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121.
Angiotensin II (Ang II) type 2 receptors (AT2Rs) have been associated with apoptosis. We hypothesized that AT2Rs are increased in stroke and may contribute effects of stroke to the brain. To test this, we have examined the expression of Ang II type 1 receptor (AT1R), AT2R and Ang II levels in the brain 24 h after transient middle cerebral artery occlusion (MCAO). The densities of AT1R and AT2R were measured by quantitative autoradiography (n=6). The levels of Ang II were measured by radioimmunoassay (RIA) (n=6) and by immunohistochemistry (n=3). AT1R levels on autoradiography showed a significant decrease (0.87±0.06 to 1.39±0.07 fmol/mg, p<0.01) in the ventral cortex of the stroke side compared to the cortices of non-stroke (NS) rats (n=4). There was no significant difference on ATIR in the contralateral verbal cortex of the stroke rats compared to NS control. In contrast, levels of AT2R in the ventral cortex of both the stroke and the contralateral sides were significantly increased (0.77±0.06, p<0.05 and 0.91±0.05, p<0.01 compared to 0.60±0.03 fmol/mg tissue, respectively). RIA showed that Ang II in the ventral cortex of both the stroke and the contralateral sides were significantly increased (241.63±47.72, p<0.01 and 165.51±42.59, p<0.05 compared to 76.80±4.10 pg/g tissue, respectively). Also, Ang II in the hypothalamus was significantly increased (179.50±17.49 to 118.50±6.65 pg/g tissue, p<0.05). Immunohistochemistry confirmed the increase of Ang II. These results demonstrate that brain Ang II and AT2Rs are increased whereas AT1Rs are decreased after transient MCAO in rats. We conclude that in stroke, Ang II and AT2R are activated and may contribute neural effects to brain ischemia.  相似文献   
122.
The goal of this study was to determine the in vivo pulmonary arterial buffering function (BF) during acute and moderate pulmonary hypertension achieved by phenylephrine-induced smooth muscle activation.Pulmonary pressure (Konigsberg P7) and diameter (sonomicrometry) were measured in nine anesthetized sheep. Transit pulmonary arterial hypertension was induced by mechanical occlusion of the pulmonary artery (HP) and by phenylephrine infusion (5 g/kg/min) (PHE). A viscoelastic Kelvin-Voigt model was used. By increasing the values of the viscous modulus, the pressure-diameter hysteresis area was reduced to a minimum in order to obtain the purely elastic pressure-diameter relationship. The elastic index (E) was calculated as the first derivative of the exponential model of the purely elastic pressure-diameter relationship at the mean pressure point.Systolic, diastolic, mean and pulse pressures were similar during HP and PHE, but significantly higher with regard to control steady state. In HP, E and arterial diameter (both its minimum and maximum values) increased significantly. In contrast, when pulmonary hypertension was induced by VSM activation, E was maintained concomitantly with pulmonary artery vasoconstriction.Pulmonary hypertension produced by occlusion of the pulmonary artery increases elasticity. Smooth muscle activation may offset the deleterious effect of pulmonary hypertension on arterial wall elasticity by reducing E and impeding arterial dilatation and collagen recruitment, maintaining BF during pulmonary hypertension.  相似文献   
123.
To show the relationships of calcium accumulation in the thoracic aorta to the other tissues, calcium contents were determined with a microwave-induced plasma-atomic emission spectrometer on arteries, veins, cartilages, ligaments, and bones. These tissues were resected from 18 individuals, consisting of 11 men and 7 women who died in the age range 59–91 yr. As thoracic and abdominal aortas are routinely used for radiographic examination of arterial calcification, they appear to be standard tissues of the calcium accumulation. The calcium accumulations were determined in the femoral artery, the superior and inferior venae cavae, the internal jugular vein, cartilages of the articular disk of the temporomandibular joint and the intervertebral disk, both the ligaments of the anterior cruciate ligament and the ligamentum capitis femoris, and the calcaneus, in contrast with the thoracic aorta. As calcium increased in the thoracic aorta, it increased in the femoral artery, the articular disk of the temporomandibular joint, the intervertebral disk, both ligaments of the anterior cruciate ligament, and the ligamentum capitis femoris, but it did not increase in veins, such as the superior and inferior venae cavae and the internal jugular vein. In contrast, it decreased in the calcaneus.  相似文献   
124.
