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31.
头低位模拟失重状态对前庭功能的影响   总被引:4,自引:1,他引:3  
为研究头低位模拟失重对运动病症状、垂直视动眼震(VOKN)及体液重新分配的影响,在头低位-10°的模拟失重状态下,采用大视野的垂直视动刺激,观察18名正常人的运动病症状、VOKN、激素(AVP、VIP、CORT、ALDO)的反应特点。结果表明,头低位-10°状态下的大视野垂直视动刺激可以诱发出明显的运动病症状,头低位-10°的垂直视动刺激比坐位更容易诱发运动病。坐位状态VOKN慢相速度有明显的方向性不对称,敏感组VOKN方向性不对称有显著差异(P<0.05)。头低位-10°时VOKN的不对称现象不明显,向下方向运动的VOKN慢相速度显著增加。分析指出,头低位-10°状态下垂直视动刺激比坐位和秋千刺激的贡献率大。尿中CORT(皮质醇)在秋千和头低位的垂直视动刺激前后有显著性增加。提示:大视野的垂直视动刺激与头低位-10°两种刺激的结合可能成为预测空间运动病的方法之一.  相似文献   
32.
本文比较了11例眼球异物CT与X线影像,并经手术摘出异物证实,CT眼球异物检出及定位准确性均优于X线,尤其对球壁异物的定位,而且能显示断层眼球壁轮廓,具有直观效果,CT异物影像比异物明显扩大,应警惕CT伪影可能使球壁异物定位发生误差,CT目前尚不能完全取代眼球异物常规X线检查。  相似文献   
33.
A large animal model is needed to evaluate new apheresis technologies. These technologies include novel methods of harvesting the blood mononuclear cell population which contains the hematopoietic stem cells needed to restore hematopoiesis in recipients of hematopoietically lethal therapy and the use of cytokines to provide a safe and predictable method of manipulating these circulating hematopoietic stem cells. We describe the methods used to collect mononuclear cells by leukapheresis from Yucatan miniature swine. These animals are of sufficient size to tolerate the procedures and have many physiologic and hematologic similarities to man. They are of good temperament and are easily trained. Long-term venous access was obtained using single lumen silicone rubber catheters placed in the inferior vena cava. The animals were apheresed while fully awake using a Haemonetics Model V50 machine and a modified lymphocyte collection protocol. The procedure was highly efficient for the collection of mononuclear cells and a 10 pass procedure yielded a product which contained 19.7 × 109 mononuclear cells, 10.7 × 109 granulocytes, and 17 ml of erythrocytes in a volume of approximately 100 ml. This product can be cryopreserved and used for subsequent transplantation. The content of four apheresis procedures provides hematopoietic reconstitution of lethally irradiated swine on a time scale equivalent to transplantation of optimal numbers of bone marrow cells. © 1992 Wiley-Liss, Inc.  相似文献   
34.
Cytokines are involved in fever and other symptoms of the acute phase response induced by endotoxins. The aim of this work was to study the involvement of central tumour necrosis factor-alpha (TNF-alpha) in the changes induced by lipopolysaccharide (LPS) on gastrointestinal (GI) motility in sheep. Body temperature and myoelectric activity of the antrum, duodenum and jejunum was recorded continuously. Intravenous (i.v.) administration of LPS (0.1 micro g kg-1)-induced hyperthermia, decreased gastrointestinal myoelectric activity and increased the frequency of the migrating motor complex (MMC). These effects started 40-50 min after LPS and lasted for 6-7 h. TNF-alpha (50 and 100 ng kg-1) mimicked these effects when injected intracerebroventricularly (i.c.v.) but not i.v. Pretreatment with soluble recombinant TNF receptor (TNFR:Fc, 10 micro g kg-1, i.c.v.) abolished the TNF-induced actions and reduced those evoked by LPS. Furthermore, the effects induced by either LPS or TNF were suppressed by prior i.c.v. injection of indomethacin (100 micro g kg-1). In contrast, the i.v. injections of TNFR:Fc or indomethacin were ineffective. Our data suggest that LPS disturbs GI motility in sheep through a central pathway that involves TNF-alpha and prostaglandins sequentially.  相似文献   
35.
