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101.
股后区主要穿支的形态学分析与皮瓣设计 总被引:2,自引:1,他引:2
目的:为股后区穿支皮瓣的临床应用提供解剖学依据。方法:6具(12侧)动脉灌注明胶.氧化铅混悬液的新鲜成人整尸标本,解剖观测股后区外径≥0.5mm的穿支,测量其管径及其走行、分支与分布情况等。取下整个下肢被覆组织拍摄X线片,观测皮动脉的数量以及彼此间的吻合情况等。利用Photoshop与Scion Image分析穿支供血的趋向性及每个分支的供血面积等。结果:股后区共有穿支(外径≥0.5mm)27支,其中65%为皮穿支,35%为肌皮穿支。平均外径为0.8mm,平均蒂长为2.93cm。自股深动脉之穿动脉发出者平均长度为6.81cm。每侧穿动脉在股后区供血面积平均为229cm^2,平均每个穿支供血面积为43cm^2。结论:股后区的皮肤穿支管径较粗,营养皮肤面积较大,以股后诸穿支为蒂设计的穿支皮瓣可为下肢或身体其它部位皮肤移植提供:①游离皮瓣;②近端蒂皮瓣;③远端蒂皮瓣。 相似文献
102.
103.
秦巴山区初中学生心理健康状况调查研究 总被引:11,自引:0,他引:11
目的 了解秦巴山区初中学生心理健康状况及其影响的主要因素。方法 采用 SCL-90临床症状自评量表随机对陕西省安康地区双溪乡初中学生进行心理健康测查。结果 秦巴山区双溪乡初中学生心理健康状况与全国初中学生心理健康常模比较 ,并未出现显著性差异 ;影响初中男生心理健康因素从大到小的顺序为 :抑郁 >躯体化 >焦虑 >强迫 >精神病性 >恐怖 >人际关系 >偏执 >其它 >敌对 ;影响女生心理健康因素从大到小的顺序为 :抑郁 >躯体化 >焦虑 >人际关系>强迫 >精神病性 >恐怖 >敌对 >其它 >偏执。结论 秦巴山区初中学生心理健康状况良好。影响秦巴山区初中学生心理健康的最主要因素为 :抑郁、躯体化和焦虑。 相似文献
104.
设计并建立一套连接医学影像采集设备(如CTM、RIP、ET等)、放疗计划系统(TPS)及医用加速器等大型设备的的放射治疗网络体系工作环境,更充分地发挥局域网络在放射治疗中的作用。在现有大型医疗设备、TPS及局域网环境的基础上,提出两种具有代表性的TPS网络体系解决方案,并结合各自的特点及实际应用情况对其进行了分析和比较。实践证明,放疗计划系统网络体系的建设推进了放射治疗全过程的数字化、网络化,在更大范围内实现了医疗信息资源的共享,在更大程度上发挥了TPS在肿瘤治疗过程中的作用。 相似文献
105.
Yasuo Kawakami Kimitaka Nakazawa Toshiro Fujimoto Daichi Nozaki Mitsumasa Miyashita Tetsuo Fukunaga 《European journal of applied physiology》1994,68(2):139-147
Series cross-section images of the upper extremity were obtained for four men by magnetic resonance imaging (MRI) and anatomical cross-sectional areas (ACSA) of elbow flexor muscles [biceps brachii (BIC), brachialis (BRA), brachioradialis (BRD)] and extensor muscles [triceps brachii (TRI)] were measured. Physiological cross-sectional area (PCSA) was calculated from the muscle volume and muscle fibre length, the former from the series ACSA and the latter from the muscle length multiplied by previously reported fibre/muscle length ratios. Elbow flexion/extension torque was measured using an isokinetic dynamometer and the force at the tendons was calculated from the torque and moment arms of muscles measured by MRI. Maximal ACSA of TRI was comparable to that of total flexors, while PCSA of TRI was greater by 1.9 times. Within flexors, BRA had the greatest contribution to torque (47%), followed by BIC (34%) and BRD (19%). Specific tension related to the estimated velocity of muscle fibres were similar for elbow flexors and extensors, suggesting that the capacity of tension development is analogous between two muscle groups. 相似文献
106.
Masanobu Wada Shigeru Katsuta Tokuhide Doi Shin -ya Kuno 《Pflügers Archiv : European journal of physiology》1990,416(6):689-693
Histochemical and biochemical analyses were performed in order to examine the relationship between myosin light-chain (LC) isoforms and fibre-type distributions in whole human skeletal muscle. Muscle biopsies were obtained from the vastus lateralis muscle in six healthy men, and analysed for the relative area occupied by each fibre type (percentage of fibre type area) and the molar ratio of each LC isoform. The percentage of type I fibre area was positively correlated with the molar ratio of slow LC (LC1s and LC2s) to total LC. The regression line was located below the line of unity. Also, the ratio of percentage of type II fibre area to that of type II fibre area was positively correlated with the molar ratio of the fast alkali LC LC1f to fast alkali LCs LC1f and LC3f. These results support previous study, having shown that in human skeletal muscle some type I fibres express various amounts of fast LC in addition to slow LC and suggest that fast myosin heavy-chain HCII a is favourably associated with LC1f, whereas HCIIb is favourably associated with LC3f. 相似文献
107.
von Grünau M. Frost B. J. 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1983,49(1):84-92
Summary For the experiments reported in this study, recordings were obtained from 246 single units in the middle lateral suprasylvian visual area (LS) of 13 cats. 49 of these cells were subjected to detailed quantitative analysis. The receptive field (RF) organization was examined for directionally specific cells by presenting moving single spots on large moving random dot backgrounds. A cell's response to an optimal spot (in terms of size, direction, velocity) moving on a stationary background inside the excitatory RF (ERF) was compared to in-phase (same direction, same velocity) and anti-phase (opposite direction, same velocity) movement of spot and background. In-phase movement resulted in inhibition of the cell's response (3–100%) in 94% of the cells, while anti-phase movement led to reduced inhibition in 52% of the cells or to facilitation (0.5–327%) in 39% of the cells. By changing the direction of background motion with respect to that of the spot, the directional tuning of the in-phase inhibition and anti-phase facilitation effects was determined.We were able to manipulate the size of the background effects by masking out the background for various proportions of the ERF, and maximizing them by restricting background stimulation to the large inhibitory RF (IRF) surrounding the ERF. These results could be best accounted for by a double-opponent-process mechanism with both RF center and RF surround being directionally selective, but with opposite polarity. It is suggested that this type of mechanism could be involved in the processing of object motion.Partially supported by an NSERC University Research Fellowship (U 0057) and an ARC equipment grant to M. von Grünau and by an NSERC Grant to B. J. Frost (A 0353) 相似文献
108.
N. N. Lobanova N. I. Medvedev V. I. Popov A. N. Murashev 《Bulletin of experimental biology and medicine》2008,146(6):691-694
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
109.
110.
Almost all ventromedial hypothalamic (VMH) neurons facilitated by electro-osmotic application of glucose responded to scrotal thermal stimulation. On the other hand, only 50% of neurons which did not respond to glucose responded to the thermal stimulation. The VMH neurons facilitated or inhibited by scrotal warming were mostly facilitated or inhibited by preoptic warming, respectively. These results suggest that thermal signals from scrotal skin and preoptic area were conveyed to VMH neurons, especially to glucose-responsive ones, and could influence feeding control. 相似文献