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91.
Patients with diabetes often experience visual defects before any retinal pathologies are detected. The molecular mechanism for the visual defects in early diabetes has not been elucidated. Our previous study reported that in early diabetic retinopathy (DR), rhodopsin levels were reduced due to impaired 11-cis-retinal regeneration. Interphotoreceptor retinol-binding protein (IRBP) is a visual cycle protein and important for 11-cis-retinal generation. IRBP levels are decreased in the vitreous and retina of DR patients and animal models. To determine the role of IRBP downregulation in the visual defects in early DR, we induced diabetes in transgenic mice overexpressing IRBP in the retina. IRBP overexpression prevented diabetes-induced decline of retinal function. Furthermore, IRBP overexpression also prevented decreases of rhodopsin levels and 11-cis-retinal generation in diabetic mice. Diabetic IRBP transgenic mice also showed ameliorated retinal oxidative stress, inflammation, apoptosis, and retinal degeneration compared with diabetic wild-type mice. These findings suggest that diabetes-induced IRBP downregulation impairs the regeneration of 11-cis-retinal and rhodopsin, leading to retinal dysfunction in early DR. Furthermore, increased 11-cis-retinal–free opsin constitutively activates the phototransduction pathway, leading to increased oxidative stress and retinal neurodegeneration. Therefore, restored IRBP expression in the diabetic retina may confer a protective effect against retinal degeneration in DR.  相似文献   
92.
93.
Background ContextPrevious studies have reported conflicting results for the relationships between anthropometric adiposity indexes and bone mineral density, based on dual-energy X-ray absorptiometry (DXA). However, few studies were published based on quantitative computed tomography (QCT), especially for Chinese population.PurposeTo evaluate the associations of spine bone mineral density (BMD) with body mass index (BMI), waist circumstance (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) using QCT.Study Design/SettingA Cross-sectional study.Patient SampleAround 3,457 participants in multiple communities across 7 administrative regions of China.Outcome MeasuresSpine BMD was measured using QCT, and the classification of osteoporosis was defined as follows: 1) osteoporosis if BMD <80mg/cm3, 2) osteopenia if BMD 80–119 mg/cm3, and 3) normal bone mass if BMD≥120 mg/cm3.MethodsThis study was conducted using convenient sampling between 2013 and 2017. Multivariable linear regression model and logistic regression models were used for the associations of continuous and categorical BMD, respectively.ResultsAround 3,405 participants were included in the final analyses, including 1,272 males and 2,133 females, with spine BMD of 111.00±35.47 mg/cm3 and 99.38±40.60 mg/cm3, respectively. Spine BMD decreased significantly with the increase of ABSI in females (adjusted β, ?5.74; 95% confidence interval [CI], ?8.50 to ?2.98), and this trend also was kept in females aged at less than 60 years (adjusted β, ?14.54; 95% CI, ?20.40 to ?8.68), and females with age ≥60 years (adjusted β, ?7.59; 95% CI, ?10.91 to ?4.28). However, this inverse association was observed only in males with age ≥ 60 years (adjusted β, ?5.19; 95% CI, ?10.08 to ?0.29). Except ABSI, negative associations of Spine BMD with WC (adjusted β, ?0.46; 95% CI, ?0.77 to ?0.15), WHR (adjusted β, ?6.25; 95% CI, ?10.63 to ?1.86), WHtR (adjusted β, ?6.80; 95% CI, ?11.63 to ?1.97) were shown in females aged at <60 years, and positive association with BMI in males with age ≥60 years (adjusted β, 0.92; 95% CI, 0.29–1.55).ConclusionsABSI had more remarkable association with spine BMD, compared with the other four indexes.  相似文献   
94.
