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101.
目的 探讨血清鸢尾素及脂联素(APN)水平与颈动脉粥样硬化的关系。方法 选取2020年1月—2022年1月海南省人民医院收治的124例H型高血压患者作为研究组,另选取同期来该院体检的健康者112例作为对照组。比较两组血清鸢尾素、APN水平,分析研究组颈动脉粥样硬化斑块形成的影响因素,采用受试者工作特征(ROC)曲线分析血清鸢尾素、APN水平预测颈动脉粥样硬化斑块形成的价值。结果 研究组血清鸢尾素、APN水平低于对照组(P <0.05)。斑块形成组与非斑块形成组性别、年龄、体重指数、吸烟史、饮酒史、收缩压、舒张压、血压控制良好、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、一氧化氮、尿酸、肌酐、内皮素水平比较,差异无统计学意义(P>0.05)。斑块形成组甘油三酯、同型半胱氨酸水平高于非斑块形成组(P <0.05),鸢尾素、APN水平低于非斑块形成组(P <0.05)。多因素一般Logistic回归分析结果显示:同型半胱氨酸水平[■=4.415(95%CI:1.817,10.730)]、血清鸢尾素水平[■=4.027(95%CI:1.657,9.787)]、AP... 相似文献
102.
In humans, electrical, bipolar, bilateral carotid sinus nerve stimulation (CSNS; impulse duration 0.35 ms) was applied, using frequencies between 10 and 110 Hz and voltages between individual thresholds and maximal amplitudes of stimulation. Ten anginal patients and two hypertensive patients were studied at an interval of up to 12 years after implantation of electrodes and a radiofrequency receiver for chronic therapeutic CSNS. In search of combinations of frequency and voltage of CSNS, eliciting largest ("optimal") depressor responses of blood pressure and heart rate in the individual patient, Rechenberg's evolution strategy was applied. This strategy simulates mutation and selection of biological evolution. In each patient and on each test stimulation, a value of quality was computed from actual heart rate and blood pressure values as a selection criterion for the strategy. Either responses to uninterrupted CSNS were investigated, while stimulation parameters were adjusted every 3 min, according to the strategy, or responses to 3 min of CSNS after a change in stimulation parameters were compared to intercalated 3-min control periods. In each patient, one or more combined settings of frequency and voltage elicited "optimal" responses. In principle, "optimal" CSNS frequencies ranged between 35 and 105 Hz with large interindividual differences. Due to chronic implantation of electrodes and technical features of radiofrequency transmitted stimulation energy, interindividually different voltages led to an optimal response to CSNS. Also according to the present results, the frequency of CSNS has to be determined individually. It is concluded that the evolution strategy was applied successfully, because voltage and frequency settings leading to "optimal" responses were found within 90-180 min, whereas intraindividual systematic investigations would not be feasible due to their necessarily very long duration. So far, only short-term responses have been evaluated. A broader use of the strategy in other applications is encouraged, as for example in pacemaker optimization and especially in functional electrostimulation. 相似文献
103.
目的 探讨颈动脉管、颈静脉窝与下鼓室的变异关系 ,为此区域手术提供可靠的解剖学资料。方法 在XSQ~Ⅱ型手术显微镜下解剖观察了 2 0 0例颞骨标本的下鼓室 ,并用游标卡尺对有关结构进行了测量。结果 下鼓室纵径 0 2 8mm ,横径为 0 85mm ,深为 1 2 8mm。下鼓室底与颈静脉窝相毗邻者见 93 0 %。当颈静脉窝大而上隆时 ,窝顶与鼓室间以薄骨板分隔 ,骨板最薄时仅为 0 2 0mm。颈静脉窝顶突入鼓室腔者占 1 2 5 % ,窝顶有骨质缺损者见 4 0 %。鼓室底与颈动脉管关系随颈动脉位置变化而异 ,有 6 8 0 %的标本颈动脉管位于岬下缘前 1 / 3区 ,4 0 %的标本颈动脉管占据范围达岬下缘后 1 / 3区。结论 下鼓室与颈静脉窝及颈动脉管存在着多种变异关系 ,下鼓室手术及静脉窝区手术应避免损伤颈静脉球及颈内动脉等结构 相似文献
104.
