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Objective:To explore the role of video-assisted feedback in clinical skill teaching in undergraduate classes and its application effect.Methods:The experimental control method was adopted in the study. A total of 185 students from Eight-year program of clinical medicine of Batch 2014 and Five-year program of clinical medicine of Batch 2016 in Tongji Medical College of Huazhong University of Science and Technology were collected as the experimental group, and another 166 students from Eight-year program of clinical medicine of Batch 2013 and Five-year program of clinical medicine of Batch 2015 as the control group. The experimental group adopted the teaching mode of video-assisted feedback and the control group received the traditional teaching mode. By the end of training sessions, the differences between the two groups in both the skill assessments and the theories were compared. A satisfaction survey about the video-assisted feedback was made in the experimental group. GraphPad Prism 5 was used for t test. Results:In the students from Five-year program of clinical medicine, the scores of theoretical assessment in the experimental group were (87.64±0.94) points and the scores of skill assessments were (84.78±0.54) points; the scores of theoretical assessment in the control group were (85.14±0.80) points and the scores of skill assessments were (83.10±0.53) points. In the students from Five-year program of clinical medicine, the difference of both the theoretical and the skill assessment scores between the experimental group and the control group was statistically significant ( P<0.05). In the students from Eight-year program of clinical medicine, the scores of theoretical assessment in the experimental group were (86.46±0.66) points and the scores of skill assessments were (86.38±0.73) points; the scores of theoretical assessment in the control group were (84.90±1.21) points and the scores of skill assessments were (83.79±0.64) points. The difference of the skill assessment scores between the experimental group and the control group was statistically significant ( P<0.05), and no significant difference was found in the theoretical assessment. The questionnaire survey in the experimental group based on video-assisted feedback teaching method showed that 93.3% (168/180) of students said that they would not take the initiative to practice after class if there was no video shooting session; 87.8% (158/180) of the students thought the video-assisted feedback teaching method improved their ability of independent learning; 82.8% (149/180) of students thought this method significantly increased their learning efficiency and confidence in clinic; 71.1% (128/180) of the students felt that after-class video shooting, their self-confidence was improved when they faced the corresponding operation clinically. Conclusion:The application of video-assisted feedback has significantly improved the outcome of clinical skill training for students, as compared to the traditional teaching mode.
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Objective:To explore the effect of estrogen-related receptor α (ERRα) on lipopolysaccharide (LPS)-induced vascular endothelial cell apoptosis and tight junction protein degradation.Methods:RPMVECs transfected with shERRα were cultured in vitro and divided into four groups: Normal control group (Ctr group); shERRα knockdown group (shERRα group); normal cells + LPS treated group (LPS group): The cells in the six-well plates were cultured in serum-free medium for 12 h, and then treated with 20 μg/mL LPS for 12 h; and shERRα+LPS group: ERRα knockdown cells were treated as the LPS group. ROS fluorescence kit was used to detect the intracellular ROS levels . Apoptosis ratio was detected by TUNEL staining, AnnexinV-FITC and PI. Cell membrane ZO-1 expression was detected by cellular immunofluorescence, and the levels of apoptosis-related proteins Bcl-2, Bax, Smac, Cytochrome c, and tight junction protein ZO-1, as well as the expression of Occludin, JAM-A and E-Ca at molecular level were detected by Western blot.Results:Compared with the Ctr group and the shERRα group, the ROS level, apoptosis rate (TUNEL test: 16.44 ± 2.55; and flow cytometry test: 23.56 ± 2.22), the expression of pro-apoptotic proteins Bax, Smac and Cytochrome c were increased in the LPS group, while the expression of anti-apoptotic proteins Bcl-2 and tight junction protein were decreased. In the LPS group. Cellular immunofluorescence results showed that the ZO-1 was degraded in the cell membrane and the network structure was broken. Compared with the LPS group, inhibition of ERRα in the shERRα+LPS group increased cell damage.Conclusions:ERRα can negatively regulate the apoptosis and affect the function of pulmonary microvascular endothelial cells, thereby regulating sepsis-induced acute lung injury.
