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排序方式: 共有1707条查询结果,搜索用时 24 毫秒
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IntroductionCaloric testing is the most frequently used test to assess peripheral vestibular function since the beginning of the 20th century. However, the video head impulse test, vHIT, has gained prominence in the field of neurotology, as it is a faster examination, easier to perform and less uncomfortable for the patient.ObjectiveTo compare, through systematic review and meta-analysis, the proportion of altered cases between vHIT tests and caloric testing in patients with chronic dizziness, in addition to assessing the sensitivity and specificity of vHIT, with caloric testing as the gold standard.MethodsThe literature search was carried out in the PubMed, Scopus, BVS-Bireme, Web of Science, Embase, Cochrane and ProQuest indexed databases, with no restrictions regarding the publication period. All articles that contained the results of the two tests were included in the evaluation of patients with dizziness. Two researchers independently conducted data selection and extraction from the studies, strictly following the inclusion and exclusion criteria defined in the research protocol. In case of disagreement during the selection, a discussion was carried out with a third evaluator.ResultsEleven of the 1293 initial articles met the eligibility criteria and were analyzed. 2670 patients were evaluated, of which 1112 (41.6%) were males and 1558 (58.4%) females, with a mean age of 51.6 years. The proportion of altered results in the vHIT was 21% (95%CI 9% –33%), and 55% in the caloric testing (95%CI 43% –67%).ConclusionThe vHIT does not substitute for caloric testing. The tests are complementary in assessing the patient with dizziness, as they describe the tonotopy of the ampullary crest at different frequency ranges of stimulation. In chronic cases, the vHIT has a low sensitivity and high diagnostic specificity in comparison to caloric testing.  相似文献   
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Paul L. Booth  W. Eric Thomas   《Brain research》1991,548(1-2):163-171
Ramified microglial cells were investigated in primary cultures of dissociated cerebral cortical tissue from rats. The identification of these cells was confirmed through immunohistochemical staining with 7 monoclonal antibodies selective for microglia. While there was significant variation in staining intensity with different antibodies, all stained the identified ramified cells; the antibodies OX-42 and ED1 yielded the most intense immunoreactivity. Based on distinctive morphological features, the microglia could be identified in living cultures where they were monitored using time-lapse video recording. This technique revealed extremely dynamic features of cellular plasticity and motility. Ramified microglia exhibited constant and rapid alterations in the size and shape of their cell body with an associated extension and retraction of processes; concomitantly, the cells moved about in a circumscribed area. These features of plasticity and motility were unique to this cell type, and correlated with OX-42 immunostaining. The microglia also possessed a differentially high level of pinocytotic activity; this too was correlated with OX-42 staining. From the nature of their morphological plasticity and motility, high pinocytosis, and cellular distribution, it is hypothesized that the ramified microglia specifically function as a system of fluid cleansing in normal brain tissue.  相似文献   
4.
支撑喉镜下射频加囊肿揭盖术治疗会厌囊肿的临床研究   总被引:5,自引:0,他引:5  
目的探讨囊肿揭盖术、囊肿揭盖术+射频、射频+囊肿揭盖术治疗会厌囊肿3种术式的疗效及其优劣。方法57例随机分为3组:单纯囊肿揭盖术组、囊肿揭盖术+射频治疗组及射频+囊肿揭盖术组。3组均采用表面麻醉+强化麻醉经支撑喉镜下手术。随访6-12个月,比较3组总有效率、术中出血量及手术时间。结果3种术式总有效率均为100%,差异无显著性。囊肿揭盖术+射频治疗组、射频+囊肿揭盖术组与对照组比较,术中出血量、手术时间的差异均有显著性;囊肿揭盖术+射频治疗组、射频+囊肿揭盖术组术中出血量、手术时间相比较,差异均有显著性。结论3种术式均是治疗会厌囊肿的有效方法。射频+囊肿揭盖术具有出血更少、手术时间更短、病人痛苦更小等优点,值得临床推广应用。  相似文献   
5.
