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1.
Summary The aim of this study was to investigate the role of sympathetic nerve and adrenal gland in the changes in hemodynamics and
hypoxic pulmonary vasoconstriction (HPV) induced by cigarette smoking in Wistar rats. Data showed that an increment of pulmonary
vascular resistance (PVR) induced by alveolar hypoxia was partially prevented by prazosin (α1-receptor blocker) and prazosin combined with propranolol (β-receptor blocker), but not significantly affected by propranolol
or adrenalectomy. Cigarette smoking tould increase PVR and potentiate HPV, whereas the potentiation of HPV was partially inhibited
by prazosin and strengthened by propranolol, but not affected by adrenalectomy. It is suggested that the sympathetic nerve
excitation caused by cigarette smoking may play a role in the strengthening of HPV. 相似文献
2.
(王迪浔)(明志)(余上斌)Effectsof3,4-Dihydroxyacetophenone(3,4-DHAP)onHypoxicPulmonaryandSystemicVascularResponseinDogs¥FarmanUllah;WAN... 相似文献
3.
TXB2 and 6-keto-PGF1 α levels in arterial and venous plasma of Wistar and Hilltop rats during hypoxia were measured to investigate the roles of
TXA2 and PGI2 in hypoxic pulmonary vasoconstriction (HPV) and responsiveness difference of pulmonary vessels to hypoxia between different
strains of rats. The results showed that PGI2 might play an important role in maintaining the low resistance in pulmonary circulation of these two strains of rats. Increased
TXA2 during hypoxia may partially mediate HPV in Wistar rats, while augmented PGI2 during hypoxia may modulate HPV in Wistar rats. This might be the important mechanism responsible for more intensive responsiveness
of pulmonary vessels to hypoxia in Hilltop rats than in Wistar rats. 相似文献
4.
目的 通过三维重建CT图像测量参数探讨成人中上胸椎椎弓根钉进钉点(PSEP)与后柱骨性标志的定位关系和变化规律.方法 选取排除了畸形的30例成人中上胸椎CT图像进行三维重建,观察横突椎板凹、横突上嵴和椎板外缘等后柱骨性标志的解剖特征.在重建后的T1~T10特定CT图像上测定以下参数:(1)基础参数,即PSEP至中线的距离(PMD)、横突椎板凹至中线距离(CMD)和半椎板宽度(HLW);(2)目标参数,即点凹距离(PCD)、进钉点定位比(EPLR)和点嵴距离(PRD).比较所有参数两侧测量值的差异和基础参数间测量值的差异,总结从T1到T1o目标参数测量值的变化规律.结果 中上胸椎横突椎板凹、横突上嵴和椎板外缘具有解剖标志明显、恒定且少有增生的特征.T1~T10左右两侧PMD分别为(14.14±2.63) mm和(14.59土2.58) mm,CMD分别为(10.45±2.12) mm和(10.51±2.02) mm,HLW分别为(16.30±1.48) mm和(16.39±1.61) mm,PCD分别为(4.56土1.03) mm和(4.47±0.94) mm,EPLR分别为0.35±0.26和0.33±0.30,PRD分别为(-1.62±1.90)mm和(-1.63±1.44) mm.所有参数两侧测量值差异均无统计学意义(P>0.05).除T2中PMD和HLW相比差异无统计学意义(P>0.05),其余节段基础参数间测量值差异均有统计学意义(P<0.01).从T1到T10,PCD呈现先减小再增大的趋势,T1、T2、T9、T10处PCD均高于T3~T8处(P<o.05);EPLR呈现先增大再减小的趋势,T1~T3处EPLR与其下方任一节段相比差异均有统计学意义(P<0.01),T4~T6、T1o处均低于T7~T9处(P<0.01);PRD呈现先增大再减小的趋势,T1~T3处PRD与其下方任一节段相比差异均有统计学意义(P<0.01),T4~T6处均低于T7~T10处(P<0.01).结论 中上胸椎PSEP与横突椎板凹、横突上嵴和椎板外缘等后柱骨性标志存在相对恒定的定位关系和变化规律,可作为一种新的临床上选择进钉点的方法. 相似文献
5.
Effects of prostaglandins and leukotrienes on hypoxic pulmonary vasoconstriction in rats 总被引:2,自引:0,他引:2
Alveolar hypoxia can induce pulmonary vaso-constriction,but the mechanism of hypoxic pul-monary vasoconstriction remains unknown. It mightrelate to arachidonic acid released from endotheliumor to the vasoactive substances released from othercells in lung tissue during hypoxia.Furthermore,theextra- pulmonary reflex and the directive effectof hy-poxia on pulmonary vascular smooth muscles mightalso be involved.In this study,we conducted in vivorats experiment and employed in vitro perfused lungex… 相似文献
6.
