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41.
Summary Lengths of muscle tendon complexes of the quadriceps femoris muscle and some of its heads, biceps femoris and gastrocnemius muscles, were measured for six limbs of human cadavers as a function of knee and hip-joint angles. Length-angle curves were fitted using second degree polynomials. Using these polynomials the relationships between knee and hip-joint angles and moment arms were calculated. The effect of changing the hip angle on the biceps femoris muscle length is much larger than that of changing the knee angle. For the rectus femoris muscle the reverse was found. The moment arm of the biceps femoris muscle was found to remain constant throughout the whole range of knee flexion as was the case for the medial part of the vastus medialis muscle. Changes in the length of the lateral part of the vastus medialis muscle as well as the medial part of the vastus lateralis muscle are very similar to those of vastus intermedius muscle to which they are adjacent, while those changes in the length of the medial part of the vastus medialis muscle and the lateral part of the vastus lateralis muscle, which are similar to each other, differ substantially from those of the vastus intermedius muscle. Application of the results to jumping showed that bi-articular rectus femoris and biceps femoris muscles, which are antagonists, both contract eccentrically early in the push off phase and concentrically in last part of this phase.  相似文献   
42.
A new syndrome of triphalangeal thumbs and brachy-ectrodactyly   总被引:2,自引:0,他引:2  
Two Mexican families in which a total of 17 persons exhibited the same pattern of limb malformations are described. The syndrome is characterized by triphalangeal thumbs and brachydactyly affecting the index fingers and the third toes. The clinical findings are variable and the inheritance is autosomal dominant. The syndrome, to the best of our knowledge, has not been described before.  相似文献   
43.
 The purpose of the present study was to examine the effect of maximal arm exercise on the skin blood circulation of the paralyzed lower limbs in persons with spinal cord injury (PSCI). Eight male PSCI with complete lesions located between T3 and L1 performed graded maximal arm-cranking exercise (MACE) to exhaustion. The skin blood flux at the thigh (SBFT) and that at the calf (SBFC) were monitored using laser-Doppler flowmeter at rest and for 15 s immediately after the MACE. The subject's mean peak oxygen uptake and peak heart rate was 1.41 ± 0.22 l · min–1 and 171.6 ± 19.2 beats · min–1, respectively. No PSCI showed any increase in either SBFT or SBFC after the MACE, when compared with the values at rest. These results suggest that the blood circulation of the skin in the paralyzed lower limbs in PSCI is unaffected by the MACE. Accepted: 12 September 1996  相似文献   
44.
45.
The neurochemical identity of ascending putative cholinergic pathways from the rat basal forebrain was investigated employing a method for simultaneously visualizing choline acetyltransferase immunoreactivity and retrogradely transported horseradish peroxidase-conjugated wheatgerm agglutinin. This histochemical procedure revealed three distinct populations of neurons: (1) cells which stained only for choline acetyltransferase immunoreactivity; (2) cells which stained only for retrograde tracer and (3) cells which stained simultaneously for choline acetyltransferase immunoreactivity and retrograde tracer. The results demonstrated that this projection is topographically organized and consists of both cholinergic and noncholinergic components. The relative contribution of each component varied with the telencephalic target area as follows: the olfactory bulb receives a projection from cells of the horizontal limb nucleus, 10-20% of which are cholinergic (Ch3); the hippocampal formation receives afferents from cells of the medial septal and vertical limb nuclei, 35-45% of which are cholinergic (Ch1 and Ch2); and the cortical mantle receives afferents primarily from cells within the substantia innominata-nucleus basalis complex, 80-90% of which are cholinergic (Ch4). The topographical organization of Ch4 projections is not as completely differentiated as we have previously observed in the primate.  相似文献   
46.
In this report we describe the occurrence of severe mesomelic shortening of the forearms due to hypoplasia of the ulnae with severe radial bowing. In contrast to the mesomelic dysplasias, i.e. Langer type of mesomelic dwarfism, this apparently autosomal dominantly inherited skeletal anomaly occurred as an isolated anomaly without concomitant involvement of shanks or other parts of the skeleton, and did not influence final adult height.  相似文献   
47.
