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61.
PURPOSE: In bladder, sensory afferent nerve fibers contain the "sensory neuropeptides" substance P (SP), neurokinin A (NKA) and calcitonin gene-related peptide (CGRP), which interact with tachykinin NK-1 and NK-2 receptors and CGRP receptors, respectively. The purpose of this study was to examine the autoradiographic distribution of these three receptor types in the human bladder, to determine whether the anatomic location of the receptors was consistent with their known functional roles. MATERIALS AND METHODS: Specimens of urinary bladder from 9 patients (58-74 years) were obtained at cystectomy. Frozen sections of dome were labeled with [125I]-Bolton-Hunter [Sar9,Met(O2)11]-SP (NK-1 receptors), [125I]-[Lys5,Tyr(I2)7,MeLeu9,Nle10]-NKA(4-10) (NK-2 receptors) and [125I]-rat CGRP-I. Binding sites were visualized using emulsion autoradiography. RESULTS: NK-1 receptors were found over the endothelium of arterial blood vessels within the detrusor muscle and lamina propria, and over small vessels in the subepithelium. NK-2 receptors were seen over the detrusor muscle and very sparsely over blood vessels, whereas CGRP receptors were expressed densely over the smooth muscle layer of arteries and arterioles, and weakly over collecting venules. NK-1 and CGRP receptors were not observed over the detrusor muscle. CONCLUSIONS: Although the afferent nerves contain all three peptides, not all cell types express receptors for each peptide. The general distribution of receptors is in good agreement with the location of nerves, and with the known actions of SP and CGRP as vasodilator agents, and of NKA (but not SP or CGRP) in contracting the detrusor muscle.  相似文献   
62.
酸相关性疾病与幽门螺杆菌感染   总被引:2,自引:0,他引:2  
酸相关性疾病是指一类与胃酸攻击作用密切相关的上胃肠道疾病,包括器质性疾病和功能性疾病。根据病理生理机制的不同,酸相关性疾病主要分为胃食管反流病(GERD)、消化性溃疡病(PUD)和功能性消化不良(FD)三类。尽管目前对酸相关性疾病的发病机制已有了较深入的了解,但幽门螺杆菌(Hp)与其症状之间的关系仍不明确。现简要介绍幽门螺杆菌(Hp)感染在酸相关性疾病发生机制中的作用。  相似文献   
63.
Acute lung injury (ALI) or its more severe form, the acute respiratory distress syndrome (ARDS), is a common, devastating clinical syndrome that affects both medical and surgical patients. The most common cause of ALI is sepsis. There is now well-documented evidence that pulmonary inflammation contributes to the devel-opment of ALI. Despite significant advances in our un-derstanding of pathophysiology and technologies in the supportive management, mortality from ALI remains excessive. C…  相似文献   
64.
PURPOSE: Many cancer lines are methionine dependent and decrease proliferation when methionine supply is limited. Methylenetetrahydrofolate reductase (MTHFR) generates the folate derivative for homocysteine remethylation to methionine. We investigated the effect of antisense-mediated inhibition of MTHFR on survival of human cancer cells. EXPERIMENTAL DESIGN: We examined the in vitro and in vivo anticancer effects of a combination of MTHFR antisense and standard cytotoxic drugs. RESULTS: Specific antisense against MTHFR (EX5) showed significant inhibitory effects on growth of human colon, lung, breast, prostate, and neuroblastoma tumor cells in vitro compared with that of the control oligonucleotide. Cytotoxic drugs (5-fluorouracil, cisplatin, or paclitaxel) potentiated the effect of EX5. In vivo, antisense alone or in combination with cytotoxic drugs inhibited the growth of human colon and lung carcinoma xenografts. In comparison with control oligonucleotide, treatment with EX5 inhibited growth of colon tumors and lung tumors by 60% and 45%, respectively. EX5 with 5-fluorouracil decreased growth of colon tumors by an additional 30% compared with EX5 alone, and EX5 with cisplatin decreased growth of lung tumors by an additional 40% compared with cisplatin alone. Growth inhibition by EX5 was associated with decreased amounts of MTHFR protein and with increased amounts of an apoptosis marker. CONCLUSIONS: Our results confirm that MTHFR inhibition decreases tumor growth and suggest that inhibition of MTHFR by antisense or small molecules may be a novel anticancer approach.  相似文献   
65.

视网膜母细胞瘤(RB)是儿童最常见的眼内恶性肿瘤,多发于婴幼儿,可损害患儿视力、眼球,甚至危及生命。其发生和发展与基因组和表观基因组有很大关系,遗传性RB占所有病例的45%。RB的治疗和预后取决于疾病的初始阶段,当疾病被早期诊断和治疗时,存活率超过95%,当RB在晚期发生眼外播散时,存活率低于50%。因此RB的治疗重点是通过早期肿瘤的监测和预防挽救患儿生命,其次要目标是保存眼球,并最大水平地保留视力。对RB遗传学的研究有助于通过基因筛查、监测查找特异性靶点,对提高患儿的生存率、研究RB靶向治疗十分必要。  相似文献   

66.

