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ObjectivePrevious studies on glioblastomas (GBMs) have not reached a consensus on peritumoral edema (PTE)’s influence on survival. This study evaluated the PTE index’s prognostic role in newly diagnosed GBMs using a well-designed method.MethodsSelected patients were reviewed after a rigorous screening process. Their general information was obtained from electronic medical records. The imaging metrics (MTD, TTM, TTE) representing tumor diameter, laterality, and PTE extent were obtained by manual measurement in Syngo FastView software. The PTE index was a ratio of TTE to MTD. Multiple variables were evaluated using analysis of variance and Cox regression model.ResultsOf 143 patients, 62 were included in this study. MGMT promoter methylation and tumor laterality were both independent prognostic factors (p = 0.020, 0.042; HR = 0.272, 2.630). The lateral tumors’ index was higher than that of the medial tumors (57.7% vs. 42.6%, p = 0.027). Low-index tumors were located in relatively medial positions compared with high-index tumors (TTM, 4.9 vs. 12.8, p = 0.032). This finding indicated that the PTE index tended to increase with tumor laterality. Moreover, the patients with low-index tumors had a significant survival disadvantage in the univariate analysis but not in the multivariate analysis (p = 0.023, 0.220). However, further analysis found that the combination of tumor laterality and PTE statistically stratified the survival outcome. The patients with lateral high-index tumors survived significantly longer (p = 0.022, HR = 1.927).ConclusionsIn contrast with the previous studies, this study recommends combining PTE and tumor laterality for survival stratification in newly diagnosed GBMs.  相似文献   
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《Injury》2021,52(4):705-712
Intramedullary nails are the common treatment options for femoral intertrochanteric fractures. However, aseptic loosening is considered to be one of the primary forms of failure that can be caused by the stress shielding between the bone and implants. The matching in mechanical properties of implant and bone is a key issue to prevent this failure. Polyetheretherketone (PEEK) and Function-graded (FG) materials are widely used in clinical because of their excellent mechanical properties. In this study, to investigate the biomechanical behaviors of intramedullary nails made of Ti-6Al-4V alloy, Stainless Steel (SS), PEEK and two FG materials, three-dimensional finite element models of intertrochanteric fracture femur with intramedullary nail were constructed with ABAQUS. The maximum von Mises stress on the femoral fracture surface fixed by PEEK intramedullary nail was the largest, followed by FG intramedullary nail, which help stimulate bone growth and subsequently reduce fracture healing time. Compared with traditional metal intramedullary nails, PEEK and FG implants might increase von Mises stress along the same path in the proximal femur. The results showed that PEEK and FG intramedullary nails obviously changed the stress distributions in the bone and reduced stress shielding. This finding indicated that PEEK and FG intramedullary nails have the potential to become alternatives to the conventional metal intramedullary nails.  相似文献   