ObjectiveTo explore the effect of a PEEK material‐based external fixator in the treatment of distal radius fractures with non‐transarticular external fixation.MethodsThere were 48 patients in this prospective comparative study. They were divided into two groups according to the materials used: the PEEK group and the titanium group. Wrist dorsiflexion, palmar flexion, pronation, supination, radial deviation, ulnar deviation, grip strength of the palm on the affected side, kneading force, Visual Analogue Scale/Score (VAS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, operation time, frequency of fluoroscopy procedures, and X‐ray results were compared between the two groups. Functional recovery was evaluated at the last follow‐up according to the wrist joint evaluation criteria.ResultsThe baseline data were comparable between the two groups, and no significant differences were found in age, sex, fracture types (P > 0.05). There was no significant difference between the two groups in the results of DASH, grip strength, and recovery of pinch force and wrist function (dorsiflexion, clavicle, ulnar deviation, deviation, pronation, and supination) (P > 0.05). Normal limb function was achieved in the two groups of patients at an average of 6 weeks after surgery, and there was no significant difference in X‐ray examination radial height (10.60 ± 1.59 vs 11.00 ± 1.53, P = 0.687), radial inclination (1.11 ± 0.24 vs 1.12 ± 0.24, P = 0.798), volar tilt (10.33 ± 2.13 vs 10.00 ± 2.08, P = 0.660), ulnar variance (20.87 ± 3.00 vs 20.38 ± 3.04, P = 0.748), and step‐off persistence (1.73 ± 0.69 vs 1.68 ± 0.72, P = 0.425) between the two groups (P > 0.05). However, the operation time (54.80 ± 12.20 vs 85.23 ± 15.14, P = 0.033) and number of fluoroscopy procedures (36.93 ± 6.89 vs 64.77 ± 9.74, P = 0.000) in the PEEK group were significantly reduced compared with those in the titanium group.ConclusionCompared with the traditional titanium external fixator, the PEEK composite external fixator has advantages, such as a shorter operation time and fewer fluoroscopy procedures when used to treat different types of distal radius fracture.  相似文献   
95.
目的探讨低氧环境对椎间盘自发性吸收的影响及其作用机制。方法取SPF级成年日本大耳兔9只,雌雄不限,平均体质量2 kg。将兔处死后取脊柱髓核组织,经消化、分离、培养后获得传代髓核细胞,将生长良好的髓核细胞制成细胞悬液。根据不同时效的低氧环境将细胞分为5组对照组(常氧浓度下培养6 h)、低氧6 h组(2%O2浓度下培养6 h)、低氧12 h组(2%O2浓度下培养12 h)、低氧24 h组(2%O2浓度下培养24 h)和低氧48 h组(2%O2浓度下培养48 h)。采用实时聚合酶链反应法检测缺氧诱导因子(HIF)-1α、3型酸敏感离子通道(ASIC3)及水通道蛋白3(AQP3)mRNA表达水平,采用流式细胞仪检测各组髓核细胞凋亡情况。采用SPSS 24.0软件对数据进行分析。结果与对照组比较,低氧各组细胞凋亡率均明显升高,差异均有统计学意义(均P<0.01);与低氧12、24和48 h组比较,低氧6 h组细胞凋亡率最高,差异均有统计学意义(均P<0.01)。与对照组比较,低氧各组细胞HIF-1α和ASIC3 mRNA表达水平均明显上升,AQP3 mRNA表达水平均明显下降,差异均有统计学意义(均P<0.01);与低氧12、24和48 h组比较,低氧6 h组HIF-1α和ASIC3 mRNA表达水平最高,差异均有统计学意义(均P<0.01)。结论短时间低氧环境可以促进髓核细胞凋亡,从而加速椎间盘突出组织自发性吸收进程,其机制可能与HIF-1α和ASIC3的表达增加及AQP3的表达下降有关。  相似文献   
96.
