To investigate the angiotensin I-converting enzyme (ACE) inhibitory activity of beta-chain hemoglobin fragments, 17 fragments were synthesized by microwave-assisted solid-phase synthesis method. Wang resin or Trt(2-Cl) resin, Fmoc and HBTU-HOBt were used as solid carrier, N-terminal amino acid protecting groups and coupling reagents, respectively. The ACE inhibitory, alpha-glucosidase inhibitory, antibacterial and antitumor activities of the synthesized fragments were assayed. In vitro, Val-Val-Tyr-Pro-Trp-Thr showed high ACE inhibitory activity (IC50 = 7.42 micromol x L(-1)). The results indicate that there are two active sites in Val-Val-Tyr-Pro-Trp-Thr-Gln-Arg-Phe, one consists of Val-Val-, and the other -Gln-Arg-Phe. Peptides showed high ACE inhibitory activity when the N-terminal was hydrophobic amino acid such as Val and C-terminal tripeptide contained Phe, Trp or Arg. Some of the fragments showed low a-glucosidase inhibitory activity. No antibacterial activity or antitumor activity was detected in vitro. The results indicate that these peptides have a potential antihypertensive effect and possible application in the treatment of hypertension.

Objective To investigate the myocardial protective effect of isehemic post-conditioning in total repair for tetralogy of fallot,in order to improve short-term prognosis of infant patients.Methods 64 cases of TOF infant patients were randomly divided into two groups,32 cases in the control group:conventional surgery without ischemic post-conditioning,and other 32 cases in the experimental group:given three cycles of ischemic post-conditioning.Then the clinical indieators:cardiopulmonary bypass time,aortic cross-clamping time,automatic re-jump rate,the latter parallel to the off-line time,the off-line blood pressure,the offline dopamine usage,extubation time,ICU stay time,postoperative complications,and the testing laboratory indicators:the cTnI and CK-MB levels in plasma after anesthesia induction,10min after aortic cross-clamping,10min after aortic opening,ICU1h,1d after surgery,and 2d after surgery were observed.Results Two patients were died and,mortality rate was 3.1%.The remaining patients were discharged from hospital.Laboratory indicators of the control group and the experimental group had significant differences (all P＜0.05),while the clinical indicators of the two groups had no significant differences(all P＞0.05).But for the sub-group which the aortic cross-clamping time were more than 60min,the clinical indicators were significantly different(all P＜0.05).Conclusion Ischemic post-conditioning could enhance myocardial protection in total repair for tetralogy,of fallot.for the cases aortic cross-clamping time was more than 60min,their clinical meanings were more obvious.

In order to study event-related desynchronization (ERD) related to voluntary movement, we designed two experiments. In the first experiment, untrained subjects were required to imagine the action of typing with left or right index finger for about 1 second before real action, whereas they were required to type instantly after instruction in the second experiment. By analyzing spontaneous EEG signals between the instruction and the action, we predicted which finger was used. The prediction accuracy in the first experiment fell from 85% to 71% with the progress of experiment, the average accuracy being 78%, whereas the prediction result was almost random guess in the second experiment. The results demonstrate that (1) ERD patterns are significantly affected by the effective duration of motion imagination, (2) unconscious reduction of this duration can decrease the prediction accuracy. Therefore, when designing subsequent BCI experiments, we should devote our attention to the question of how to keep the effective duration of motion imagination.
Brain ; physiology ; Cortical Synchronization ; Electroencephalography ; Humans ; Man-Machine Systems ; Task Performance and Analysis ; User-Computer Interface

This paper analyzed the articles from the journal of Chinese Medical Ethics published for 30 years. The results showed that the development of medical ethics in China can be divided into four stages, the incubation period, the slow growth period, the rapid growth period and the stable period;regional distribution was affected by economic development, and the development of medical ethics was also relatively backward in areas where econom-ic development was relatively backward;the number of columns was increasing year by year, the classification tend to be refined, the proportion of each column was fluctuating with the change of the social hotspot, and in recent years, the doctor -patient relationship and medical management and system construction had received more and more attention;and the paper cooperation degree need to be improved, the number of quotations and cited quota-tions steadily improved, and the quality of the paper was improved. Therefore, the government should strengthen policy guidance and standardize the development of medical ethics; the academic level should focus on regional differences and promote academic communication and disciplinary development; and on the individual level, the new medical ethics problem should be concerned, and the research on the hotspots of medical ethics should be car-ried out.

