Objective To set up the experimemtal model with superior segmentalbone defect in acetabulum and implant the three-fin acetabular component, and examine the Von Mises stresses of pelvis bone with simulating single leg position in vitro using rosette strain gages method(RSGD). Methods Four kinds of three-fin components were made based on measurement of diameter, depth and roof thickness of acetabular specimens. These kinds of threefin acetabular components based on spreaded degrees of lateral fins(0,36,45 and 60°). The superiorsegmental bone defect of acetabulum in 4 cadaver pelvis specimens was made,then simulated the actual position to place implant into acetabular bone.A blank control group was set up.After being fit up the 7 sets of rosette strain gages,then specimen to test the pelvic Von Mises stresses simulating the static load of single leg on the mechanic machine.Progressive load was graded into 150, 300,450, 600, 750 and 900 N.We obtained the strains informations about loaded andun-loaded pelvis bone. Results Based on computed the strains informations,we were informed the Von Mises stresses about pelvis bone.The maximal Von Mises stresses of selected local position was 6.93 MPa and the minimal Von Mises stresses of selected local position was 1.08 MPa. Conclusion Providing the data about the mainpart of threefin acetabular component to optimize spreaded degrees of lateral fins.
【摘要】 目的 观察长期大量酒精摄入对大鼠心肌结构及心肌组织中丙二醛(MDA)、超氧化物歧化酶(SOD)和金属硫蛋白(MT)含量的影响,探讨氧化应激在酒精性心肌病大鼠中的作用。 方法 雄性健康SD大鼠45只,随机分为2组,即对照组20只和模型组25只。模型组酒精浓度从5%、10%、20%和30%依次各自由饮1周,然后递增至36%后以该浓度维持饲喂。对照组每日饮用与模型组酒精同等热量的葡萄糖水。6个月后,观察大鼠心肌组织的形态学改变及超微结构的变化,测定心肌组织中MDA、SOD及MT的含量。结果 模型组大鼠心肌细胞排列紊乱、间质充血、炎细胞浸润、线粒体肿胀、空泡形成、肌丝溶解、核膜不规则和核仁裂解。心肌组织中MDA含量明显升高(Plt;0.01),SOD活力含量明显降低(Plt;0.01),MT含量明显降低(Plt;0.01)。 结论 长期摄入大量酒精可使氧自由基代谢失衡,导致心肌损伤。氧化应激在酒精性心肌病发病机制中发挥着重要的作用。【Abstract】 Objective To observe the effect of longterm and large quantities of alcohol intake on myocardial structure of rats and the content of malondialdehyde (MDA), superoxide dismutase (SOD) and metallothionein (MT) in myocardium tissue. To study the effect of oxidative stress on the rats with alcoholic cardiomyopathy. Methods Fortyfive male and healthy SD rats were randomly divided into the control group (20 rats) and model group (25 rats).The alcoholic concentrate in model group was increased from 5%,10%,20% to 30% every week, and maintain free drinking mass concentration of 36% alcohol. The control group drink the same calories of glucose water. Six months later, the myocardial tissues were observed both in light microscope and electron microscope .The level of MDA、SOD and MT were tested in myocardium tissue. Results In the model rats, the cells of myocardial disarray, interstitial congestion, inflammatory cell infiltration, mitochondrial swelling, vacuole formation, melt filaments, irregular nuclear membrane and nucleolus cracking. The content of MDA incresed(Plt;0.01)and the activities of SOD decreased(Plt;001),levels of MT decreased (Plt;0.01) in the cardiac muscular tissues in the model group compared with the control group. Conclusion Longterm intake of large amounts of alcohol can break the balance of oxygen free radicals, which leading to the damage of myocardial. Oxidative stress plays an important role in the etiopathogenesis of alcoholic cardiomyopathy.
