近视眼角膜后表面曲率分布特点及其影响因素

 目的 探讨近视患者角膜后表面曲率的分布特点及其影响因素.方法 选取青年近视200例(400眼),按屈光度不同分为4组,应用OrbscanⅡ眼前节分析系统对患者的角膜中央点、最薄点、后表面平均屈光度最大点,以及距角膜中心1.5 mm ,2.5 mm上方、下方、颞上、颞下、鼻上、鼻下、颞侧、鼻侧部位的后表面曲率及相对应的后表面高度、前表面曲率、角膜厚度、前房的深度进行测量.结果 后表面最大曲率值(-6.74±0.36) D,负值最大点多位于旁中心1.5 mm上方(30.6%),其次是旁中心1.5 mm下方(19%).后表面平均屈光度最大点、最薄点、中央点3个点的后表面曲率在不同近视组中差异无统计学意义.不同部位的后表面曲率与影响因素相关分析结果:后表面平均屈光度最大点:后表面曲率与后表面高度,前表面曲率呈负相关.与相应的角膜厚度呈正相关.最薄点:后表面曲率与后表面高度和前表面曲率呈负相关.与角膜厚度呈正相关.中央点:后表面曲率与后表面高度,前表面曲率呈负相关.结论 角膜后表面曲率负值最大点多位于旁中心1.5 mm上方,其次是旁中心1.5 mm下方.角膜后表面平均屈光度最大点、最薄点、中央点3个点的后表面曲率与近视程度无关;影响角膜后表面曲率的因素包括后表面高度、角膜厚度和前表面曲率.     

Orbscan角膜地形图检查的护理配合

Orbscan角膜地形图系统是一利用光学扫描装置对被检查角膜进行扫描，从而获取角膜前、后高度地形图，角膜前表面屈光力地形图及全角膜厚度图，其角膜厚度由颜色编码得出彩色图形，暖色表示角膜薄，而冷色则表示角膜较厚。此项检查安全、无创伤，可重复性强，广泛运用于屈光手术的设计、圆锥角膜诊断和治疗评判、散光分析、白内障人工晶体植入术等，对提高治疗效果具有举足轻重的作用。我科于2004年6月至今使用博士伦Orbscan Ⅱz角膜地形图检查588例，现将护理体会报告如下。     

AstraMax角膜地形图在圆锥角膜早期诊断中的作用

目的 评价AstraMax角膜地形图在圆锥角膜早期诊断中的重要作用。方法 对2002年10月～2004年6月来我院准分子激光治疗中心欲进行准分子屈光性角膜切削术或准分子激光原位角膜磨镶术的2202例术前患者4382只眼行角膜地形图检查,以筛选亚临床期圆锥角膜及可疑圆锥角膜。结果 共筛选出2人4眼亚临床期圆锥角膜(占0．09％),可疑圆锥角膜5人8眼。结论 AstraMax角膜地形图在圆锥角膜的早期诊断中具有简便、快速、准确的优点,是准分子激光术前筛查的重要工具。     

Pentacam系统测量准分子激光角膜屈光手术前近视患者角膜厚度的临床观察

目的比较Pentacam系统与A型超声角膜测厚仪测量准分子激光手术前近视患者中央角膜最薄点厚度的差异。方法对准备行准分子激光角膜屈光手术的近视患者69例138只眼,分别采用Pentacam系统和A型超声角膜测厚仪测量角膜中央最薄点厚度,对测量结果进行统计学分析。结果 Pentacam系统、A型超声角膜测厚仪测量中央角膜最薄点厚度值分别为（548.0±28.9）μm和（538.8±29.4）μm,两者高度正相关（P〈0.05）。Pentacam系统比A型超声测得的中央角膜厚度厚（9.2±9.9）μm,差异有显著意义（P〈0.05）,该差值与A型超声测量角膜厚度值负相关（P〈0.05）,而与屈光度、年龄等无关。结论 Pentacam测量近视患者角膜厚度值略高于A型超声法,尽管二者有较好的一致性,但相互间还不能完全替代。     

