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101.
Frank Queisser Ralph Blüthner Dieter Bräuer Helmut Seidel 《European journal of applied physiology》1994,68(1):92-101
A group of 12 healthy men volunteered for the experiment. Electromyograms (EMG) were obtained from semispinalis capitis, splenius capitis, levator scapulae, and trapezius muscles. The flexion angle of the cervical spine was precisely adjusted to 0°, 10°, 20°, and 30° relative to the horizontal, with a constant angle of the atlanto-occipital joint. The subjects made eight short (about 2 s) vertical extension forces (6%, 12%,18%, 24%, 30%, 36%, 42%, and 48% of maximal voluntary peak contraction force). For each position, the centre of pressure under the head was determine as the basis for the calculation of the external lever arm. The presence of motor endplate regions was ascertained by multiple surface electrodes. The slopes of individual linear regression lines for the root mean square (rms)-values were dependent on the existence of endplates in the area of the electrodes — endplates caused smaller rms values per Newton metres of external torque. Significant intersubject differences between regression equations could not be eliminated by the normalization of EMG-parameters and/or torques. The elimination of gravity, the continuous monitoring of positions, and the consideration of localization of motor endplate regions were essential prerequisites for the acquisition of reliable relationships between EMG of different neck muscles and external torques. Two important conclusions were derived for the prediction of torques from EMG measurements: firstly, individual regression equations which take into account the position of the head and neck should be used; secondly, normalization procedures do not justify the application of average regressions to a group of subjects. 相似文献
102.
颞骨内面神经管的解剖测量及其临床意义 总被引:3,自引:0,他引:3
目的为避免中耳手术中对面神经的损伤。方法对50例(100侧)成人尸头颞骨内面神经管进行解剖测量。结果面神经管迷路段为4.53±1.21mm,鼓室段为9.32±1.25mm,乳突段为13.25±1.53mm,面神经管总长为29.86±0.57mm。结论熟悉颞骨内面神经管的解剖结构,可避免对面神经的损伤,减少和避免面瘫的发生。 相似文献
103.
M Z SATTI P LIND B J VENNERVALD S M SULAIMAN A A DAFFALLA H W GHALIB 《Clinical and experimental immunology》1996,106(1):45-54
The present work comprises a longitudinal study of Schistosoma mansoni infection in occupationally hyper-exposed canal cleaners in the Sudan and the influence of chemotherapy on humoral immune parameters. The study groups included chronically infected canal cleaners (n = 19), newly recruited canal cleaners (n = 17), normally exposed adults (n = 31), school children (n = 46) and Sudanese negative controls (n = 48). Previous studies of the same canal cleaners have demonstrated that chronically infected canal cleaners were more resistant to reinfection than newly recruited canal cleaners. ELISA was used to detect specific IgE and IgG subclasses in response to whole worm antigen (WWH) and soluble egg antigen (SEA) before and 3 months after praziquantel treatment in the groups of canal cleaners and before and 1 year after treatment in normally exposed adults. When intensity of infection was correlated with IgE antibody response, the resistant group of canal cleaners (those who stopped passing ova after treatment) showed a significant positive correlation between intensity of infection and specific IgE to WWH (Spearman''s correlation coefficient = 0·49, P < 0·05) compared with a highly significant negative correlation in the susceptible group (acquired new infection after treatment, Spearman''s correlation coefficient = 0·94, P < 0·01). Normally exposed adults and school children had significantly less specific IgE to WWH than canal cleaners, while chronically infected canal cleaners had significantly higher levels of specific IgG1 to WWH than newly recruited canal cleaners and school children, and significantly higher levels of specific IgG4 to WWH than school children. There was a significant increase in specific IgG1 and IgG4 to WWH, 3 months after treatment, in newly recruited canal cleaners and a significant decrease, 1 year after treatment, in normally exposed adults. None of the groups studied after treatment showed a significant change in their specific IgE to WWH. Normally exposed adults had significantly lower levels of specific IgE to SEA than newly recruited canal cleaners, and significantly lower levels of specific IgG1 to SEA than other infected groups. Both newly recruited canal cleaners and school children had significantly higher levels of specific IgG2 to SEA than persons in other groups. Only small differences between groups were observed with regard to specific IgG3 and IgM to SEA. Specific IgG4 to WWH and SEA showed different patterns after treatment between the resistant and susceptible groups of canal cleaners. The resistant group maintained the same level of IgG4 to WWH after treatment compared with a significant increase in the susceptible group. On the other hand, levels of specific IgG4 to SEA showed a highly significant decrease after treatment in the resistant group. In contrast, the same antibody subclass increased after treatment in the susceptible group. Generally, results show an association between IgE and IgG1 responses to WWH and resistance to reinfection. In contrast, an association was observed between IgG2 and IgM responses to SEA and susceptibility to reinfection. 相似文献
104.
