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61.
为考察Ca~( )在缺氧性肺动脉高压形成中的作用,我们观察了钙通道阻断剂异搏定对慢性连续性缺氧大鼠肺动脉压及左右心功能的影响。将动物置于模拟海拔5000m高原的低压舱内,腹腔注射异搏定,剂量为4mg/kg BW,每日两次。实验结果表明:异搏定可以减弱缺氧15天所引起的肺动脉压升高和右心功能加强的程度,对颈动脉压及左心功能无明显影响,提示Ca~( )的跨膜内流是构成缺氧性肺动脉高压形成的重要基础之一。我们还比较了异搏定对缺氧持续时间不同(15天、10天、5天)的大鼠肺循环的影响,并讨论了异搏定发生作用的机制。  相似文献   
62.
Wang Q  Lin Y  Zhang Q  Sun SQ  Ling XF 《生理学报》2011,63(6):505-510
本文旨在探讨脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)在慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)大鼠模型海马区和血清中的表达情况,以及了解吸烟和气管内注入脂多糖的干预是否参与BDNF表达变化.采用被动...  相似文献   
63.
摘要 目的:探讨疏风解毒胶囊辅以综合管理干预对慢性阻塞性肺疾病(COPD)患者呼吸及运动功能改善的影响。方法:选取2018年10月-2019年10月到我院进行治疗的COPD患者84例作为研究对象,随机数字表法分为两组,患者均使用疏风解毒胶囊进行治疗,对照组(n=42)予以常规干预,试验组(n=42)进行综合管理干预。对比两组患者的临床治疗有效率、肺功能改善情况、肺功能指标、呼吸困难指数(MRC)评分以及6分钟步行实验(6MWT)结果。结果:试验组的临床治疗有效率高于对照组(P<0.05)。干预后,两组动脉血二氧化碳分压(PaCO2)和MRC评分较干预前降低(P<0.05),动脉血氧分压(PaO2)、动脉血氧饱和度(SaO2)、第1秒用力呼气容器(FEV1)、用力肺活量(FVC)、FEV1/FVC均较干预前升高(P<0.05),6MWT距离较干预前增加(P<0.05),且试验组上述指标改善情况更优(P<0.05)。结论:疏风解毒胶囊辅以综合管理干预可提高COPD患者的临床治疗效果,改善其肺功能,可有效缓解呼吸困难,提升运动强度,值得在临床上应用与推广。  相似文献   
64.
目的:探讨波生坦治疗特发性肺动脉高压(IPAH)的疗效与安全性。方法:16例IPAH患者予波生坦口服治疗20周,比较治疗前后患者心功能、6分钟步行距离(6MWD)、肺动脉压力以及血常规、肝肾功能变化。结果:患者心功能由治疗前Ⅲ级13例、Ⅳ级3例变为Ⅱ级14例、Ⅲ级2例。6MWD较治疗前明显延长(P<0.01),肺动脉收缩压、肺动脉平均压及肺动脉舒张压均较治疗前显著降低(P<0.01),患者血常规、肝肾功能较治疗前无明显变化。结论:口服波生坦治疗IPAH可明显改善患者的临床症状与血流动力学指标,安全性好。  相似文献   
65.
Commercial raising of rheas is currently in expansion in the south of Brazil, and many diseases previously restricted to other avian species are currently emerging on rhea farms, especially as a result of careless management of these animals. The objective of the present article is to report a pulmonary aspergillosis outbreak that occurred in great rhea (Rhea americana) in the south of Brazil. About 50 birds aged 30 to 60 days died suddenly and one of them was submitted to autopsy which revealed the presence of white caseous nodules 0.5 mm in diameter occupying 95% of the lung area. One lung was sent to the Federal University of Santa Maria for histopathological and mycological analyses. Histopathological analysis revealed multifocal areas with necrosis and inflammatory infiltrates and the presence of fungal hyphae, giant cells and fibrous tissue proliferation at the periphery. Aspergillus fumigatus was recovered as pure culture from all culture media. This appears to be the first report of aspergillosis among great rhea in Brazil and the second in the world.  相似文献   
66.
Tang B  Tang M  Du YM  Liu CJ  Hong ZG  Luo HY  Hu XW  Song YL  Xi JY  Hescheler J 《生理学报》2004,56(5):625-631
为了从离子通道水平上探讨机体低氧适应的离子机制,本实验将雄性 SD 大鼠随机分为常氧对照组和慢性间歇性低氧组[氧浓度(10 ± 0.5) %, 间断缺氧每天 8 h]。用酶解法急性分离单个大鼠肺内动脉平滑肌细胞(pulmonary artery smoothmuscle cells, PASMCs),以全细胞膜片钳技术记录 PASMCs 膜上的电压门控性钾通道 (voltage-gated potassium channel, KV) 电流,观察急性缺氧对慢性间歇性低氧大鼠 PASMCs 的 KV 的影响, 为机体适应低氧能力提供实验依据。结果显示:⑴常氧对照组在电流钳下,急性缺氧可使膜电位明显去极化(由-47.2 ±2.6 mV 去极到 -26.7 ±1.2 mV ); 在电压钳下, 急性缺氧可显著抑制 KV电流( 60 mV 时, KV电流密度从 153.4 ± 9.5 pA/pF降到 70.1 ± 10.6 pA/pF), 峰电流的抑制率为(57.6 ± 3.3) %, 电流-电压关系曲线向右下移。⑵慢性间歇性低氧组KV电流密度随低氧时间延长而逐渐减少(慢性低氧10 d后就有显著性意义),电流- 电压关系曲线逐渐右下移。⑶急性缺氧对慢性间歇性低氧大鼠PASMCs KV电流的抑制作用随慢性间歇性低氧时间延长而逐渐减弱。上述观察结果提示慢性间歇性低氧减弱急性缺氧对 KV 的抑制, 这可能是机体低氧适应的一种重要机制。  相似文献   
67.