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Objective To investigate the effect of estrogen-related receptor alpha(ERRα)on lipopolysaccharide-induced inflammatory response in rat pulmonary microvascular endothelial cells (PMVECs) and its mechanism.Methods PMVECs were cultured in vitro.When the cells were in the logarithmic growth phase,the cell were ransfected with lentivirus,and a stable low-expression ERRα cell line was constructed.The cells were divided into four groups:Ctr group (normal control group),Ctr+LPS group (normal celI+LPS treatment group),shERRα1 (shERRα1 gene knockdown group),and shERRα1+LPS group (shERRα1 gene knockdown +LPS treatment group).After 20 μg/mL LPS stimulated cells in the control group and shERRal group for 6,12 and 24 h,cell counting kit-8 (cck-8) was used to detect the cell proliferation ability of each group,and enzyme-linked immunosorbent assay (ELISA) was used to detect the concentrations of tumor necrosis factor alpha (TNF-α) and Interleukin-1β (IL-1β) in cell culture fluid.After 12 h LPS stimulation,the expression levels of ERRα and NF-κB related proteins (p-p65,p65,P-IKBα,IKBα) were measured by Western blot.Pairwise comparisons were performed with SNK-q test (two-tailed),and multiple-group comparisons were performed with one-way ANOVA.The non-parametric test of rank transformation was used when homogeneity of variance were not met.P value＜0.05 was considered significantly different.Results Compared with the control group,ERRα expression in the shERRα group was significantly decreased (0.09±0.01 vs 0.15±0.01).At 6,12 and 24 h after LPS stimulation,compared with the control group,the cell proliferation ability (％) of the shERRαl+LPS group was significantly reduced (99.68±4.53 vs 48.62±1.60) and the concentration of TNF-α (ng/mL) (15.76±3.38 vs 5 498.91±367.95) and IL-1β (ng/mL) (14.41±3.86 vs 6 014.92±277.33) in the cell culture supematant were significantly increased.The change was most obvious after 12 h stimulation.Meanwhile the expression of p-p65 (0.30±0.50 vs 1.05±0.07) and p-IKBα (0.27±0.04 vs 0.77±0.06) were increased significantly,while the expression of IKBα (0.96±0.07 vs 0.14±0.04) was decreased significantly in the shERRαl+LPS group (all P＜0.05).Conclusion ERRα gene attenuates LPS-induced inflammatory response in rat pulmonary microvascular endothelial cells by inhibiting NF-κB signaling pathway activation.
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Adrenal rest tumor (ART) is a well-known complication in congenital adrenal hyperplasia (CAH), which may occur in all age groups, especially in adolescence and adulthood. Tumors that occur in the testicular known as testicularadrenal rest tumor (TART), in the ovarian and parovarian tissue known as ovarian adrenal rest tumor (OART). ART is one of the major causes of reproductive dysfunction in adult with CAH. Early prevention and treatment is the key to avoid irreversible damage to gonadal function. In the past, we paid more attention to TART in children, while ignored TART and OART in adults. This article will review the origin of tumor cells, pathogenesis, epidemiology, diagnosis, treatment and prognosis of CAH associated with ART, which aims to guide clinical work through the profound understanding of CAH with ART.