7.
Jin Xian-rong Fan Ming Wang Zhi-qiang Su Yun-chao Yang Guang-tian Hu Han-bo Zhang Ye-ping Feng Chang-jian Ding Yao-xian Wang Di-xun 《华中科技大学学报(医学英德文版)》1990,10(3):134-140
The difference in pulmonary vascular response to hypoxia between Hilltop Sprague-Dawley (HT) rats and Wistar (W) rats was
studied. Effects of inhibitor of leukotriene (LT) synthesis or prostaglandin (PG) synthesis on hypoxic pulmonary vasoconstriction
(HPV) and chronic pulmonary hypertension were observed, and variations in plasma TXB2 and 6-keto-PGF1a during hypoxia were determined. The results showed that in rats of both strains LTs are the major mediator of HPV, which
is also mediated by vasoconstrictive PGs in HT rats, while modulated by vasodilative PGs in W rats. This might be the crucial
mechanism responsible for the higher pulmonary vascular responsiveness in HT rats. Differences in the modulating effect of
histamine and in the structural feature of pulmonary arteriole might be contributing factors as well. 相似文献
8.
Hypoxia increases cytosolic free calcium in porcine pulmonary arterial endothelial cells 总被引:1,自引:0,他引:1
Summary Alteration of cytosolic free calcium ([Ca2+
1]) in hypoxia was studied with fluorescent probe, Fura-2 in cultured porcine pulmonary arterial endothelial cells. It was
found that hypoxia caused by bubbling the cell suspension with 100% N2 increased [Ca2+
2] in endothelial cells by 90±20% (n=8,P<0.05), but didn’t affect that in a Ca2+-free buffer, La3+ (2×10−5 mol/L) inhibited the hypoxia-induced increment in [Ca2+]1, whereas verapamil (10−8 mol/L) didn’t. These findings suggest that hypoxia could induce Ca2+ influx in pulmonary arterial endochelial cells, which might play an important role in vascular response to hypoxia. 相似文献
9.
超声引导股神经-股外侧皮神经阻滞联合喉罩全麻在股骨干骨折手术的应用效果 总被引:1,自引:0,他引:1
目的探讨超声引导下股神经-股外侧皮神经阻滞联合喉罩全麻用于股骨干骨折手术的临床效果。方法选择2014年9月到2018年5月黄山市人民医院收治的股骨干骨折手术患者30例,采用股神经-股外侧皮神经阻滞联合喉罩全麻,超声定位后注入0. 5%罗哌卡因15 mL阻滞股神经和0. 375%罗哌卡因5 mL阻滞股外侧皮神经。观察患者神经阻滞前(T_0)、阻滞后5 min(T_1)、10 min(T_2)、15 min(T_3)、30 min(T_4)的血流动力学变化;观察感觉及运动阻滞的起效和持续时间;同时观察有无恶心、呕吐及术后尿潴留等不良反应。结果 30例患者T_0、T_1、T_2、T_3、T_4收缩压分别为(144. 67±14. 81)、(141. 53±14. 32)、(141. 67±13. 88)、(142. 00±12. 40)、(145. 00±11. 65) mm Hg,不同时间点收缩压的差异无统计学意义(P> 0. 05)。T_0、T_1、T_2、T_3、T_4舒张压分别为(79. 73±4. 39)、(77. 90±4. 29)、(79. 87±3. 87)、(78. 77±4. 29)、(79. 17±3. 48) mm Hg,不同时间点舒张压的差异无统计学意义(P>0.05)。T_0、T_1、T_2、T_3、T_4心率分别为(80.00±4.98)、(78. 90±3. 21)、(78. 33±3. 92)、(79. 33±3. 02)、(78. 07±3. 38)次/分,不同时间点心率的差异无统计学意义(P> 0. 05)。患者感觉阻滞的起效时间平均为(6. 77±0. 90) min,持续时间为(339. 90±65. 67) min;运动阻滞的起效时间平均为(12. 23±2. 28) min,持续时间为(213. 00±39. 08) min。30例患者均无恶心、呕吐及术后尿潴留发生。结论超声引导下行股神经-股外侧皮神经阻滞联合喉罩全麻应用于股骨干骨折手术,血流动力学稳定,镇痛时间长,术后并发症极少,可推广应用。 相似文献
10.
