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81.
Vascular endothelialgrowth factor ( VEGF) is amultifunctional cytokine thatexerts in vivo a key rolein physiologicalneoangiogenesisduring embryonicde-velopmentor the female cycle and pathologicalneoan-giogenesis of many diseases including hypervascular-ized tumors,rheumatoid arthritis,and retinopathiesdiseases[1— 3] by stimulating endothelial cell prolifera-tion and vessel hyperpermeability.VEGF exists asone of five different isoforms,VEGF1 2 1 ,VEGF1 65 ,VEGF1 83,VEGF1 89and VEGF2 …  相似文献   
82.
还原型谷胱甘肽治疗尿毒症贫血的初步探讨   总被引:1,自引:0,他引:1  
目的 观察外源性还原型谷胱甘肽对尿毒症贫血的治疗效果。方法 将 42例尿毒症贫血患者随机分为两组。两组患者均给予重组人红细胞生成素 (r- Hu EPO) 30 0 0 U,每周两次皮下注射 ,疗程 12周。治疗组患者同时静脉给予外源性还原型谷胱甘肽 (GSH) 12 0 0 mg,每周两次 ,疗程 12周。于治疗前和治疗后抽静脉血测定血红蛋白 (Hb) ,红细胞 (RBC)和红细胞压积 (HCT)水平。结果  r- Hu EPO治疗后两组患者 HB,RBC和 HCT水平均显著上升 (P<0 .0 1)。 GSH治疗组 Hb,RBC和 HCT水平与对照组比较上升明显 (P<0 .0 5 ) ,治疗组 Hb,RBC和HCT的上升幅度高于对照组 (P<0 .0 5 )。结论 外源性还原型谷胱甘肽能显著提高 r- Hu EPO治疗肾性贫血的疗效 ,GSH可能是治疗尿毒症贫血的有效药物。  相似文献   
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BackgroundThe aim of this study is to compare the long-term functional outcome and quality of life between total knee arthroplasty (TKA) and fixed-bearing unicompartmental knee arthroplasty (UKA) for the treatment of isolated medial compartment osteoarthritis.MethodsBetween 2000 and 2008, a total of 218 patients underwent primary UKA at our tertiary hospital. A TKA group was matched through 1:1 propensity score matching and adjusted for age, gender, body mass index, preoperative knee flexion, and function scores. All patients had medial compartment osteoarthritis. The patients were assessed with the range of motion, Knee Society Knee Score and Knee Society Function Score, Oxford Knee Score, Short Form-36 physical component score (PCS) and mental component score preoperatively, at 6 months, 2 years, and 10 years. Patients’ satisfaction, expectation fulfillment, and minimal clinically important difference were analyzed.ResultsThere were no differences in baseline characteristics between groups after propensity score matching (P > .05). UKA had greater knee flexion at all time points. Although the Knee Society Function Score was superior in UKA by 5.5, 3, and 4.3 points at 6 months, 2 years, and 10 years, respectively (P < .001), these differences did not exceed the minimal clinically important difference (Knee Society Knee Score 6.1). There were no significant differences in the Oxford Knee Score and Short Form-36 physical component score/mental component score. At 10 years, similar proportions of UKA and TKA were satisfied (90.8% vs 89.9%, P = .44) and had expectation fulfillment (89.4% vs 88.5%, P = .46). Between 2 and 10 years, all function scores deteriorated significantly for both groups (P < .01).ConclusionUKA and TKA are excellent treatment modalities for isolated medial compartment osteoarthritis, with similar functional outcomes, quality of life, and satisfaction at 10 years.  相似文献   
84.
BackgroundPrevious studies evaluating weight changes following total knee arthroplasty (TKA) were performed on heterogenous cohorts. However, no study has evaluated weight changes in a cohort of simultaneous-bilateral TKA (SB-TKA) patients. This study aimed to evaluate the prevalence of patients who lost or gained weight, determine if postoperative weight change influences functional outcome, and identify predictors of weight change after SB-TKA.MethodsProspectively collected registry data of 560 patients who underwent SB-TKA were reviewed. Patients were assessed preoperatively, at 6 months, and 2 years using the Knee Society Score, Oxford Knee Score, Short-Form 36, and range of motion. Change in body mass index (BMI) >5% was used to categorize patients into 3 groups: lost, maintained, or gained weight. Analysis of variance, Kruskal-Wallis test, and chi-squared test were used to compare functional outcomes between groups. Multivariable logistic regression evaluated predictors for postoperative weight changes.ResultsAt 2 years, 59% of patients maintained weight, 28% of patients gained weight, and 13% of patients lost weight. All groups experienced similar improvements in functional outcomes, rates of minimal clinically important difference attainment, and patient satisfaction (P > .05). Older patients were more likely to gain weight (P < .05). Patients with higher preoperative BMI were more likely to gain weight (P < .05) and less likely to lose weight (P < .05). Patients with greater preoperative comorbidities were less likely to lose weight (P < .05).ConclusionUp to 41% of patients experience significant weight changes after SB-TKA. Older patients with higher preoperative BMI were more likely to gain weight, while higher preoperative BMI with more comorbidities were less likely to lose weight following SB-TKA; however, postoperative weight changes do not appear to affect functional outcomes.Level of EvidenceIII, therapeutic study.  相似文献   
85.