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Objective To investigate influences of estrogen-related receptor α(ERRα) on pulmonary vascular endothelium of rats undergoing sepsis. Methods Male Sprague-Dawley (SD) rats were divided into four groups according to the random number table method (12 in each group): normal control group (NC group), sham operation group (Sham group), sepsis model caused by cecal ligation and puncture (CLP) group (CLP group), XCT790 intervention group (XCT790 group, given the XCT790 2.5 mg/kg via intraperitoneal injection 30 minutes before CLP). After 24 hours, rats were sacrificed and the organs were harvested. The pathological changes of lung tissue were observed using hematoxylin and eosin (HE) staining, and the ultrastructural changes of lung tissue were observed by double staining of uranium citrate with lead acetate, the degree of apoptosis of pulmonary capillary endothelial cells were observed by TdT-mediated dUTP nike end labeling stain (TUNEL), the permeability of lung vascular endothelial was detected by Evans blue (EB) staining, the levels of serum cytokines were detected by enzyme linked immunosorbent assay (ELISA), and white blood cell count in bronchial alveolar lavage fluid (BALF) was detected. Results Compared with NC group and Sham group, the CLP group and XCT790 group had severe pathological damage and increased lung tissue permeability, the levels of serum cytokines and white blood cell count in BALF were increased. Compared with CLP group, the pathological changes of lung tissue, the degree of ultrastructural damage of lung tissue, the degree of apoptosis of lung capillary endothelial cells in XCT790 group further intensified, the permeability of lung endothelial barrier further increased [the content of EB (μg/g): 116.00±15.46 vs. 60.19±19.79, P < 0.05], and the level of serum cytokines further increased [interleukin-1β(IL-1β, ng/L): 71.38±4.01 vs. 56.58±2.45, interleukin-6 (IL-6, ng/L): 741.62±88.94 vs. 534.22±72.70, tumor necrosis factor-α(TNF-α, ng/L):188.55±7.41 vs. 143.33±11.27, all P < 0.05], the white blood cell count in the BALF increased further (×104/L:193.79±27.46 vs. 99.34±36.41, P < 0.05). Conclusion ERRα can aggravate inflammation in sepsis rats, destroy lung tissue and increase pulmonary permeability.
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Adrenal rest tumor ( ART ) is a well-known complication in congenital adrenal hyperplasia (CAH),which may occur in all age groups, especially in adolescence and adulthood. Tumors that occur in the testicular known as testicularadrenal rest tumor ( TART ) , in the ovarian and parovarian tissue known as ovarian adrenal rest tumor ( OART) . ART is one of the major causes of reproductive dysfunction in adult with CAH. Early prevention and treatment is the key to avoid irreversible damage to gonadal function. In the past, we paid more attention to TART in children, while ignored TART and OART in adults. This article will review the origin of tumor cells, pathogenesis, epidemiology, diagnosis, treatment and prognosis of CAH associated with ART, which aims to guide clinical work through the profound understanding of CAH with ART.
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Bone marrow adipose tissue (MAT) is formed by the accumulation of adipocytes in the bone marrow cavity. Previously, the function of MAT is mainly considered to be filled with bone marrow cavity for the mechanical support. However,with the in-depth study of MAT,it has been gradually understood that MAT is not only a part of the bone marrow microenvironment,may also be a new endocrine "organ". The main component of bone marrow adipocytes(BMA) plays a regulatory role in bone marrow and systemic metabolism through the autocrine and paracrine secretion of adiponectin, leptin, interleukin-6, and a series of cytokines. Though its biological characteristics are somewhat similar with white fat adipose tissue(WAT) and brown adipose tissue(BAT),there are some significant differences,so MAT is thought to be a special adipose tissue. MAT is also involved in the development of hematological diseases,metabolic diseases,degenerative diseases,and may affect their outcomes. MAT may be the auxiliary diagnostic criteria and treatment targets of such diseases. This article will review the MAT's own biological characteristics,the differences and associations among three types of adipose tissue and the link between MAT and the diseases,which aims to explore the new research direction through the profound understanding of MAT.
