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101.
102.
It has been reported that sodiumnitroprusside (SNP) decreases mean systemic pressure and simultaneously increases pressure pulse amplification towards the iliac periphery (Kenner and van Zwieten 1982). This unexpected finding was suggested to be due to a decrease in iliac peripheral resistance but an increase in iliac differential resistance. In order to investigate this apparent contradiction, the iliac periphery was hemodynamically isolated from the rest of the circulation and perfused with the dog's own blood by means of a pump. Perfusion pressure (P) and flow (F), femoral venous pressure (Pv), systemic pressure (Ps) and cardiac output (CO) were measured. Steady state pressure-flow relations of the isolated bed were obtained during control and during various i.v. infusion rates of SNP and adenosine (ADS) and were found to be straight (meanr=0.99). Their slope (P/F) was defined as differential resistance (Rd). Peripheral resistance (Rp) of the iliac bed was defined as Rp=(P-Pv)/F, calculated at the flow value where perfusion pressure equalled the prevailing systemic pressure. Total peripheral resistance (TPR) was defined as TPR=Ps/CO. The changes of Rd, Rp, Ps, CO and TPR with respect to control show that during low SNP infusion rates Rd and Rp were both increased while TPR was decreased. During all infusion rates of SNP CO did not change while Ps decreased. During low infusion rates of adenosine CO increased while Ps, Rd and Rp did not change and TPR decreased. During high infusion rates of ADS CO decreased again, Rd, Rp and Ps decreased, and TPR remained constant but at a decreased level.It is concluded that: (1) the suggestion of Kenner and van Zwieten is not supported, since SNP (as well as ADS) affects iliac peripheral and iliac differential resistance in a similar way; (2) SNP (as well as ADS) affects iliac peripheral resistance and total peripheral resistance in a differentiated way, and even in an opposite way during low infusion rates of SNP; (3) it is this opposite effect that explains the paradoxical observations of Kenner and van Zwieten; (4) for comparable reductions of TPR, CO is better maintained during infusion of SNP, while Ps is better maintained during infusion of ADS.  相似文献   
103.
对84例周围血管病(脉管炎68例,静脉炎16例)和25例正常健康人进行了足甲襞微循环的对比观察。结果:患病组足甲襞微循环的血管形态、流态、管周状态均较正常健康组有明显差异(P<0.01)。提示:更接近病变部位的局部微循环观察更能代表病变的程度,对临床医生判断病情、选择用药和疗效观察都有很大帮助和参考价值。  相似文献   
104.
Surface markers were tested on freshly isolated human monocytes and following their in vitro maturation to macrophages. The markers tested were HLA-DR antigens, receptors for the Fc of IgG and complement as well as membrane markers defined by monoclonal antibodies. The results revealed a dynamic expression of some of the markers on monocytes which was influenced by several variables. The expression of the markers was modulated by the presence of different sera, by treatment with lymphokines and interferon and following the in vitro maturation of monocytes to macrophages. The most unstable marker was found to be the HLA-DR, which was modulated by all these variables. The 63D3 was affected by different sera and culture supernatant, as well as following the maturation of monocytes to macrophages, but not by lymphokines and interferon. One of the markers, the Mac 120, was found to be relatively stable and did not change significantly following the maturation of monocytes to macrophages. The Fc and complement receptors were also stable in their expression under these conditions, but were probably partially blocked in the presence of human serum. These results indicated that at least some of the heterogeneity related to the monocyte population was probably not due to the occurrence of stable subsets of cells, but rather to reversible changes in marker expression.  相似文献   
105.
目的:为桡骨交锁髓内钉固定术避免桡神经深支损伤提供解剖学依据。方法:前臂标本44侧解剖显露桡神经深支,将肱骨外上髁与Lister结节连线和桡骨头关节面,关节面下1.0、1.5、2.0cm,桡神经深支穿入旋后肌平面,桡神经深支跨越桡骨平面等6个面的交点,依次标记为A、B、C、D、E、F6个点。记录AE、AF的长度,测量B、C、D3个定点在屈肘前臂旋前、中立、旋后位与桡神经深支的水平距离。结果:B、C、D3个定点离桡神经深支的距离越来越近;而对于同一定点,其与桡神经深支的距离按旋前、中立、旋后位的顺序越来越远。结论:桡骨交锁髓内钉固定时,宜于屈肘前臂中立位,在肱骨外上髁与Lister结节连线上,距桡骨头关节面约1.5cm的位置,由前臂后外侧向前内侧插入远端交锁螺丝钉较为安全。  相似文献   
106.