目的探讨完全右半肝-左半肝劈离式肝移植在成人-成人或成人-大体重儿童中的临床应用。方法回顾2019年1月至12月间首都医科大学附属北京友谊医院完成的4例完全右半肝-左半肝劈离式肝移植的供受者临床资料,分析劈离式肝移植的手术方式、冷缺血时间、手术时间、术中输血量,观察患者术后并发症及相关预后。结果4例完全右半肝-左半肝劈离式肝移植的受者包括3例成人和1例大体重儿童(45 kg),年龄范围14~48岁,体重范围45~61 kg,终末期肝病模型评分分别为21、12、41和30分。移植物质量与受者体质量比为0.85%~1.35%。冷缺血时间457~650 min,手术时长460~575 min。4例患者移植术后早期肝功能恢复顺利,均未出现小肝综合征。随访至术后6个月,其中1例出现胆道吻合口漏,经内镜逆行胰胆管造影术治疗后治愈;1例出现胆道狭窄,经皮肝穿刺胆道引流术治疗后反复胆道感染;1例术后6个月死于肺部感染。结论在严格病例选择的情况下,可以开展完全右半肝-左半肝劈离式肝移植。  相似文献   
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The concentration of eco-toxic zinc oxide nanoparticles (nZnO) in aquatic ecosystems is increasing, and an effective method for their removal is needed. We hypothesize that microalgal cells may act as nZnO vehicles—if the nZnO concentration does not affect their swimming ability—enabling Zn diffusion and sedimentation. We conducted experiments using flasks connected via a U-type vessel; the first flask contained nZnO suspensions and second flask contained artificial seawater, respectively. We added microalgae to the first flask and illuminated the second. The microalgae appeared to promote sedimentation. However, only a few microalgal cells passed via phototaxis into the second flask, so the detection of nZnO or Zn ions in the second flask was not possible. Therefore, to confirm whether the microalgae affect Zn transportation, a more accurate method to detect nZnO or Zn ions at very low concentrations is needed.

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89.
目的探讨65岁及以上人群血铅水平与认知功能受损的关联。方法研究对象来自2017-2018年在我国9个长寿地区开展的“老年健康生物标志物队列研究”,最终将1684名血铅和认知功能数据完整的65岁及以上人群纳入本研究。通过问卷调查和体格检测,收集调查对象的人口学特征、生活方式、健康状况及认知功能评分等信息;同时采集调查对象的静脉血以检测血铅水平。根据血铅水平的四分位数将调查对象分为4组(Q1-Q4组),采用多因素logistic回归模型分析血铅浓度与认知功能受损的关系,采用限制性三次样条检验血铅浓度与认知受损之间是否存在非线性关联。结果1684名研究对象年龄为(83.1±11.1)岁,其中女性843名(50.1%);认知功能受损者191名(11.3%)。调整相关混杂因素后,老年人血铅浓度每升高10μg/L,认知功能受损患病风险OR(95%CI)值为1.05(1.01~1.10);与血铅浓度Q1组老年人相比,血铅浓度较高者认知功能受损的患病风险较高,Q2,Q3,Q4组的OR(95%CI)值分别为1.19(0.69~2.05)、1.45(0.84~2.51)和1.92(1.13~3.27)。结论我国9个长寿地区65岁及以上老年人血铅水平与认知功能受损患病风险存在关联。  相似文献   
90.
We report the prevalence rates for dementia and Alzheimer's disease (AD) obtained from a probability sample survey of 5,055 noninstitutionalized older persons in Shanghai, China. A two-stage procedure was used for case finding and case identification. A Chinese version of the Mini-Mental State Examination was used to determine cases of possible dementia. Three different cutoff points on this mental status test were used depending on the respondent's level of education. Clinical evaluations, based on functional assessments and psychiatric interview, medical and neurological examinations, three standardized mental status tests, and a selected group of psychometric tests, were made in the second stage of the study to ascertain the clinical diagnosis of dementia and AD utilizing the Diagnostic and Statistical Manual for Mental Disorders, edition 3 and National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, respectively. The prevalence rate of dementia in persons 65 years and older was 4.6%. Clinically diagnosed AD accounted for 65% of the subjects with dementia. These findings indicate that the prevalence of dementia in Shanghai is very much higher than figures published earlier for China and Japan, and at the lower part of the range of values reported for community residents in the United States and other Western countries, but less than half of that reported in the recently published survey of the elderly in East Boston. Increasing age, gender (female), and low education are each highly significant and independent risk factors for dementia. One hypothesis to explain the increased prevalence in elderly women who had received no formal education invokes the possibility of an effect of early deprivation, perhaps lowering brain "reserve," allowing the symptoms of dementia to appear at an earlier date during disease progression.  相似文献   
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