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91.
目的:研究左旋精氨酸、牛磺酸、卡托普利单用及合用对自发性高血压大鼠的血压以及血神经肽Y、血脂水平的影响。方法:①用MRB-ⅢA型血压记录仪(上海第二医科大学高血压研究所),在大鼠清醒状态下,测鼠尾的尾动脉收缩压。②用酶法测定血清胆固醇(TC)、甘油三酯(TG)。③用^125I标记法和放射免疫法测血浆神经肽Y。结果:①经过四周药物治疗,左旋精氨酸且(L-arg)、牛磺酸组(Tau)血压均无变化(P>0.05)。卡托普利组(Cap )、三药合用组(L-arg Tau Cap)血压均下降(P<0.0005),L-arg Tau Cap组,血压下降比卡托普利组明显(P<0.01)。②经过四周药物治疗,牛磺酸组TC降低,TG无变化。L-arg Tau Cap组TC和TG均降低,左旋精氨酸组、卡托普利组TC和TG均无变化(P>0.05)。③经过四周药物治疗,左旋精氨酸组、牛磺酸组NPY无变化(P>0.05)。卡托普利组、L-arg Tau Cap 组NPY下降。用药前后,四组SHR大鼠血压高低与血浆神经肽Y的浓度均呈正相关(P<0.05)。结论:①四组大鼠治疗后,左旋精氨酸、牛磺酸组血压换变化;卡托普利组和合用组均出现血压降低,合用组降压效果经弹卡托普利明显。②牛磺酸治疗组血清胆固醇降低;三种药物合用组血清胆固醇和甘油三酯的降低。左旋精氨酸组、卡托普利组血脂无变化。③自发 性高血压大鼠的血压变化与血浆神经肽Y浓度的变化呈正相关,神经肽Y可能参与了高血压的发生发展。 相似文献
92.
Renin- angiotensin system( RAS) candidat-ing gene,such as angiotensinogen( Ag T) as wellas angiotensin- converting enzyme( ACE) genepolymorphism were thought to have positive association with various cardiovasculardiseases.In1 992 ,Jeunemaitre[1] detected a microsatellitepolymorphism in the region of the an-giotensinogen gene which has linked to occur-rence of essential hypertension.Further analysisled to detection of several mutations in the cod-ing region of angiotensinogen gene[2 ] . Ma… 相似文献
93.
自发性高血压大鼠左室不同部位心肌纤维化程度的改变: 病理变化与心肌密度改变的对比观察 总被引:1,自引:0,他引:1
目的:探讨自发性高血压大鼠(SHR)左室室间隔、前壁、后壁及侧壁 心肌纤维化的动态变化,以及心脏超声显像结合计算机分析检测心肌密度这一方法的可靠性。方法:应用病理及生化检查,检测SHR左室室间隔、间壁、后壁及侧壁心肌纤维化的病变程度;通过心脏超声显像并结合计算机分析,检测大鼠的心肌密度的变化。结果:14周时,代表心肌纤维化水平的参数羟脯氨酸浓度(HC)在SHR室间隔、前壁及后壁即已增高,以室间隔最为明显,而左室侧壁虽有增高趋势,但未达到显著性水平;24周时各部位均明显增加,但各部位之间的差异明显减少。在14周时,代表血管周围纤维化水平的参数血管周围胶原面积(PVCA)在左室各部位较对照组均显著增高,24周时增高更为明显,但各部位之间无显著性差异。而代表间质纤维化水平的参数胶原容积分数(CVF)在14周时只有室间隔显著增高,其余各部位无明显变化;24周时各部位均有显著增高,但仍以室间隔增高最为明显。心肌灰度均值在14周时各部位均较对照组显著增高,各部位之间比较,室间隔最高,侧壁最低,二者之间有显著性差别。24周时各部位均较14周显著增高,但各部位之间差别变小。在室间隔,灰度离散度在14及24周均未出现显著性改变,而其他部位则在14周时增高,24周时趋于正常。结论:在高血压发病过程中,心肌纤维化尤其是间质纤维化的变化程度是不均衡的,以室间隔程度最重,左室侧壁最轻;应用心脏超声显像并结合计算机分析测定心肌密度,可客观地反应心肌纤维化的程度。 相似文献
94.
