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目的研究葛根素联合复方樟柳碱注射液对眼底病患者的治疗效果及对血液流变学指标的影响。方法选择2013年4月至2014年4月在绵阳市第三人民医院眼科进行眼底病治疗的患者100例,并按入院顺序抽签随机分为观察组和对照组,各50例。对照组进行葛根素常规治疗(葛根素注射液0.4 g加入生理盐水250 m L中静脉滴注,每日1次,1个疗程14 d,1个疗程后停药3 d,再进行下一疗程),观察组在此基础上联合复方樟柳碱注射液进行治疗(采用复方樟柳碱2 m L在患者颞浅动脉旁行皮下注射,每日1次,1个疗程14 d,完成1个疗程后停药3 d,再换肾俞穴进行注射,1个疗程后停药3 d,再进行第一个疗程的用药)。3个疗程后,比较两组患者治疗前后血液流变学的变化、术后复发率和不良反应情况及患者的治疗效果。结果治疗后,观察组全血黏度为(4.82±0.41)m Pa·s明显低于对照组的(5.56±0.39)m Pa·s,红细胞聚集指数(3.80±0.41)明显低于对照组(4.77±0.55),纤维蛋白原(4.20±0.24)g/L明显低于对照组(5.25±0.43)g/L,差异均有统计学意义(t=9.247,9.998,15.077,P<0.01);观察组患者治疗后复发率为2.0%(1/50),不良反应的总发生率为4.0%(2/50),分别低于对照组14.0%(7/50)和18.0%(9/50)(P<0.01);观察组患者的总有效率为98.0%(49/50),显著高于对照组的82.0%(41/50)(P<0.05)。结论葛根素和复方樟柳碱注射液联合治疗眼底病患者,可改善患者血液流变学,并提高临床治疗效果。 相似文献
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目的建立中国成年患者的替考拉宁(teicoplanin,TEC)群体药动学(population pharmacokinetics,PPK)模型,考察TEC药动学参数的影响因素。方法前瞻性收集139例革兰阳性球菌感染患者静脉注射TEC后的222份常规监测血药浓度和相关信息,采用一级消除的一室模型进行数据拟合,并应用非线性混合效应模型(nonlinear mixed effect model,NONMEM)程序建立PPK模型。采用Bootstrap、正态预测分布误差法(normalized predictive distribution error,NPDE)进行最终模型评价。利用蒙特卡洛模拟法对给药方案进行优化。结果确定了肌酐清除率(creatinine clearance,CLcr)、白蛋白(albumin,ALB)为影响TEC清除率的主要因素。最终模型为:CL(L·h^-1)=1.24×(CLcr/77)0.564×31/ALB;V(L)=69.2。验证表明,模型稳定、有效,且有较好的预测效能。对于不同ALB和CLcr的多数患者起始负荷剂量400 mg/q12h,iv,3次,维持剂量400~800 mg·d^-1的给药方案可达有效治疗谷浓度。严重感染者需调整负荷剂量至800 mg/q12h,iv,3次,维持剂量400~800 mg·d^-1的给药方案来确保血药浓度达到15 mg·L^-1以上。结论本实验报道了CLcr、ALB对TEC清除率有显著影响,所建模型对TEC在中国成人患者中实现个体化给药具有重要应用价值。 相似文献
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线粒体脑肌病属于罕见性母系遗传病,本文回顾性分析了1家4例高乳酸血症-卒中样发作综合征(MELAS)型线粒体脑肌病患者,其主要表现为卒中样发作、头痛、癫痫、高乳酸血症、肌肉不耐受疲劳、高级智能下降、听力下降和身材矮小等,结合特征性影像学变化、基因检测及肌肉活检明确诊断,并结合文献对只有女儿能将其线粒体DNA(mt-DNA)传递给下一代的母系遗传MELAS型线粒体脑肌病临床特点进行了总结分析,旨在帮助临床认识此病,进一步提高MELAS型线粒体脑肌病的临床诊断率。 相似文献
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Se-Jin Lee Adam Lehar Yewei Liu Chi Hai Ly Quynh-Mai Pham Michael Michaud Renata Rydzik Daniel W. Youngstrom Michael M. Shen Vesa Kaartinen Emily L. Germain-Lee Thomas A. Rando 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(49):30907
Myostatin (MSTN) is a transforming growth factor-β (TGF-β) family member that normally acts to limit muscle growth. The function of MSTN is partially redundant with that of another TGF-β family member, activin A. MSTN and activin A are capable of signaling through a complex of type II and type I receptors. Here, we investigated the roles of two type II receptors (ACVR2 and ACVR2B) and two type I receptors (ALK4 and ALK5) in the regulation of muscle mass by these ligands by genetically targeting these receptors either alone or in combination specifically in myofibers in mice. We show that targeting signaling in myofibers is sufficient to cause significant increases in muscle mass, showing that myofibers are the direct target for signaling by these ligands in the regulation of muscle growth. Moreover, we show that there is functional redundancy between the two type II receptors as well as between the two type I receptors and that all four type II/type I receptor combinations are utilized in vivo. Targeting signaling specifically in myofibers also led to reductions in overall body fat content and improved glucose metabolism in mice fed either regular chow or a high-fat diet, demonstrating that these metabolic effects are the result of enhanced muscling. We observed no effect, however, on either bone density or muscle regeneration in mice in which signaling was targeted in myofibers. The latter finding implies that MSTN likely signals to other cells, such as satellite cells, in addition to myofibers to regulate muscle homeostasis.Myostatin (MSTN) is a secreted signaling molecule that normally acts