We have studied the haemodynamic effects of the application of the medical anti-shock trouser (MAST) in 10 healthy subjects in the semi-upright position in order to simulate mild hypovolaemia. Left ventricular end diastolic dimension (EDD) was measured by M-mode echocardiography and cardiac output (CO) by the Doppler ultrasound technique. Forearm blood flow (FBF) was measured by plethysmography and blood pressure (BP) by the standard cuff technique. Systematic increases in MAST pressure of up to 80 mm Hg were applied. EDD increased to a maximum of 9.3% (p0.01) which was associated with a maximum increase in CO of 31.7% (p0.05). FBF increased by a maximum of 54.2% (p0.001) whilst BP increased by a maximum of 12% (p0.001). These results demonstrate that the application of the MAST is an effective means of transferring blood to the central circulation by compression of the capacitance vessels resulting in significant increases in cardiac output and tissue perfusion. At high pressures there was evidence of compression of resistance vessels, which may be useful in reducing blood loss. The ease and rapidity with which his suit can be applied suggests that it may be useful in the short term treatment of hypovolaemia.  相似文献   
48.
摘 要目的:观察血府逐瘀汤预防上肢皮瓣术后血管危象的临床疗效。 方法:选取 2022 年 1 月至 2023 年 1 月就诊于 赣州市南康区第一人民医院的 60 例行上肢皮瓣转移术的患者,采用简单数字随机法分为观察组和对照组,各 30 例。术后 对照组患者常规应用 “ 三抗 ” 治疗,观察组患者在 “ 三抗 ” 的基础上加服血府逐瘀汤剂,比较两组患者术后皮瓣的血运情 况、总体疗效。 结果:术后 3 d、7 d,观察组患者皮瓣肿胀程度优于对照组,差异具有统计学意义(Z 分别为 –2.28、–3.46, P < 0.05);术后 1 d、3 d、7 d,观察组患者毛细血管反应优于对照组,差异具有统计学意义(Z 分别为 –6.89、–6.29、–7.35, P < 0.05);观察组患者疗效优于对照组,差异具有统计学意义(Z = –3.44,P < 0.05)。 结论:上肢皮瓣术后的患者在常 规 “ 三抗 ” 的基础上,加用血府逐瘀汤可有效减少血管危象的发生,提高皮瓣成活率。  相似文献   
49.
目的 观察后肢体缺血 /再灌注是否诱发心脏血红素氧合酶 1(HO - 1)的表达。方法 在氨基甲酸乙脂麻醉大鼠行后肢体缺血 /再灌注后 ,测量心脏组织中丙二醛的含量和超氧歧化酶 (SOD)的活性 ;并应用Northern和Western杂交方法分别检测HO - 1mRNA和蛋白的表达情况。结果 在肢体缺血 /再灌注过程中 ,心脏中的丙二醛含量增加 ,而超氧歧化酶的活性降低 ;单纯肢体缺血并不引起心脏血红素氧合酶 1mR NA和蛋白表达的变化 ,但缺血 /再灌注增强心脏血红素氧合酶 1mRNA和蛋白表达。结论 肢体缺血 /再灌注不仅提高心脏中丙二醛的含量 ,降低超氧歧化酶的活性 ;而且上调血红素氧合酶 1在心脏的表达。  相似文献   
50.
目的 探讨应用介入方法治疗急性下肢缺血性疾病的临床效果及安全性。方法 21例患按基础病因不同分为两组,对无患肢慢性缺血史给予单纯动脉内灌注尿激酶,对存在有患肢慢性缺血史在给予适当尿激酶30万u后,应用超滑导丝通过闭塞段,顺导丝送入球囊导管行PTA术。结果 第1组8例,获得成功,1例于术后第3天死于急性左心功能不全;第2组9例获得成功,3例在发病5日后行截肢术。结论 (1)多种介入方法联合治疗急性下肢缺血临床效果可靠。(2)基础性病因是决定介入方法选择的首要因素。  相似文献   
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