Expressionofmilkproteingenesisinvolvedinahugenetworkofregulatorycircuitswhicharelinkedtotheintactdevelopingmammarygland,andhomeostasisduringpuberty,pregnancy,lactationandinvolution.Analysisofputativeregulatoryelementsandhybridgeneintissueculturesystems…  相似文献   
125.
摘要 目的:探讨地塞米松复合罗哌卡因臂丛神经阻滞(BPB)对儿童肱骨髁上骨折患儿术后镇痛效果的影响。方法:择期行肱骨髁上骨折手术的患儿140例,随机分组为对照组70例与试验组70例。麻醉后两组均于超声引导下实施BPB,其中对照组予以0.25%罗哌卡因药液,试验组予以0.25%罗哌卡因、0.1 mg/kg地塞米松所组成的混合药液。记录两组患儿痛觉阻滞时间;于患儿苏醒后10 min、术后2 h、术后6 h、术后12 h及术后24 h,采用FLACC评分对患儿疼痛程度进行评估;记录两组患儿术后24 h内镇痛药物使用情况;记录两组患儿术后首次下床活动时间和术后住院时间;记录两组术后24 h内不良反应发生情况。结果:与对照组相比,试验组痛觉阻滞时间显著延长(P<0.05)。与对照组相比,试验组术后2~24 h的疼痛评分均显著降低(P<0.05)。试验组术后24 h布洛芬混悬液使用次数显著少于对照组(P<0.05),曲马多使用率显著低于对照组(P<0.05)。与对照组相比,试验组下床活动时间提前(P<0.05),术后住院时间缩短(P<0.05)。两组不良反应发生率无统计学差异(P>0.05)。结论:地塞米松复合罗哌卡因行BPB能够为肱骨髁上骨折患儿提供良好术后镇痛效果,利于患儿术后恢复。  相似文献   
126.
Paraoxonase 1 (PON 1) is a high‐density lipoprotein (HDL)‐associated enzyme with antioxidant function protecting low‐density lipoprotein (LDL) from oxidation. PON 1 has two amino acid polymorphisms in coding region; L/M 55 and Q/R 192. These polymorphisms modulate paraoxonase activity of the enzyme. PON 1 activity decreases in coronary artery disease (CAD). In the present study, distribution of PON 1 L/M 55 and Q/R 192 polymorphisms and the effect of these polymorphisms on the activities of PON 1, and on the severity of CAD in 277 CAD (+) patient and 92 CAD (?) subjects were examined. PON 1 L/M 55 and Q/R 192 genotypes were determined by PCR, RFLP and agarose gel electrophoresis techniques. Genotype distributions and allele frequencies for PON 1 Q/R 192 polymorphism were not significantly different between controls and CAD (+) patient group (p > 0.05), but in genotype and allele distribution of PON 1 L/M55 polymorphism, there was significantly difference among groups (p < 0.05). Genotype distributions for both polymorphisms were not significantly different between subgroups of single‐vessel disease (SVD), double‐vessel disease (DVD) and triple‐vessel disease (TVD). Serum PON 1 activity was lower in CAD (+) group than in controls and this was also statistically significant (p < 0.001). In both groups, the highest PON activities were detected in LL and RR genotypes. In summary, our results suggest that there is an association between the PON 1 L/M 55 polymorphism of paraoxonase and CAD in Turkish patients but not with PON 1 Q/R 192 polymorphism. However, it is hard to correlate these polymorphisms and severity of CAD. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
127.
在最新研究发现的系统性血管保护的优化治疗策略表明,血管损伤机制与胰岛素抵抗、糖尿病肾病及外周动脉疾病(PAD)的发病机理相关。胰岛素抵抗机制在血管损伤方面主要表现为大血管和微血管病变。系统性动脉硬化性疾病的及时诊断和干预是至关重要的。并且,治疗方面不仅仅是改善现有疾病状况,也应注意减少心血管事件的风险。这些努力有助于降低心血管事件的风险和死亡率。PAD的治疗包括药物治疗、血管内治疗和血管重建,以及运动疗法。经典治疗药物包括血管舒张剂,如贝前列素和抗血小板药物。值得注意的是,贝前列素除血管舒张活性外还有几个其他治疗作用,包括保护血管内皮、抗血小板和抗炎作用。最近的前期临床研究表明,贝前列素不仅通过其舒张血管活性改善四肢缺血,同时改善了影响血管内皮功能的胰岛素抵抗。贝列前素的应用,在早期疾病阶段维持血管内皮功能,减少血管事件的发生率,发挥其系统性血管保护作用。这样,贝列前素最终将有助于改善患者的生存质量并可能增加PAD患者的寿命。  相似文献   
128.