Summary Seventy-one Caucasian orbits (36 right, 35 left) were studied by dissection. The diameter of the ophthalmic a. (2 mm from the origin) was 1.54 ± 0.04 mm (male) and 1.31 ± 0.05 mm (female). In individual cases, there were no significant differences in vessel diameter between the right and left sides but, differences in vessel diameter between males and females were more commonly observed in the arteries which leave the orbit (extraorbital group), the individual vessels having a larger diameter in males. The incidence of the ophthalmic a. passing in the orbit medially under the optic n. was 18.6%. The lacrimal a. was observed to arise from the ophthalmic a. in only 82.5% of the cases examined, 15.9% of the cases showed the origin to be at the anastomotic branch of the middle meningealThis article is dedicated to Pr Dr Hoepke on occasion of his 100th birthday 相似文献
105.
在80侧成人颞骨干标本上,对面神经锥体段的埋藏位置及深度,面神经与面神经隐窝、鼓室窦三者之间的关系及其变异类型进行了应用解剖学研究。提出了耳科后鼓室进手术路中对面神经锥体段的予测方法。经90例手术验证有实用价值。 相似文献
106.
Y. Uchino N. Isu T. Ichikawa S. Satoh S. Watanabe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1988,71(2):345-352
Summary Unit activites of secondary vestibular neurons that selectively responded to stimulation of the anterior semicircular canal nerve (ACN) were recorded extracellularly in the anesthetized cat. Axonal pathways and projections in the spinal cord of the ACN-activated neurons were examined by recording their antidromic responses to stimulation of the lateral and medial vestibulospinal tracts (LVST and MVST), and the bilateral neck extensor motoneuron pools in the C1segment (C1dorsal rami [DR] motoneuron pools). In order to determine whether the neurons had ascending axon collaterals to the extraocular motoneurons, the contralateral (c-) inferior oblique (IO) motoneuron pool was also stimulated. Twenty-seven neurons sent their axons to the ipsilateral (i-) C1DR motoneuron pool via the LVST without any projection to the extraocular motoneuron pool. All the cells except one were located in the ventral part of the lateral vestibular nucleus. This pathway produced monosynaptic EPSPs with short time-to-peak and short half-width in C1DR motoneurons (16/16 motoneurons). Eight neurons sent axons to the i-C1DR motoneuron pool via the MVST without any to the extraocular motoneuron pool. Cell somata were located in the descending nucleus or in the ventral part of the lateral nucleus. These neurons did not produce postsynaptic potentials (PSPs) in any C1DR motoneurons. All thirty-five neurons sending axons to the c-C1DR motoneuron pool have ascending axon collaterals to the c-IO motoneuron pool. 相似文献
107.
舌下神经管及其毗邻结构的显微解剖和临床意义 总被引:2,自引:0,他引:2
目的:研究舌下神经管及其毗邻结构的显微解剖,为舌下神经管疾病的影像学诊断和手术入路的选择提供形态学数据。方法:肉眼和手术显微镜下观测30例(60侧)成人头颅干骨标本的舌下神经管及其毗邻结构。结果:舌下神经管位于枕骨髁的前上方,为一对卵圆形或圆形孔道,内口至外口的长度(8.51±0.91)mm。舌下神经管内口呈双管者5侧(8%);内口后缘与枕骨髁后缘的距离(10.07±0.75)mm,外口后缘至枕骨髁后缘(14.22±1.18)mm。左、右侧枕骨髁的前后径分别为(23.10±1.57)mm、(22.38±2.28)mm。结论:熟悉舌下神经管及其毗邻结构的解剖有利于相关疾病的影像诊断和手术入路的选择。 相似文献
108.
