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101.
Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: Intravenous infusion 总被引:2,自引:0,他引:2
Peter P. C. Tan Ming-Hwang Shyr Chen-Hsein Yang Terry B. J. Kuo Wynn H. T. Pan Samuel H. H. Chan 《Neuroscience letters》1993,160(2):205-208
Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that effective antinociception could be achieved in adult male Sprague-Dawley rats 15 min after intravenous infusion of propofol at 60 mg/kg/h. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant depression of the activity of all EEG frequency bands (δ, θ, , β), alongside hypotension, negative inotropic and chronotropic actions, and attenuated baroreceptor reflex and vasomotor activity. These effects were congruent with a plasma concentration of propofol in the arterial blood of 1.70 ± 0.13 μg/ml, as determined by high-performance liquid chromatography. 相似文献
102.
J
RGEN THORVALDSON ARNFINN ILEBEKK SEVERIN LERAAND FREDRIK KIIL 《Acta physiologica (Oxford, England)》1984,121(1):45-56
To examine the effects of pulmonary vascular pressures and flow on pulmonary blood volume (PBV), experiments were performed at constant heart rate and zone 3 conditions (mean left atrial pressure (LAP) above airway pressure) in six anesthetized, open-chest dogs. PBV was calculated as the product of electromagnetic aortic flow and pulmonary mean transit time for ascorbate, obtained without blood withdrawal by polarographic recording of aortic ascorbate changes. In three series of experiments LAP was raised similarly in three steps, from 4.5 to 14.8 mmHg: by mitral constriction which reduced pulmonary blood flow, by blood volume expansion which more than doubled pulmonary blood flow, or by a combination of the two procedures which kept pulmonary blood flow constant. In all three series, LAP and mean pulmonary arterial pressure (PAP) rose in proportion, but PBV was better correlated to PAP (r=0.87±0.02) than to LAP (r=0.66±0.09). These experiments suggest that PAP is the most important factor in determining PBV under zone 3 conditions, whether PAP is raised by increasing pulmonary blood flow or by mitral constriction. 相似文献
103.
目的:为动脉造影术以及对病变脏器进行化学治疗时的导管插入提供解剖学依据。方法:用不锈钢尺测量从股动脉起始处至冠状动脉起始处全程中主动脉各主要分支的距离;用游标卡尺测得各动脉起始部的外径。结果:从左、右股动脉起始处,经髂外动脉、髂总动脉最终到左冠状动脉起始处之间的长度分别为(68.9±4.2)cm和(69.0±3.9)cm;到右冠状动脉起始处之间的长度分别为(68.3±4.0)cm和(68.5±3.6)cm。左、右冠状动脉起始处的外径分别为(6.2±1.3)mm和(5.0±0.8)mm。结论:本文的测量数据可供经股动脉至冠状动脉起始处全程中主动脉的各主要分支施行心导管诊断治疗和对内脏器官的疾病进行化学治疗以及局部脏器动脉造影术参考。 相似文献
104.
Macchi V Tiengo C Porzionato A Stecco C Parenti A Mazzoleni F Ger R De Caro R 《Clinical anatomy (New York, N.Y.)》2005,18(8):580-588
The abductor hallucis muscle flap is commonly used as a proximally-based flap in the management of ankle, heel, and midfoot lesions, where it is ideally suited for closing defects. This study investigates the anatomical details of this muscle in 13 fresh male cadavers. The medial plantar artery (MPA) was studied by dissection and macroscopic analyses to document the relationship of its superficial and deep branches with respect to the abductor hallucis muscle (AHM). Three main patterns could be described. In Pattern A (54%) the MPA divides into two branches. The deep branch reaches the deep surface of the AHM, supplying its proximal part, and the superficial branch courses between the AHM and the flexor digitorum brevis, to end as the first plantar metatarsal artery. The latter supplies two to three small branches to the distal part of the AHM. The fibers of the AHM end symmetrically on the two sides of the tendon and the muscle presents an arciform shape. The MPA, in Pattern B (38%), lacks a deep branch and continues along the lateral border of the AHM as a superficial branch that supplies proximal and distal collaterals to the muscle. The muscle fibers of the AHM end mainly on the medial side of the tendon. The muscle belly presents an arciform shape and is located on the medial margin of the foot superomedially with respect to Pattern A. In Pattern C (8%) the MPA continues as a large deep branch on the deep surface of the AHM and ends as the medial collateral artery of the big toe. A smaller superficial branch of the MPA provides a few collaterals to the AHM from its proximal part and to the flexor digitorum brevis in its distal part. The AHM fibers end mainly on the lateral side of the tendon and morphologically the muscle presents a straight line on the sole of the foot compared to Pattern A. Although Patterns B and C, from a surgical point of view, necessitate interruption of the main trunk of the MPA, Pattern A may permit the vascularization of the muscles of the medial side of the sole of the foot by the superficial trunk of the MPA. Because preoperative radiological study of the plantar vessels correlate with the morphological characteristics of the AHM observed during surgery, such imaging may be useful in determining the appropriate flap design based on the patient's unique pattern of MPA branching. 相似文献
105.
