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51.
目的:比较两种不同血压波动测定方法测定的血压波动与颈动脉斑块发生的关系。方法:以1456名患有动脉硬化老年男性患者为研究对象,监测患者24 h动态血压,根据有无颈动脉斑块将入选患者分为2组:颈动脉斑块组(n=1012)和无颈动脉斑块组(n=444),分别采用经典的标准差方法(SD法)和个体血压波动测定方法(个体法)分别测定每位患者的血压波动,回顾性分析这两种方法测定的血压波动与颈动脉斑块形成的关联性。结果:SD法测定颈动脉斑块组24 h收缩期血压波动(SBPV)、白天SBPV、夜间SBPV以及24 h舒张期血压波动(DBPV)水平均明显高于无颈动脉斑块组(P0.05);而白天和夜间DBPV差异无统计学意义。个体法测定颈动脉斑块组24 h SBPV、白天SBPV、24 h DBPV以及白天DBPV水平较无颈动脉斑块组均明显升高(P0.05);夜间SBPV和夜间DBPV差异无统计学意义(P0.05)。比较颈动脉斑块组SBPV值出现次数,SD法测定SBPV最多的是10-15 mmHg(n=541),其次是大于15 mmHg(n=399);个体法测定颈动脉斑块组SBPV值出现次数最多的是0-8 mmHg(n=490),其次是8-10 mmHg(n=350)。结论:在老年男性动脉硬化相关疾病患者中,血压波动与颈动脉斑块的形成有着密切的关系,两种方法均可测定血压波动,但以个体血压波动测定方法更加敏感。  相似文献   
52.
目的:探究视网膜静脉阻塞与颈动脉狭窄的相关性研究,并为其临床检测、治疗与预后提供参考。方法:选择我院55例视网膜静脉阻塞患者(55只眼)为研究组,对其裸眼视力、矫正视力、眼压、眼底血管荧光造影(FFA)等检查资料进行分析,并进行多普勒彩超检查,记录其颈动脉狭窄情况,并对两种疾病之间的关系进行分析。同时选取55例健康人作为对照组。结果:研究组55例患者确诊为视网膜静脉阻塞(RVO),多普勒结果显示患者患侧与健侧劲动脉血流动力学各项差异不明显(P0.05);其IMT值较之对照组显著增高(P0.05);其PSV与EDV值有所降低,差异具有统计学意义(P0.05)。结论:视网膜静脉阻塞患者大多存在颈动脉狭窄,因此检测颈动脉血流动力学对于诊断与预防视网膜静脉阻塞有着重要作用。  相似文献   
53.
目的:探讨阿托伐他汀钙联合阿司匹林对短暂性脑缺血发作的治疗疗效及其对颈动脉粥样硬化斑块和血脂水平的影响。方法:选择我院80例短暂性脑缺血发作患者,按入院顺序随机平均分为两组,研究组40例患者给予阿托伐他汀钙联合阿司匹林治疗,对照组40例患者仅使用阿司匹林治疗。比较两组患者治疗后的治疗有效率,6个月后分别对两组患者颈动脉粥样硬化斑块及血脂水平进行检测。结果:研究组患者治疗总有效率为92.5%,明显高于对照组75%,比较差异具有统计学意义(P0.05);治疗6个月后研究组患者IMT及斑块面积较治疗前明显降低,且降低程度明显高于对照组,比较差异具有统计学意义(P0.05);研究组血清中LDL、TC、TG水平较治疗前显著下降,且下降程度明显高于对照组,同时HDL水平显著上升,而上升程度也明显高于对照组,比较差异具有统计学意义(P0.05)。结论:阿托伐他汀钙联合阿司匹林对短暂性脑缺血发作的治疗疗效显著,可明显减轻或消除颈动脉粥样硬化斑块并明显降低血脂水平,值得推广应用。  相似文献   
54.