40例电视胸腔镜手术体会   总被引:2,自引:0,他引:2  
目的 探讨电视胸腔镜(VATS)手术的优点、适应证和手术技巧。方法 回顾总结VATS手术40例。病种有原发性自发性气胸20例,多发性肺大疱3例,Ⅰ期肺癌3例等。手术方式有肺大疱切除23例,肺叶切除术3例(辅助小切口),肺楔形切除4例,纵隔肿瘤切除术3例,结核瘤切除1例,活检3例,胸膜粘连术3例,射频消融1例,纤维板剥脱术1例。结果 本组病例手术时间平均65分钟,失血量少于100ml,中转开胸2例,术后胸液总量平均150ml。胸管置留时间1~7天,平均住院时间7.8天,无气胸、良性肿瘤和结核复发,恶性胸水明显减少或消失,无持续漏气、二次开胸止血和手术死亡等并发症。结论 VATS手术适应证范围较广,微创出血少,美观,恢复快,只要掌握了手术技巧,操作便捷,并发症少,疗效满意。  相似文献   
6.
An image processing system for application to studies of the temporal and spatial parameters of movement during swallowing and speech is described. Image sequences from videotape are digitized for computerized manipulation and analysis in an attempt to improve on conventional visual inspection. The system is “interactive” or “event-driven”: after executing a function, the computer waits for guidance from the user who controls the program through keyboard and mouse input, selecting options from menus and responding to prompts. The analyst alters image clarity by the application of filters and heightens contrast through video enhancement. A technique called “remapping” reduces head motion and provides uniform spatial scaling. Animated sequences of images are used, as opposed to frame-by-frame analysis, to preserve temporal context and increase efficiency of measurement. Low cost off-the-shelf personal computer hardware is used along with original software tailored to the application.  相似文献   
7.
自1994年4月采用内窥镜已行额、面部除皱术22例,取得了较好的临床效果。介绍了应用内窥镜除皱术的操作方法、适应证选择的经验体会。认为在选择好适应证的前提下,是一种简洁的除皱方法。  相似文献   
8.
The effectiveness of fentanyl in attenuating the pressor and heart rate response to orotracheal fibreoptic intubation under general anaesthesia was assessed in 60 healthy patients undergoing elective surgery. Patients were randomly assigned to receive either fibreoptic intubation with or without fentanyl 6 micrograms.kg-1 or traditional Macintosh intubation with fentanyl 6 micrograms.kg-1. A standardised general anaesthetic was administered which included temazepam premedication, thiopentone, atracurium, oxygen, nitrous oxide and isoflurane. The pressor response to fibreoptic intubation was suppressed in those patients who received fentanyl and was similar to that seen in the Macintosh-fentanyl group of patients. The heart rate response to fibreoptic intubation was also significantly reduced in the patients who received fentanyl, but, in contrast, was still significantly greater than that in the Macintosh-fentanyl group. Fentanyl 6 micrograms.kg-1 appears to have a useful place in attenuating the cardiovascular effects of fibreoptic intubation under general anaesthesia.  相似文献   
9.
To assess the curative effects of different reduction techniques on the dislocation of cricoarytenoid joint caused by intubation,indirect laryngoscope (IL) and direct laryngoscope (DL) were utilized for the closed reduction of the displaced arytenoid under local anesthesia.23 patients who underwent the reduction for dislocated arytenoid under IL or DL from January 1991 to June 2001 were reviewed.The data were collected on the duration of the laryngeal injury,times of receiving reduction,side-effects after the treatment and the period for voice to returen to normal.The relationship between the duration of the laryngeal lesion and the period of the voice rehabilitation was examined.13 patients received the reduction under IL and 10 patients under DL,Except the times of the reduction,which showed significant difference,no differences were found between IL group and DL group in the course and the period of voice rehabilitation,as well as sore throat after the manipulation.The patients‘ voice recovery was positively related to their course of disease in both IL and DL group.It is coucluded that the recovery of normal voice is obviously affected by the duration of arytenoid dislocation.The reduction under Il is as effective as under DL in the treatment of arytenoid dislocation.Reduction by DL is better suit the patients with long time course of disease.  相似文献   
10.
电视腹腔镜录像系统在腹部外科临床教学中的应用   总被引:5,自引:0,他引:5  
随着腹腔镜外科的发展,多数腹部外科手术均能在腹腔镜下完成.通过先进的腹腔镜录像系统,可获得大量腹内脏器病变的录像资料.充分利用腹腔镜录像资料进行外科临床教学,可为学生提供真实、形象、生动、全面的疾病相关图像信息,不但可提高学生的学习兴趣,还能让学生更容易理解、掌握所学的知识.  相似文献   
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