冠状动脉血管直径测量方法的研究 总被引:1,自引:0,他引:1
心脏是人体生命活动的重要器官,能否正常工作主要是由心血管系和心传导系决定。冠状动脉是给心脏供血的唯一途径,心肌能否得到足够的营养、保持连续有节奏地运动,完全取决于冠状动脉是否能不断地供给其营养。冠状动脉直径的测量以及血管直径参数对于反映心脏功能和疾病的诊断具有重要意义。文中提出一种新型的、简便的血管直径测量方法,利用计算得到的血管直径,我们就可以判别心血管狭窄位置。 相似文献
106.
G. S. Yakobson A. R. Antonov G. V. Petrova L. N. Maslova A. L. Markel' 《Bulletin of experimental biology and medicine》1996,121(5):449-451
Endocrine functions were investigated in normotensive (Wistar) and hypertensive (NISAG) rats before and on days 3, 7, and
21 after subcutaneous epinephrine administration. Rats of the NISAG strain are characterized by elevated plasma levels of
aldosterone and thyroxine and lowered plasma levels of immunoreactive insulin, and their endocrine system develops a much
stronger response to a single epinephrine injection than does that of Wistar rats. This is manifested in a still higher aldosterone
level, elevated corticosterone and insulin concentrations, and reduced thyroxine content in the plasma.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 495–498, May, 1996 相似文献
107.
Satoru Honma Akinari Tokiyoshi Katsushi Kawai Masahiro Koizumi Kodo Kodama 《Anatomical science international / Japanese Association of Anatomists》2008,83(4):232-238
A radial artery running beneath the biceps tendon was found in the cadaver of a Japanese woman during a student dissection
course at Kumamoto University School of Medicine in 2006. The brachial artery bifurcated into the radial artery and the ulnar
artery in the cubital fossa, and the radial artery twisted laterally running beneath the biceps tendon, and when it was situated
laterally to the tendon, twisted distally at the level of the radial tuberosity, and then twisted medially again. After the
radial artery passed over the biceps tendon, it turned distally and continued as a normal radial artery. The superficial brachial
artery, which coexisted with the brachial artery, was given off from the axillary artery and it continued to the final twist
of the radial artery. The course of this radial artery is similar to the arterial rings surrounding the biceps tendon, found
during the same dissection course. The arterial rings were formed between the brachial artery and the radial artery, and their
proximal origins ran beneath the biceps tendon, while the distal origins were superficial. The present arterial variation
is thought to have occurred when the normal part of the radial artery in the cubital fossa was substituted by the arterial
ring, coexisting with the superficial brachial artery, which usually disappears during normal development. Furthermore, it
is suggested that a part of the arterial ring always remains as a radial recurrent artery. 相似文献
108.
目的研究踝臂指数(ABI)在下肢外周动脉病患者治疗前后的变化作为评价指标的可行性.方法下肢外周动脉病患者116例,分为2组:A组(单纯药物治疗组)77例.其中男性46例,女性31例.平均年龄(67±8)岁;B组(介入治疗+药物治疗组)39例,其中男性22例,女性17例,平均年龄(65±5)岁。详细记录每一患者的临床资料,包括年龄、性别、身高、体质量、心率、血压、空腹血糖、血脂等.并分别于治疗前、治疗后1个月、治疗后3个月检测ABI。结果①下肢外周动脉病患者治疗前ABI〈0.90:②B组治疗后1个月和治疗后3个月的ABI与治疗前相比差异均有统计学意义(P〈0.05);③A组治疗后1个月和治疗后3个月的ABI与治疗前相比无明显变化(P〉0.05)。结论ABI在下肢外周动脉病患者的治疗中可起重要的指导作用.介入治疗能够及早改善下肢外周动脉病患者的血运.比单纯药物治疗疗效显著。 相似文献
109.
作为文章[1]的继续,本文在文章[1]的分析结果基础上,针对壁面对称和非对称狭窄的两种不同情况,通过数值计算给出弯曲狭窄血管内血流的轴向和周向切应力的分布曲线,并讨论其随管壁面几何参数的变化情况。同时,还讨论壁面几何参数对平均血流量和压力降影响的规律。从中发现,当狭窄较轻时(λ<0.2),壁面切应力、平均流量和压力降受狭窄度(λ)的影响不大,而在狭窄较严重时(λ>0.7),狭窄度微小的变化会引起它们急剧变化。此外,在讨论狭窄的非对称性对上述血流动力学参数的影响时还发现,非对称性只对轴向切应力有明显的影响,而对其它参量的影响并不十分显著。 相似文献
110.
Tkachenko BI Evlakhov VI Poyasov IZ 《Bulletin of experimental biology and medicine》2003,136(3):213-215
Experiments on cats treated with nitroglycerin showed dynamic relationship between changes in caval venous flows: blood flow increased in the superior vena cava and decreased in the inferior vena cava. Blood pressure in the right atrium either decreased, or increased. No significant changes in total venous return were observed during maximum shifts in right atrial pressure, while contractility of the right ventricular myocardium usually decreased. Our findings suggest that the direction of the right atrial pressure shifts induced by nitroglycerin does not depend on venous return, but is determined by the prevalence of flow changes in the superior vena cava or inferior vena cava. 相似文献