目的:为带臂外侧上皮神经及其营养血管筋膜皮瓣提供解剖学基础.方法:32例经灌注红色乳胶的成人上肢标本,对臂外侧上皮神经及其营养血管等进行了较详细的应用解剖学研究.结果:臂外侧上皮神经在均由腑神经发出,起点横径为1.5±0.4mm,在三角肌深方斜向外下3.6±1.1cm从该肌后缘中1/3浅出肌间隔,分为上支和下支,分布于三角肌后部、外侧部和臂外侧上部.该神经的营养血管起源于旋肱后动脉,起点外径为0.9±0.4mm;其行程、分支和分布均同在神经,供血范因为14.8×9.8cm~2,并与周围的皮动脉存在丰富吻合.结论:带臂外侧上皮神经及其营养血管筋膜皮 瓣可视受区需要设计成游离瓣或旋转瓣,用于修复邻近部位、手或颌面部缺损.  相似文献   
107.
心率变异性在反映心脏自主神经损伤和重构中的应用   总被引:1,自引:0,他引:1  
缺血预适应和急性心肌梗死恢复期都会出现心脏自主神经的变化,心率变异性(HRV)是无创测量心自主神经活动的重要方法.研究自主神经的变化能为疾病机理和临床用药研究提供理论基础,所以监测预适应和心梗后的HRV有着重要意义.本文综述了预适应和心梗恢复期在HRV上的体现,并将HRV的变化与生理生化证据相联系,分析了缺血预适应对自主神经的保护作用和心梗后用HRV检测自主神经恢复的可行性.同时还对心率变异性今后的研究方向做了展望.  相似文献   
108.
目的:探讨颈脊髓损伤对周围神经功能的影响。方法:对32例脊髓型颈椎病患者分别于术前、术后1~5天及3个月三次检测周围神经传导速度。结果:术前下肢远段感觉神经传导速度和波幅异常者占81%,于术后3个月内复查发现已明显恢复。结论:颈脊髓损伤对下肢远段感觉神经传导功能有影响  相似文献   
109.
Summary A clinicopathological and immunohistochemical study was done on 23 plexiform (multinodular) neurilemomas excised from 20 Japanese. Ages of the subjects ranged from 2 years to 69 years with a mean age of 30 years. The tumours occurred most often on the trunk (14), and were located commonly in the dermis and subcutis (19). Three lesions apparently originated from the peripheral nerve trunks. Multiple tumours were observed in six instances, and two were associated with von Recklinghausen's disease. Microscopically, they appeared as multinodular growths, most nodules were moderately cellular, and both Antoni A and B patterns were distinct in 10 tumours. Obvious Verocay bodies were noted in seven tumours and abortive ones in five. Immunohistochemical reactivity to S-100 protein was demonstrated in both nuclei and cytoplasm of almost all tumour cells of all lesions examined. Recurrences are nil among the 4 patients who could be followed. Correlations with trauma and with von Recklinghausen's disease are briefly discussed.  相似文献   
110.
The objective of this paper is to review the theoretical basis and clinical application of electrical impedance plethysmography in the noninvasive evaluation of peripheral arterial and venous disease. Theoretical, experimental and clinical studies have now demonstrated a direct relationship between electrical impedance changes and limb volume changes. Potential sources of error have also been identified. This has led to the development of clinical tests based on impedance plethysmography for the detection of peripheral arterial disease, venous insufficiency and venous outflow obstruction. Impedance plethysmography, using the method of venous occlusion, is presently the most commonly employed noninvasive method for the detection of deep venous thrombosis.  相似文献   
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