Objective To investigate the correlation between stress hyperglycemia ratio (SHR) and acute ischemic stroke (AIS) 1-year prognosis, to provide more clinical basis to improve the prognosis of AIS patients and to target and control the influencing factors. MethodsThe patients with AIS diagnosed for the first time and received treatment at the Shijiazhuang Fifth Hospital between May 2019 and January 2022 were retrospectively and continuously included. According to the Modified Rankin Scale score 1-year after the onset of the disease, the patients were divided into a good prognosis group and a poor prognosis group. Also the patients were divided into 2 groups based on the median of SHR. The correlation between SHR and stress blood glucose was analyzed, and the factors affecting the prognosis of AIS patients were identified. The predictive value of SHR and stress blood glucose on the prognosis of AIS patients was compared using receiver operating characteristic. Results A total of 206 patients were included. Among them, there were 125 cases (60.7%) in the good prognosis group and 81 cases (39.3%) in the poor prognosis group. The median SHR (lower quartile, upper quartile) is 1.20 (1.08, 1.33). There were statistically significant differences between the two groups in the scores of the National Institutes of Health Stroke Scale, diabetes history, hypertension history, low-density lipoprotein cholesterol, stress blood glucose, age, SHR and SHR classification (P<0.05). There was no statistically significant difference in the other indicators compared between the two groups (P＞0.05). Stress blood glucose was positively correlated with SHR (7.95±1.78 vs. 1.21±0.19; r=0.294, P<0.001). Multivariate logistic analysis showed that stress blood glucose and SHR were independent factors influencing the 1-year prognosis of AIS patients (P<0.05), and the interaction between SHR and diabetes was not significant (P>0.05) After adjusting for confounding factors, the area under the receiver operating characteristic curve of SHR for the prognosis of AIS patients was higher than that of stress blood glucose [0.682 (0.614, 0.745) vs .0.585 (0.515, 0.653); Z=2.042, P=0.041]. Conclusions SHR and stress blood glucose are independent risk factors for 1-year prognosis in AIS patients. However, SHR has a better predictive value for 1-year prognosis in AIS patients than stress blood glucose. Whether the patient has diabetes or not, the impact of SHR on the prognosis of AIS patients is consistent.
Objective To investigate the relationship among rats′ stress ulcer and gastric acid, prostaglandin (PGs) and adrenocorticotropin (ACTH) and to probe the pathogenesis, prophylaxis and therapy. Methods Rats′ stress ulcer model was made by cold water soaking and was properly treated with drugs such as hyoscine, dexamethasone, ranitidine and losec. The amount and pH of gastric juice, change of gastric mucosa and PGs and ACTH of blood were determined. Results After rats were fasted for 24 hours a little gastric juice was aspirated. After cold water soaking of rats gastric juice was increased with the pH decreased, there was gastric mucosal bleeding, blood PGs was decreased and ACTH was increased. These suggest that on stress gastric mucosa bleeding is related with decreased gastric juice pH, decreased PGs and increase ACTH.Conclusion To control stress ulcer, pH of gastric juice and amount of PGs should be increased. Losec can increase gastric juice pH, so losec is the first choice to control stress ulcer.
Objective To review the research progress of stress fracture of the lumbar pedicle. Methods The literature about the stress fracture of the lumbar pedicle was reviewed extensively and summarized. Results There are two types of stress fracture: fatigue and structure insufficient. Stress fracture of lumbar pedicle occurred mainly in the crowd with repetitive and large activities of spine, contralateral spondylolysis, or previous surgery of lumbar vertebra. The main stresses causing stress fracture of the lumbar pedicle are shear stress and twisting stress, followed by sudden hyperflexion or hyperextension of the spine. Stress fracture of lumbar pedicle was easily missed by conventional X-ray examination, usually XCT, MRI, or bone scan was needed to confirm the diagnosis. It is divided into 4 types or 4 periods according to MRI findings: stress reaction, incomplete fracture, complete fracture, and pseudarthrosis. For patients with incomplete, complete, and juvenile stress fractures of the lumbar pedicle without nerve root irritation, the majority of claims preferred conservative treatment and the healing rate of fracture was high; for patients with bilateral pseudarthrosis and with nerve root irritation as well as patients who failed to the conservative treatment, surgical management was advocated and the operation result is good. Conclusion Stress fracture of the lumbar pedicle as one of the causes of low back pain is extremely rare, and is easily missed clinically. Surgery or conservative management should be selected based on type of fracture and specific condition of the patient, the treatment results are satisfactory.