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Objective To investigate the effects of multidrug resistance-associated protein 4 (MRP4) on the cytoskeleton and cellular permeability of rat pulmonary microvascular endothelial cells (PMVECs) induced by lipopolysaccharide (LPS).Methods PMVECs were cultured for 3 to 6 generations were randomly divided into 4 groups:control group,LPS group,Ad-shMRP4 group (adenoviral expression of a short-hairpin RNA directed against MRP4),Ad-shRNA group.The infection rate of cells was detected by fluorescence microscope observation.The level of MRP4 was assayed by Western botting.Monolayer permeability was determined by the Transwell assay.The morphological characteristic and distribution of Factin was measured by laser confocal fluorescence microscope.Results Compared with control group,the expression of MRP4 protein was up-regulated (P ＜ 0.05) and the significant increase in the permeability of endothelial cells (2 h,6 h,12 h and 24 h respectively:0.28 ±0.02 vs.0.41 ±0.04,0.32 ±0.02,0.30 ±0.01 vs.0.53±0.04,0.39±0.03,0.33 ±0.04 vs.1.12±0.17,0.70 ±0.07,0.32±0.03 vs.0.79 ± 0.02,0.57 ± 0.05,P ＜ 0.05),the F-actin was remodeled,and the stress fibers were formed in LPS group and Ad-shMRP4 group.However,compared with LPS group,the expression of MRP4 protein was down-regulated (P ＜ 0.05) and the markedly decrease in the permeability of endothelial ceils (2 h,6 h,12 h and 24 h respectively:0.41 ± 0.04 vs.0.32 ± 0.02,0.53 ± 0.04 vs.0.39 ± 0.03,1.12 ± 0.17 vs.0.70 ± 0.07,0.79 ± 0.02 vs.0.57 ± 0.05,P ＜ 0.05) was found,and the remodeling of F-actin,and the formation of stress fibers were observed in Ad-shMRP4 group.Conclusions Silencing of MRP4 gene can effectively attenuates LPS-induced increase in the endothelial cell permeability and the destruction of cytoskeleton,thus playing an important role in the protection of endothelial cell barrier.
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Objective To investigate the effects of multidrug resistance-associated protein 4 (MRP4) on the cytoskeleton and cellular permeability of rat pulmonary microvascular endothelial cells (PMVECs) induced by lipopolysaccharide (LPS).Methods PMVECs were cultured for 3 to 6 generations were randomly divided into 4 groups:control group,LPS group,Ad-shMRP4 group (adenoviral expression of a short-hairpin RNA directed against MRP4),Ad-shRNA group.The infection rate of cells was detected by fluorescence microscope observation.The level of MRP4 was assayed by Western botting.Monolayer permeability was determined by the Transwell assay.The morphological characteristic and distribution of Factin was measured by laser confocal fluorescence microscope.Results Compared with control group,the expression of MRP4 protein was up-regulated (P ＜ 0.05) and the significant increase in the permeability of endothelial cells (2 h,6 h,12 h and 24 h respectively:0.28 ±0.02 vs.0.41 ±0.04,0.32 ±0.02,0.30 ±0.01 vs.0.53±0.04,0.39±0.03,0.33 ±0.04 vs.1.12±0.17,0.70 ±0.07,0.32±0.03 vs.0.79 ± 0.02,0.57 ± 0.05,P ＜ 0.05),the F-actin was remodeled,and the stress fibers were formed in LPS group and Ad-shMRP4 group.However,compared with LPS group,the expression of MRP4 protein was down-regulated (P ＜ 0.05) and the markedly decrease in the permeability of endothelial ceils (2 h,6 h,12 h and 24 h respectively:0.41 ± 0.04 vs.0.32 ± 0.02,0.53 ± 0.04 vs.0.39 ± 0.03,1.12 ± 0.17 vs.0.70 ± 0.07,0.79 ± 0.02 vs.0.57 ± 0.05,P ＜ 0.05) was found,and the remodeling of F-actin,and the formation of stress fibers were observed in Ad-shMRP4 group.Conclusions Silencing of MRP4 gene can effectively attenuates LPS-induced increase in the endothelial cell permeability and the destruction of cytoskeleton,thus playing an important role in the protection of endothelial cell barrier.