准分子激光屈光性角膜切削术对角膜散光的影响

为研究准分子激光角膜切削术（ＰＲＫ）能否引起角膜散光，用大光斑多区切削的进口准分子激光机治疗无散光高度近视７２眼和中、低度近视８１眼。经角膜地形图分析，高度和中、低度近视眼切削前后不规则散光指数无明显变化，说明ＰＲＫ不是增加角膜不规则散光的因素。术后１年，高度近视眼角膜中央３ｍｍ散光比术前增高，有显著性差异。可能与多区、大光斑多次切削时，每次切削中心不能完全重叠等因素有关。     

准分子激光双面式切削原位角膜磨镶术治疗近视的临床研究

准分子激光原位角膜磨镶术（LASIK）因其术后视力恢复快、屈光状态稳定、矫正范围大、术后疼痛小等优点成为目前临床上应用最广泛的矫正屈光不正的手术方式。但是对于近视度数较高而角膜相对偏薄的患者，LASIK术后有可能出现医源性圆锥角膜，这种并发症表现为进行性的角膜中央膨出。可能的诱发因素有患者的年龄、术前眼内压、角膜厚度、切削深度、切削区直径的大小、矫正的屈光度及手术保留的瓣下角膜厚度等，     

薄角膜的近视散光眼行准分子激光原位角膜磨镶术后角膜生物力学状态长期观察

目的探讨薄角膜(500μm)近视散光眼行准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后长期(≥60个月)的角膜生物力学状态、手术的安全性、有效性及准确性。方法选取1998年9月至2010年9月,行LASIK手术且资料完整的薄角膜患者89例175只眼,观察术前及术后末次的裸眼视力(uncorrected visual acuity,UCVA)、矫正视力(corrected distance visual acuity,CDVA)、球镜度数、散光度数、等效球镜度数(spherical equivalent,SE),以及术前的中央角膜厚度(central corneal thickness,CCT)及术后末次复查时的CCT、角膜瓣厚度与剩余基质床厚度(residual stromal bed thickness,RSBT)及角膜地形图。计算安全指数、有效指数、准确性以及角膜瓣厚度+切削深度)/术前中央角膜厚度(Percent Tissue Altered,PTA)与剩余基质床厚度/术前中央角膜厚度(Percentage stromal bed thickness,PSBT)结果安全指数为1.09,有效指数为0.99,末次复查的SE在±0.50D、±1.00D范围之内的百分比分别为71.2%、87.7%,PTA为20%~55%(40%±6%),PSBT为51%~85%(61%±9%),无术眼发生继发性圆锥角膜。结论 PSBT达到50%及以上时,薄角膜(459~499μm)近视散光眼行LASIK术后角膜生物力学状态长期稳定,且安全有效。     

Orbscan Ⅱ系统与A超角膜测厚仪测量近视眼角膜中央厚度的比较

 目的 将Orbscan Ⅱ系统与A超角膜测厚仪测量的近视眼中央角膜厚度的结果,进行对比分析,为临床手术提供准确的数据.方法 选取近视患者200例(400只眼),按屈光度、A超测得角膜厚度不同分成4组.分别应用OrbscanⅡ系统及A超角膜测厚仪对角膜中央厚度进行测量.结果 OrbscanⅡ系统与A超角膜测厚仪测得角膜中央厚度分别为(568.06±34.29) μm和(536.25±33.90)μm,两者测量结果存在差异(P＜0.01).OrbscanⅡ系统测量结果较A超角膜测厚仪结果厚(31.81±16.39) μm.按屈光度不同分组,即低度数组-0.50～-3.00 D,中度数组-3.25～-6.00 D,高度数组-6.25～-9.00 D,超高度数组-9.25～-15.00 D,Orbscan Ⅱ系统与A超角膜测厚仪两者之间差异显著(P＜0.01).按A超测得角膜厚度分为4组,即Ⅰ组≤500 μm,Ⅱ组500～536 μm,Ⅲ组536～572 μm,Ⅳ组≥572 μm.Orbscan Ⅱ系统与A超角膜测厚仪两者之间差异显著(P＜0.01).结论 Orbscan Ⅱ系统中央角膜厚度测量值比A超角膜测厚仪测量值厚约30 μm,Orbscan Ⅱ系统不能完全替代A超角膜测厚仪.     