目的:观察原发性高血压患者红细胞[Ca^2 ]i,多巴胺β羟化酶及ATP含量变化并分析其结果。方法:测定35例高血压患者的红细[Ca^2 ]i、ATP、血清多巴胺β羟化酶活性,血糖及血浆胰岛素含量,并以30例健康成年人为对照。结果:高血压患者的红细胞[Ca^2 ]i、ATP、多巴胺β羟化酶均明显高于对照组(P<0.05,P<0.01),但血糖与胰岛素未见明显变化。结论:高血压患者血清多巴胺β羟化酶活性增强伴随ATP与[Ca^2 ]i升高。 相似文献
95.
96.
《Surgery (Oxford)》2021,39(9):577-590
Epistaxis is a common problem that can affect the whole population. The majority of cases are self-limiting and do not require any medical intervention, but epistaxis can be associated with morbidity and even death in very rare circumstances. If epistaxis does not resolve with first aid measures, or episodes are frequent, patients may require specialist assessment and treatment by ENT, either in the outpatient clinic or via an unscheduled (emergency) admission to the hospital. Here, we provide an overview of the management of epistaxis in the outpatient setting and during an emergency admission in both paediatric and adult patients. We highlight the key considerations in the history and management, covering the common and rare conditions that are associated with epistaxis. This article provides an update from our previous article published in 2018 to include the more recent literature and a useful learning resource for examinations. 相似文献
97.
Hye-Sung Jo Jae Hyun Han Yoon Young Choi Jin-I Seok Young-In Yoon Dong-Sik Kim 《肝胆外科与营养》2021,10(3):325
BackgroundExcessive portal pressure after massive hepatectomy can cause hepatic sinusoidal injury and have deleterious impacts on hepatic functional recovery, contributing to developing post-hepatectomy liver failure. This study aimed to assess the effects of splanchnic vasoactive agents on hepatic functional recovery and regeneration while clarifying the underlying mechanism, using a 70% hepatectomy porcine model.MethodsEighteen pigs undergoing 70% hepatectomy were involved in this study and divided into three groups: control (n=6), terlipressin (n=6), and octreotide (n=6). Terlipressin (0.5 mg) and octreotide (0.2 mg) were administered 3 times a day for each group with the first dose starting just before surgery until the 7th postoperative day, at which time the surviving pigs were sacrificed. During the period, portal pressure, liver weight, biochemical analysis, histological injury score, and molecular markers were evaluated and compared between groups.ResultsThe 7-day survival rates in the octreotide, terlipressin, and control groups were 100%, 83.3%, and 66.7%, respectively. The portal pressures decreased in both terlipressin and octreotide groups than the control group at 30 minutes, 1 hour and 6 hours after hepatectomy. The amount of regeneration measured by liver weight to body weight ratio at the time of sacrifice in the terlipressin group was smaller than that in the control group (117% vs. 129%, P=0.03). Serum aspartate aminotransferase (AST) and total bilirubin levels at 1 and 6 hours after hepatectomy and prothrombin time/international normalized ratio (PT/INR) at 6 hours after hepatectomy were significantly improved in the terlipressin and octreotide groups compared to the control group. Serum endothelin-1 (ET-1) was significantly lower in the terlipressin group than that in the control group 6 hours after hepatectomy (P<0.01). The histological injury score in the control group was significantly higher than that in the terlipressin group on the 7th postoperative day (P<0.01).ConclusionsSplanchnic vasoactive agents, such as terlipressin and octreotide, could effectively decrease portal pressure and attenuate liver injury after massive hepatectomy. 相似文献
98.
99.