ObjectiveTo investigate the association between the stress-induced hyperglycemia ratio (SHR) and all-cause, cardiovascular, and diabetes-related mortality in patients with advanced cardiovascular-kidney-metabolic (CKM) syndrome, and to evaluate the value of SHR as an independent prognostic marker. MethodsThis retrospective cohort study used data from the 1999–2018 U.S. National Health and Nutrition Examination Survey (NHANES). A total of 2 135 patients with advanced CKM (stages 3 and 4) were included. Kaplan-Meier analysis and multivariable Cox regression models were applied to assess the relationship between SHR and mortality outcomes. Restricted cubic spline (RCS) analysis was employed to explore potential non-linear associations. Subgroup analyses were conducted to identify possible effect modifiers. ResultsOver a mean follow-up of 248 months, 674 all-cause, 198 cardiovascular, and 31 diabetes-related deaths occurred. Elevated SHR was significantly associated with diabetes-related mortality (HR=3.48, P<0.001) in a dose-response manner. SHR exhibited a U-shaped relationship with both all-cause and cardiovascular mortality (non-linearity P<0.001), indicating increased risk at both low and high SHR levels. Subgroup analyses revealed that sex, BMI, and hyperlipidemia significantly modified the association between SHR and diabetes-related death. ConclusionSHR is an independent predictor of mortality risk in patients with advanced CKM syndrome, particularly for diabetes-related death. These findings support the integration of SHR into risk stratification of high-risk CKM populations and provide a basis for metabolic stress-targeted interventions.
Objective To investigate the indication, approaches andpreventionof complications in treatment of female stress urinary incontinence(SUI) with tension-free vaginal tape (TVT). Methods From September 2003 to December 2004, 40 cases of female stress urinary incontinence were treated, including 8 cases in association with cystocele or rectocele and 1 case in association with uterine prolapse. They ranged from 30 to 70 years in age with an average of 56.3years. The disease course was 1.42 years(7.2 years on average). All patients received TVT. In the patients suffering from uterine prolapse and cystocele or rectocele, butterfly-shaped mesh patch was applied. Results All patients achieved satisfactory results.The complications included slight dysuria(2 cases),vesical perforation(1 case) and pelvic hematoma(1 case) and cleared up after treating. All cases were followed up 1 to 15 months and the results were satisfactory. No urinary incontinence and no dysuria reoccurred. Conclusion TVT is effective for SUI.
Objective To investigate the detailed biomechanics of TiNi shape-memory sawtooth-arm embracing plate (TiNi SMA) by comparing with l imited-contact dynamic compression plate (LC-DCP) and static interlocking intramedullary nail (SIiN), so as to provide theoretical evidence for cl inical appl ication. Methods Eight paired cadaveric femurs immersed in formaldehyde were harvested from eight specimens of adults. After making X-ray films and modeling midpiece transverse fracture, one side randomly was fixed by TiNi SMA (group A) and SIiN (group C) orderly, the other side was fixed by LC-DCP (group B). The axial compression, three-point bending (pressed from plate side and opposite side both of group A and group B, from inside of group C), and torsion were tested, and the stress shielding rate was compared. Results At every classified axial compression load, the strains of group A were greater than those of group B and group C (P lt; 0.05), the displacements of group A were greater than those of group B and group C (P lt; 0.05) except 100 N. At every classified three-point bending moment, the displacement of group A were greater than those of group B and group C pressed both from two sides, but there was no difference when pressing from two sides under the same load of group A (P gt; 0.05). At every torsion moment, the torsion angels of group A were greater than those of group B (P lt; 0.05), but equal to those of group C (P gt; 0.05). At 600 N of axial compression load, the stress shielding rates of groups A, B, C were 48.30% ± 22.99%, 89.21% ± 8.97%, 95.00% ± 3.15%, respectively, group A was significantly less than group B and group C (P lt; 0.01). Conclusion The anti-bending abil ity of TiNi SMA is weaker than LC-DCP and SIiN; the anti-torsion abil ity of TiNi SMA is weaker than SIiN, but TiNi SMA is a center-type internal fixation, the superior stress shielding rate and micromovement promote the stress stimulation of fracture, which makes it an ideal internal fixation device.
