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101.
在新医学模式指导下预防碘缺乏病   总被引:1,自引:1,他引:0  
碘缺乏病严重危害人类健康,是最大的、可预防的智力损伤因素。通过“社会动员”,推动防治碘缺乏病(IDD)“轮子”运转,使我国消除IDD事业有了巨大进步。目前存在的问题可能会影响到该事业的可持续发展。对此,提出一些建议。  相似文献   
102.
In this paper, the auditory motion aftereffect (aMAE) was studied, using real moving sound as both the adapting and the test stimulus. The sound was generated by a loudspeaker mounted on a robot arm that was able to move quietly in three-dimensional space. A total of 7 subjects with normal hearing were tested in three experiments. The results from Experiment 1 showed a robust and reliable negative aMAE in all the subjects. After listening to a sound source moving repeatedly to the right, a stationary sound source was perceived to move to the left. The magnitude of the aMAE tended to increase with adapting velocity up to the highest velocity tested (20°/sec). The aftereffect was largest when the adapting and the test stimuli had similar spatial location and frequency content. Offsetting the locations of the adapting and the test stimuli by 20° reduced the size of the effect by about 50%. A similar decline occurred when the frequency of the adapting and the test stimuli differed by one octave. Our results suggest that the human auditory system possesses specialized mechanisms for detecting auditory motion in the spatial domain.  相似文献   
103.
小剂量吗啡对大鼠活动性的影响   总被引:4,自引:0,他引:4  
腹腔注射不同剂量吗啡,观察各组大鼠在给药后不同时间的活动性(locomotoractivity,LA),连续给药8天,每天给药后95min内,每间隔15min,记录大鼠5min内在限定空间中所走格数。结果表明:随吗啡给药剂量或次数增加,LA呈升高趋势;使大鼠LA明显兴夯的适宜低剂量为4mg/kg/day,该剂量下每天药后15-20minLA为峰值,而且此时段LA逐日升高,至第8日出现下降趋势,此毕  相似文献   
104.
有一些人出于不良的目的,宣称:患病不吃药,烧香念佛好。当然,若是邪教的目的就更险恶了!曾发生过这么一件事情:辽宁省盘锦地区,在民间传出“过年吃药不吉利”的谣言,并称,吃一次药,就一年到头药离不了口,折腾一年,一年在苦海中煎熬。这种显而易见的谣言竟还有人相信,在短短的两天时间内,一家医院就先后抢救了11位心  相似文献   
105.
Abstract

Backward walking (BW) has been extensively used in athletic training and orthopedic rehabilitation as it may have value for enhancing balance. This study identified the differences in foot intersegment kinematics (forward walking (FW) vs. time-reversed BW) and plantar pressure parameters of 16 healthy habitually shod individuals walking FW and BW using flexible shoes (SH) and under barefoot conditions (BF). BW was found to have shorter stride length (SL) and higher stride frequency (SF) under BF conditions compared with SH, which indicates a better BW gait stability under BF conditions. Decreased HX/FF dorsiflexion at HO in BW induces less plantar aponeurosis tension which may inhibit the windlass mechanism compared to FW walking. Increased forefoot relative to hindfoot (FF/HF) pronation and sequentially hindfoot relative to tibia (HF/TB) eversion combined with medially distributed plantar pressure and a higher plantar contact area in the medial side in BW–BF maybe beneficial in maintaining balance. These results indicate that BW training may be more reliable under BF conditions compared to the SH conditions based on greater sensory information feedback from the plantar area resulting in better biomechanical behavior.  相似文献   
106.
三种常用DIF检测方法的比较研究   总被引:6,自引:1,他引:5  
本研究在对DIF作出新的更为严格的界定、对三种常用的DIF检澍方法进行详细介绍的基础上.以1999年高考英语试卷75道选择题为研究材料,对三种常用的DIF检测方法进行了实证研究。结果表明:MH方法与SIBTEST方法检测的敏感性较STND方法高;MH方法与SIBTEST方法检出的一致性很高;SIBTEST方法具有较好的性能,在实际应用中可以作为首选的方法;在进行DIF检测时,样本容量在1000左右为宜。  相似文献   
107.