摘要 目的:探究象皮生肌膏对肛瘘切除术后大鼠创面的治疗作用及其与PI3K/Akt/mTOR信号通路的相关性。方法:将SD雄性大鼠随机分为假手术组、模型组、象皮生肌膏组、湿润烧伤膏组,共4组,每组10只。4组均采用0号钢丝制造肛瘘模型,造模成功后,除假手术组外,均在麻醉下行肛瘘切除术,创面保持开放,使之形成"开放、渗血、渗液、有脓性分泌物"的感染性肛瘘术后创面,假手术组保留瘘管,不予换药,模型组予以生理盐水冲洗、络合碘消毒后不予换药,治疗组分别予以相应药物进行创面换药,共10天。10天后采用常规面积检测法比较模型组、象皮生肌膏组、湿润烧伤膏组大鼠肛瘘术后创面的创面愈合率及创面肉芽组织覆盖率;HE染色观察各组大鼠肛周组织病理情况;ELISA检测各组大鼠血清中bFGF、EGF、VEGF的表达水平,WB检测比较各组大鼠肛周肉芽组织中PI3K、Akt、mTOR、p70 S6K、p-PI3K(S473)、p-AKT(S473)、p-mTOR(Ser2448)、p-p70 S6K的蛋白表达水平。结果:与模型组比较,治疗第3、7、10天象皮生肌膏组和湿润烧伤膏组的创面愈合率及创面肉芽组织填充率显著升高(P<0.01)。病理切片显示,假手术组炎性细胞浸润较少,其余各组均可见不同程度的炎性细胞浸润,且创面区可见不同程度炎性修复型肉芽组织增生、胶原纤维新生及血管扩张;其中模型组病理切片显示大量炎性细胞浸润,血管扩张明显,并有明显的血管出血;象皮生肌膏组病理切片显示炎性细胞较少,成纤维细胞成熟且分布整齐,真皮层内胶原纤维丰富且排列整齐,可见血管新生,无明显血管扩张及出血;湿润烧伤膏组病理切片显示少量炎性细胞浸润及血管扩张,真皮层内可见成纤维细胞生成。ELISA检测结果显示,与假手术组比较,模型组血清中bFGF、EGF、VEGF的含量显著降低(P<0.01);与模型组比较,象皮生肌膏组血清中bFGF、EGF、VEGF的含量显著升高(P<0.01),湿润烧伤膏组大鼠血清中EGF、VEGF的含量显著升高(P<0.01)。WB检测结果显示,与假手术组比较,模型组肛周组织中p-PI3K、p-Akt 、p-mTOR、p-p70 S6K蛋白表达显著降低(P<0.01);与模型组比较,象皮生肌膏组肛周组织中p-PI3K、p-Akt 、p-mTOR、p-p70 S6K蛋白表达显著升高(P<0.05)。结论:象皮生肌膏能有效促进肛瘘术后创面修复,减轻肛瘘术后创面炎症反应,促进创面肉芽生长,其促愈机制可能与PI3K/Akt/mTOR信号通路相关蛋白表达有关,其通过上调PI3K/Akt/mTOR信号通路相关蛋白激活PI3K/Akt/mTOR信号通路,进而加快创面修复进程。  相似文献   
55.
The arteriovenous fistula (AVF) still suffers from a high number of failures caused by insufficient remodeling and intimal hyperplasia from which the exact pathophysiology remains unknown. In order to unravel the pathophysiology a murine model of AVF-failure was developed in which the configuration of the anastomosis resembles the preferred situation in the clinical setting. A model was described in which an AVF is created by connecting the venous end of the branch of the external jugular vein to the side of the common carotid artery using interrupted sutures. At a histological level, we observed progressive stenotic intimal lesions in the venous outflow tract that is also seen in failed human AVFs. Although this procedure can be technically challenging due to the small dimensions of the animal, we were able to achieve a surgical success rate of 97% after sufficient training. The key advantage of a murine model is the availability of transgenic animals. In view of the different proposed mechanisms that are responsible for AVF failure, disabling genes that might play a role in vascular remodeling can help us to unravel the complex pathophysiology of AVF failure.  相似文献   
56.
Summary Developmental patterns of immunoreactivity for serotonin and neuropeptide Y were investigated immunohistochemically in the carotid body and glomus cells in the wall of the common carotid artery and around its branches of chickens at various developmental ages. The development of peptidergic nerve fibers was also studied. Serotonin immunoreactivity began to appear in the glomus cells of the carotid body and around arteries at 10 days of incubation and became very intense from 12 days onwards. Neuropeptide Y immunoreactivity also appeared in these cells at 10 days, became intense at 14 days, and was sustained until 20 days. After hatching, neuropeptide Y immunoreactivity in the carotid body rapidly decreased with age and almost cisappeared at posnatal day 10. However, it persisted for life in the glomus cells distributed in the wall of the common carotid artery. Substance P- and calcitonin gene-related peptide (CGRP)-immunoreactive fibers first penetrated into the carotid body parenchyma at 12 days of incubation. These peptidergic nerve fibers in the carotid body and glomus cell groups in and around arteries gradually increased with age, and approached the adult state at 18 days of incubation. Only a few galanin-and vasoactive intestinal peptide (VIP)-immunoreactive fibers were observed in the late embryonic carotid bodies. They rapidly developed after hatching and reached adult numbers at postnatal day 10. During late embryonic and neonatal development, considerable numbers of met-enkephalin-immunoreactive fibers were detected in the connective tissue encircling the carotid body.  相似文献   
57.
Summary Rat carotid bodies were studied electron microscopically after short-term severe hypovolaemia, which is known to induce a marked chemoreceptor activation in the carotid body. Altogether 84 nerve-endings in the hypovolaemic rats' carotid bodies and 91 nerve-endings in the control carotid bodies were investigated. An increased accumulation of the glomus cell granular vesicles near the synaptic specializations of the nerve-endings was observed after hypovolaemia. Moreover, a statistically significant increase in the contacts between the nerve-ending synaptic specializations and the glomus cell granular vesicles was observed after hypovolaemia. A suggestion was made that the glomus cells might act as modulating, probably inhibitory, interneurones, whose catecholamines are responsible for the inhibition.The authors are greatly indebted to lecturer Pekka Korkala Ph.L. from the Department of Psychology for his skilful statistical analysis of the results.  相似文献   
58.