The simulation of excitation propagation's process in human heart is one of the main aspects of ECG forward problem. The simulation results not only are the criterion of the simulation model's precision and reliability, but also have great value in researches and diagnoses. We performed the simulation of QRST waves of complete left bundle branch block (LBBB) and right bundle branch block (RBBB) in virtue of a vector propagation algorithm (VPA), which is accurate, efficient and applicable to anisotropic computer heart models. The simulation results accord with the actual QRST wave in clinical practice.
Algorithms ; Bundle-Branch Block ; pathology ; Computer Simulation ; Electrocardiography ; Humans ; Models, Cardiovascular ; Reproducibility of Results

A high frame rate (HFR) ultrasonic imaging method developed by Jianyu Lu has been attracting attention in the related imaging area. Because a special weighting on the received signal is needed to implement this method, the imaging system is complicated. This paper presents a new kind of theroetical analysis for the HFR imaging system in view of the angular spectrum concept. Based on the study, the special weighting process can be replaced by Fourier transform. Computer simulation demonstrates the correctness of the analysis. It shows that the constructed images by the new method have the same high quality as those obtained by using the original HFR method while the system implementation is greatly simplified.
Computer Simulation ; Fourier Analysis ; Image Processing, Computer-Assisted ; Models, Theoretical ; Phantoms, Imaging ; Ultrasonography ; instrumentation ; methods

Objective:To study the technical and essential steps in laparoscopic selective devascularization with paraesophageal veins-preservation.Methods:To retrospectively analyze the clinical data of 13 cirrhotic patients who underwent laparoscopic selective pericardial devascularization for portal hypertension at the Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial People's Hospital from January 2019 to March 2020. There were 9 males and 4 females with age ranging from 41 to 83 years (median 51 years). The operative time, intraoperative blood loss, postoperative complications and follow-up data were analyzed.Results:All the 13 patients completed theoperation, no patient stopped the operation or transferred to laparotomy. The operation time was (170±32) min.The intraoperative bleeding was (160±30) ml. The postoperative hospital stay was (6.1±1.1) days. There were no complications, including pancreatic leakage and intra-abdominal infection. On follow-up which ranged from 1 to 15 months, one patient developed portal vein thrombosis, no upper gastrointestinal rebleeding.Conclusions:Preservation of esophageal veins in laparoscopic selective devascularization is an accurate surgery which requires close teamwork and rich experience in laparoscopic surgery. The preservation of the main trunk of the gastric coronary vein and integrity of the esophageal veins are the keys to the surgery which is safe and feasible.

The high frame rate (HFR) ultrasonic imaging system, which is developed with limited diffraction beams, constructs images at a high frame rate. However the rectangular imaging area, to some extent, restricts the far field imaging information. At the same time, because of one transmission for constructing image, the system suffers from low SNR. In this paper we present a computationally efficient method to construct sector mode image and to increase the SNR in HFR system. The method uses Golay complementary sequence as excitation to realize two transmission events. Each event simultaneously transmits two plane waves with different transmission angle. Then the received echo signals related to different angle are separated according to orthogonality of Golay complementary sequence and used to construct two images of different area by HFR method. Finally the two images are synthesized to one frame of sector mode image.
Image Enhancement ; methods ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods ; Ultrasonography ; methods

Objective:To analyze the status of secondary maternal and child health hospital accreditation in China and the impact of such accreditation on their service improvement.Methods:The paper used the propensity score matching method to match the accreditation group and the non-accreditation group in 1∶1 ratio, and compared the related indicators of service capability of maternal and child health hospitals between the two groups by non-parametric test and Chi-square test.Results:A total of 842 maternal and child health care hospitals were matched. A comparison was made between the accreditation group and the non-accreditation group, and the differences of the following indicators of individual services within the hospital were statistically significant( P<0.01). These indicators were annual emergency attendance, the number of types of health services for women and children, the utilization rate of beds, the average daily hospital bed of each practicing physician; the following indicators of service management within their coverage were statistically significant: namely the proportion of institutions carrying out health education evaluation within their coverage, that of institutions producing uniform " Mother and Child Health Handbook", that of institutions carrying out information quality control, as well as analysis and utilization.These indicators of the accreditation group were higher than those in the non-accreditation group( P<0.01). Conclusions:Given the role played by maternal and child health institution accreditation in promoting secondary maternal and child health hospital regarding better service content, quantity, efficiency and the quality of business management within their coverage, there is still room for improvement.

Objective: To acquire the main result quality indicators status of tertiary maternal and child health(MCH) hospitals in China, supporting the decision making. Methods: The National Maternal and Child Health Institutions Resources and Operations Survey Direct Reporting System was used to collect the management operation, inpatient death, re-return, hospital-acquired infection, surgical complications and patient safety of these hospitals in China in 2017. Statistical descriptions were made using average, rate and composition comparison data. Results: The proportion of health technicians of tertiary MCH hospitals in China was 83.66%, the average hospitalization days were 5.96 days, with bed occupancy rate of 90.01%. The success rate of neonatal resuscitation was high. Meanwhile, the mortality rate of hospitalized maternal critical illness, the total hospitalization mortality rate of neonatal patients, the incidence of complications in surgical patients, the incidence of neonatal injury and the incidence of birth injury in vaginal delivery were higher in the institutions that had not participated in the MCH hospital accreditation. Conclusions The management of tertiary MCH hospitals in China was in good condition, and the relevant policies and projects have achieved remarkable results. Compared with general hospitals, hospital infection and re-return indicators were good. The quality and safety of tertiary MCH hospitals which have not participated in the MCH hospital assessment were poor. It is recommended to carry out MCH hospital accreditation to improve quality and safety.