One hundred and fifteen patients, between 6 months and 12 years of age, had bronchoscopy on suspicion of foreign body aspiration. The histories of these patients were studied to examine the diagnostic value of signs, symptoms and examinations, and to determine the time that passed between aspiration and removal of the foreign body. The sensitivity of the symptoms choking and coughing was fairly high (81 and 78%), but the specificity was poor. The sensitivity of a chest radiograph was 82%, the specificity 44%. The sensitivity of radiographs on inspiration and expiration was 80%, the specificity 55%. The patients had been referred with the initial diagnosis foreign body aspiration (80), pneumonia (34), or subglottic laryngitis (1). In 85 patients a foreign body was identified and extracted. The other 30 patients had respiratory tract infections. The initial diagnosis of foreign body aspiration was correct in 61 out of 85 patients. In these cases, the period between aspiration and extraction of the foreign body was a mean 6 days, compared with 55 days, if the initial diagnosis was pneumonia or sub-glottic laryngitis. We conclude that the diagnosis of foreign body aspiration is too often missed, and that, apart from bronchoscopy, diagnostic tools are of little value.  相似文献   
36.
Abstract: The Self-Rating Body Image (SRBI) test was used to determine whether the patients with eating disorders such as anorexia nervosa or bulimia showed their body image disturbance or not. The SRBI was completed by 120 subjects who consisted of 30 low weight (LW) controls, 30 normal weight (NW) controls, 30 high weight (HW) controls, 18 anorexic patients (AN) and 12 bulimic patients (BN). The AN group had a significantly greater dissatisfaction with the scales of the body shape, visceral organ and face image of the SRBI than the weight-matched LW group. The BN group had a significantly greater dissatisfaction with the visceral organ image than the weight-matched NW group. However, no significant difference in the body shape and face images between the BN and NW groups was found. Our results suggest that the anorexic patients may disturb more parts of the body image than the bulimic patients though both the anorexic and bulimic patients showed the disturbance of body image.  相似文献   
37.
Ask the Expert provides research‐based answers to practice questions submitted by JSPN readers.  相似文献   
38.
During the early stages of nerve implantation, we followed the dynamic properties of the lateral gastrocnemius muscle of the rat, reinnervated with an acutely or chronically severed peroneal nerve. The aim of this study was to ascertain whether (1) the better functional recovery of a muscle reinnervated by a chronically severed foreign nerve is present from the onset of reinnervation, and (2) whether such functional improvement is due to the conditioning lesion effect. Our results indicate that better functional recovery is already apparent one week after nerve implantation, and it is due to the conditioning lesion effect, since tenotomy prevents such improvement. The tenotomy effect underlines the fact that some environmental factors concerning the target tissue, and not only the predegenerated nerve, are involved in the conditioning effect. © 1995 Wiley-Liss, Inc.  相似文献   
39.
闻祥根  董启云 《眼科学报》1993,9(4):216-218,185
眼内异物合并外伤性白内障是眼外伤常见的致盲原因之一,各地报告的致盲率为20%~48.9%。本文对88例眼内异物合并外伤性白内障患者采用联合手术治疗,收到较好疗效,术前视力0.05以下占85.2%,术后矫正视力0.05以下占27.3%,矫正视力0.06~1.5占73.7%,其中矫正视力0.6~1.5者占22.8%。根据异物的性质、在眼内部位和晶体损伤情况选择不同的手术方式一次联合手术摘出异物和白内障,术后采用中西药配合治疗。联合手术可提高疗效,减少术后并发症.减少手术次数,减轻病人的痛苦,缩短病程,减少医疗费用.眼科学报1993;9:216—218.  相似文献   
40.
A cerebral type of Lewy body disease (LBD) is proposed. Lewy body disease was split formerly into three types: brainstem type, transitional type and diffuse type. The diffuse type is now called diffuse Lewy body disease (DLBD). These three types are characterized pathologically by the presence of a large number of Lewy bodies in the CNS. In the brainstem type, Lewy bodies are numerous in the brainstem and diencephalon nuclei, and in DLBD, a vast number are present not only in these nuclei but also in the cerebral cortex and amygdala. In the cerebral type of LBD, as many Lewy bodies are found in the cerebral cortex and in the amygdala as there are in DLBD, but only rarely are they present in the brainstem and diencephalon nuclei. Thus, this type of LBD is different from other types in that it has no parkinson pathology. Therefore, parkinsonism fails to occur throughout the whole clinical course of this disease. The existence of a cerebral type of LBD suggests that Lewy bodies occur in the cerebral cortex earlier than in the brainstem nuclei and that cortical Lewy bodies appear even when the mesocortical dopaminergic system is intact. In addition, this might explain why dementia frequently precedes parkinsonism in DLBD.  相似文献   
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