The effectiveness of tetraethylammonium (TEA) and high-frequency stimulation (HFS) in inducing long-term synaptic modification is compared in CA1 and dentate gyrus (DG) in vitro. High-frequency stimulation induces long-term potentiation (LTP) at synapses of both perforant path-DG granule cell and Schaffer collateral-CA1 pyramidal cell pathways. By contrast, TEA (25 mM) induces long-term depression in DG while inducing LTP in CA1. The mechanisms underlying the differential effect of TEA in CA1 and DG were investigated. It was observed that T-type voltage-dependent calcium channel (VDCC) blocker, Ni2+ (50 μM), partially blocked TEA-induced LTP in CA1. A complete blockade of the TEA-induced LTP occurred when Ni2+ was applied together with the NMDA receptor antagonist, D-APV. The L-type VDCC blocker, nifidipine (20 μM), had no effect on CA1 TEA-induced LTP. In DG of the same slice, TEA actually induced long-term depression (LTD) instead of LTP, an effect that was blocked by D-APV. Neither T-type nor L-type VDCC blockade could prevent this LTD. When the calcium concentration in the perfusion medium was increased, TEA induced a weak LTP in DG that was blocked by Ni2+. During exposure to TEA, the magnitude of field EPSPs was increased in both CA1 and DG, but the increase was substantially greater in CA1. Tetraethylammonium application also was associated with a large, late EPSP component in CA1 that persisted even after severing the connections between CA3 and CA1. All of the TEA effects in CA1, however, were dramatically reduced by Ni2+. The results of this study indicate that TEA indirectly acts via both T-type VDCCs and NMDA receptors in CA1 and, as a consequence, induces LTP. By contrast, TEA indirectly acts via only NMDA receptors in DG and results in LTD. The results raise the possibility of a major synaptic difference in the density and/or distribution of T-type VDCCs and NMDA receptors in CA1 and DG of the rat hippocampus.  相似文献   
108.
Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) are well recognized syndromes related to the rapid correction of hyponatremia, which are reported to show brain stem signs and various movement disorders. Cognitive dysfunction and neuropsychological findings, however, have seldom been reported. Cognitive manifestations in osmotic myelinolysis may have been underestimated due to the prominent brain stem symptoms and movement disorders. We report a case of EPM without CPM and describe the neuropsychological findings of EPM. The absence of CPM in this case made it possible to test neuropsychological function in the acute stage. Neuropsychological testing showed severe impairment of attention, verbal and visual memory, visuospatial function, and frontal/executive function. Language and language-related functions were normal except naming.  相似文献   
109.
结直肠癌诊断模式的若干思考   总被引:1,自引:1,他引:0  
结直肠癌是常见的消化道恶性肿瘤,然而在临床上得到诊断时大多已经到了中晚期,错过了最佳的治疗时机。近年来,随着基因相关技术及生物信息技术的迅猛发展,结直肠癌诊断方法得到不断改进,但早期诊断仍不尽如人意。因此现有的诊断模式值得我们去深思,从哲学意义上探索更为完善的诊断模式。  相似文献   
110.
十五年来中国男性择偶标准的变化   总被引:4,自引:0,他引:4  
对《中国妇女》1985年至2000年15年间每隔5年选择一年,并在每一季度中选择一期杂志,统计男性刊登的征婚启事,总共得到332例。采用统计学方法进行定量研究。发现中国男性在15年间对自身的人品、财产、相貌的重视程度显著增高,对自身的婚史和事业的重视程度明显降低;对女方的持家能力的重视程度显著增高,对女方的健康和工作的重视程度显著降低。当代中国男性的择偶标准随时间的推移有了明显的变化,但仍受到中国传统观念的影响。  相似文献   
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