虚拟现实视觉训练对集合不足长期疗效的观察

目的 探究基于虚拟现实(VR)的视觉训练对集合不足受试者视功能与主观问卷的影响以及长期疗效的观察。 方法 研究共纳入集合不足受试者36例,将受试者随机分入基于虚拟现实的视觉训练组(VR组)及传统训练组(OBVAT组)。训练时长为每周1 h,共12周。在训练前、训练第6周、训练第12周及训练结束后6个月完成双眼视功能参数及主观问卷调查(CISS)。 结果 重复测量方差分析结果显示,集合不足的受试者(包括VR组与OBVAT组)进行视觉训练12周后,CISS得分降低、集合近点减小、正融像性聚散范围值增加,视近外隐斜减小(P<0.001)。VR组与OBVAT组集合不足的受试者在训练结束后6个月的视功能参数与训练12周相比无统计学差异(P>0.05)。VR组与OBVAT组之间各项参数的组间差异无统计学意义(P>0.05)。 结论 研究结果显示基于虚拟现实的视觉训练可以显著改善集合不足受试者的主观症状与视功能参数,与传统训练方法相比无统计学差异;在训练结束后6个月,仍可维持一定效果。     

Evidence for frequent divergence impairment in French dyslexic children: deficit of convergence relaxation or of divergence per se?

Aim There is a controversy as to whether dyslexic children present visuo-motor disabilities such as vergence and accommodative problems assessed with orthoptic tests. The purpose of this study is to re-examine this issue in a large population of children. Methods Extensive orthoptic evaluation was made in 57 dyslexic and 46 non-dyslexic (“normal”) age-matched children. Convergence and divergence capacities were evaluated at two distances (30 cm and 400 cm). Results Binocular vision measured with stereo-acuity tests was normal in dyslexics. In contrast, the near point of convergence was significantly more remote in dyslexics; most importantly, divergence at both far and near distance was significantly more reduced in dyslexics (median value 4 pD and 10 pD, respectively, at far and near) than in “normals” (median value 6 pD and 12 pD, at far and near). Conclusion The existence of the divergence deficit at far distance indicates the presence of deficit of divergence per se, independently from convergence and accommodation relaxation. This result is novel and corroborated by physiological studies indicating distinct control of convergence and divergence, both at the cortical and subcortical premotor level. We conclude that vergence deficits are frequently present in dyslexics, and that dyslexics should be re-educated; training should address distinctively convergence and divergence subsystems.     

集合不足型外斜视外直肌斜向后徙

目的　评价集合不足型外斜视外直肌斜向后徙的效果。方法　研究组 2 2例 ,对照组 8例 ,看近斜视角大于看远斜视角至少 15PD ,研究组 2 2例行外直肌斜向后徙术 ,对照组 8例行标准的外直肌后徙术。结果　研究组 18/2 2术后看近外斜度≤ 10PD ,2 2 /2 2术后看远外斜度≤ 10PD ,看近看远外斜角平均差值由术前 2 5± 8 11PD减少到术后 5 2 3± 4 0 3PD。对照组仅 3 /8术后看近外斜度≤10PD ,6/8术后看远外斜度≤ 10PD。结论　集合不足型外斜视外直肌斜向后徙术效果优于标准的外直肌后徙术。     

后牙颊舌向聚合度的测量及比较研究

目的：测量60副正常He牙列模型，获取后牙牙体颊舌向聚合度的正常值，并进行比较研究。方法：选取60副正常He牙列模型，以寒天印模材取模，超硬石膏灌注，对模型各牙位牙齿进行定点，转移模型各定点至坐标纸，测量，计算颊舌向聚合度，并比较它们之间的异同。结果：1）得出后牙各牙位牙体颊舌向聚合度。2）上下同名牙相同方向聚合度均数经方差分析，有非常显著性差异。结论：上下同名牙聚合度之间差异均较大。     

秦皇岛市海港区世行贷款结核病控制项目终期评价

目的 :评价世界银行贷款结核病控制项目成效。方法 :根据海港区 1994～ 2 0 0 1年结核病登记报表分析结核病人登记和治疗效果。结果 :政府累计投入配套经费 170 3 10 .62元 ,项目期间累计治疗涂阳病人 5 99例 ,治愈率由项目前的 72 %提高到 95 .66% ,与项目前相比为国家节约治疗费用 72 .19万元。结论 :实施世行贷款结核病控制项目效果显著 ,推动了海港区肺结核病预防和控制工作的发展     

