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find Keyword "Model" 54 results
  • Application and Significance of MELD Scoring System in Liver Transplantation

    【Abstract】Objective To introduce the birth and development of model of endstage liver disease (MELD) and evaluate its effect on liver transplantation(LT) as a new scoring system. Methods Literatures of MELD applied in LT were analyzed retrospectively. Results MELD scoring system was used for predicting the prognosis of patients with endstage liver disease and the death risk of candidates on waiting LT extensively and the order of organ sharing was determined by its predicable results. Conclusion MELD has been had a successful initial implementation for predicting the shortterm survival probability and mortality in patients with endstage liver disease, and meeting the goal of providing a system of allocation that emphasizes the urgency of the candidate while diminishing the reliance on waiting time, which has been proven to be a powerful tool for auditing the liver allocation system.

    Release date:2016-08-28 04:28 Export PDF Favorites Scan
  • Research of Partial Liver Transplantation with Hepatic Arterialization in Rats

    ObjectiveTo develop and modify a rat model of partial liver transplantation with hepatic arterialization and to investigate the postoperative histopathologic changes of the grafts. MethodsModified twocuff technique was applied to establish a rat model of partial liver transplantation, and the donor’s celiac artery was anastomosed with the recipient’s right renal artery. The biopsy of the grafts was performed on the day 1,2,4 and 7 after transplantation. Results85.4% of the recipients had survived for one week.Nuclear mitoses were seen on the postoperative day 2 by microscopy, while on the day 4 they were found occasionally. Two nucleus cells were seen on the day 4 and 7. Conclusion The stability of the model is improved by modifying the technique. Liver acupuncture biopsy is a simple, safe and feasible way to be applied in the research of postoperative problems of liver transplantation. Reconstruction of hepatic artery is possible to enhance the regeneration of liver grafts.

    Release date:2016-08-28 04:43 Export PDF Favorites Scan
  • A New Model on Isolated Human Testes with IschemiaReperfusion Injury

    Objective To establish a new model on isolated human cadaver testes with ischemiareperfusion (I/R). MethodsThirteen isolated cadaver testes contributed by 13 persons were preserved under 0℃-4℃ hypothermia and then reperfused under 37℃. Histological and histochemical changes were observed. Results4℃ cold ischemia in 12 hours induced only trivial swelling and vascular degeneration of endothelial cells (ECs), obvious pathologic changes occurred after 24 hours, including detachment of ECs, separation between basement membrane and seminiferous epithelium, degeneration and detachment of spermatogenous cell and edema of mesenchyme. Injury was worse along with the prolongation of cold preservation time. Changes of LDH and SDH activities were found by histochemical staining. Reperfusion following 6 hours ischemia induced tissue injury and unusual enzyme activity. All changes were more obvious after reperfusion following 12,18,24 or 36 hours cold ischemia.Conclusion This new model on isolated cadaver testes with ischemiareperfusion is successful, it can substitute other solid organs of human beings for I/R injury study.

    Release date:2016-08-28 05:11 Export PDF Favorites Scan
  • FACTORS INFLUENCING SURVIVAL IN PATIENT WITH GASTRIC CARCINOMA AFTER RESECTION:ANALYSIS BY Cox’S PROPORTIONAL HAZARD MODEL

    Objective To clarify the most important factors affecting the survival of patient with gastric carcinoma. Methods 428 cases of resected gastric carcinoma were studied by using univariate analyses and multivariate regression analyses. Results The most significant factors influencing survival of these patients were peritoneal dissemination, Borrmann classification, type of operation, hepatic metastasis, size of tumor, location, lymph node metastasis and age. Conclusion The factors influencing survival in patient with gastric carcinoma after resection can be correctly analyzed by cox’s proportional hazard model.

    Release date:2016-08-28 05:30 Export PDF Favorites Scan
  • THE MODIFIED FOR ORTHOTOPIC LIVER TRANSPLANTATION MODEL IN HAMSTER-TO-RAT

    Liver transplantation in hamster-to-rat is a good model for the research in xenograft, but it is difficult to be performed. In order to simplify its procedures, 38 cases of liver transplantation in hamster-to-rat were performed with several technique improvments on the basis of orthotopic liver transplantation in rats. In the light of hamster’s anatomy, three cuffs anastomosis method was used. Because of its high stability and high survival rate, the model can be used widely as the research for liver xenograft.