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Objective To introduce a new modified percutaneous dilational tracheostomy and compare the application effect of percutaneous dilational tracheostomy with modified percutaneous dilational tracheostomy in the treatment of critically ill patients. Methods A total of 60 critically ill patients undergoing tracheotomy were selected , and they were randomly divided into two groups according to the methods of tracheotomy. Sex, age, weight, body mass index, acute physiology and chronic health evaluation, operation time, incision size, intraoperative blood loss, incision healing time, incidences of complications after operation were compared between the two groups. Results There were not statistically significant differences of in sex, age, weight, body mass index, and acute physiology and chronic health evaluation between percutaneous dilational tracheostomy group and modified percutaneous dilational tracheostomy group (P>0.05). Operation time, incision size and intraoperative blood loss of modified percutaneous dilational tracheostomy group was statistically significantly shorter than that of percutaneous dilational tracheostomy group [(5.80 ± 1.19) min vs. (7.65 ± 1.05) min, (8.33 ± 3.30) ml vs. (11.33 ± 4.34) ml, (1.08 ± 2.96) cm vs. (1.27 ± 2.54) cm] (P0.05). Conclusions The modified percutaneous dilational tracheostomy can save operation time, and reduce intraoperative blood loss, so it can be widely used.
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Objective To investigate the effect of multidrug resistance protein 4 (MRP4) overexpression on lipopolysaccharide (LPS)-induced vascular endothelial hyperpermeability of rat pulmonary micro-vascular endothelial cells (PMVECs) and its molecule mechanism. Methods Three to six passages of PMVECs were cultured in vitro, and they were divided into three groups: the cells in LPS group were only challenged by LPS 10 μg/mL after being cultured in serum-free medium for 24 hours; the cells in Ad-shRNA and Ad-MRP4 groups were infected with the empty virus control or recombinant adenovirus expressing MRP4 for 2 hours, and then were cultured in serum-free medium for 24 hours followed by stimulation of LPS 10 μg/mL. Endothelial permeability was assayed by the Transwell chamber models at 2, 6, 12, and 24 hours after LPS stimulation. Intracellular cyclic adenosine monophosphate (cAMP) levels were detected by enzyme-linked immunosorbent assay (ELISA). The morphological characteristics and distribution of F-actin was determined by laser confocal fluorescence microscope. The protein expressions of MRP4,β-catenin, vascular endothelium-cadherin (VE-cad) and ZO-1 were measured by Western Blot. Results ① After LPS stimulation, endothelium permeability and intracellular cAMP levels in PMVECs were significantly increased, peaked at 12 hours, and then decreased after 24 hours. Compared with LPS group and Ad-shRNA group, PMVECs of Ad-MRP4 group were exhibited a significant increase in endothelial permeability [12-hour permeability (A value):1.88±0.06 vs. 1.12±0.17, 1.10±0.18] and a significant decrease in intracellular cAMP level [12-hour cAMP (μg/L):2.39±0.02 vs. 2.97±0.01, 3.00±0.02, all P 0.05).② Under laser confocal fluorescence microscope, after LPS stimulation, the stress fiber formation was induced in three groups. But there were pronounced irregular aggregation of fiber in PMVECs of Ad-MRP4 group. ③ Furthermore, compared with LPS group and Ad-shRNA group, protein expression of MRP4 in Ad-MRP4 group was dramatically increased (gray value: 0.76±0.03 vs. 0.44±0.02, 0.43±0.02, both P 0.05). Conclusion MRP4 overexpression can decrease intracellular cAMP levels, reduce intercellular junction protein expression, and then exaggerate LPS-induced vascular endothelial hyperpermeability.