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目的:观察慢性乙型肝炎患者乙型肝炎病毒e系统状态和复制指标在肝纤维化发生过程中的变化及其与血清纤维化标志的关系,探讨它们在肝纤维化发生过程中的作用及其可能的临床意义.方法:188例慢性乙型肝炎患者根据肝纤维化程度分为S0~S4期等5组,分别用定量PCR及放免法检测患者血清中HBV-DNA及肝纤维化标志透明质酸、Ⅳ型胶原、Ⅲ型前胶原和层粘连蛋白的含量;HBeAg和抗-HBe采用酶联免疫吸附法(ELISA)检测,并观察其在不同肝病理纤维化分期时的变化.结果:随着肝纤维化程度加重,血清HBV-DNA含量逐渐升高,从S1期开始显著增加(P<0.01);而HBeAg阳性率逐渐降低,S3、S4期较S0显著减少(P<0.05和P<0.01);抗-HBe阳性率呈相反的变化趋势,在S3和S4期的阳性率明显高于S0期(P<0.05和P<0.01).血清HBV-DNA( )HBeAg( )组血清纤维化标志最低,HBV-DNA(-)抗-HBe( )组最高,两者差异有显著性(P<0.01).结论:HBV复制和e系统状态的改变与肝纤维化程度密切相关,肝内病毒复制标志与血清纤维化标志联合检测,对于判断肝纤维化程度和指导抗病毒治疗有重要的价值.  相似文献   
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目的:分析医院病原菌的结构和耐药的变迁趋势,探讨病原菌的变迁与临床抗菌药物使用的关系。方法:对解放军总医院第一附属医院1995年以来11年临床标本病原菌的分离鉴定结果进行统计分析,结合同期临床抗菌药物的使用强度,分析病原菌变迁与抗菌药物使用的相关性。结果:11年间从临床标本中共分离出病原菌15914株。①G 菌中金黄色葡萄球菌(金葡菌)和耐甲氧西林金葡菌(MRSA)的构成比上升趋势明显,凝固酶阴性葡萄球菌(CNS)和肠球菌属的构成比波动幅度较大,但变化趋势不明显。G-菌中,铜绿假单胞菌的构成比虽有波动,但始终维持在高水平;大肠杆菌和变形杆菌的构成比明显下降,不动杆菌的构成比明显上升。②1995年构成比最高的3种病原菌依次为大肠杆菌、铜绿假单胞菌和金葡菌,2005年变为铜绿假单胞菌、金葡菌和不动杆菌。③我院抗菌药物的使用强度在2005年达70DDD/100人天,使用最多的药物种类为喹诺酮类、二代头孢菌素和含酶抑制剂的三代头孢菌素;单一品种药物为左氧氟沙星、头孢呋辛和阿奇霉素。④大环内酯类、糖肽类、碳青霉烯类和3代头孢/抑制剂等药物的使用强度变化与多种病原菌构成比的变化呈显著正相关,MR-SA构成比的变化与多种药物使用强度变化呈显著正相关。结论:常见病原菌的耐药水平逐渐升高,将会增大抗感染治疗的难度;抗菌药物使用强度的变化有可能导致病原菌结构和耐药水平的变化。  相似文献   
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CD14+单核细胞人类白细胞抗原DR表达率与脓毒症关系的研究   总被引:15,自引:0,他引:15  
目的了解烧伤延迟复苏时CDl4^+单核细胞人类白细胞抗原DR(HLA—DR)表达率的变化,分析其与脓毒症的关系。方法选择烧伤面积大于30%TBSA的25例烧伤延迟复苏患者,于伤后1、3、7、14、28d取外周血,其中7例患者住院期间并发脓毒症,于脓毒症发生后连续2d亦取其外周血。另取20例健康体检者外周血作为对照。流式细胞仪检测CD14^+单核细胞HLA.DR表达率,酶联免疫吸附测定法检测血浆中肿瘤坏死因子α(TNF—α)、白细胞介素10(IL-10)的浓度。结果非脓毒症患者伤后1、3、7、14、28dCD14^+单核细胞HLA—DR表达率分别为(15±6)%、(74±5)%、(264±17)%、(284-16)%、(474-16)%,明显低于健康体检者[(924±10)%,P〈0.01];脓毒症患者发生脓毒症后1、2d,该指标亦明显低于健康体检者及非脓毒症患者伤后1、7、14、28d(P〈0.01)。脓毒症患者TNF—d检出率及TNF—α、IL-10浓度,均高于非脓毒症患者和健康体检者(P〈0.05或P〈0.01)。伤后1、7、28d,外周血CD14^+单核细胞HLA—DR表达率与IL—10浓度呈显著负相关(r分别为-0.9963、-0.7459、-0.8474,P〈0.01)。结论烧伤延迟复苏患者免疫功能低下,促炎性介质释放量增加,并发脓毒症时则更为严重。外周血CD14^+单核细胞HLA—DR表达率可作为动态检测患者免疫功能状态的有效指标。  相似文献   
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目的探讨离体培养脊髓片的理想厚度和大鼠的最佳周龄。方法通过不同周龄的大鼠(1周、2周、3周、4周龄各10只,共40只),以及不同厚度(切片厚度分为:100μm、200μm、300μm以及400μm 4种)的脊髓组织切片培养,采用MTT技术进行脊髓片培养细胞的活性鉴定,观察脊髓片培养不同时间点其神经细胞的活性。结果1~7 d鼠龄的脊髓组织片培养1~14 d时细胞活性最高,但其神经细胞结构形态容易受到破坏,不利于观察,且在培养超过14 d时神经细胞活性明显下降;2~3周鼠龄的脊髓组织片培养细胞,在培养14 d后仍有较高的神经细胞的活性并保持较好的细胞形态结构;1~4各周龄组大鼠200μm和300μm左右厚度的脊髓片培养神经细胞活性最稳定(85%~95%)。结论进行离体脊髓片培养,选择7~14 d(即1~2周龄)大鼠作为取材对象较为理想,选择200μm~300μm切片厚度的脊髓片进行培养较为合适。  相似文献   
