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51.
The sympathetic nervous control of the vascular bed of cat gastrocnemius muscle was studied with a new whole-organ technique which permits simultaneous, continuous and quantitative measurements of capillary pressure (Pc), capillary fluid exchange and resistance reactions in the whole vascular bed and in its three consecutive sections: large-bore arterial vessels (> 25 μm), arterioles (< 25 μm) and veins. The results demonstrated a distinct neural control of all three consecutive vascular sections, graded in relation to the rate of nerve excitation up to maximum at 16 Hz. Stimulation at high rates, which in the steady state caused an average rise of overall regional resistance from 15.3 to 120 PRU (7.8-fold increase), thus raised large-bore arterial vessel resistance from 8.8 to 64 PRU (7.3-fold increase), arteriolar resistance from 4.5 to 49 PRU (10.9-fold increase) and venous resistance from 2.0 to 7 PRU (3.5-fold increase). The rate of resistance development (PRU s-1) of the sympathetic constrictor response was much higher in the arteriolar than in the other sections, which indicates that the neural control is especially prompt and efficient in the arterioles. A passive component was shown to contribute to the described responses only on the venous side, but in no case by more than 10% of the total sympathetic venous resistance response, which thus is mainly active. Of special functional importance was that the new technique provided information about the adrenergic control of Pc, in absolute figures. From the control value of 19 mmHg, graded sympathetic stimulation caused a graded decline in Pc, at maximum constriction by about 7 mmHg. This resulted in marked net transcapillary fluid absorption, in turn increasing plasma volume.  相似文献   
52.
Branches of the splenic artery and splenic arterial segments   总被引:2,自引:0,他引:2  
In 200 adult autopsy specimens, the arterial supply to the pancreas and spleen was studied radiologically and by manual dissection. The splenic artery divided into two or three lobar arteries, which supplied its corresponding lobe; each lobar artery subsequently divided into two to four lobular branches. Six to twelve lobular branches were observed entering the splenic substance at the hilum. Lobar arteries did not anastomose with each other, hence, the lobes of the spleen are also termed segments. The lobules, however, were not found to be independent segments and the arteries of one lobule anastomosed with those of other lobules. The branching pattern of the splenic artery varied from one specimen to another, so much so that a prevailing pattern could not be identified. Polar arteries, particularly to the superior pole, arose quite proximal to the hilum in 51% of cases and were occasionally missed. In 45% of males and 40% of females, the posterior gastric artery arose from about the middle of the splenic artery. The splenic artery was not found to be tortuous in fetuses, newborns, and young children. Tortuosity was seen in only 10% of adults; thus, the characteristic tortuosity of the splenic artery appears to develop with age.  相似文献   
53.
The involvement of cAMP- and cGMP-dependent signal systems into the regulation of the contractile reaction of smooth muscles of the rabbit pulmonary arteries was studied using a mechanographic method. For modulation of intracellular level of cyclic nucleotides we used adenylate cyclase activators -adrenoceptor agonist isadrin, guanylate cyclase inhibitor methylene blue, penetrating analog dibutyryl-cAMP, and phosphodiesterase inhibitors. The mechanisms of cAMP- and cGMP-dependent regulation of smooth muscle contractile activity were realized in close interrelationship, and the key component of this was cyclic nucleotide phosphodiesterases. The ratio of activities of phosphodiesterase subtypes in smooth-muscle cells can essentially modulate the adrenergic effects in the pulmonary artery wall and even invert them.  相似文献   
54.
Summary An anatomical study of the superficial and deep circumflex iliac arteries in 43 formalin-fixed cadavers is presented. The origin, calibre, course, branches, symmetry and variations of the vessels are pointed out as well as their special features related to surgical applications.
Etude anatomochirurgicale des artères circonflexes iliaques superficielle et profonde: bases anatomiques de la confection du lambeau libre iliaque composé cutanéo-osseux
Résumé Une étude anatomique des artères circonflexes iliaque superficielle et profonde est effectuée sur 43 cadavres formulés. L'origine, le calibre, le trajet, les branches, la symétrie et les variations des vaisseaux sont mis en évidence ainsi que leurs caractères particuliers en vue d'une application chirurgicale.
  相似文献   
55.
Bilateral occlusion of carotid arteries in awake hypertensive rats (SHR-SP) was used as a model of global brain ischemia (duration of occlusion — until appearance of seizures). In normotensive rats (WKY), no seizures developed over 60 min. We revealed swelling of mitochondria in dendrites of hippocampal CA1 pyramidal cells, which was more pronounced in SHP-SP than in WKY rats. Blood pressure and heart rate in SHR-SP rats increased starting from the first minutes of occlusion, while in WKY rats these parameters remained unchanged. We proved that bilateral occlusion of the carotid arteries in awake SHR-SP rats can be used as an adequate model of global cerebral ischemia. Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 146, No. 12, pp. 627–630, December, 2008  相似文献   
56.
目的:探讨小陷胸汤加味中药方对血管内皮细胞的保护作用。方港:建立ox-LDL损伤人脐静脉内皮细胞株(ECV-304)模型,用小陷胸汤加味含药血清处理模型,并用放免和硝酸酶还原法在药物干预6h和24h后检测细胞上清液中ET-1和NO含量。结果:100 μg/ml的ox-LDL可损伤血管内皮细胞并导致其分泌NO和ET-1功能失调,小陷胸汤加味含药血清通过影响NO/ET-1的分泌而明显改善此失调状态。结论:小陷胸汤加味中药通过调节NO/ET-1水平显著拮抗ox-LDL对血管内皮细胞损害,具有防治AS的作用。  相似文献   
57.