角膜胶原交联治疗圆锥角膜的初步临床观察

目的观察角膜胶原交联治疗进行性圆锥角膜的早期临床表现。方法10只眼的进行性圆锥角膜接受角膜胶原交联治疗,主要观察术中和术后第1、3、5天术眼反应,以及术后1、3个月视力、角膜情况、眼压、角膜地形图等情况。结果去除角膜上皮后,维生素B2可渗入角膜基质层,紫外线照射下呈黄绿色荧光,治疗后数小时消退。第3天时角膜上皮愈合,角膜轻度水肿。术后1个月在裂隙灯显微镜下可见轻度角膜基质层混浊,可持续至治疗后3个月。3只眼的角膜地形图平均屈光度数较治疗前增加约0．5D。1只角膜水肿比较重的眼,角膜厚度较治疗前略有增加。结论角膜水肿和角膜轻度混浊现象存在于大多数治疗眼的早期观察中,提示该治疗早期,除了去除角膜上皮继发的组织反应外,可能还有光化学治疗本身对角膜的作用。     

准分子激光单区和多区切削治疗中度近视的疗效比较

为探讨单区和多区准分子激光角膜切削对中低度近视的治疗作用和对角膜愈合的影响，３４例双眼－３．００Ｄ～－５．７５Ｄ患者分别行单区和多区准分子激光切削治疗，角膜地形图评价其疗效，结果表明中度近视多区切削术后角膜表面形态恢复快，但视力恢复早期两种治疗无显著性差异     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

Oxygen uptake and ventilation during rowing and running in females and males

This study evaluated if the ventilatory response to exercise is impaired by the cramp position of rowing. Maximal oxygen uptake (VO2max), maximal expiratory volume (VEmax), and maximal heart rate (HRmax) during rowing and running were compared in 55 males (age, mean +/- SD, 21 +/- 3 years; height 176 +/- 5 cm; body mass 72 +/- 6 kg) and 18 females (age 20 +/- 2 years; height 164 +/- 5 cm; body mass 61 +/- 4 kg). VEmax was larger during rowing than during running (males, 157 +/- 16 vs. 147 +/- 13 L min(-1); 114 +/- 9 vs. 105 +/- 11 L min(-1), P<0.01). Also VO2max was larger during rowing than during running (males, 4.5 +/- 0.5 vs. 4.3 +/- 0.4 L min(-1); females, 3.3 +/- 0.4 vs. 3.2 +/- 0.4 L min(-1), P<0.01). However, HRmax was lower during rowing than during running (males, 194 +/- 8 vs. 198 +/- 11 beats min(-1); females, 192 +/- 6 vs. 196 +/- 8 beats min(-1), P<0.05). VEmax was correlated to body mass and fat-free mass, as was VO2max. Thus, the oxygen pulse (VO2max/HRmax) was larger during rowing than during running, while the ventilatory equivalent for oxygen (VEmax/VO2max) was similar. We showed that bending the body during rowing does not seem to impair ventilation either in males or in females. The results indicate that VEmax and VO2max relate to body size and fat-free mass for both females and males. The findings indicate that the involvement of more muscles, the entrainment, and the body position during rowing facilitates ventilation and venous return and lowers maximal heart rate.     

幽门螺杆菌分泌与重组表达的VacA蛋白的分离纯化及其致细胞空泡效应与凋亡的对比研究

目的：分离纯化幽门螺杆菌分泌和重组表达的细胞空泡毒素抗原（ VacA）蛋白,并评价其致细胞空泡效应及致细胞凋亡效应。方法分别从幽门螺杆菌ATCC26695菌株培养上清和重组表达VacA蛋白的pQE30-VacA-E．coliM15基因工程菌中分离纯化VacA蛋白,经酸化后,以不同终浓度（5,10 ng／ml）分别与人胃腺癌AGS细胞共孵24 h,观察致空泡效应,并通过流式细胞术检测细胞凋亡。结果成功分离纯化出幽门螺杆菌分泌和重组表达的VacA蛋白;幽门螺杆菌分泌的VacA蛋白能显著引起AGS细胞的空泡样改变及凋亡（P＜0．01）,而重组表达的VacA蛋白致细胞空泡样改变及凋亡不显著（ P＞0．05）。结论幽门螺杆菌分泌的VacA蛋白有良好的空泡毒性及致凋亡效应,而重组表达的VacA蛋白无致空泡及凋亡效应,幽门螺杆菌分泌的VacA蛋白可用于VacA作用机制的研究。     

