Objective To provide a reliable experimental model for gastroesophageal reflux (GER) study. Methods Twenty Japan 5-month-old male rabbits wererandomly divided into two groups: group cardiomyotomy(n=10), group partial cardiomyectomy(n=10). The operations of cardiomyotomy and parital cardiomyectomy were performed in 2 groups respectively. All the animals underwent intraesophagealpH detection 1 week before operation and 4 weeks after operation. The mean changes of reflux ratios were compared between before operation and after operation.Results In gastroesophageal reflux ratio between before operation and after operation, there was no significant difference in group cardiomyotomy (1.98%±1.52% and 4.32%±2.39%, Pgt;0.05) and there was significant difference in group partialcardiomyectomy（1.56%±1.57% and 13.56%±3.27%, Plt;0.05）. Conclusion The reliable experimental model of GER can be made with procedure of partial cardiomyectomy. It can be used in estimating the operative procedure of antireflux and is conducive to dynamic observation and study of esophagitis.
ObjectiveTo figure out the factors affecting the prognosis of liver transplantation and the research progress on methods for predicting the prognosis of liver transplantation so as to provide guidance and reference for the distribution of liver sources and the perioperative treatment of liver transplantation.MethodThe literatures related to the factors influencing the prognosis of liver transplantation and the methods in predicting the prognosis were searched in the PubMed, CNKI, Wanfang, and other databases and the results were analyzed and summarized.ResultsThe liver transplantation was an effective method in the treatment of end-stage liver diseases. The main factors affecting the prognosis of liver transplantation included the change of internal environment, systemic inflammatory response, and general systemic conditions. On the basis of Model for End-stage Liver Disease (MELD), the new prediction model built in combination with the blood sodium ion, lactate, muscle mass, or reticulocyte count and hemoglobin concentration had improved the prognostic prediction ability of liver transplantation.ConclusionsIt is possible to predict the prognosis of patients with liver transplantation more accurately by selecting a more targeted prediction model combined with the factors affecting the prognosis of liver transplantation. It might provide a reference for perioperative management and treatment and make the limited liver source play the most role and save more lives.
Objective To establish the model of pancreatoduodenal allotransplantation in pigs with enteric drainage (ED) and portal venous drainage (PVD). Methods Forty-six hybrid landraces were divided into two groups (donor and recipient groups) randomly, for pancreatoduodenal allotransplantation. Donors were perfused via abdomial aorta without clamping the portal venous outflow with UW solution after heparinization. Whole pancreatoduodenal graft was arvested with segments of abdomial aorta and portal vein and shaped under cold UW solution. Then, the end-to-end nastomosis was performed with the donor iliac artery bifurcation “Y” graft to the recipient superior mesenteric arteries and celiac artery. Furthermore, type Ⅰdiabete model was made by removal of the recipient pancreas. The venous anastomosis was reconstructed between the donor portal vein and the recipient superior mesenteric vein. Meanwhile, the end-to-side anastomosis was performed with the donor common iliac artery bifurcation “Y” graft to the recipient abdomial aorta and the side-to-side intestinal anastomosis was performed between the donor duodenum and the recipient jejunum. External jugular vein was intubated for transfusion. The levels of blood glucose， insulin and glucagon in blood were measured before and during the operation and 1， 3， 5， 7 d after operation. Results Twenty-three cases of pancreatoduodenal allotranplantations were performed on pigs. One died from complication of anesthesia. Success rate of operation was 95.7％.Complications of operation happened in 2 cases in which one was phlebothrombosis, incidence 4.5％and the other was duodenojejunal anastomotic leak, incidence 4.5％. The level of blood glucose increased within 30 min and recovered on the 2nd day after removal of pancreas. The levels of insulin and glucagon decreased within 30 min and recovered on the 2nd day after removal of pancreas. Rejection curred at the 1st day and reached the worst level on the 9th day after transplantation without the change of insulin and glucagon in blood and clinical symptoms of rejection. Conclusion Pancreatoduodenal transplantation in pigs can treat type Ⅰ diabete. ED and PVD can keep the function of endocrine in normal. The technique of duodenal transplantation with ED and PVD may pave the way for the further development of pancreas transplantation in clinic.
Taking advantages of the sparsity or compressibility inherent in real world signals, compressed sensing (CS) can collect compressed data at the sampling rate much lower than that needed in Shannon’s theorem. The combination of CS and low rank modeling is used to medical imaging techniques to increase the scanning speed of cardiac magnetic resonance (CMR), alleviate the patients’ suffering and improve the images quality. The alternating direction method of multipliers (ADMM) algorithm is proposed for multiscale low rank matrix decomposition of CMR images. The algorithm performance is evaluated quantitatively by the peak signal to noise ratio (PSNR) and relative l2 norm error (RLNE), with the human visual system and the local region magnification as the qualitative comparison. Compared to L + S, kt FOCUSS, k-t SPARSE SENSE algorithms, experimental results demonstrate that the proposed algorithm can achieve the best performance indices, and maintain the most detail features and edge contours. The proposed algorithm can encourage the development of fast imaging techniques, and improve the diagnoses values of CMR in clinical applications.