目的:对比选择性冠状静脉动脉化(SCVBG)搭桥治疗弥漫性右冠状动脉狭窄病变中选择乳内动脉和大隐静脉作为桥血管的治疗效果。方法:选择2008年10月到2014年10月在我院行SCVBG搭桥的84例患者资料,其中选择大隐静脉作为桥血管进行冠状静脉动脉化搭桥患者46例(大隐静脉桥组),选择乳内动脉作为桥血管进行冠状静脉动脉化搭桥患者38例(乳内动脉桥组)。随访记录两组患者的生存情况、近期复查超声心动图、冠状动脉CTA及心绞痛复发率。结果:乳内动脉桥组患者总生存率(100%)明显高于大隐静脉桥组(82.6%)(P0.05)。乳内动脉桥组患者桥血管和心中静脉通畅率(100%)明显大于大隐静脉桥组(54.35%)(P0.05)。两组患者左心室射血分数(LVEF)较治疗前明显增加,左心室舒张期末内径(LVEDD)较治疗前明显减小(P0.05)。治疗后,乳内动脉桥组患者心绞痛复发率明显小于大隐静脉桥组(P0.05)。结论:SCVBG搭桥治疗弥漫性右冠状动脉狭窄病变中,选择乳内动脉桥效果优于大隐静脉桥,能明显提高桥血管和心中静脉通畅率,降低心绞痛复发率。  相似文献   
129.
目的:探讨剖宫产瘢痕妊娠(CSP)的合理治疗方案。方法:回顾性分析2007年1月至2013年12月我院收治的26例CSP患者的临床资料,对其病史、临床表现、处理及结局进行总结分析,重点探讨其治疗方案与预后的关系。结果:采用的治疗方式包括口服米非司酮配伍米索前列醇后超声监测下清宫术6例、超声监测下局部甲氨蝶呤注射3例、全身甲氨蝶呤注射后清宫术2例、子宫动脉(化疗)栓塞后清宫术16例、经腹病灶切除术1例、经腹全子宫切除术1例。前三种方法尽管具有一定的成功率,但均有较高的术后大出血风险。子宫动脉(化疗)栓塞在CSP的初始及抢救治疗中均具有很高的成功率。结论:CSP治疗方案的选择需根据患者的病情、妊娠部位、生育要求等多方面进行综合考虑。在现有的治疗方案中,子宫动脉(化疗)栓塞后清宫术具有较大的优势。  相似文献   
130.
目的:探讨严重弥漫性冠状动脉病变患者在非体外循环下行序贯旁路移植手术联合内膜剥脱的临床效果及安全性。方法:按照随机数字表法将2011年3月~2013年3月我院收治的110例严重弥漫性冠状动脉病变患者分为治疗组54例和对照组56例。治疗组在非体外循环下行序贯旁路移植结合内膜剥脱治疗,对照组在非体外循环下行冠状动脉旁路移植结合内膜剥脱治疗,比较两组的临床效果及围手术期并发症。结果:治疗组围手术期死亡2例(3.70%),对照组死亡4例(7.14%),两组死亡率比较差异无统计学意义(x2=0.631,P=0.427)。围手术期内治疗组心肌梗死、严重心脑血管不良事件以及新发房颤的发生率低于对照组,差异有统计学意义(P0.05)。治疗组术后1年吻合口通畅程度和桥血管通畅程度均优于对照组,差异均有统计学意义(Z=-2.416,-2.456;P=0.016,0.014)。结论:在非体外循环下序贯旁路移植同期行内膜剥脱治疗严重弥漫冠状动脉病变具有并发症少、安全性高且疗效好的特点,值得临床推广使用。  相似文献   
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