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BACKGROUND: Craniocerebral injury always accompanies with singultus, while frequent singultus may cause increased intracranial pressure. Simultaneously, respiratory alkalosis and cerebral hypoxia induced by respiratory disorder may aggravate craniocerebral injury. OBJECTIVE: To observe the therapeutic effects of intranasal cavity drip infusion of aminazine and intramuscular injection on singultus following craniocerebral injury. DESIGN: Contrast observation. SETTING: Department of Neurosurgery, Xi'an Aerospace General Hospital. PARTICIPANTS: A total of 102 patients with singultus following craniocerebral injury were selected from the Department of Neurosurgery, Xi'an Aerospace General Hospital from June 2001 to June 2006. Patients with craniocerebral injury were diagnosed with CT examination and randomly divided into nasal cavity medication group (n =62) and intramuscular injection group (n =40). There were 44 males and 18 females in the nasal cavity medication group and their mean age was (33±4) years; while, there were 26 males and 14 females in the intramuscular injection group and their mean age was (29±4) years. All patients and their relatives provided the confirmed consent. METHODS: Patients in the nasal cavity medication group were slowly dripped aminazine solution into bilateral nasal cavity with the dosage of 12.5 mg (0.5 mL). Patients who had no obvious effect or had mild improvement received the treatment once every 6 hours. The treatment was stopped if symptoms were also observed after the fifth medication. In addition, patients in the intramuscular injection group received intramuscular injection of 50 mg aminazine. Patients who had no obvious effect or had mild improvement received the treatment once every 6 hours. The treatment was changed if symptoms were also observed after the fifth medication. MAIN OUTCOME MEASURES: Therapeutic effects of different medications in the two groups. RESULTS: All 102 patients were involved in the final analysis. Effective rate in the nasal cavity medication group was higher than that in the intramuscular injection group, and there was significant difference (χ2= 11.882, P < 0.01). At 6 hours after onset of singultus, effective rate in the nasal cavity medication group was higher than that in the intramuscular injection group, and there was significant difference (χ2 =8.188, P < 0.01). CONCLUSION: Therapeutic effects of intranasal cavity drip infusion of aminazine on singultus following craniocerebral injury are superior to those of intramuscular injection.  相似文献   
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目的:了解烧伤病区铜绿假单胞菌(Pseudomonas aeruginosa,PA)感染的分子流行病学特征。方法:采用脉冲场凝胶电泳(PFGE)分型的方法,对15株分离自烧伤临床病人的多重耐药PA染色体组DNA进行分析。结果:15株检测菌株中有9株菌分别属于两种不同的PFGE图谱类型,具有同源性的菌株占测试菌株的60%。结论:导致我院烧伤患者感染多重耐药的PA中有同源性的比例较高,提示在烧伤救治中采取有针对性的措施,防止烧伤病房内的交叉感染对于降低烧伤感染率、提高烧伤救治水平具有重要意义。  相似文献   
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