results The accuracy of the temperature control system was ?0.2 ℃, the overshoot of the temperature control system was ?0.3 ℃, and the response time of the temperature control system was 500 seconds. Conclusion The temperature control method has high precision, small overshoot, and the right response time, which can meet the requirements of constant temperature of hyperthermia treatment. Besides, it is simple and cheap.

BACKGROUND:Buccal Multiloop Removable Appliance can interceptively correct mutiple adolescent malocclusions. But the clinical problem of Buccal Multiloop fatigue fracture is not solved yet. How to prolong the fatigue fracture cycle is stil in the research stage. OBJECTIVE: To study the effect of different temperature of heat treatment on the Buccal Multiloop fatigue fracture cycle, thereby to select a relatively optimal method to enhance the fatigue fracture cycle. METHODS: Thirty-five left HL-2 Buccal Mltiloops were divided into seven groups according to different ways of heat treatment. Each group consisted of five samples. They were an untreated group, three pre-bending groups (320, 420, 520℃ heat treatment before bending) and three post-bending groups (320, 420, 520℃ heat treatment after bending). The dental stainless steel wires and Buccal Multiloop were respectively treated by low-temperature annealing. The data were recorded and evaluated after the samples tested by the 3D Simulating Movement of TMJ Testing Machine. The features of fatigue fracture were observed by scanning electron microscope. RESULTS AND CONCLUSION: The mean values of the Buccal Multiloop fatigue fracture cycle from largest to smalest were as folows: 520℃ pre-bending group > 420℃ pre-bending group > 320℃ pre-bending group > untreated group > 520℃ post-bending group > 320℃ post-bending group > 420℃ post-bending group. The fatigue fracture cycle of Buccal Multiloop made of the dental stainless steel wires after 520℃ annealing treatment was longer than others. By the observation of scanning electron microscope, the fracture crack extension area had the tendency to expand, transient interruption was delayed and the tissue structure became more uniform.

BACKGROUND:The self-ligating bracket is superior to the conventional bracket in orthodontic treatment, but there are a lot of controversies. At present, researchers have different views on the function of self-ligating brackets. OBJECTIVE:To summarize the comparative study of self-ligating brackets and conventional brackest with the direction and development in recent years. METHODS:A computer-based search of PubMed (2000-2014) and CNKI (2000-2014) databases was done for relevant articles, using the key words of “self-ligating brackets; conventional orthodontic brackets” in English and Chinese, respectively. RESULTS AND CONCLUSION:Self-locking brackets saves chair side time, which has been confirmed and accepted. There are different views for the issue that self-ligating brackets can reduce friction in orthodontic treatment. It is widely accepted that, the self-ligating brackets using thin round wire had less friction than the conventional brackets; whether the friction of self-ligating brackets in the closed gap and fineness adjustment stages is less than the conventional brackets stil remains unclear, which need further clinical comparative studies. The self-ligating brackets showed no significant difference with the conventional brackets in arch expansion, reducing anchorage loss and root adsorption. The majority of relevant studies is performedin vitro, and cannot exactly simulate the dental conditions. A large-size experiment with the uniform criteria for therapeutic efficacy is needed to objectively evaluate self-ligating brackets.

This paper introduces a programming cardiac trigger apparatus used for the study of quantitative measurement of myocardial blood flow with myocardial contrast echocardiography.The design of hardware circuit based on MCU and the scheme of software based on Keil C51 are mainly discussed.With stable and reliable working,this apparatus provides a kind of technical support for the study of quantitative measurement of myocardial blood flow with continuous intravenous injection of sonicated microbubbles.

Objective To design an instrument that can provide a series of pulse to stimulate cell by means of external electric field, the structure and function of organism can retrieve. Methods AVR MCU, produced by America ATMEL Co., is used as the core of the system. The program has been developed to adjust three pulse's parameters, including amplitude, frequency and pulse duration. The cooperation between DAC and OP completes the transformation from monopole pulse to bipolar pulse. The booster PB50 amplifies the current and voltage of the output. Results The Stimulator can provide bipolar pulse, amplitude: up to ?40V, frequency: 0.01Hz -10Hz, pulse duration: 0.4ms -24ms. Conclusion Cooperating with special electrode board, the instrument can provide effective electric field for cell simulating. At present the instrument has been used in the research of the endothelial progenitor cell.