    Release date:2016-08-29 09:20 Export PDF Favorites Scan
  • FOUNDATION AND EVALUATION OF A ACUTE PARTIAL OBSTRUCTIVE HEPATOCHOLANGITIS MODEL IN RAT

    A acute partial obstructive hepatocholangitis model by selective ligation and injection of E coli into left hepatic bile duct was successfully founded in rat. Using parameters including mortality, mitochondrial glutamic oxalacetic transaminase and ornithine carbamoytransferase activity, pathological observation and blood culture of bacteria, we evaluated the model. The authors emphasize that this models is superior to the wole-bile-duct-challenged cholangitis model, which is characterized by liver injury.

    Release date:2016-08-29 03:26 Export PDF Favorites Scan
  • Validation of Four Different Risk Stratification Models in Predicting Early Death of Chinese Patients after Isolated Coronary Artery Bypass Grafting Surgery

    Abstract: Objectives To evaluate the accuracy of four existing risk stratification models including the Society of Thoracic Surgeons(STS) 2008 Cardiac Surgery Risk Models for Coronary Artery Bypass Grafting (CABG), the European System for Cardiac Operative Risk Evaluation (EuroSCORE), the American College of Cardiology/American Heart Association (ACC/AHA) model, and the initial Parsonnet’s score in predicting early deaths of Chinese patients after CABG procedure. Methods We collected clinical records of 1 559 consecutive patients who had undergone isolated CABG in the Fu WaiHospital from November 2006 to December 2007. There were 264 females (16.93%) and 1 295 males (83.06%) with an average age of 60.87±9.06 years. Early death was defined as death inhospital or within 30 days after CABG. Calibration was assessed by the Hosmer-Lemeshow (H-L) test, and discrimination was assessed by the receiveroperatingcharacteristic (ROC) curve. The endpoint was early death. Results Sixteen patients(1.03%) died early after the operation. STS and ACC/AHA models had a good calibration in predicting the number of early deaths for the whole group(STS: 12.06 deaths, 95% confidence interval(CI) 5.28 to 18.85; ACC/[CM(159mm]AHA:20.67deaths, 95%CI 11.82 to 29.52 ), While EuroSCORE and Parsonnet models overestimated the number of early deaths for the whole group(EuroSCORE:36.44 deaths,95%CI 24.75 to 48.14;Parsonnet:43.87 deaths,95%CI 31.07 to 56.67). For the divided groups, STS model had a good calibration of prediction(χ2=11.46, Pgt;0.1),while the other 3 models showed poor calibration(EuroSCORE:χ2=22.07,Plt;0.005;ACC/AHA:χ2=28.85,Plt;0.005;Parsonnet:χ2=26.74,Plt;0.005).All the four models showed poor discrimination with area under the ROC curve lower than 0.8. Conclusion The STS model may be a potential appropriate choice for Chinese patients undergoing isolated CABG procedure.

    Release date:2016-08-30 05:57 Export PDF Favorites Scan
  • Establishment of Acute Ischemic Left Ventricular Heart Failure Model in Sheep

    Objective To report an acute ischemic left ventricular heart failure model of safe, simple, relatively steady, and reproducible in sheep. Methods Fourteen female sheep with a body weight of 36.80±3.43kg were used in this study. Heart failure model was induced by partial occluding the middle left circumflex coronary artery (LCX) combined with pacemaker-induced tachycardia. Hemodynamic measurement was done before and after heart failure, myocardial examination was observed. Results Heart failure model was induced successfully in 10 sheep. Cardiac output dropped from 3.74±0.48L/min to 2.02±0. 51L/min (P〈0. 01), mean arterial pressure decreased from 116. 10± 14.15 mmHg(1kPa = 7.5mmHg) to 68. 10± 14. 72mmHg (P〈0.01), central venous pressure rose from 7. 10±2.18mmHg to 10. 70± 3.50 mmHg (P〈0.05), right ventricular end-diastolic pressure increased from 6.10±3.57mmHg to 9.90±4.41mmHg(P〈0.05), left atrial pressure increased from 8.10±2.13 mmHg to 12.00± 4.57mmHg (P〈0. 01 ), and left ventricular end-diastolic pressure increased from 8. 50± 4. 17mmHg to 13.10± 10. 64mmHg(P〉 0. 05). The myocardial ultrastructure injuries was marked. Conclusions Acute ischemic left ventricular heart failure could be induced by partial occlusion of the middle LCX combined with pacemaker-induced taehyeardia in sheep. This model is simple, easy to manipulate, relatively steady, and reproducible . It may be used for assessing cardiac assist devices.