Arterial endothelial function in a porcine model of early stage atherosclerotic vascular disease 总被引:2,自引:0,他引:2
Turk JR Henderson KK Vanvickle GD Watkins J Laughlin MH 《International journal of experimental pathology》2005,86(5):335-345
Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the United States and is projected to become the leading cause of mortality in the world. Atherosclerosis is the most important single factor contributing to this disease burden. In this study, we characterize relationships between endothelial dysfunction and vascular disease in an animal model of diet-induced, early-stage atherosclerotic vascular disease. We tested the hypothesis that hypercholesterolaemia induces vascular disease and impairs endothelium-dependent relaxation (EDR) in conduit arteries of adult male Yucatan pigs. Pigs were fed a normal fat (NF) or high fat cholesterol (HFC) diet for 20-24 weeks. Results indicate that, while the HFC diet did not alter EDR in femoral or brachial arteries, EDR was significantly decreased in both carotid and coronary arteries. Sudanophilic fatty streaks were significantly present in the abdominal aorta and common carotid artery. Histopathology revealed increased intima-media thickness (IMT) and foam cell accumulation in Stary Stage I-III lesions in the abdominal aorta, common carotid artery and femoral arteries. In the coronary arteries, the accumulation of foam cells in Stary Stage I and II lesions resulted in a trend for increased IMT. There was no evidence of vascular disease in the brachial arteries. These results indicate that early stages of CVD (Stary Stage I-III) precede decreases in EDR induced by HFC diet, because femoral arteries exhibited foam cell accumulation and an increased IMT but no change in endothelial function. 相似文献
105.
Büyükmumcu M Ustün ME Seker M Karabulut AK Uysal YY 《Surgical and radiologic anatomy : SRA》2003,25(5-6):368-371
The possibility for maxillary artery (MA) to petrous internal carotid artery (ICA) bypass was investigated. Five adult cadavers were dissected bilaterally. After zygomatic arch osteotomy, the coronoid process was sectioned at its base. An extensive infratemporal craniotomy was performed at the level of foramina ovale, rotundum and spinosum. The petrous portion of the ICA was exposed by drilling away the floor of the middle fossa, posterior to the foramen ovale and medial to the foramen spinosum. The MA was identified medial to the infratemporal crest and was followed in the pterygopalatine fossa, then transected at the origin of the infraorbital artery. The MA graft was brought posteromedially to reach the petrous ICA. The mean caliber of the MA before the origin of the infraorbital artery was 2.54±0.31 mm, 2.76±0.14 mm at the site of anastomosis, and 3.46±0.32 mm after giving off the middle meningeal artery. The average length of the MA between the middle meningeal artery and the infraorbital artery was 43.4±2.35 mm, and up to the site of anastomosis was 37.64±1.68 mm. We conclude that the length and diameter of the MA are sufficient for a tension-free anastomosis between MA and petrous ICA, and such a procedure could be used in the treatment of patients with tumors of the infratemporal fossa invading the high cervical ICA.
Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Étude anatomique des possibilités de by-pass entre la partie pétreuse de l'artère carotide interne et l'artère maxillaire
Résumé La possibilité d'un by-pass entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne a été étudiée. Cinq cadavres adultes ont été disséqués des deux côtés. Après ostéotomie de l'arcade zygomatique, le processus coronoïde était sectionné à sa base. Une large craniotomie infra-temporale était effectuée au niveau du foramen ovale, du foramen rond et du foramen épineux. La partie pétreuse de l'artère carotide interne était exposée par fraisage du plancher de la fosse cérébrale moyenne, en arrière du foramen ovale et en dedans du foramen épineux. L'artère maxillaire était identifiée en dedans de la crête infra-temporale et suivie dans la fosse ptérygo-palatine, puis sectionnée à l'origine de l'artère infra-orbitaire. Le greffon d'artère maxillaire était transposé en dedans et en arrière pour atteindre la partie pétreuse de l'artère carotide interne. Le calibre moyen de l'artère maxillaire était de 2,54±0,31 mm à l'origine de l'artère infra-orbitaire, 2,76±0,14 mm au niveau de l'anastomose, et 3,46±0,32 mm après la naissance à l'artère méningée moyenne. La longueur moyenne de l'artère maxillaire entre l'artère méningée moyenne et l'artère infra-orbitaire était de 43,4±2,35 mm et au-delà du site d'anastomose était de 37,64±1,68 mm. Nous en avons conclu que la longueur et le diamètre de l'artère maxillaire était suffisant pour une anastomose sans tension entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne. Ainsi, une telle technique pourrait être utilisée pour le traitement de patients porteurs d'une tumeur de la fosse infra-temporale envahissant la partie cervicale haute de l'artère carotide interne.相似文献
106.