LovastatinisanewcholesterolloweringdrugthatcompetitivelyinhibitsHMG CoAreductase ,whichisanearlyandrate limitingenzymeinthebiosynthesisofcholesterolinhepatocytes[1 ] .In 1 987theFoodandDrugAdministrationapprovedthemarketingoflovastatin[2 ] .Lovastatineffe… 相似文献
11.
Summary Effects of cigarette smoke extract (CSE) and some vasoactive mediators on the production of PGI2 and TXA2 in normoxic and hypoxic pulmonary artery endothelial cells (PAECs) in culture were studied. The production of PGI2 in PAECs was inhibited by hypoxia or verapamil, but promoted by angiotensin II (A II), noradrenaline (NE) or platelet activating
factor (PAF), while that of TXA2 slightly increased except when treated with PAF. The effect of A II, NE, PAF and verapamil, however, was not influenced by
hypoxia. CSE inhibited the production of PGI2 in normoxic PAECs but did not further reduce 6-keto-PGF1α in hypoxic PAECs medium. The results suggested that a) the production of PGI2 during hypoxia might be stimulated by vasoactive mediators produced during hypoxia, not by hypoxia directly; b) the production
and release of PGI, were related to intracellular calcium, c) the augmented production of PGI2 might be one of the mechanisms in the pulmonary vasodilating role of PAF: and d) prostaglandin production might be associated
with the alteration of hypoxic pulmonary vasoreactivity after cigarette smoking. 相似文献
12.
观察了吸入0.004%的一氧化氮(NO)对急、慢性缺氧大鼠血流动力学、缺氧性肺血管收缩反应(HPV)、血气及高铁血红蛋白(MetHb)的影响。结果表明:(1)常氧吸入NO时能明显降低慢性缺氧大鼠肺动脉平均压(Ppa)和肺血管阻力(PVR),但对正常大鼠的Ppa和PVR无明显影响;(2)慢性缺氧大鼠急性缺氧时HPV较正常大鼠弱,吸入NO不但降低两者的急性缺氧肺动脉高压,且完全逆转两者的HPV;(3)吸入NO对急、慢性缺氧大鼠体循环血流动力学、血气及MetHb含量无明显影响。提示吸入NO能选择性降低,急、慢性缺氧性肺动脉高血压,且逆转HPV。 相似文献
13.
Summary To study the bioequivalence of Clavulanate Potassium and Amoxicillin (1∶7) dispersible tablets, a randomized cross—over study
was conducted in 18 healthy volunteers. A single oral dose of 1000 mg Clavulanate Potassium and Amoxicillin (1∶7) dispersible
tablets (Tested formulation, T) or Augmentin syrup (Reference formulation, R). Concentrations in plasma were determined with
high-performance liquid chromatography. The main paramaters of T were: for Clavulanate Potassium and Amoxicillin, Cmax: 2.46±1.11 μg/ml and 18.81±7.26 μg/ml, Tmax: 1.12±0.23h and 1.30±0.34h, ACU(0–6h): 5.18±2.24 μg·h/ml and 45.09±14.53 μg·h/ml, t1/2: 1.43±0.44 h and 1.09±0.22 h., respectively. The relative bioavailability of T to R were 96.5±19.2% and 98.4±26.1%, respectively.
Statistical analysis showed that the two formulations were bioequivalent.
HU Guoxin, male, born in 1957, Associate Professor 相似文献
14.
Summary The direct effect of hypoxia and the effect of hypoxic endothelial cells conditioned medium on cultured pulmonary arterial
smooth muscle cells in vitro were studied with phase contrast microscopy,3H-thymidine labelled technique and flow cytometric measurements. The results showed that direct hypoxia inhibited proliferation
of pulmonary arterial smooth muscle cells, retained pulmonary arterial smooth muscle cells in the Go/G1 phase and decreased3H-thymidine incorporation into pulmonary arterial smooth muscle cells and that hypoxic endothelial cells conditioned medium
stimulated proliferation of pulmonary arterial smooth muscle cells, promoted pulmonary arterial smooth muscle cells from G0/G1 phase to S phase and increased3H-thymidine incorporation into pulmonary arterial smooth muscle cells. It was reasonable to believe that hypoxia might enable
pulmonary arterial endothelial cells to secrete some growth factors which could stimulate proliferation of pulmonary arterial
smooth muscle cells, thereby playing an important role in structural remodeling of the pulmonary arteries and in the development
of hypoxic pulmonary hypertension. 相似文献
15.
