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21.
The 4 allele of apolipoprotein E gene is a major risk factor for Alzheimer's disease. However, the mechanism by which the E4 isoform of apolipoprotein E increases the risk of Alzheimer's disease is poorly understood. To determine whether the isoform-specific effects of apolipoprotein E may be mediated via clearance of bound β-amyloid, we examined the uptake of β-amyloid 1–40 into Chinese hamster ovary cells in the presence or absence of the apolipoprotein E isoforms E2, E3 and E4. Apolipoprotein E2 and E3 treatments were associated with higher association of β-amyloid with cells as compared to treatment with E4. Heparin blocked the association of β-amyloid with cells, as did an antibody to one of the apolipoprotein E receptors (the low-density lipoprotein receptor-related protein).

Thus, the apolipoproteins E2 and E3, but not E4, may play important roles in the clearance of β-amyloid from the extracellular space via the low-density lipoprotein receptor-related protein.  相似文献   

22.
Zusammenfassung. In einer experimentellen Studie wurde bei 10 Schweinen mit einem mittleren K?rpergewicht von 18,9 (15–24) kg eine intraven?se CO2- oder Argon-Embolie mit 10, 20 und 30 ml Gas durchgeführt. Das invasive Monitoring zeigte bei der Gasembolie mit Argon im Gegensatz zur Gasembolie mit CO2 einen st?rkeren Anstieg des pulmonal arteriellen Drucks (p < 0,001), einen st?rkeren Abfall des endexspiratorischen CO2 (p < 0,01), des Herzminutenvolumens (p < 0,01) und des mittleren arteriellen Drucks (p < 0,01). In der Argon-Gruppe (n = 5) starben zwei Tiere nach 20 bzw. 30 ml Bolusgabe. Ein weiteres Tier konnte nach Gabe von 30 ml Bolus erfolgreich reanimiert werden. In der CO2-Gruppe (n = 5) starb weder eines der Tiere noch war eine Reanimation erforderlich. Wenig l?sliche Gase wie Argon sollten in Situationen mit erh?htem Risiko einer Gasembolie nicht angewendet werden. ID=" Dr. T. Junghans Klinik f&uuml;r Allgemein-, Visceral-, Gef&auml;&szlig;- und Thoraxchirurgie Universit&auml;tsklinikum Medizinische Fakult&auml;t der Humboldt-Universit&auml;t Campus Charit&eacute; Mitte Schumannstra&szlig;e 20/21 D-10117 Berlin  相似文献   
23.
小梁切除加脉络膜上腔引流术治疗青光眼   总被引:1,自引:2,他引:1  
目的:对传统的青光眼手术与小梁切除 脉络膜上腔引流术对青光眼的疗效进行对比分析。以期了解小梁切除 脉络膜上腔引流术式治疗青光眼的优缺点,并做出评价。方法:将过去4a内在我院接受传统手术与小梁切除 脉络膜上腔引流术的青光眼患者按术式的不同分为2组,其中,接受传统术式组63例(122眼),接受新术式者16例(16眼),作者将各术式治疗后的眼压差值、结膜滤过泡及前房形成的时间,并发症等几个方面进行比较。结果:两组比较的结果表明:小梁切除 脉络膜上腔引流术在治疗青光眼降低眼压方面有明显优势,差异有显著性。而在结膜滤过泡形成及前房形成时间及并发症减少方面无显著性。结论:小梁切除 脉络膜上腔引流术在治疗青光眼方面有较大的优越性。  相似文献   
24.
晶状体囊染色技术在超声乳化术中的应用   总被引:2,自引:1,他引:2  
目的探讨晶状体囊染色技术在晶状体超声乳化术中应用的有效性和安全性.方法在难以看清晶状体前囊的65例(83眼)老年性白内障的手术过程中,使用囊染色剂vision blue(0.6 g·L-1的苔盼蓝缓冲溶液)气泡下染色法进行前囊染色,观察术中和术后情况.结果囊染色剂vision blue对晶状体前囊有较好的染色效果,可使手术操作变得安全易行,术中术后无不良反应.结论囊染色剂vision blue在晶状体超声乳化术中对晶状体前囊染色的应用是有效的和安全的.  相似文献   
25.
异丙酚静脉麻醉在食管贲门狭窄扩张治疗中的应用研究   总被引:1,自引:0,他引:1  
目的 研究应用异丙酚静脉麻醉在食管贲门狭窄扩张治疗中的可行性和安全性。方法 将食管狭窄病人 80例随机分为观察组 (A组 ) 40例和对照组 (B组 ) 40例 ,观察组给予异丙酚静脉麻醉后再行扩张等治疗 ,对照组则不予静脉麻醉而行常规操作 ,比较两组扩张治疗中病人的反应和感受、操作时间及观察组在治疗前、中、后血压、心率和血氧饱和度的变化。结果 观察组病人满意度 95% ,而对照组为 18% (P <0 0 1) ,观察组病人流涎、恶心呕吐和躁动的发生率明显低于对照组 (P <0 0 1) ,观察组平均操作时间相对较短 ,心率、血压 (收缩压和舒张压 )、血氧饱和度治疗前、中、后无明显差别。结论 在食管贲门狭窄扩张治疗中应用异丙酚静脉麻醉是安全有效的 ,且可缩短操作时间 ,减少不良反应 ,提高病人的依从性  相似文献   
26.