J. Plum M. Hollenbeck P. Heering B. Grabensee 《Journal of molecular medicine (Berlin, Germany)》1990,68(9):476-484
Summary In order to investigate the behaviour of atrial natriuretic peptide (ANP) in untreated mild to moderate essential hypertension and the influence of blood pressure normalisation by a
1-receptor blocker a study was conducted in groups of normotensive and hypertensive middle aged subjects. 10 normal subjects and 10 patients with essential hypertension (WHO I–II) without any medication and on betaxolol monotherapy were studied at rest and during graded exercise. In addition the response of ANP, cyclic guanosine monophosphate (cGMP) and the renin-aldosterone-system was investigated.Normal subjects and hypertensive patients did not differ in ANP levels at rest and also responded with a comparable exercise dependent increase at all workload levels. A steady decrease of ANP was noticed during the recovery period in both groups. After-blocker treatment in the hypertensive patients ANP concentrations significantly rose, both at rest and more pronounced during exercise. cGMP reacted in a similar way but showed a more inert response. A counter-regulatory behaviour between ANP and PRA or aldosterone, as seen under volume shifts, could not be detected. These findings demonstrate that plasma ANP is not altered in untreated essential hypertension. Increased ANP levels in
1-blocker treatment may contribute to its blood lowering effect.
Abkürzungsverzeichnis ANP atriales natriuretisches Peptid - ALD Aldosteron - CIn Inulin Clearance - cGMP zyklisches Guanosinmonophosphat - irANP immunoreaktives atriales natriuretisches Peptid - PAH Paraaminohippursäure - PRA Plasma-Renin-Aktivität - RAA-System Renin-Angiotensin-Aldosteron-System - RBF renaler Blutflu - RIA Radioimmunoassay - RVR renaler Gefä\widerstand 相似文献
Abkürzungsverzeichnis ANP atriales natriuretisches Peptid - ALD Aldosteron - CIn Inulin Clearance - cGMP zyklisches Guanosinmonophosphat - irANP immunoreaktives atriales natriuretisches Peptid - PAH Paraaminohippursäure - PRA Plasma-Renin-Aktivität - RAA-System Renin-Angiotensin-Aldosteron-System - RBF renaler Blutflu - RIA Radioimmunoassay - RVR renaler Gefä\widerstand 相似文献
100.
目的 观察哇巴因与地高辛对大鼠肝脏钠泵基因表达的影响 .方法 分别给大鼠注射哇巴因 (2 0 μg· kg- 1·d- 1 )、地高辛 (32 μg·kg- 1·d- 1 )和生理盐水 (1m L· kg- 1·d- 1 ) ,观察给药后 6wk大鼠血压的动态变化 ;并分别应用分子生物学 RT- PCR及免疫组织化学技术 ,探讨各组大鼠肝脏钠泵 α1 ,α2 及 α3 亚单位 m RNA及蛋白水平基因表达的改变 .结果 给予哇巴因 2 wk后大鼠血压开始升高 ,至 6 wk时明显高于生理盐水组 (17.7± 1.2 ) vs(15 .4± 1.1) k Pa,P<0 .0 1) ,而实验过程中地高辛组血压与对照组比较差异不明显 .无论是在 m RNA水平还是在蛋白水平 ,哇巴因对大鼠肝脏钠泵α1 亚单位表达无影响 ,而地高辛使α1 亚单位表达增强 ;两组大鼠 α2 亚单位表达均无改变 ;哇巴因使 α3 亚单位蛋白水平表达减弱 ,而 m RNA水平增强 ,地高辛组大鼠肝脏钠泵 α3 亚单位无论在 m RNA水平及蛋白水平表达均增强 .结论 哇巴因在高血压发病中可能起着重要作用 ;哇巴因与地高辛可导致不同的钠泵基因表达改变 ,为进一步揭示内源性哇巴因生理与病理作用以及洋地黄类药物药理与毒理作用的分子机制提供了理论及实验依据 相似文献