To compare the role of nitric oxide in an adaptive process to chronic hypoxia, we examined the effects of endogenous nitric oxide synthase inhibition on pulmonary vascular tone in conscious sheep and pigs living at high altitude. Unanesthetized male sheep (n=6) and pigs (n=5), born and residing in the highlands of Qinghai Province, China (2,300–3,000 m a.s.l.) were studied at that altitude. Pulmonary artery pressure (Ppa), pulmonary artery wedge pressure (Pcwp), and cardiac output (CO) were measured. Pulmonary vascular resistance (PVR) was calculated as (PpaPcwp)/CO. Using a climatic chamber, hemodynamic measurements during exposures to atmospheric pressures corresponding to altitudes of 0, 2,300, and 4,500 m a.s.l. were performed with and without NO inhibition, using Nw-nitro-l-argine (NLA; 20 mg kg–1), a potent stereospecific competitive inhibitor of nitric oxide synthase. Ppa and PVR at baseline (2,300 m) and during hypoxic exposure (4,500 m) were significantly higher in pigs than in sheep. After NLA administration, Ppa increased and CO decreased in both animals, resulting in significantly increased PVR at baseline and during hypoxic exposure. However, there were no significant differences in the percent increase in basal or hypoxic PVR after NLA administration between sheep and pigs. We conclude that augmented endogenous NO production could contribute to the regulation of pulmonary vascular tone at high altitude in sheep and pigs. However, it is unlikely that NO is responsible for the different pulmonary vascular tones between sheep and pigs at basal condition at moderately high altitude.Communicated by G. Heldmaier  相似文献   
68.
The purpose of this research was to investigate the effects of processing conditions on the characteristics of solid lipid microparticles (SLM) with a potential application as carriers for pulmonary administration. Compritol (5.0% wt/wt) SLM dispersions were prepared by rotor-stator homogenization, at different surfactant concentrations and emulsification times. The SLM were characterized, in terms of morphology and size, after lyophilization and sterilization by autoclaving process. In vivo assessment was carried out in rats by intratracheal instillation of either placebo or SLM dispersion, and by bronchoalveolar lavage for cytological analysis. Mean particle size of 4 to 5 μm was achieved using 0.3% and 0.4% (wt/wt) of emulsifier (Poloxamer 188) and emulsification times of 2 and 5 minutes. The particles showed spherical shape and smooth surface. The morphology of microparticles, the size, and the size distribution were not substantially modified after lyophilization and sterilization. Total cell counts showed no significant differences between placebo and SLM 0.5% or 2.5% groups. Regarding cytology, percentage of polymorphonuclear neutrophils and macrophages did not significantly differ between groups. These results suggest that a single intratracheal administration of the SLMs does not induce a significant inflammatory airway response in rats and that the SLMs might be a potential carrier for encapsulated drug via the pulmonary route.  相似文献   
69.
目的:探讨心房钠尿肽(ANP)对内毒素血症大鼠(ETR)肺动脉和主动脉内皮和平滑肌细胞的调节作用.方法:24只雄性SD大鼠随机分为对照组,模型组(LPS组),治疗组(ANP组).各组分别静脉注射生理盐水、2 mg/kg的LPS和2 mg/kg LPS与2μg/kg的ANP,4 h后处死动物分离肺动脉、主动脉,进行离体血管务体外灌注实验.结果:LPS组、ANP治疗组主动脉环和LPS组肺动脉环对去甲肾上腺素(NE)引起的收缩作用在NE低浓度时较对照组减弱(P<0.01),在较高浓度时较对照组均明显增强(P<0.01);主动脉环ANP治疗组与LPS组无显著差异(P>0.05);肺动脉环ANP治疗组与对照组相比无显著差异(P>0.05).ANP可明显改善ETR离体主动脉和肺动脉对乙酰胆碱(ACh)的舒张反应(P<0.01),ANP可提高ETR离体主动脉和主动脉环对硝普钠(SNP)引起的舒张反应的敏感性(P<0.01).结论:ANP对ETR肺动脉和主动脉内皮和平滑肌细胞可能存在调节作用.  相似文献   
70.
The crocodilian spinal vein is remarkably robust yet historically overlooked. Using corrosion casting, we describe the anatomy of this vessel and its connections with the caval and hepatic venous systems in representatives from four crocodilian genera. The spinal vein arises from an enlarged occipital sinus over the medulla and extends the entire length of the vertebral column. Unlike in squamate reptiles, the spinal vein is single (nonplexiform), voluminous, and situated dorsal to the spinal cord, and plexi lateral to the cord span between emerging intercostal veins. The connections with the other venous systems are otherwise similar to those in other tetrapods. The overall anatomy of this vessel and its abundant connections with the other venous systems indicate it likely plays a primary role in returning blood to the heart from all parts of the body. Preliminary studies of function suggest that this vessel could also play an adaptive role during basking and diving.  相似文献   
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