目的构建脊柱侧凸动物模型,探讨特发性脊柱侧凸病因学和发病机制,验证脊柱生长失衡假说。方法利用钕铁硼磁体的相互吸引力模拟后路经椎弓根不对称栓系相邻椎体,观察后路栓系对小型猪脊柱生长的形态学三维影响,提出导致脊柱发生畸形的可能阈值范围。16只1月龄雌性小型猪〔体质量为(7.54±0.46)kg〕分为对照组和实验组,每组8只。实验组于T8、T9、T10胸椎后路左侧经椎弓根植入直径为25 mm螺钉和磁体,保持相邻磁体间极性相吸和维持5 mm内距离。对照组仅植入螺钉。每隔4周复查脊柱正侧位片,直至12周。测量体质量、冠状位Cobb角、胸椎后凸角、顶椎(T9)两侧高度及椎体间磁力值的范围,采用完全随机设计量总体均数比较的t检验,确定2组的统计学差异。结果12周后小型猪平均体质量增加约2倍,实验组:(21.05±1.67)kg,对照组:(21.75±1.67)kg,P=0.769,2组差异无统计学意义。对照组小型猪1月龄时T9椎体高度为(6.5±0.60)mm,12周后为(13.06±1.37)mm,平均增加约1倍。实验组小型猪T8-T10的脊柱冠状位Cobb角为11.75°±2.87°,对照组为0.94°±0.86°,差异有统计学意义(P<0.000 1)。实验组矢状面出现胸椎前凸畸形,平均为-5.25°±6.21°,对照组为脊柱后凸,平均为4.25°±0.71°,差异有统计学意义(P=0.003)。结论钕铁硼磁体后路经椎弓根单侧不对称栓系小型猪T8-T10椎体,可以影响其脊柱的生长发育,并可以诱导出猪脊柱冠状面轻度的侧凸畸形和矢状面的前凸畸形。钕铁硼磁体对小型猪椎体生长板产生的栓系力约为1.0~2.3 N。本实验结果验证脊柱侧凸发病机制的脊柱生长失衡假说并且遵循Hueter-Volkmann法则,脊柱后路不对称栓系在脊柱侧凸畸形发生及进展中起重要作用,矢状面的前凸可能是脊柱侧凸的原发畸形。 相似文献
16.
Animalexperimentsdemonstratedthatintrathecallyused5-HThadanalgesicef--.fectll'2].Sumatriptanisaselective5-HT,Dagonist,whichwasclinicallyusedinthetreatmentofmigrainewithgoodeffectandlittlesideeffect[3].Noneuraltoxicitywasfound.Manystudiesconfirmedthatclonidinehadintrathecalanalgesiceffectdependingonitsdosage[4],'butitcouldreducebloodpressure.Theaimofthisexperimentwastostudythetherelationshipbetweenanalgesiceffectsandsideeffectsofepiduralinjectionofclonidineandsumatriptanandthedosages,andtoinv… 相似文献
17.
The chemical nature of the spinal ganglionic neuron with peripheral processes projecting divergently to the somatic and visceral
areas, has been identified by means of tri-labeling method of combining fluorescein tracing with immunocytochemistry. 10 rats
were used. First, 2 μ1 of 2% fast blue(FB) were injected into the left coeliac ganglion. Two days later, 2% nuclear yellow
(NY) was injected into left 9–11 intercostal nerves, 1 μ for each. On the 4th day, the animal was perfused with 10% formal
in in 0.1 mol phosphate buffer. The left T9–11 spinal ganglia were removed and cut into sections by cryostat. The sections were observed under fluorescence microscope and
photographed. The results showed that there were three kinds of neurons in the spinal ganglia; 1) single FB labeled cells
with blue fluorescent cytoplasm accounted for 38.8% of total cells; 2) single NY labeled cells with yellow fluoresceent nuclei
accounted for 52.796; 3) FB and NY double-labeled cells, mostly small or medium in size, accounted for 8.5%. Then, the sections
containing doublelabeled cells were further processed by substance P-demonstrating PAP immunocytochemical staining. The photographs
with immunostaining and fluorescein labelings in the same section were compared. We found that the labeling ratio of SP/NY
was 1.4%, SP/FB was 7%, and SP/NY+FB was 28.8%. The present study detected not only the convergence of somato-visceral sensation
in the spinal ganglia but also the chemical nature of these neurons containing substance P (SP) for the first time. In addition,
these results may provide a morphological basis for the mechanisms of referred pain and somato-visceral reflection. 相似文献
18.