to limit skeletal muscle growth (for review, see ref. 1). Mice lacking MSTN exhibit dramatic increases in muscle mass throughout the body, with individual muscles growing to about twice the normal size (2). MSTN appears to play two distinct roles in regulating muscle size, one to regulate the number of muscle fibers that are formed during development and a second to regulate the growth of those fibers postnatally. The sequence of MSTN has been highly conserved through evolution, with the mature MSTN peptide being identical in species as divergent as humans and turkeys (3). The function of MSTN has also been conserved, and targeted or naturally occurring mutations in MSTN have been shown to cause increased muscling in numerous species, including cattle (3–5), sheep (6), dogs (7), rabbits (8), rats (9), swine (10), goats (11), and humans (12). Numerous pharmaceutical and biotechnology companies have developed biologic agents capable of blocking MSTN activity, and these have been tested in clinical trials for a wide range of indications, including Duchenne and facioscapulohumeral muscular dystrophy, inclusion body myositis, muscle atrophy following falls and hip fracture surgery, age-related sarcopenia, Charcot–Marie–Tooth disease, and cachexia due to chronic obstructive pulmonary disease, end-stage kidney disease, and cancer.The finding that certain inhibitors of MSTN signaling can increase muscle mass even in Mstn−/− mice revealed that the function of MSTN as a negative regulator of muscle mass is partially redundant with at least one other TGF-β family member (13, 14), and subsequent studies have identified activin A as one of these cooperating ligands (15, 16). MSTN and activin A share many key regulatory and signaling components. For example, the activities of both MSTN and activin A can be modulated extracellularly by naturally occurring inhibitory binding proteins, including follistatin (17, 18) and the follistatin-related protein, FSTL-3 or FLRG (19, 20). Moreover, MSTN and activin A also appear to share receptor components. Based on in vitro studies, MSTN is capable of binding initially to the activin type II receptors, ACVR2 and ACVR2B (also called ActRIIA and ActRIIB) (18) followed by engagement of the type I receptors, ALK4 and ALK5 (21). In previous studies, we presented genetic evidence supporting a role for both ACVR2 and ACVR2B in mediating MSTN signaling and regulating muscle mass in vivo. Specifically, we showed that mice expressing a truncated, dominant-negative form of ACVR2B in skeletal muscle (18) or carrying deletion mutations in Acvr2 and/or Acvr2b (13) have significantly increased muscle mass. One limitation of the latter study, however, was that we could not examine the consequence of complete loss of both receptors using the deletion alleles, as double homozygous mutants die early during embryogenesis (22). Moreover, the roles that the two type I receptors, ALK4 and ALK5, play in regulating MSTN and activin A signaling in muscle in vivo have not yet been documented using genetic approaches. Here, we present the results of studies in which we used floxed alleles for each of the type II and type I receptor genes in order to target these receptors alone and in combination in muscle fibers. We show that these receptors are functionally redundant and that signaling through each of these receptors contributes to the overall control of muscle mass. 相似文献
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失眠是由各种原因导致的入睡困难和(或)睡眠维持困难的睡眠障碍,主要特征是睡眠感不满意,属于中医学"不得眠""不寐"范畴。传统多从心、肝、胆、脾、胃、肾论治该病,杜元灏教授认为脏腑机能失调,气血不和,阳不能入阴,阴不能涵阳,神不守舍而致失眠。重视"脑为元神之腑"的理论,且因督脉入络脑,夹脊穴为五脏六腑之气转输、流注之处,杜教授多强调从脑、督脉以及夹脊穴论治失眠,为针刺治疗失眠提供新思路。 相似文献
8.