Conditions for convergence of Monte Carlo EM sequences with an application to product diffusion modeling

Intractable maximum likelihood problems can sometimes be finessed with aMonte Carlo implementation of the EM algorithm. However, there appears to be little theory governing when Monte Carlo EM (MCEM) sequences converge. Consequently, in some applications, convergence is assumed rather than proved. Motivated by this problem in the context of modeling market penetration of new products and services over time, we develop (i) high-level conditions for rates of almost-sure convergence and convergence in distribution of any MCEM sequence and (ii) primitive conditions for almost-sure monotonicity and almost-sure convergence of an MCEM sequence when Monte Carlo integration is carried out using independent Gibbs runs. We verify the main primitive conditions for the Bass product diffusion model and apply the methodology to data on wireless telecommunication services.     

集合不足视觉训练回顾性分析研究

目的 回顾性分析集合不足患者的症状和体征情况以及治疗的效果评价.方法 采用回顾性分析的方法,收集2010年10月到2011年2月天津市眼科医院视光中心接诊的集合不足患者33例,其中男性18例,女性15例,年龄8～33岁,平均(14.12±5.77)岁.所有患者眼科检查均排除眼科疾病,矫正视力≥1.0.所有患者进行视疲劳主观问卷调查、双眼视功能检查和散瞳验光,确诊为集合不足,并进行视觉训练.采用描述性研究及配对t检验进行统计学分析.结果 集合不足患者屈光度范围为-6.88～+0.50D,均数为(-2.87±2.13)D,其中高度近视5例(15.2％),中度近视例11(33.3％),轻度近视13例(39.4％),4例(12.1％)为正视.症状问卷得分≧16分者为20例(60.6％),平均得分为(21.13±10.81).远处隐斜位平均值为外隐斜-4Δ,近处外隐为-11.7Δ,远近隐斜差值为7.7Δ.10例(30.3％)患者无立体视,23例(69.7％)有立体视.计算性AC/A平均值为2.85Δ/D.15例(45.5％)患者正相对调节(PRA)≦1.50 D,11例(33.3％)患者负相对调节≦1.50 D.所有患者进行视觉训练,训练后有2例患者失访.23例(74.2％)患者在训练后3个月内症状明显缓解,问卷得分均＜16.比较视觉训练前后的体征变化发现,患者眼位能控制在正常范围,看远跟位为外隐斜-1.7Δ,看近眼位为外隐斜-3.48Δ,远近差值明显减小,为1.59Δ,差异有统计学意义(t=-3.708、P=0.001,t=-8.154、P=0.000,t=-6.868、P=0.000).无立体视的患者中有5例(50％)恢复了立体视.AC/A(t=-7.821,P=0.000)、正相对调节(t=5.639,P=0.000)、负相对调节(t=-2.449,P=0.020)明显改善.结论 集合不足患者屈光度范围集中在轻中度近视.视觉训练后患者控制眼位能力明显提高,特别是近处外隐斜减少,半数无立体视患者恢复了立体视.同时调节功能也得到改善,集合不足症状明显减轻.     

由相对集合域求近用镜光心

在眼的相对集合域图中添加一条ＡＣ／Ａ线，提出以ＡＣ／Ａ线确定集合的舒适区，根据Ｄ线是否落在舒适区内来确定各种类型近用镜光心的位置。     

Convergence of afferent inputs from the chorda tympani, lingual-tonsillar and pharyngeal branches of the glossopharyngeal nerve, and superior laryngeal nerve on the neurons in the insular cortex in rats

The responses of single neurons in the insular cortex to electrical stimulation of the chorda tympani (CT), lingual-tonsillar branch of the glossopharyngeal (LT-IXth) nerve, pharyngeal branch of the glossopharyngeal (PH-IXth) nerve, and superior laryngeal (SL) nerve were recorded in anaesthetized and paralyzed rats. Ninety-four neurons responding to stimulation of at least one of the four nerves were identified from the insular cortex. Most of the neurons were located in the posterior portion of the insular cortex; the mean location was 0.8 mm anterior to the anterior edge of the joining of the anterior commissure (AC) and was 1.4 mm dorsal to the rhinal fissure (RF). Of the 94 neurons, 84 (89%) received convergent inputs from two or more nerves, and the remaining 10 (11%) received inputs from one nerve. The neurons responding to the CT stimulation were distributed more anteriorly than those responding to other three nerves in the anterior-posterior dimension. Our results indicate that the neurons recorded mainly from the posterior portion of the insular cortex receive convergent inputs from the oropharyngolaryngeal regions.