Summary In order to study the effect of nitric oxide (NO) on the expression of hypoxia-inducible factor-1 alpha (HIF-1α) mRNA in hypoxic
pulmonary hypertension (HPH) rats, 30 healthy male Wistar rats were randomly divided into normoxic control group, chronic
hypoxic group and hypoxia plus L-argine (L-Arg) group. The animal model of HPH was developed. The mean pulmonary arterial
pressure (mPAP) was measured by inserting a microcatheter into the pulmonary artery. The HIF-1α mRNA expression levels were
detected by in situ hybridization (ISH) and semiquantitative RT-PCR. It was found that after 14 days hypoxia, the mPAP in
normoxic control group (17.6±2.7 mmHg,l mmHg=0.133 kPa) was significantly lower than that in chronic hypoxic group (35.8 ±6.1
mmHg,t=0.2918,P<0.05) and mPAP in chronic hypoxic group was higher than that in hypoxia plus L-argine group (24.4±3.8 mmHg,t=0.2563,P<0.05). ISH showed that the expression of HIF-1α mRNA in the intraacinar pulmonary arteriolae (IAPA) in normoxic control group
(0.1076±0.0205) was markedly weaker than that in chronic hypoxic group (0.3317±0.0683,t=3.125,P<0.05) and that in chronic hypoxic group was stronger than that in hypoxia plus L-argine group (0.1928±0.0381,t=2.844,P<0.05). RT-PCR showed that the content of HIF-1α mRNA in chronic hypoxic group (2.5395±0.6449) was 2.16 times and 1.75 times
higher than that in normoxic control group (1.1781±0.3628) and hypoxia plus L-argine group (1.4511±0.3981), respectively.
It is concluded that NO can reduce the mPAP by the inhibition of the expression of HIF-1α mRNA, which may be one of the mechanisms
through which NO affects the pathogenesis of HPH.
AO Qilin, male, born in 1971, Lecturer, M. D., Ph. D.
This project was supported by a grant from National Natural Sciences Foundation of China (No. 39730190). 相似文献
19.
目的 评估磁共振高分辨率T2加权成像(HR-T2WI)、分段读出平面回波成像(RS-EPI)和两者联合鉴别肌层与非肌层浸润性膀胱癌的临床价值。方法 前瞻性纳入2016年6月至2017年12月于我院经膀胱镜活组织检查证实为膀胱癌、最终行手术治疗并明确病理分期的9 5例患者,所有患者均行HR-T2WI、RS-EPI检查。分别应用HR-T2WI、RS-EPI及HR-T2WI+RS-EPI图像明确膀胱癌是否浸润肌层,并采用Kappa检验将3种方法的诊断结果与病理结果进行比较。绘制受试者工作特征(ROC)曲线并计算曲线下面积(AUC),评估3种诊断方法的灵敏度、特异度和准确度,采用DeLong检验对3种诊断方法的AUC进行两两比较。结果 HR-T2WI、RS-EPI和HR-T2WI+RS-EPI的诊断结果与病理结果的一致性均较好,Kappa值分别为0.770、0.787、0.936(P均<0.01)。3种方法鉴别肌层与非肌层浸润性膀胱癌的AUC、灵敏度、特异度和准确度分别为0.899、95.5%(42/44)、82.4%(42/51)和88.4%(84/95),0.891、84.1%(37/44)、94.1%(48/51)和89.5%(85/95),以及0.966、93.2%(41/44)、100.0%(51/51)和96.8%(92/95)。HR-T2WI+RS-EPI鉴别诊断肌层与非肌层浸润性膀胱癌的AUC大于HR-T2WI和RS-EPI(Z=-2.627 8、-2.720 5,P=0.008 6、0.006 5)。结论 HR-T2WI联合RS-EPI可作为术前无创、准确鉴别诊断肌层和非肌层浸润性膀胱癌的方法。 相似文献
20.
目的 探讨超声引导下股神经、坐骨神经阻滞联合全身麻醉在下肢骨折手术中的应用。方法 将64例接受下肢骨折手术的患者随机分为两组,对照组(n=32)采用单纯全身麻醉,联合组(n=32)采用全身麻醉联合B超引导股神经、坐骨神经阻滞。比较两组术中不同时刻血流动力学状态、麻醉药物用量、苏醒时间及苏醒后躁动发生情况。结果 T2时刻,联合组和对照组HR、MAP均较T1时刻明显下降(P<0.05),T3~T5时刻,联合组HR、MAP均与T1时刻比较,差异无统计学意义(P>0.05),而对照组均明显高于T1时刻水平(P<0.05)。与对照组比较,联合组术中丙泊酚、瑞芬太尼用量明显减少,苏醒时间、拔管时间明显缩短(P<0.05)。联合组苏醒后躁动的发生率、躁动程度均较对照组明显降低 (P<0.05)。结论 超声引导下神经阻滞联合全身麻醉行下肢骨折手术,可维持术中血流动力学稳定,减少镇痛药物用量,促进早期苏醒和拔管。 相似文献