目的探讨胼胝体梗死的临床表现、病因及鉴别诊断特点。方法对2005年7月收治的1例53岁男性胼胝体梗死患者的临床表现、影像学特点、病因机制及其治疗过程进行回顾分析。结果临床主要表现为发作性黑蒙、言语不利,既往有高血压、糖尿病、脑梗死、吸烟、饮酒史,体格检查以失用为主要表现。头部MRI检查可见左侧脑室旁、胼胝体梗死,右侧基底节、脑桥陈旧性腔隙性梗死;脑血管造影检查显示为多发性血管狭窄,其中以左侧大脑中动脉、右侧颈内动脉及基底动脉最为严重。经颈内动脉内膜剥离术及颈内动脉支架植入术治疗,临床症状缓解。结论失用可以是胼胝体梗死的主要表现,其病因是在脑动脉粥样硬化基础上的血流动力学改变,患者预后良好。 相似文献
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Fas/FasL在各阶段婴幼儿血管瘤中的表达及意义 总被引:15,自引:0,他引:15
目的 检测Fas/FasL在各阶段婴幼儿血管瘤组织中的表达,探讨Fas/FasL在婴幼儿血管瘤细胞凋亡中的作用。方法 应用EnVision法免疫组化染色和RT-PCR检测Fas/FasL蛋白及mRNA在各阶段血管瘤组织中的表达。结果 ①增生早期和增生中期,部分血管瘤细胞表达Fas;增生晚期,阳性细胞明显增多,Fas mRNA表达最强;消退早期,仍有少量微血管内皮细胞表达Fas,之后Fas表达迅速减弱。②最早期细胞团中没有FasL(+)细胞;增生中期,血管瘤组织中出现少量FasL(+)细胞;增生晚期FasL(+)细胞显著增多,FasL mRNA表达最强;消退早期之后,FasL(+)细胞迅速减少以至消失。结论 Fas/FasL与婴幼儿血管瘤演变过程有密切联系,Fas/FasL介导的血管瘤细胞凋亡可能是婴幼儿血管瘤自行消退的重要原因。 相似文献
10.
64层CT下肢动脉成像技术研究 总被引:6,自引:0,他引:6
目的探讨64层CT下肢动脉成像强化质量的对比剂注射方式。方法前瞻性地选择60例疑诊下肢动脉病变的病人,利用64层螺旋CT行下肢动脉CT血管成像。采用不同的扫描和重建参数,应用370mgI/100ml浓度的对比剂100ml团注或采用先70ml的对比剂后50ml的0.9%生理盐水用双筒高压注射器分别以4.0ml/s的注射速度团注入肘静脉,应用对比剂追踪触发扫描方式待腹主动脉CT阈值达120HU时延迟7s开始扫描;利用MIP和VR方式重建CTA图像;对比不同参数和不同对比剂应用方式的CT血管成像图像质量。结果最佳的扫描与重建参数为准直64×0.6mm,螺距1.5,层厚1.0,重建间隔50%;最佳的对比剂应用方式为(浓度为370mgI/100ml)对比剂70ml、生理盐水50ml以4.0ml/s注射速度按先后顺序团注。结论选择合适的准直、螺距以保证适当的扫描速度,选择合适的对比剂浓度、用量和注射速度以保证血管内足够的对比剂峰值浓度及峰值持续时间,此二者是64层CT下肢动脉成像成功的关键。 相似文献