Summary Two arterial systems contribute to the blood supply of the penis. The deeper system, responsible for supplying the erectile tissues, arises from the internal pudendal arteries (a. pudendae internae), or sometimes from an accessory internal artery. Four branches, either collateral or terminal, should be considered: the artery to the bulb of the penis, the urethral artery, the deep artery of the penis and the dorsal artery of the penis. Variations are frequently present in the origin, distribution and symmetry of these arteries, but on the whole the blood supply is organised into three planes, inferior or ventral, middle and deep, superior or dorsal. These three planes are complementary: when the blood supply to any one of them is occluded, at whatever level this may be, the blood supply is supplemented by the plane immediately above it. Arteriograms should be interpreted with caution because anatomical variations may at first sight be taken for pathological change.The superficial system, supplying the tissues around the erectile organs, arises from the lateral inferior pudendal arteries. Three types of supply have been described, according to whether the right and left arteries have a symmetrical distribution or whether the arterial network arises in large part or totally from one side.
Contribution à l'étude de la vascularisation artérielle du pénis
Résumé Deux systèmes artériels participent à la vascularisation du pénis. Le système profond, tenant sous sa dépendance les organes érectiles, a pour origine les artères honteuses internes (a. pudendae internae), parfois une artère interne accessoire. Quatre branches, collatérales ou terminales sont à considérer: l'artère du bulbe du pénis, l'artère urètrale, l'artère profonde du pénis, l'artère dorsale. Il existe de fréquentes variations dans l'origine, la distribution et la symétrie de ces artères mais, dans son ensemble, la vascularisation est organisée selon trois plans, inférieur ou ventral, moyen ou profond, supérieur ou dorsal. Ces trois plans sont complémentaires: lorsque l'un d'eux s'épuise, à quelque niveau que ce soit, le relais est pris par le plan immédiatement supérieur.Le système superficiel, vascularisant les enveloppes provient des artères honteuses externes inférieures. Trois types de vascularisation sont décrits, selon que les deux artères droite et gauche ont une distribution symétrique ou que le réseau artériel provient en majeure partie ou totalement d'un seul côté.
  相似文献   
58.
目的:初步探讨在异基因造血干细胞移植(HSCT)中发生移植物抗宿主病(GVHD)患者DC40L表达的变化以及意义。方法:HSCT治疗重型β-地中海贫血(n=12)和遗传性溶血性贫血(n=1)成功植入的儿童患者,其中脐血移植(UCBT)8例,异基因外周血造血干细胞移植(allo-PBSCT)5例,在移植前、移植后发生GVHD时采用流式细胞仪检测和比较外周血中CD40L和CD40的表达。结果:3例UCBT无GVHD,其余均发生了Ⅰ-Ⅳ度急性GVHD。急性GVHD发生时CD4^ CD40L^ 和CD8^ CD40LT细胞表达明显升高,allo-PBSCT者更明显;慢性GVHD发生时患者的CD40L^ 、CD25^ 和CD69^ 在CD4^ 和CD8^ T细胞上的表达亦增加。CD19^ CD40^ B细胞的表达在UCBT和allo-PBSCT的3个月内则一直处于低于正常的水平。结论:CD40L高表达与GVHD的发生相关,提示CD40-CD40L共刺激途径在GVHD的发生中可能起着重要作用。  相似文献   
59.
目的摸索人脐血间充质干细胞(mesenchymal stem cell,MSC)的培养条件。方法根据不同采血量、首次换液时间、胎龄、不同培养基对样本分组,比较不同培养条件对脐血中的间充质干细胞原代生长的影响,以流式细胞仪对培养出的间充质干细胞进行细胞表面标志检测。结果在相同条件下,取10ml的脐血能较大程度培养出间充质干细胞;观察首次换液时间在培养后96h较为合适,延长换液时间有利于数量不占优势的单核细胞充分贴壁:早产胎儿的脐血培养出的间充质干细胞成功率较高;胎牛血清的质和量决定了培养成功与否。培养出的间充质干细胞不表达造血细胞系的标志(CD34、CD45、CD14)及内皮细胞的标志(CD106),强表达CD29、CD44、CD13。结论样本量、首次换液时间、胎龄、培养基的质和量对MSCs的成活、生长有关键作用。  相似文献   
60.
Spatial-temporal regulation of bone morphogenetic protein (BMP) and Wnt activity is essential for normal cardiovascular development, and altered activity of these growth factors causes maldevelopment of the cardiac outflow tract and great arteries. In the present study, we show that SOST, a Dan family member reported to antagonize BMP and Wnt activity, is expressed within the medial vessel wall of the great arteries containing smooth muscle cells. The ascending aorta, aortic arch, brachiocephalic artery, common carotids, and pulmonary trunk were all associated with SOST expressing smooth muscle cells, while the heart itself, including the valves, and more distal arteries, that is, pulmonary arteries, subclavian arteries, and descending aorta, were negative. SOST was expressed from embryonic day 15.5 up to the neonatal period. SOST expression, however, did not correspond with inhibition of Smad-dependent BMP activity or beta-catenin-dependent Wnt activity in the great arteries. Activity of both signaling pathways was already down-regulated before induction of SOST expression.  相似文献   
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