P. Vergnes D. Midy J. M. Bondonny H. Cabanie 《Surgical and radiologic anatomy : SRA》1985,7(4):257-265
Summary This paper begins with a review of the embryology of the inguinal region. The authors then point out the special morphological and topographical features of the inguinal canal in male children. These observations were based on the study of 50 inguinal canals from male children. From the anatomical observations described in this study guidelines are proposed for the surgical approach and dissection of the spermatic cord used in the treatment of congenital hernias or abnormal descent of the testis.
Bases anatomiques de la chirurgie inguinale de l'enfant
Résumé Après une étude embryologique de la région inguinale, les auteurs décrivent les particularités morphologiques et topographiques du canal inguinal en croissance de l'enfant de sexe masculin, se basant sur l'étude de 50 cas. De ces notions anatomiques découlent des règles chirurgicales sur la voie d'abord et la dissection du cordon spermatique lors des cures de hernies congénitales ou d'anomalies de migration testiculaire.相似文献
109.
Clinical, parasitological and immunological features of canal cleaners hyper-exposed to Schistosoma mansoni in the Sudan 下载免费PDF全文
M Z SATTI S M SULAIMAN M M A HOMEIDA S A YOUNIS H W GHALIB 《Clinical and experimental immunology》1996,104(3):426-431
The present work was a longitudinal study on Schistosoma mansoni infection in occupationally hyperexposed canal cleaners in the Sudan and the influence of therapy on the parasitological and humoral immune parameters. Chronically infected canal cleaners (n = 28) were more resistant to reinfection (Fisher's exact test, P < 0.05) than newly recruited canal cleaners (n = 17). Chronically infected canal cleaners had a significantly higher degree of Symmers' fibrosis (χ2 = 19.1, P < 0.0001), significantly larger portal vein diameter (P < 0.05) and enlarged spleen (χ2 = 4.2, P < 0.05) than recently infected, newly recruited canal cleaners. ELISA was used to detect IgG, IgA and IgM in response to whole worm homogenate (WWH) and cercarial homogenate (CH). Chronically infected canal cleaners had significantly higher IgG to WWH antigen than newly recruited canal cleaners and normally exposed individuals (P < 0.05), while both chronically infected and newly recruited canal cleaners had higher IgG levels to CH antigen than normally exposed individuals (P < 0.05). The newly recruited canal cleaners had a significantly higher IgM level to CH antigen than chronically infected canal cleaners (P < 0.05). The IgG level to WWH antigen increased significantly after treatment in newly recruited canal cleaners and normally exposed individuals (P < 0.05). The IgA level to CH antigen increased significantly after treatment in the chronically infected group (P < 0.05). Comparison of the serological parameters between the different study groups with regards to infection and treatment is discussed. 相似文献
110.
目的:评估iRoot SP在不可复性牙髓炎中根管填充后出现疼痛情况。方法:选取本院不可复性牙髓炎患者80例,按随机数字表分为两组,在常规根管治疗后,试验组及对照组分别采取iRoot SP及AH Plus进行填充,利用VAS评分对比两组患者不同时间点出现不同疼痛分级的患者比例、疼痛程度及因疼痛口服布洛芬比例。结果:术后12h试验组呈现无痛的患者比例较对照组明显更高(21vs10,P=0.012),术后24h试验组出现重度疼痛比例较对照组明显更低(0vs6,P=0.034)。与对照组相比,iRoot在不同时间段均能有效降低患者术后疼痛程度(P<0.001)。然而两组患者因疼痛口服止痛药比例无明显差异。结论:iRoot SP可以明显降低不可复性牙髓炎患者根管治疗后早期出现疼痛机率及疼痛严重程度。 相似文献