To determine the importance of dopamine and noradrenaline as neurotransmitters during chemoreception in the cat carotid body we investigated the contents of both compounds as well as the activity of dopamine-beta-hydroxylase (DBH) under different arterial PO2 and PCO2 conditions. The superior cervical ganglion was used as a control organ. In the carotid body and the ganglion an inverse relationship exists between the catecholamine content and the DBH activity. The carotid body has a high catecholamine content with a low DBH activity whereas the superior cervical ganglion has a low catecholamine content and high DBH activity. Hypercapnia did not produce any significant change in the catecholamine content or in the DBH content of the carotid body. However, in comparison with hyperoxia, hypoxia produced a significant change (p less than 0.05) in the noradrenaline content without changing the DBH activity. The dopamine content under these conditions did not change significantly. The results may indicate that the high catecholamine content of the carotid body is the result of a high retention and/or low rate of degradation rather than of a high rate of synthesis.  相似文献   
59.
Summary The postulated mechanisms for hypoxic and acidic chemotransduction by type I cells that we have described here are summarized in the diagrams of Fig. 4. Most if not all of these require more complete evaluation and, as we have described, there are obvious points of contention that need to be resolved. Nevertheless, it is apparent that studies of isolated type I cell preparations carried out over the last six years have provided significant advancements in our understanding of chemotransduction in the type I cell. Only when the functioning of these cells has been fully described can we hope to understand the mechanisms underlying the responses of the intact organ to chemostimuli.Many of the findings reported here, including those to which the authors have contributed, were supported by The Wellcome Trust. We are also grateful to colleagues for allowing us to reproduce parts of their data.  相似文献   
60.
Zusammenfassung Die Glomera carotica von 12 Kaninchen wurden nach viertägiger Applikation von Reserpin (2 mg/kg KG; i.p.) (I), Parachlorphenylalanin-methylester-hydrochlorid (PCPA; 100 mg/kg KG; i.p.) (II) und physiologischer NaCl-Lösung (III) mit der Falckschen Fluoreszenzmethode aufgearbeitet und cytospektrofluorometrisch (Mikrospektrograph Leitz) ausgewertet.An Hand der Fluoreszenzspektren der spezifischen Glomuszellen (Typ I) ließ sich eine Depletion der Catecholamine und des Serotonins verfolgen: hiernach senkt PCPA vor allem das Serotonin, Reserpin hingegen die Catechol- und Indolamine in etwa gleichem Umfang.Durch Zerlegung einiger Gesamtspektren in die Anteile für Catecholamine und das Serotonin mit Hilfe eines Iterationsverfahrens der nichtlinearen Regression konnte gezeigt werden, daß nur eine geringfügige Beeinflussung der Catecholamin-Peakhöhe durch das Serotonin vorliegt. Über die Messung der Peakhöhe im Catecholaminbereich der Gesamtspektren konnte daher die Reduktion der Catecholamine auf 64±22% durch PCPA und auf 13±4% durch Reserpin statistisch gesichert werden.Die Befunde werden im Zusammenhang mit den möglichen Wirkungsmechanismen der applizierten Substanzen diskutiert. Eine ausführliche tabellarische Zusammenstellung der bisherigen Angaben über Gehalt und Zusammensetzung der biogenen Amine des Glomus caroticum ergänzt diese Diskussion.
Microspectrofluorometric investigation of biogenic amines in the rabbit glomus caroticum after reserpine and PCPA treatment
Summary After the administration for 4 days of (I) reserpine (2 mg/kg body weight daily, i.p.), (II) p-chlorophenylalanine-methylester-hydrochloride (PCPA; 100 mg/kg body weight daily; i.p.) and III physiological NaCl solution, the carotid bodies of 12 rabbits were examined using Falck's fluorescence technique and evaluated cytospectrofluorometrically. Fluorescence spectra of the type I specific glomus cells revealed that a depletion of catecholamines and serotonin took place: PCPA lowered mainly serotonin, whereas reserpine depleted catechol- and indolamines about equally.It was shown by splitting of a few combined spectra with an iteration procedure of nonlinear regression, that serotonin affected slightly the height of the catecholamine peak. Thus, measuring the peak height in the catecholamine region of the total spectrum, the reduction of catecholamines to 64±22% by PCPA and to 13±4% by reserpine was statistically significant.These data are discussed in relation to possible mechanisms of action of the test substances and related to the content and nature of the biogenic amines in the carotid body.
Für technische Hilfe danken wir Fräulein B. Remki und Frau K. Wilp.  相似文献   
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