SUMMARY Epidemiological data indicate a link between sleep-disordered breathing and elevation of arterial pressure. Previous studies suggest increased activity of the sympathetic nervous system in patients with sleep apnoea. The response of muscle sympathetic nerve activity was further investigated in normal, awake subjects following exposure to 20 minutes of asphyxia. Sympathetic nerve traffic increased during exposure and remained elevated even after the return to room air breathing. These findings raise the possibility that this sustained elevation of sympathetic nerve traffic could play a role in the development of daytime hypertension in patients with sleep-disordered breathing. 相似文献
107.
目的探讨老年冠心病患者采用经皮冠状动脉介入(PCI)治疗的中短期疗效。方法对102例住院老年患者采用股动脉穿刺后,行球囊扩张,造影显示扩张满意后植入合适支架。术后随访6-32个月。结果102例患者术后临床症状均完全或基本完全缓解。本组患者有19例多支病变患者至少有一支慢性完全闭塞血管经努力而未能开通,无法植入支架。102例患者通过随访6-32个月,其中32例患者接受了冠脉造影复查,有17例患者分别于术后6个月至16个月又出现胸痛、胸闷症状。超声心动图检查射血分数(EF),心功能术后较术前明显改善,P<0.05。结论对冠状动脉慢性完全闭塞的老年患者,无论核素或超声检查是否存在存活心肌,均应尽量进行闭塞病变的介入治疗,以期改善患者的远期预后。 相似文献
108.
A mixture of experts network structure for modelling Doppler ultrasound blood flow signals 总被引:1,自引:0,他引:1
Mixture of experts (ME) is a modular neural network architecture for supervised learning. This paper illustrates the use of ME network structure to guide modelling Doppler ultrasound blood flow signals. Expectation-Maximization (EM) algorithm was used for training the ME so that the learning process is decoupled in a manner that fits well with the modular structure. The ophthalmic and internal carotid arterial Doppler signals were decomposed into time-frequency representations using discrete wavelet transform and statistical features were calculated to depict their distribution. The ME network structures were implemented for diagnosis of ophthalmic and internal carotid arterial disorders using the statistical features as inputs. To improve diagnostic accuracy, the outputs of expert networks were combined by a gating network simultaneously trained in order to stochastically select the expert that is performing the best at solving the problem. The ME network structure achieved accuracy rates which were higher than that of the stand-alone neural network models. 相似文献
109.
110.
药物洗脱支架用于急性心肌梗死的临床观察 总被引:1,自引:0,他引:1
目的评价药物涂层支架用于急性心肌梗死的安全性及临床疗效。方法34例发病1周以内的急性心肌梗死患者梗塞相关动脉机械性再灌注治疗时使用药物涂层支架,并于术后3~12个月进行门诊及电话随访,必要时复查冠状动脉造影,观察住院及随访期间心血管事件发生率(死亡、再发急性心肌梗死及血管重建术)。结果37枚药物涂层支架(CYPHER15枚,TAXUS22枚)植入34个梗塞相关动脉(其中3处病变各植入2枚支架),支架长度(22.7±9.0)mm,支架直径(3.1±0.3)mm;10例(29.4%)接受直接经皮冠状动脉介入治疗(PCI),3例(8.8%)为挽救性PCI。支架植入成功率100%。1例(2.9%)支架内急性血栓形成,行急诊血管重建术。平均随访间期(5.9±2.8)个月,2例(5.9%)于随访期间因再发原部位心肌梗死入院治疗,1例因非靶血管病变致心绞痛于术后10个月入院治疗。住院及随访期间无死亡病例发生。结论研究提示药物涂层支架用于急性心肌梗死患者治疗梗塞相关动脉行机械性再灌注安全,可获得与药物涂层支架用于择期的、相对简单的冠状动脉病变的类似疗效。 相似文献