BackgroundThis study investigated a comfortable suture angle (CSA) with optimized trocar position for closing the defect during renorrhaphy in retroperitoneal laparoscopic partial nephrectomy (LPN). The feasibility, usefulness, and safety of achieving the CSA with modified trocar position were determined for different tumor types.MethodsTwo optimized trocar positions were introduced for different tumor types. A suture angle was based on the tumor plane of the superficial parenchyma defect and the line formed by the needle holder. Preliminary surgical simulations determined a CSA that combined the least suture time with the greatest ease of performance. Achieving the CSA was attempted during renorrhaphy of 106 enrolled patients undergoing retroperitoneal LPN. Patients’ characteristics, operative features, and follow-up information were collected and analyzed.ResultsFor 89 (83.96%) patients, a CSA was successfully reached and parenchyma recovered. The remaining 17 patients were successfully sutured, but the attempt to achieve a CSA failed. For the CSA group, the suture, clamping, and overall operative times were significantly less than that of the non-CSA patients. The groups were similar regarding estimated blood loss, positive surgical margin, and rates of glomerular filtration reduction and complications. Univariable analyses determined that tumor location, growth pattern, and R.E.N.A.L. nephrometry score (RNS) may influence the success of this approach. Multivariable analyses indicated that only tumor location and RNS were independent factors affecting successful achievement of the CSA.ConclusionsThrough different kidney position changes, the CSA could be used to ease the suture process. It is feasible and safe to perform a CSA with optimized trocar position during LPN. Tumor location and RNS may influence the approach to get a CSA.  相似文献   
97.
陈明燕  杨星    杨敬源  周全湘  杨曦  屈芳  熊燕 《现代预防医学》2021,(20):3678-3682
目的 探讨农村老年人腹型肥胖及血脂水平对动脉硬化的交互影响,为动脉硬化的防治提供参考依据。方法 采用多阶段抽样方法选取贵州省2个县(区)内5个乡镇共1 035名60岁及以上老年人为研究对象,进行问卷调查、现场体格检查、实验室检测和动脉硬化检测,采用SPSS 24.0软件进行χ2检验和非条件logistic回归分析贵州农村老年人腹型肥胖、血脂水平及其交互作用对动脉硬化的影响。结果 1 035名老年人中检出动脉硬化对象942人,检出率为91.01%。腹型肥胖老年人动脉硬化检出率94.25%(606人);TG异常老年人动脉硬化检出率97.53%(158人)。多因素logistic回归分析结果显示,控制年龄、性别、婚姻状况、是否高血压等因素后,腹型肥胖者(OR = 2.018,95%CI:1.188~3.428),TG异常者(OR = 3.350,95%CI:1.148~9.774)与老年人动脉硬化患病高风险相关。交互作用分析结果显示TG×腹型肥胖对老年人发生动脉硬化存在相乘交互作用(P<0.05),(OR = 3.526,95%CI:1.053~11.810)。结论 腹型肥胖、TG异常是动脉硬化的独立影响因素,且腹型肥胖与血脂水平对老年人患动脉硬化具有相乘交互作用。  相似文献   
98.
用改良的单细胞细胞毒试验研究了IL-2和IFN_(?)对人外周血淋巴细胞NK的增强作用及共同增强作用。结果表明,IL-2或IFN_a单独预处理人外周血淋巴细胞(PBL)均不影响淋巴细胞与靶(K_(562))细胞的结合率,但能显著增加与靶细胞结合的淋巴细胞的杀伤率;同时用IL-2和IFN_a预处理人PBL后,淋巴细胞与靶细胞的结合率也没有显著改变,但结合的淋巴细胞的杀伤率显著高于单独用IL-2或IFN_a预处理后淋巴细胞的杀伤率,而且IL-2和IFN_a的增强作用存在加和性。这提示,IL-2和IFN_a能分别激活不同的NK细胞,即,NK细胞在其激活信号方面存在异质性。  相似文献   
99.
肺癌的治疗方案与预后取决于肺癌的病理类型。本文按照概率型的数学模型──最大似然法,建立计算机鉴别肺癌病理类型的数学模型,用BASIC语言编制诊断程序。结果表明该方法的诊断正确率高于临床,为肺癌病理类型的分类提供了一种简便、快捷、实用的方法。  相似文献   
100.
目的:研究多节段脊柱后部结构对腰椎旋转稳定性的影响。方法:选用7具成人新鲜尸体脊柱标本(L1~S1),采用单侧多节段逐步切除腰椎后部结构的方法,形成7种状态,从单侧多节段开窗至全椎板及双侧小关节切除等。通过脊柱三维运动试验机施加10Nm的扭转载荷,使脊柱产生左、右轴向旋转运动。结果:全椎板加双侧小关节部分切除后,腰椎旋转稳定性受到显著影响。结论:除小关节骨性结构及关节囊外,椎板及后部韧带结构对维持腰椎旋转稳定性亦有重要作用  相似文献   
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