Objective To explore the influence of different stress environmentson the growth of tissue engineering blood vessels in vivo． Methods The engineering vascular scaffolds were prepared with the porcine small intestinal submucosa(SIS) wrapping vascular endothelial cells and smooth muscle cells，which were implanted into the subcutaneous tissue(subcutaneous group), the femoral quadriceps(intramuscular group), and sheathed the femoral artery(perivascular group) respectively. Four weeks postoperatively, these cultured tissues were harvested, and evaluated by macroscopic observation and histology detection. Results The cultivated tissues in different stress environments had obvious difference in respectof the tubular configuration, cellular proliferation and tissue shape. In subcutaneous group, the wall structure integrity, seed cell proliferation and SIS scaffold decomposition were poor, lumen surface was covered without endothelial cells; in intramuscular group, integrity tubular structure had formed, seed cell proliferation was found to a certain extent, lumen surface was covered with sparseendothelial cells, and a little SIS scaffold was found, cellular and fiber structured arranged irregularly; in perivascular group, vascular-like structure formed, the seed cell growth and proliferation were good, the lumen surface was completely covered with endothelial cells, the smooth muscle cells were in good morphologicaldistribution, the antihydrostatic pressure was 247.0±35 kPa，showingsignificant differences when compared with subcutaneous group(67.0±5.8 kPa) and intramuscular group(104.0±7.6 kPa) (Plt;0.01).The total scoring of tissue engineering blood vessel formation in subcutaneous group, intramuscular group and perivascular group were 5.529±0.272，8.875±0.248 and 14.824±0.253 respectively, and the differences among them were significant (P lt; 0.05). Conclusion Stress excitation has a great influence on the cellular proliferation and the growth of tissue engineering blood vessel in vivo.
Objectives The Faculty of Medicine of National Yang-Ming University is committed to helping students enhance intellectual, personal, and professional development while fully supporting students during this time of intense training and personal growth. The student portfolio system has sprung from the Faculty’s devotion to innovative medical education initiatives and is one attempt to fulfill our obligations to our past and future, to our society and to the rest of the world. The basic approach toward helping students enhance their cognitive, personal and professional development while coping with internal or external environmental stressors would be to identify and provide supportive elements within medical education. In order to achieve the goal, we explore possible factors, both micro and macro elements of the students’ environment, which may contribute to their stress, mental disturbances and status attainment. Methods We established a multi-dimensional and multi-functional “student portfolio” framework that integrated dynamic, timely, and continuous exploration as well as modification of students’ learning processes, mental status and environmental impact. The first step in this project was to locate and validate students’ “red flag”: factors that contributed to their stress, mental disturbances and status attainment. Self reports by the students were used for the “risk factor” analyses. Results Status achievement by students was associated with their parents’ educational attainment, in particularly the educational attainment of their mothers. This was associated with the student’s stress, mental disturbance, attitude toward life and status achievement. The educational attainment of the parents of our students increased yearly, suggesting that the social economic status and marital matching situation of individuals were associated with social environment and time. Conclusions The associations of cognitive processes, family condition, societal values, mental status and learning behaviors are intertwined dynamically with time and environment. However, longitudinal and multi-dimensional research in this area is very limited. It is important for contemporary medical education to develop a framework for the theory and practice of the development of medical students that leads to their attainment of professional, sociological, and psychological competencies. This study suggests that particular social economic status factors may increase the risk that medical students will experience stress, mental disturbances, and status attainment.