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Objective To investigate the protective effect of multidrug resistant associated protein 4 (MRP4) inhibitor on rats with sepsis-induced acute lung injury (ALI). Methods Sixty Sprague-Dawley (SD) rats were randomly divided into sham group, sepsis group and MRP4 inhibitor MK571 treatment group, with 20 rats in each group. Sepsis model was reproduced by cecal ligation and puncture operation (CLP), and the rats in sham group were only received celiotomy without ligation and puncture. Rats in MK571 treatment group were intraperitoneally injected with MRP4 inhibitor MK571 (20 mg/kg) 30 minutes before model reproduction, while rates in sham group and sepsis group were given the same amount of normal saline. Twenty-four hours later, the femoral artery blood of mice was collected, and arterial blood gas analysis was measured. Serum tumor necrosis-α (TNF-α) was determined by enzyme-linked immunosorbent assay (ELISA). The lung tissues were collected, and the wet/dry weight ratio (W/D) was calculated. The expression of MRP4 protein in lung tissue was determined by Western Blot. Results Compared with sham group, arterial blood pH value and arterial partial pressure of oxygen (PaO2) were significantly lowered [pH value: 7.18±0.03 vs. 7.40±0.03; PaO2 (mmHg, 1 mmHg = 0.133 kPa): 63.15±6.24 vs. 98.05±2.58], while arterial partial pressure of carbon dioxide (PaCO2) was dramatically higher in the sepsis group (mmHg: 56.60±8.30 vs. 37.85±3.18), serum TNF-α level in the sepsis group was significantly increased (ng/L: 146.24±19.99 vs. 25.77±9.83), the W/D ratio of lung tissue was significantly increased (7.75±0.47 vs. 4.09±0.58), and the expression of MRP4 protein was up-regulated in the sepsis group (gray value: 0.153±0.006 vs. 0.087±0.005, all P < 0.05). Compared with the sepsis group, arterial blood pH value (7.30±0.02 vs. 7.18±0.03) and PaO2 (mmHg: 80.30±5.34 vs. 63.15±6.24) were significantly elevated in the MK571 treatment group, while PaCO2 was dramatically decreased (mmHg: 29.25±3.24 vs. 56.60±8.30), the serum level of TNF-α was significantly decreased (ng/L: 97.96±16.72 vs. 146.24±19.99), the W/D ratio of lung tissue was significantly reduced (5.89±0.51 vs. 7.75±0.47), and MRP4 protein expression was significantly down-regulated (gray value: 0.124±0.006 vs. 0.153±0.006, all P < 0.05). Conclusion MRP4 inhibitor may improve lung function in rats with sepsis-induced ALI by down-regulating MRP4 protein expression and reducing levels of inflammatory cytokines, which exerts protective effect on ALI.
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Objective To explore the effects of multidrug resistance-associated protein 4 (MRP4) inhibition on pulmonary vascular endothelial barrier dysfunction in septic rats.Methods Sixty Sprague Dawley rats were randomly (random number) divided into three groups:sham-operated group,sepsis group,and sepsis plus MRP4 inhibitor treatment group,with 20 rats in each group.Sepsis was induced by cecal ligation and puncture.MRP4 inhibitor MK571 (20 mg/kg) was administrated by intraperitoneal injection 30 minutes before induction of sepsis.Twenty-four later,serum interlukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) levels were measured by enzyme-linked immunosorbent assay.Lung injury was assessed by histopathological examination.Lung vascular permeability was evaluated by quantitation of Evans blue dye extravasation from vascular space to lung parenchyma.Results Compared with sham group,serum IL-6 and TNF-α levels were significantly higher in sepsis group.In addition,lung injury and lung vascular permeability were elevated in sepsis group compared to sham group.Importantly,MRP4 inhibitor treatment significantly decreased serum IL-6 and TNF-α levels,improved lung injury and reduced lung vascular permeability in septic rats.Conclusions Inhibition of MRP4 protects against pulmonary vascular endothelial barrier dysfunction in septic rats.
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Objective By investigating the actualities of career development potential of eight-year program medical students, to explore a direction of training mode innovation aiming to improve career development potential. Methods Eight-year program medical graduates, their tutors, and di-rectors of their clinical department in a university hospital were the subjects of the current study. Questionnaire method was applied to evaluate professional competence including clinical skills, re-search capabilities and integrative ability . Anonymous questionnaires were dispensed to eight-year program medical graduates for self-evaluation. Distinct anonymous questionnaires were dispensed to tutors directors for evaluation. Traditional doctoral graduates (professional degree or academic degree) were set as standard for comparison of specific ability of eight-year program medical students. Results 74 out of 85 (87%) questionnaires for Eight-year program medical graduates were available. 53 out of 63 (84%) questionnaires for tutors were available. 21 out of 26 (81%) questionnaires for directors of clinical departments were available. In clinical capabilities, according to 43 percent (32 persons) of the eight-year MD graduates' self-assessment and the evaluation of 94%(50 persons) mentors and 81%(17 people) department directors, eight-year program medical graduates were regarded as lower-skilled clinicians compared with doctoral graduates with professional degree . Eight-year program medical graduates were also considered with worse research capabilities than doctoral graduates with profes-sional degree by themselves (76%, n=56), their tutors (91%, n=48), and their department directors (86%, n=18). Conclusions The survey shows that to some extent, the current eight-year clinical doctoral graduates lack of career development potential, reflecting the current training mode cannot lead to the given training goals. We suggest that both clinical skills and research capabilities should be enhanced to make sure that eight-year program medical graduates deserve the title of academic physicianorphysician scientists.