目的:探讨儿童弱视临床特点和综合治疗效果。

方法:选取2015-07/2017-07我院确诊收治的弱视儿童393例715眼,建立弱视治疗档案,给予弱视综合疗法治疗,观察其治疗效果,并对其年龄、弱视类型、弱视程度、弱视注视性质和治疗依从性等影响疗效的临床特点进行分析。

结果:患儿393例715眼中,基本治愈者520眼(72.7%),进步者117眼(16.4%),无效者 78眼(10.9%),总有效率为89.1%。年龄、弱视类型、弱视程度、注视性质、治疗依从性等临床特点影响弱视治疗效果。

结论:儿童弱视的总体治疗效果较好。与患儿年龄、弱视类型、弱视程度、弱视注视性质和治疗依从性等临床特点关系密切。年龄偏大,弱视类型为屈光参差性弱视、斜视性弱视,弱视程度重、旁中心注视及依从性差的患儿治疗效果差。  相似文献   

67.
??Objective??To detect the level of fecal primary and secondary bile acids in infants with infantile cholestatic hepatopathy??ICH??and analyze its clinical value. Methods??Thirty infants with ICH were enrolled in this study??who were diagnosed with infantile cholestatic hepatopathy. Thirty infants with good health condition were enrolled as the healthy control group. The fecal samples were collected respectively in the preparatory treatment phase and treatment phase from infants with ICH and from the healthy infants. Bile acids were extracted from infants’ feces and were quantitatively analyzed by liquid chromatography-mass spectroscopy. Results??Among the fecal primary bile acids??the level of cholic acid??chenodeoxycholic and glycochenodeoxycholic acid both in the ICH preparatory treatment group and ICH treatment group was significantly lower than that in the healthy control group??P??0.016??.The level of fecal cholic acid and chenodeoxycholic acid of ICH treatment group was higher than in the ICH preparatory treatment group??P??0.016??. Among the fecal secondary bile acids??the level of lithocholic acid both in the ICH preparatory treatment group and ICH treatment group was significantly lower than that in the healthy control group??P??0.016????and the level of ursodeoxycholic acid in the ICH preparatory treatment group was lower than that in the ICH treatment group and healthy control group??P??0.016??. Conclusion??In infants with ICH, the changes of fecal primary bile acids and fecal secondary bile acids have their own characteristics at the early stage of treatment, which may be caused by the short-term treatment, the prognosis of the disease itself and the changes of intestinal function, including intestinal bacteria. Clinical attention should be paid to these changes.  相似文献   
68.
目的:评价泻肺利水法组方的心衰合剂对冠心病心力衰竭患者心衰超声指数的影响。方法:采用随机对照研究,选取2016年11月至2017年12月首都医科大学附属北京中医医院心血管科住院的冠心病HF、心功能NYHAⅢ-Ⅳ级患者60例,分为观察组和对照组,每组30例,观察组予西医常规治疗加用心衰合剂,对照组予西医常规治疗。疗程14 d。观察2组患者治疗前后中医证候积分和心衰超声指数积分。结果:治疗后2组患者中医证候积分均较治疗前显著改善(P0.05);组间比较,观察组较对照组改善更为显著(P0.05)。治疗后观察组的心室充盈、左室射血分数、肺动脉收缩压、房室重构、心衰超声指数积分均较治疗前改善(P0.05);治疗后对照组的心室充盈、左室射血分数、肺动脉收缩压、心衰超声指数积分较治疗前提高(P0.05)。治疗后观察组的瓣膜反流、肺动脉收缩压、心衰超声指数较对照组改善更明显(P0.05)。结论:在西医规范治疗基础上联合使用泻肺利水法组方的心衰合剂,可以改善冠心病心力衰竭患者的中医证候积分,改善患者的心衰超声指数。  相似文献   
69.
该文归纳出中药"显效理论",即中药通过"众多显效形式(显效型)的单靶点叠加作用、多靶点协同作用及毒性分散效应"发挥药效并削弱自身毒性。一味中药可含有约1 000种成分,一种成分口服进入体内后又可产生约100种代谢产物。无数化学成分及其无数体内代谢产物中的众多显效形式可共同发挥"集团军式作用"。在药物分子少、靶点分子多的情况下,中药不同种的显效型分子可相继与靶点分子结合,发生叠加作用,当"靶点充分占位"时药效始启动。既有浓度上的叠加作用又有时间段先后的叠加作用,这使得药效得以持久。显效型呈现药效叠加和毒性分散,源于不同显效形式分子结构之间药效基团相同而毒性基团不完全相同。"毒性分散效应"适于对无毒中药而不适于对有毒中药的解释。显效理论揭示中药可以众多化学成分及众多代谢产物参与发挥药效过程,包括叠加作用、协同作用及毒性分散效应,可有助于阐释和弘扬中药特色优势。今后需研究/确证的问题:中药药效物质基础及其作用机制是怎样构成的?多数中药为什么毒性小?体现中药特色优势的中药"显效理论"如何在新药研发中应用?  相似文献   
70.
目的探讨RNA技术分别沉默PI3K、AKT基因表达对人卵巢癌SKOV3细胞增殖与凋亡的比较,从而为卵巢癌的基因治疗提供有效的理论依据。方法体外合成PI3Kp110α、AKT序列特异性双链RNA(dsRNA),用lipofectamin2000转染人卵巢癌SKOV3细胞,采用MTT法检测细胞活性,流式细胞仪法检测细胞凋亡率。结果 MTT法检测siRNA-AKT组细胞增殖能力降低大于siRNA-PI3K组,差异有统计学意义(P<0.05),而流式细胞术检测siRNA-AKT组细胞凋亡率则高于siRNA-PI3K组,差异有统计学意义(P<0.05)。结论体外合成靶向AKT的siRNA更能有效地抑制人卵巢癌SKOV3细胞增殖及诱导细胞凋亡。PI3K通路并非AKT激活的唯一途径。  相似文献   
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