According to our teaching practice, it is analyzed that the application of multimedia to malhematic teaching in the medical academy has some advantages and disadvantages. On the basis of the analysis, suggesled are some improving measures, which are as follows: studying advanced educational theories and modern educational techniques; making courseware on carefully selected teaching content; setting up a scientific and effective estimating system.

Objective To establish a simple , practical , highly-effective and stable method for the isolation and cultivation of rat hair follicle cells. Methods Under sterile condition, single hair follicle was taken out after the skin around the barbel of SD neonatal rats was sheared off. And then the hair follicles were digested with two-step method with Type Ⅰcollagenase and trypsin. The obtained cell suspension was planted into the culture plate which was covered with extracellular matrix, and then was cultivated with K-SFM culture medium containing fetal bovine serum with volume fraction of 1%. On the next day, K-SFM culture medium was replaced with serum-free culture medium. The remaining tissues were cut into pieces and spread out in the culture flask, and then were cultivated with HG-DMEM culture medium containing serum. Two kinds of cells were harvested and then were identified by immunofluorescence. The hair follicle epithelial cells were tested by flow cytometer. Results The hair follicle epithelial cells obtained through the above methods showed rapid adherence, and were round or polygon-like , with typical cobblestone-like morphology. The long spindle-shaped cells were seen around the tissues cultivated, having many protrusions on the surface of the cells, and they were interconnected into reticular structure. The expression of cytokeratin 15, cytokeratin 19 and β1 integrin in epithelial cells were positive. Most of the epithelial cells were in the G1 phase, accounting for 75.6%. The expression of laminin ( LN), fibronectin ( FN) and vimentin in the connective tissue sheath cells were also positive. Conclusion The cells harvested by modified two-step enzyme digestion method have confirmed as hair follicle cells and fibroblasts, and the obtained cells are of rapid adherence, good homogeneity, and active proliferation.

Objective To explore the feasibility of repairing skin defect with Pelnac tissue engineering skin and cultured epidermal stem cells ( ESCs) and fibroblasts. Methods ESCs and fibroblasts in SD rats were isolated and cultured in vitro, and then were detected by immunohistochemistry. Fibroblasts were seeded in Pelnac material to construct dermis, and ESCs were seeded on the surface of dermis to construct tissue engineering skin. Thirty BALC/c nude mice were randomly divided into groups A, B and C. After mouse back skin defect model was established, group A was transplanted with Pelnac material, group B was transplanted with compound of Pelnac and fibroblasts, and group C was transplanted with Pelnac tissue engineering skin. The wound healing was observed after operation. The wound tissues were sampled for pathological histology test on the 5th and 7th day after transplantation. Results The expression of cytokeratin 15 and β1 integrin in ESCs was positive, and the expression of laminin ( LN) and fibronectin ( FN) in fibroblasts was positive. In group C, the wound healing of nude mice was the best, characterized by the proliferation of fibroblasts, obvious new capillaries and regularly arranged epidermal cells at the transplantation sites. Conclusion Pelnac tissue engineering skin has good effects on promoting repair of skin defect of nude mice.

Objective To explore the conditions for the restoration of competitive dysbacteriosis with antibiotics. Methods The mathematical model of the two competitive floras was analyzed by the Qualitative Theory of Ordinary Differential Equations. Results Three different types of dysbacteriosis and their restoring conditions were obtained. Conclusion Different restoring schemes should be applied for the regulation of different types of dysbacteriosis. Misuse of antibiotics can not result in satisfactory therapeutic effect.

Based on the analysis of the management of Director 's target responsibility system in China Academy of Chinese Medical Sciences these years, the methods and experience were introduced in this paper. How to further improve the management was also discussed, providing a certain reference for the target responsibility system management of scientific research institutes.