    Release date:2016-08-30 06:18 Export PDF Favorites Scan
  • AN EXPERIMENTAL OSTEONECROSIS OF FEMORAL HEAD INDUCED BY A COMBINATION OF A SINGLELOW-DOSE LIPOPOLYSACCHARIDE AND METHYLPREDNISONE

    【Abstract】 Objective To investigate both incidence and mechanism attributing to steroid-associated osteonecrosisof femoral head(ONFH) using an experimental protocol with a single low-dose l i popolysaccharide (LPS) injection andsubsequently three injections of high-dose methylprednisolone (MPS). Methods Twenty-five New Zealand white rabbits with body weight of (3.0 ± 0.3) kg were divided randomly into 2 groups. In treatment group, 19 rabbits received one intravenous injection of LPS (10 μg/kg); 24 hours later, three injections of 20 mg/kg of MPS were given intramuscularly at an interval of 24 hours. Additional 6 rabbits which received normal sal ine injection at the same time point were used as controls(control group). The blood samples were collected for hematological examinations before and after LPS injection, MRI was performed on bilateral hip six weeks after last MPS injection, meanwhile, bone marrow was aspirated from femoral head region to evaluate stem cell’s activity. Bilateral femoral heads were harvested to make histopathology examination. Results All animals survived throughout the experiment period except one death on the second day after LPS injection. In the histopathological examinationfor the femoral head, ONFH+ was observed in 16 rabbits (88.9%), and the lesions were mainly in the metaphysis. In ONFH+ rabbits, micro vessels fibrous thrombosis and extravascular marrow fat cell size increasing were found around necrotic bone; The femoral heads of control group had no changes. MRI accurate ratio was 93.8% (15/16). Compared to basel ine, a significant decrease in ratio of tissue plasminogen activator/plasminogen activator inhibitor 1 and activated partial thromboplatin time, and a significant increase in ratio of low-density l ipoprotein/high-density l ipoprotein were only found in ONFH+ rabbits (P lt; 0.05). Meanwhile there was a significant decrease in the number of CFU-F (8.50 ± 9.63) compared with the control (70.17 ± 7.78, P lt; 0.05). Conclusion A single low-dose LPS injection and subsequent three injections of high-dose MPS is effective on building steroid-associated ONFH model, coagulation and l ipometabol ism abnormal ity, activity degeneration of stem cell may be the key factors of ONFH.

    Release date:2016-09-01 09:10 Export PDF Favorites Scan
  • A MODEL FOR STUDYING ON MECHANICAL RESPONSES OF OSTEOBLAST SEEDED IN THREE DIMENSIONAL SCAFFOLD

    Objective To establish a model for studying on mechanical responses of osteoblasts seeded in 3 dimensional(3D) scaffold. Methods Fifty pieces of bioderived cancellous bones, whose holes were 500 to 800 μm and density was 0.36 to 0.45g/cm3, were obtained as the scaffolds. They were cultured with the third passage suspension of Wistar rat. Twenty-four of the 50 scaffolds were constructed under apparent strain sine waveform with amplitude of 1 000 με, frequency of 3 Hz, and duration of 3 min/d, as experimental group. The other scaffolds were control group. After 3day coculture, osteoblasts were observed with scanning electron microscope. The proliferation of the osteoblasts was checked by MTT on scheduled date. Results Scanning electron microscopic observation showed that osteoblasts ttached and spread on the trabeculae, which presented the validity of the model under proper mechanical condition. Experiment showed that mechanical environment promoted theproliferation of osteoblasts. The observation of proliferation of osteoblasts showed that the quantity of osteoblasts in the experimental group was higher than that in the control group 1,4,8,12,16,20,24, and 28 days after culturing. Therewas significant difference between the two groups 12,16,20,24,and 28 days afterculturing(P<0.05). Conclusion The establishment of the model can facilitate the study of mechanical responses of osteoblasts under different conditions.

    Release date:2016-09-01 09:24 Export PDF Favorites Scan
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