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Objective To compare the myocardial damage in patients with severe valvular heart disease undergoing open heart surgery under propofol and sevoflurane combined anesthesia.Methods Thirty-two patients with severe heart valvular disease undergoing open heart surgery were randomized into 3 groups:midazolam group (group M,n =8),propofol group (group P,n =12) and sevoflurane group (group S,n =12).Midazolam 1-5 mg,vecuronium 0.15 mg/kg and fentanyl 10-20 μg/kg were injected intravenously in group M.Propofol 1-2 mg/kg,vecuronium 0.15 mg/kg and fentanyl 10 μg/kg were injected intravenously in group P.In group S,the patients inhaled sevoflurane until the eyelash reflex disappeared,the end-tidal concentration of sevoflurane was 0.5 ％-2.0％,and vecuronium 0.15 mg/kg and fentanyl 10μg/kg were injected intravenously.The patients were mechanically ventilated after tracheal intubation.Anesthesia was maintained with iv infusion of midazolam 0.1 mg· kg-1 · h-1,fentanyl 0.2 μg· kg-1 · min-1,and vecuronium 0.12 mg· kg-1 · h-1 in group M,with iv infusion of propofol 150 μg· kg-1 · min-1 and fentanyl μg· kg-1 · min-1 in group P,or with inhalation of 0.5％-2.0％sevoflurane in group S.CPB was established routinely.The concentration of sevoflurane was 0.5 ％-1.0％ during CPB.Venous blood samples were collected before anesthesia (T1),at 20 min and 2 h after aortic unclamping (T2,3),and at 24 h after operation (T4) for determination of the levels of plasma lactic dehydrogenase (LDH),creatine kinase (CK),creatine kinase MB (CK-MB),cardiac troponin Ⅰ (cTnⅠ),superoxide dismutase (SOD)and tumor necrosis factor (TNF)-α.Myocardial tissues were taken at T2 for determination of heme oxygenase-1 (HO-1) expression and for examination of the myocardial ultrastructure.Results Compared with group M,the levels of plasma LDH,CK-MB,and CK were significantly decreased at T2-4,the levels of plasma SOD and cTnⅠ were significantly increased at T2,3,and the expression of HO-1 was up-regulated at T2 in groups P and S,and the levels of plasma TNF-α were significantly decreased at T2-4 in group P and at T2,3 in group S (P ＜ 0.05).The pathologic changes induced by I/R were less severe in groups P and S than in group M.Conclusion Both propofol and sevoflurane can attenuate the myocardial damage in patients with severe valvular heart disease undergoing open heart surgery and the effects are comparable.