Objective To investigate the correlation of plasma matrix metalloproteinase-3 (MMP-3)levels and MMP-3 Lys45Glu (rs679620) polyrnorphism with ischemic stroke and its TOAST subtypes.Methods The patients with large artery atherosclerotic stroke (LAA) and small artery occlusion stroke (SAO)according to TOAST etiological typing (ischemic stroke group) and healthy subjects (control group) were enrolled.The enzyme-linked immunosorbent assay was used to detect plasma MMP-3 level.The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the genotypes of MMP-3 Lys45Glu.Results A total of 233 patients with ischemic stroke were enrolled,in which 162 were LAA and 71 were SAO; 200 healthy subjects were taken as controls.The plasma MMP-3 level in the ischernic stroke group was significantly higher than that in the control goup (253.99 ± 75.02 ng/ml vs.196.38 ± 78.17 ng/ml;t =7.813,P=0.000).The plasma MMP-3 level in the LAA group (262.81 ±69.23 ng/ml) was significantly higher than those in thegroups of SAO (233.85 ± 83.90 ng/ml,P =0.008) and control (P =0.000),and the plasma MMP-3 level in the SAO was also significantly higher than that in the control group (P =0.000).Multivariate logistic regression analysis showed that the increased serum MMP-3 level was an independent risk factor for ischemic stroke (odds ratio [OR] 1.012,95％ confidence interval [CI] 1.008-1.015; P =0.000).There was no significant difference in the frequencies of genotype (x2 =2.085,P =0.353) and allele (x2 =2.29,P =0.130) of MMP-3 Lys45Glu between the ischemic stroke group and the control group.However,there were significant difference in MMP-3 Lys45Glu genotype frequencies among.the groups of LAA,SAO and control (x2 =10.39,P=0.034).The AA + GA genotype frequency in the LAA group was significant higher than those in the groups of SAO (65.4％ vs.49.3％ ;x2 =5.375,P =0.020) and control (65.4％ vs.54.0％ ;x2 =4.84,P =0.028).There was no significant difference in the allele frequencies among the groups of LAA,SAO and control (x2 =3.887,P =0.143).Multivariate logistic regression analysis showed that MMP-3 Lys45Glu polymorphism was an independent risk factor for LAA (OR 1.783,95％ CI 1.183-2.688; P =0.006).The plasma MMP-3 level in patients with the genotypes AA (n =73),GA (n =176) and GG (n =184)were 235.70 ± 70.85 ng/ml,(244.20 ± 85.90 ng/ml and 207.98 ± 77.61 ng/ml.There were significant difference in the plasma MMP-3 levels among the patients with the genotypes AA,GA and GG (F=9.682,P =0.000).The plasma MMP-3 level in the patients with the genotype AA + GA was significantly higher than that in patients with genotype GG (241.71 ± 81.73 ng/ml vs.207.98 ± 77.61 ng/ml; t =4.336,P =0.000).Conclusions The plasma MMP-3 level increased in patients with LAA or SAO,especially in the patients with LAA.The MMP-3 Lys45Glu polymorphism might be associated with the plasma MMP-3 level and LAA.

