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41.
Out of 50 children (100 ears) undergoing adeno-tonsillectomy, 34 ears had hearing threshold 20–50 dB (20dB is normal) and 32 ears showed negative middle ear pressure of 100 to 400 mmH2O (100 mmH2O is normal). Post-operatively only 7 ears had hearing threshold of 20–30 dB and negative middle ear pressure of 100 to 200 mmH2O. Thus adenoidectomy improves eustachian tube functions.  相似文献   
42.
Of 613 children evaluated in a village in Haryana 94 (15.3%) were observed to have chronic suppurative otitis media (CSOM). Fifty eight (61.7%) children had hearing impairment. CSOM contributed to 71.6% of the hearing impaired (58/81). On analysis of association of CSOM with literacy and socio-economic status of mothers, and age, sex, and upper respiratory tract infections (URI) in children positive correlation was observed only with URIs (P<0.001). Literacy and socio-economic status of the mothers did not correlate significantly with knowledge about treatment seeking, and ear cleaning practices, probably due to the narrow range of incomes and literacy levels. An intervention program consisting of play, demonstrations, health charts and slogans, and aural cleaning and antibiotic drops was introduced.  相似文献   
43.
A pulsed holmium: YAG laser ( = 2120 nm) was used to reopen the basal turn of artificially obliterated human cochleas in freshly dissected cadavers. This allowed intracochlear insertion of the stimulation electrode of a cochlear implant under simulated surgical conditions. Laser energy was transmitted through a 400-m nylon fiber via the opened facial recess directly to the round window niche. At an energy level of 500 mJ per 2.5 s pulse, a repetition rate of 2 Hz, and an exposure time of 20–30 s, the photo-ablative mechanism of laser-bone interaction led to a 8–10 mm recanalization of the basal turn of the cochlea without damaging surrounding structures. The artificial bony occlusion and the recanalized basal turn of the cochlea were visualized by means of computed tomography and studied under light microscopy, using a histologic thin-section technique.Presented at the XVth World Congress of Otorhinolaryngology, Istanbul, Turkey, 23 June 1993  相似文献   
44.
We evoked both ear and eye movements in area 8b, the rostral area of frontal cortex, in two monkeys. In some sites it was possible to evoke only ear movements or only eye movements; in other locations we evoked both ear and eye movements by varying the intensity of electrical stimulation. The electrically evoked ear movements were forward, or backward, or oblique (upward-forward; upward-backward). In two penetrations the ear movements were bilateral, in the other penetrations they were contralateral. Ipsilateral ear movements were not observed. The evoked eye movements were mainly fixed-vector saccades, contralateral and with an upward orientation of about 45°. If we considered only the sites where the threshold was equal to or lower than 50 A, the stimulation of this area evoked mainly ear movements. In addition we recorded the electrical activity of 195 neurons. Of these neurons: 74% (145/195) discharged before ear movements (ear cells); 20% (40/195) discharged before ear and eye movements (ear-eye cells); 5% (10/195) discharged only before eye movements (eye cells). Ninety-one percent (132/145) of ear cells presented a preferred direction; 90% (36/40) of ear-eye cells presented a preferred direction for ear movements, and 15% (6/40) presented a preferred direction for eye movements. Eighty-five percent (34/40) of cells did not present a preferred direction for visually guided saccades and were active when the monkey made saccades toward the unlit targets (checking saccades). Our results show that a field of area 8b is related to ear movements and to eye-ear movements. The findings that it is possible to obtain both ear and eye movements with low-intensity currents and that there are cells firing for the two types of movements suggest that area 8b may be involved in the orientation and coordination of both ear and eye. This area might be considered a rostral extension of supplementary eye field (SEF) or a different region. However, based on its distinct functional characteristics and connectivity, it is probably better regarded as a separate field. Regardless, the combination of 8b and SEF may constitute a cortical center for orienting processes.  相似文献   
45.
为了解分泌性中耳炎( O M E)对内耳听觉功能的影响,对 O M E220 例、304 耳分别进行纯音测听及声阻抗测定。结果表明,部分 O M E 患者骨导听阈升高,除造成传音性耳聋外,合并感音性耳聋( S N H L)为318% ,并随着病程延长, S N H L 发病率增高。提示应积极有效地治疗本病,应用扩血管及营养神经药物可防治 S N H L的发生。  相似文献   
46.
目的:了解郑州市中学生吸烟状况。方法:采用问卷法对6所中学4123名学生进行吸烟状况调查。结果:中学生总吸烟率为4516%(1862/4123)。其中,高中组吸烟率(5049%)高于初中组(3949%),男生吸烟率(7019%)明显高于女生(315%),且中学生吸烟的严重性随年龄的增加而增加;父母的文化程度、周围人群的吸烟情况与学生吸烟率有密切关系。结论:中学生吸烟问题较重,为保护中学生的身心健康应大力开展卫生宣教。  相似文献   
47.
大鼠局灶性脑缺血模型及其与C反应蛋白变化的关系   总被引:34,自引:1,他引:33  
目的 改进大鼠大脑中动脉梗塞法,建立更接近于临床缺血性脑卒中及其再扩灌注的可靠模型,并观察其与血甭C反应蛋白变化的。方法沿大鼠右颈内动脉插入长2.1 ̄2.3cm直径0.205mm的单股尼龙丝,直达大脑中动脉起始部开口,阻断其血流,观察大鼠神经病学改变及脑组织形态学变化,并测定血清C反应蛋白含量。结果 术后大鼠表现特殊体态及典型追尾征,6h大脑中动脉供血区出现缺血性外观(TTC染色)及相应组织学变化  相似文献   
48.
目的 观察生物制剂胸腔内灌注对癌性胸水的疗效。方法 采用胸腔穿刺硅胶导管灌注高聚金葡素和白细胞介素Ⅱ生物制剂或化疗药物对照。结果 高聚金葡素组20例,有效率为82.0%,对照组丝裂霉素组20例,有效率为45%,白细胞介素Ⅱ组18例,有效率为83.3%。对照组丝裂霉素组18例,有效率为44.4%。结论经导管灌注生物制剂高聚金葡素或白细胞介素Ⅱ,其疗效明显优于胸腔内化疗。  相似文献   
49.
Otitis media is a common pediatric problem. It is well established that over half of infants and children with acute otitis media may have spontaneous recovery. Since it is difficult to predict the course (self-limited versus serious disease) all the children with acute suppurative otitis media need to be treated with antibiotics. Amoxicillin is still the initial antibiotic of choice. There are several alternate antibiotics available with activity against beta-lactamase positive bacteria. These agents have no advantage over amoxicillin in infections due to penicillin resistant pneumococci. Recent use of beta-lactam antibiotics and/or attendance in a day care where there is frequent use of antibiotics are predisposing factors for penicillin resistant pneumococcal infection. In such cases after tympanocentesis, higher dose of amoxicillin, clindamycin or intramuscular ceftriaxone should be considered. Secretory otitis media does not need to be treated with antibiotics unless the patient is in high risk group. Prophylactic use of antibiotics should be actively discouraged. Influenza and pneumococcal vaccination (2 years or older) should be encouraged in children with recurrent episodes of acute otitis media. Breast feeding should be encouraged.  相似文献   
50.

Purpose  

To assess the effect of the menstrual cycle on post-operative retching and vomiting (R& V) after middle ear surgery, and the efficacy of prophylaxis against R& V in female patients with transdermal scopolamine during either general or local anaesthesia and with intravenous ondansetron during general anaesthesia.  相似文献   
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