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Objective To investigate the effect of ovariectomy and estrogen on secretion function and number of pancreatic islet beta cell in low-dose streptozotocin-induced diabetic rats. Methods Thirty female SD rats were randomly divided into five groups: normal control(NC) group, streptozotocin(STZ) group, ovariectomized(OVX) group, OVX + STZ(OS) group and OVX+STZ+estradiol(OSE) group. OVX, OS and OSE groups underwent ovariectomy, while NC and STZ groups underwent just sham operation. After surgery, OSE group was treated subcutaneously with estradiol 0.2 mg/kg twice weekly. At the end of 3 weeks, STZ, OS and OSE groups were induced by a single intraperitoneal injection of 40 mg/kg STZ. Then eight days later, plasma glucose and insulin levels were tested. The insulin protein, the average beta cell area and the relative beta cell mass were tested by streptavidin peroxidase conjugation method (SP). The quantification of beta cell apoptosis was performed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). The expressions of proliferating cell nuclear antigen(PCNA) protein, Bax and Bcl-2 were tested. Results With the administration of low-dose STZ, the plasma glucose was significantly higher and the insulin secretion curve after glucose loading, △I30/△G30 and modified beta cell function index(MBCI) were lower in OVX group than in other groups(all P<0.05). At the same time, the insulin protein, the relative beta cell mass and the beta cell area were dramatically decreased(all P<0.05). The beta cell apoptotic index was increased (t = 2.957, P< 0.05), the expression ratio of Bcl-2/Bax was decreased (0.41±0.03 vs. 0.76±0.05, P<0.05). Estrogen replacement therapy could obviously inhibit these changes. Compared with OS group, glucose disturbances and insulin secretion were improved dramatically in OSE group(all P<0.05); the insulin content, the relative beta cell mass and the average beta cell area were all enhanced (all P<0.05); the beta cell apoptotic rate was decreased(t =2.482, P<0.05), and the expression tatio of Bcl-2/Bax was increased (0.71±0.05 vs. 0.41±0.03, P<0.05). Conclusions The ovx rats are significantly more susceptible to low-dose STZ toxicity than in control rats. Under the effect of STZ, the ability of insulin secretion of beta cell is obviously decreased, while apoptosis is increased, which induces a higher glucose level and a lower insulin secretion. Administration of estrogen may protect OVX rats from the metabolic disturbances.
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17β-estradiol(E2), progesterone (P) and testosterone (T) were investigated for their effects on the proliferation and differentiation of primary rat calvarial osteoblasts in vitro. Rat calvarial osteoblasts were cultured with l0-10 mol/L E2, 10-9-10-6 mol/L P and l0-10 mol/L T for 20days. Cell proliferation was determined by 3H-thymidine incorporation and cell counting. Cell differentiation was examined by measuring alkaline phosphatase (ALP) activity, osteocalcin gene expression and production, bone nodule formation in different periods of culture. Our results showed that no effect of three sex hormones was observed on cell proliferation, but, the responses of cell differentiation to the hormones were more or less different. Among these three hormones used in this study, P appeared to have multi-stimulating effect on cell differentiation. Effect of T seemed not so significant as that of P on cell differentiation. Although ALP activity and osteocalcin production were increased significantly by T, it had slight effect on osteocalcin mRNA and bone nodule formation. Besides, E2 did not demonstrate any effect on cell differentiation. It is concluded that the proliferation of rat calvarial osteoblasts was independent of the presence of sex hormones. However, the differentiation of these cells were stimulated in different levels and to different extent either by P or T. P appeared to be a multi-stimulator on differentiation of such cells.
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17β-estradiol(E2), progesterone (P) and testosterone (T) were investigated for their effects on the proliferation and differentiation of primary rat calvarial osteoblasts in vitro. Rat calvarial osteoblasts were cultured with l0-10 mol/L E2, 10-9-10-6 mol/L P and l0-10 mol/L T for 20days. Cell proliferation was determined by 3H-thymidine incorporation and cell counting. Cell differentiation was examined by measuring alkaline phosphatase (ALP) activity, osteocalcin gene expression and production, bone nodule formation in different periods of culture. Our results showed that no effect of three sex hormones was observed on cell proliferation, but, the responses of cell differentiation to the hormones were more or less different. Among these three hormones used in this study, P appeared to have multi-stimulating effect on cell differentiation. Effect of T seemed not so significant as that of P on cell differentiation. Although ALP activity and osteocalcin production were increased significantly by T, it had slight effect on osteocalcin mRNA and bone nodule formation. Besides, E2 did not demonstrate any effect on cell differentiation. It is concluded that the proliferation of rat calvarial osteoblasts was independent of the presence of sex hormones. However, the differentiation of these cells were stimulated in different levels and to different extent either by P or T. P appeared to be a multi-stimulator on differentiation of such cells.