Objective To observe the variation tendency of laboratory indexes after delivery in pregnant women with acute fatty liver of pregnancy (AFLP) and the effects of plasma exchange (PE) on the patients prognoses and those parameters. Methods The data of 37 patients with AFLP admitted to the Department of Intensive Care Unit (ICU) of Anhui Provincial Hospital from January 2009 to June 2017 were retrospectively analyzed and the authors tried to clarify the natural course of AFLP; all the selected patients met the Swansea criteria of the AFLP diagnosis. The patients were divided into a PE group (9 cases) and a non-PE group (28 cases) according to whether they were treated with PE or not. At the same time, the effects of PE on liver function and coagulation parameters in the patients were analyzed. Results The most common clinical symptoms of 37 AFLP patients were as follows: nausea and vomiting (21 cases, incidence 56.8%), jaundice (21 cases, 56.8%), upper abdominal pain (14 cases, 37.8%), and more than 90% of patients had more than one symptom. All 37 patients with AFLP had abnormal liver function, their differences in the severity degrees were great, and the level of aspartate aminotransferase (AST) was (271.65±265.90) U/L;the levels of creatinine (SCr) of 72.9% patients (27 cases) were more than 140 mmol/L; the prothrombin times (PT) of 72.97% patients (27 cases) were more than 15 seconds; all patients had received blood product transfusion. Liver function and blood coagulation parameters mostly returned to normal within 1 week after delivery: AST rapidly decreased on the 1 - 2 days after delivery and then continued to decrease; all the cholesterol levels in the two groups decreased to the lowest levels within 3 - 4 days after delivery and then began to rise; the total bilirubin (TBil) levels kept on basically unchanging after delivery; in the patients with levels of platelet counts (PLT) on admission ≥ 150×109/L, on the second day after delivery, their counts returned to approximately 100×109/L, while in patients with PLT < 150×109/L on admission, on the sixth day after delivery, the counts began to slowly increase to about 100×109/L; the patients with fibrinogen (Fib) levels > 1.5 g/L on admission, the levels slightly decreased 2 days before delivery, then gradually recovered and stabilized after delivery, while the patients with Fib < 1.5 g/L, the levels began to rise slowly on the second day after delivery; prothrombin time (PT) and activated partial thromboplastin time (APTT) were basically return to the normal reference ranges on the fifth day after delivery. The PE therapy could significantly improve the patients' laboratory indexes: the levels of AST, TBil, PLT, PT were significant lower immediately and on the second day after PE compared with those levels before the PE [AST (U/L): 197 (114, 383), 116 (65, 311) vs. 239 (125, 430), TBil (μmol/L):109 (67, 126), 125 (103, 178) vs. 164 (99, 198), PLT (×109/L): 96.44±33.10, 89.89±33.03 vs. 126.22±40.83, PT (s): 17.82±5.93, 18.36±3.19 vs. 22.67±8.44, all P < 0.05]. Conclusion After terminating the delivery in time for about one week, the AFLP patients' various indexes may basically return to normal; PE therapy can improve the patients' liver function and coagulation indexes.

Organ transplantation is an effective treatment for end-stage organ failure. However, organ shortage has always been a common problem faced by countries around the world. The recognition and active participation of intensive care unit (ICU) medical staff in organ donation contributes to promoting the development of organ donation, thereby alleviating the shortage of donor organ. In this article, the key strategies of ICU donor management to promote organ donation and the key strategies of ICU medical staff management to promote organ donation were summarized, aiming to provide reference for organ donation practitioners (especially ICU medical staff) and jointly facilitate the professional development of organ donation.