Objective To explore the effect of oxygen inhalation on the retinae of newborn rats and its mechanism.Methods We mimicked the retinopathy of prematurity(ROP) by putting the newborn rats in high concentrated oxygen. One-day old rats were put into the oxygen box with the oxygen concentration of 80% for continuous 7 days; then in air condition for 7 days. The arterial blood oxygen pressure, retinal superoxide dismutase (SOD), and malondialdehyde (MDA) of the rats (1,2,4,7,8,9,11,14 days old) were examined. The diameter of retinal vessels′main branch and the coverage rate of peripheral vessels were measured in 7- and 14-day-old rats by ink perfusion. The retinal neovascularization of rats (8,9,11, 14 days old) were observed by HE staining. The rats of the same age fed in air condition were in the control group.Results The differential pressures of blood oxygen of rats (1,2,4,7 days old) in study group were significantly higher than those in the control group (P＜0.01), while the differential pressures of blood oxygen of rats (8,9,11,14 days old) in study group were lower than those in the control group (P＞0.05). The contents of SOD of the retinae in the rats ( 1,2,4,7,8 days old) were significantly lower than those in the control group(P＜0.01, P＜0.05 ), while the contents of MDA were significantly higher than those in the control group (P＜0.01,P＜0.05). The diameter of retinal vessels′main branch in 7-day rats was 75% of the control group, and the coverage rate of peripheral vessels was 22% of the control group; and was 61% and 73% respectively in 14-day-old rats. The neovascularization could be seen in 16.7% of the rats in the study group and nought in the control group.Conclusion The damage of free radical of the retina in high concentrated oxygen and hypoxia situation after oxygen supply may be one of the most important mechanism of ROP. (Chin J Ocul Fundus Dis，2003，19：269-332)
The effect of relaxation time in hyperbolic heat transfer model on the temperature field of microwave ablation of atrial fibrillation was investigated. And the results were compared with those calculated by Pennes model. A three-dimensional model of microwave ablation of atrial fibrillation was constructed. The relaxation time (τ) was 0, 1, 5, 8, 10, 15 and 20 s, respectively. And the temperature field of myocardial tissue was obtained. The results showed that the highest temperature of the hyperbolic model was 21.8 ℃ lower than that of the Pennes model at the beginning of ablation. With the increase of ablation time, the highest temperature tended to be the same. The lesion dimensions appeared at 3, 4, 6, 7, 8, 9, and 10 s, respectively after ablation. Therefore, the influence of hyperbolic model on temperature will decrease with the increase of the ablation time. At the beginning of ablation, the relaxation time will hinder the speed of myocardial thermal diffusion. The larger the relaxation time is, the slower the speed of thermal diffusion is. This study provides a reference for the application of hyperbolic model in microwave ablation of atrial fibrillation.
Objective To introduce the research progress in the immune of composite tissue allotransplantation. Methods The related articles were reviewed to summarize the immune characteristics, experimental developments, and cl inical experiences of composite tissue allotransplantation. Results Composite allogeneic tissue is on the body surface, including the composition of the complex with high antigenicity. There are a lot of differences in the immune responsesbetween composite tissue allotransplantation and organ transplantation, such as immunosuppressant protocol, rejectiondiagnosis, and chronic rejection. Conclusion In the next study, it is urgently needed to learn these experiences and toestabl ish the special standard of composite tissue allotransplantation in induction of immune tolerance, local medication, and rejection diagnosis.
Purpose To investigate nucleoside diphosphate kinase (NDPK ) expression of tumor metastasis suppressor gene nm23 in heterotransplanted model of retinoblastoma(RB) in nude mice，and analyse the correlation between the expression of nm23 gene and the formation and progression of heterotran splanted RB． Methods SP immunohistochemical method was used to detect the expression of nm23 gene product NDPK in 20 tumors of heter otransplanted RB model and normal retinal tissue． Results The negative staining of nm23/ NDPK was found in normal retinal tissue , whereas 100% expression rate in RB tumors with positive number of 48.73plusmn;2.37． No statistical significance of the expression of nm23/ NDPK was observed between the intraocular growth phase （I～Ⅲ grade） and invasive phase （ Ⅳ～Ⅴ grade）in heterotransplantedRB tumors． Conclusion The function of nm23 gene as a tumor metastasis suppressor in heterotra nsplanted RB tumors was less prominent ,but it may play a role in carcinogen esis and progrssion of RB and may predict poor prognosis． (Chin J Ocul Fundus Dis, 2001.17:47-49)
Objective To further investigate pathologic mechanism of retinal phototrauma. Methods Twenty Wistar rats were divided into control and experimental groups.Their eyes were extracted in 12，24 and 36 hours after light exposure.HE stained retina samples were examined and TDT-mediated dUTP nick end labelling(TUNEL)method was employed to distinguish apoptotic cells. Results After 12-hour light exposure,slight vesiculation was observed in the rod outer segment of the retinas.After 24-hour light exposure,the outer nuclear layer showed predominant fractured and condensed nuclei and fragmented DNA.After 36-hour light exposure,the rod outer and inner segments were lysed and most of the nuclei in the outer nuclear layer were disappeared. Conclusions Apoptosis of photoreceptor cell is one of the important mechanisms which cause experimental retinal photoinjury of rats. (Chin J Ocul Fundus Dis, 1999, 15: 167-169)