可生物降解的聚乳酸羟基乙酸牙周缓释凝胶的研究   总被引:3,自引:1,他引:3  
目的采用聚乳酸羟基乙酸(PLGA)研制替硝唑牙周缓释凝胶。方法根据聚合物的分子量、浓度、载药量和增塑剂等因素来优选最佳配方。结果聚合物溶液中N-甲基-2-吡咯烷酮(NMP)P、EG400、PLGA(75∶25)的最佳比例为65∶5∶30,5%替硝唑与聚合物溶液均匀混合即得凝胶。凝胶必须在室温下避光保存。结论该凝胶缓释时间长达7d,用于牙周炎的治疗有效。  相似文献   
27.
BackgroundCardiometabolic risk has been shown to be inversely associated with cardiorespiratory fitness (CRF) and positively associated with body mass index (BMI).ObjectiveOur objective was to analyze the association of cardiometabolic risk factors with combined BMI and CRF in schoolchildren from a city in southern Brazil.MethodsCross-sectional study with a sample of 1252 schoolchildren aged seven to 17 years. Total cholesterol (TC), HDL-c, LDL-c, triglycerides (TG), systolic (SBP) and diastolic blood pressure (DBP) were evaluated. CRF and BMI were grouped into one variable and the schoolchildren were classified as eutrophic/fit, eutrophic/unfit, overweight-obese/fit, and overweight-obese/unfit. Crude and adjusted analyzes were performed using Poisson Regression and an alpha of 0.05 was adopted.ResultsOverweight-obese and fit schoolchildren showed a prevalence ratio (PR) of 1.50 (1.04 – 2.16) for altered TG, 3.05 (2.05 – 4.54) for elevated SBP, and 2.70 (1.87 – 3.88) for elevated DBP. Overweight-obese and unfit schoolchildren showed a PR for high TC of 1.24 (1.11 – 1.39) and 1.51(1.11 – 2.04) for low HDL levels. In addition, they had a risk of 2.07 (1.60 – 2.69) for altered TG, 3.36 (2.31 – 4.60) for elevated SBP and 2.42 (1.76 – 3.32) for altered DBP.ConclusionBMI played a central role in the association with risk and CRF was shown to attenuate the association between risk factors and obesity. Overweight-obese children and adolescents had a higher cardiometabolic risk, but the effect size was larger among the unfit.  相似文献   
28.
The syndrome of Leser‐Tr�e9;lat (LT) is a rare paraneoplastic syndrome. However, patients presenting with the sign of Leser‐Tr�e9;lat should be considered to harbor an occult malignancy or a progressive tumor disease until “proven” otherwise. Herein, we present two cases of non‐small‐cell lung carcinoma associated with LT syndrome.  相似文献   
29.
BackgroundCatheter ablation is a well-established therapy for rhythm control in patients who are refractory or intolerant to anti-arrhythmic drugs (AAD). Less is known about the efficacy of catheter ablation compared with AAD as a first-line strategy for rhythm control in atrial fibrillation (AF).ObjectivesWe aimed to perform a systematic review and meta-analysis of catheter ablation vs. AAD in patients na�ef;ve to prior rhythm control therapies.MethodsPubMed, EMBASE, and Cochrane databases were searched for randomized controlled trials that compared catheter ablation to AAD for initial rhythm control in symptomatic AF and reported the outcomes of (1) recurrent atrial tachyarrhythmias (ATs); (2) symptomatic AF; (3) hospitalizations; and (4) symptomatic bradycardia. Heterogeneity was examined with I2statistics. P values of < 0.05 were considered statistically significant.ResultsWe included five trials with 994 patients, of whom 502 (50.5%) underwent catheter ablation. Mean follow-up ranged from one to five years. Recurrences of AT (OR 0.36; 95% CI 0.25-0.52; p<0.001) and symptomatic AF (OR 0.32; 95% CI 0.18-0.57; p<0.001), and hospitalizations (OR 0.25; 95% CI 0.15-0.42; p<0.001) were significantly less frequent in patients treated with catheter ablation compared with AAD. Symptomatic bradycardia was not significantly different between groups (OR 0.55; 95% CI 0.18-1.65; p=0.28). Significant pericardial effusions or tamponade occurred in eight of 464 (1.7%) patients in the catheter ablation group.ConclusionThese findings suggest that catheter ablation has superior efficacy to AAD as an initial rhythm control strategy in patients with symptomatic AF.  相似文献   
30.
Vitamin D deficiency (VitDD) rickets and other manifestations of severe VitDD, such as cardiomyopathy and hypocalcemic seizures, continue to be diagnosed in Canada. Breastfed Indigenous infants, particularly those living in northern communities, are disproportionately impacted, although formula-fed infants are not exempt in cases where the mother’s vitamin D status is critically low. This statement deals with the prevention of rickets and hypocalcemia due to VitDD for Indigenous children, and revises an earlier document from the Canadian Paediatric Society. An assessment of the risk for VitDD is recommended for each maternal-infant dyad because of the link between maternal and infant VitDD. Along with supports for enhanced adherence, additional VitD supplementation is recommended for prenatal women and infants deemed at high risk and, in certain situations, intermittent higher dose supplementation may be required. Food insecurity can also contribute to rickets, so advocacy is required to prevent VitDD rickets in Indigenous children.  相似文献   
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