Objective:To evaluate the diagnostic value of metagenomics next-generation sequencing (mNGS) in detecting pathogens in bronchoalveolar lavage fluid (BALF) for pulmonary infection in solid organ transplant patients in intensive care unit (ICU).Methods:A retrospective study was conducted, the BALF samples from 46 patients with post organ transplant pneumonia/suspected pneumonia admitted to the Department of Critical Care Medicine of the First Affiliated Hospital of University of Science and Technology of China from August 2018 to August 2021 were collected, all tested by simultaneous mNGS and conventional comprehensive microbial test (CMT), and the results of CMT were used as the reference standard to compare the differences in the diagnostic value of mNGS and CMT for pulmonary infections in solid organ transplant patients, and to analyze the diagnostic value of mNGS for mixed infections.Results:① Pneumonia pathogens: a total of 31 pathogens were detected in 35 patients, including bacteria (16 species), fungi (9 species) and viruses (6 species). Among them, 25 pathogens were detected by mNGS and CMT, and only 19 pathogens were detected by mNGS. Among the microorganisms isolated by mNGS method, the detection rates of Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae were higher [51.4%(18/35), 42.9% (15/35), 31.4% (11/35), respectively]; Candida albicans, Aspergillus and Pneumocystis carinii were the most commonly detected fungi [31.4% (11/35), 22.9% (8/35), 22.9% (8/35), respectively]; 20 patients were positive for the virus, and the most commonly detected viruses were cytomegalovirus, herpesvirus and EB virus [28.6% (10/35), 20.0% (7/35), 17.1% (6/35), respectively]. In addition, one case of Brucella was detected by mNGS.② Diagnostic efficiency: as far as bacterial detection is concerned, 20 cases of negative results were obtained by CMT detection of 35 samples included in the study, and a total of 10 cases of positive results were obtained by mNGS detection of negative samples; the percentage of mNGS positive samples was significantly higher than that of CMT positive samples [odds ratio ( OR) = 5.5, 95% confidence interval (95% CI) = 1.2-24.8, P = 0.02]. When compared with CMT, the sensitivity and specificity of mNGS were 93.3% and 50.0%, and the positive predictive value (PPV) and negative predictive value (NPV) were 58.3%, 91.1%. As far as fungal detection was concerned, there was no significant difference in the percentage of positive samples between the two methods ( OR = 1.5, 95% CI = 0.5-4.2, P = 0.60); the sensitivity and specificity of mNGS were 72.2% and 64.7%, and the PPV and NPV were 68.4%, 68.8%; CMT test of the 35 included samples produced 17 negative results, and mNGS test of the negative samples produced 6 positive results. A total of 20 patients tested positive for the virus by mNGS. In addition, 23 patients (65.7%) were diagnosed with pulmonary mixed infection. Conclusion:The use of mNGS to detect pathogens in BALF can improve the sensitivity and specificity of bacterial identification of pulmonary infection in critically ill organ transplant patients, and mNGS has obvious advantages in detecting virus and identifying mixed infections.

Objective:To explore the causes and management of reoperation for mitral regurgitation in children with congenital heart disease.Methods:Twenty-four patients required reoperation for moderate to severe mitral regurgitation after mitral valve repair. The median age was 6.7 years, ranging 7 months to 14 years; and their median weight was 18.5 kg, ranging 9.2 to 47.0 kg. Among the patients who underwent reoperation for mitral insufficiency, mitral valvuloplasty was performed in 23 cases and mitral valve replacement was performed in 1 case. Reoperation for mitral valvuloplasty was performed in 7 cases after repair for partial endocardial cushion defect, 3 cases after repair for complete endocardial cushion defect, 11 cases after mitral valvuloplasty combined with other intracardiac malformations, 3 cases after mitral valvuloplasty. Reoperation for mitral replacement was performed in 1 case after mitral valvuloplasty. Reasons for reoperation included enlargement of annulus, prolapse of valves, cleft of valves, perforation of valves, avulsion of original suture and hemolysis.Results:There was no early and later death during the follow-up. Enlarged mitral annulus in 21 cases, cleft valve in 14 cases, valve prolapse in 9 cases, valve perforation in 3 cases, relaxation of tendon chord in 1 case, shortening of tendon chord in 1 case, loss of tendon chord in 2 cases and avulsion of original suture in 3 cases were confirmed. Mitral annuloplasty, annular junction contraction, cleft closure, aberrant orifice closure, Chordae shortening or neo-chordae implantation, prosthetic ring and mitral valve replacement were performed in these cases. The mean cardiopulmonary bypass time and aorta clamp time were(129.8±69.9)min and(69.1±41.1)min. Echocardiograghy revealed slight and mild mitral regurgitation in 21 cases, moderate mitral regurgitation in 2 cases and severe mitral regurgitation in 1 case. During the follow-up for 7 to 84 months. Six months after discharge, 21 cases showed slight and mild mitral regurgitation and 3 cases had moderate mitral regurgitation.Conclusion:The main reasons for reoperation of mitral insufficiency in children are mainly due to the progress of valvular disease or inappropriate suture in the first operation. The clinical results were excellent after reoperation for mitral valve insufficiency.