化学和生物学融合对国际武器公约履约的影响

化学武器公约（ CWC）和生物武器公约（ BWC）是为禁止生产、发展、储存和使用化学武器和生物武器而制定的国际公约。近年来,科学技术快速发展,知识交叉渗透,学科之间出现整合和融合,促进了科技进步和经济发展。其中化学和生物学融合在有力促进制药、健康卫生、绿色化学和环境保护等产业进步的同时,也对化学和生物武器公约的履约产生了重要的影响。该文综述了与化学武器和生物武器公约相关的化学和生物学融合进展,并分析其对公约履约的影响。     

Old and dangerous: Prison and dementia

Older prisoners are the fastest growing group of prisoners in many countries. The purpose of this study is to explore the phenomenon of detention of persons suffering from dementia. Medline searches were conducted for relevant articles, chapters and books published until August 2016. Search terms included dementia, elderly, prison and criminal. Publications found through this indexed search were reviewed for further relevant references. As results, there is a lack of data about elderly with dementia in prisons. Given the rise in the average age, it is reasonable to hypothesize that the number of older prisoners is growing. Moreover, some elderly are imprisoned with a concomitant cognitive impairment or psychiatric disorder while others will develop such diseases once incarcerated. At the present time, legal and social systems seem unprepared to handle the phenomenon of dementia in prison. As proposal, health assessments for older first time offenders should become a practice inside the correctional facilities and include an evaluation for specific health issues, such as psychiatric comorbidity and cognitive impairment.     

Kidney and iodinated and gadolinium-based contrast agents

In patients with renal failure, iodinated contrast agents may cause acute deterioration of the renal function and gadolinium-based contrast agents (GBCAs) may cause nephrogenic systemic fibrosis (NSF). The administration of a contrast agent must thus be reviewed for each patient and evaluation of renal function is paramount even though its estimation using formulas derived from the creatinine level may fluctuate. For iodinated contrast agents, contrast induced nephropathy is reduced by hydratation, preferably intravenous, when the GFR is less than 60 ml/min. The risk for intravenous injections is less than the risk for arterial injections, and the GFR threshold may be reduced to 45 ml/min. For gadolinium-based contrast agents, patients at risk for NSF are those with end-stage renal disease and patients undergoing dialysis. In such cases, the injection of a gadolinium-based contrast agent is only considered after a risk-benefit analysis has been completed, an alternate linear or macrocyclic agent issued and the dose limited to 0,1 mmol Gd/kg. Recently, recommendations from US and European agencies have converged. Learning objectives: to be familiar with the risk factors of CIN with iodinated contrast agents; to be familiar with hydration procedures for patients at risk of CIN; to be familiar with the diagnostic criteria of NSF; to be familiar with the classification of GBCA with regards to the risk of NSF; to be familiar with the contraindications of the different groups of GBCA.     

Coracoclavicular and coracoacromial ligament calcification and ossification

Thirty-six patients with calcification or ossification at or around the coracoclavicular and coracoacromial regions were analyzed with regard to type, location, and configuration of the deposits and related clinical history. Calcification or ossification in the coracoclavicular region resulted largely from trauma (36%) or renal failure (28%). Trauma patients may develop punctate calcification or ossification but do not develop the tumoral type of calcification. About 5% of the renal failure patients had coracoclavicular ligament calcifications, one-half of which were of the tumoral type. Renal failure patients may have punctate or tumoral calcifications but do not develop ossification.     

Cross-sectional and longitudinal comparisons of self-reported and device-assessed physical activity and sedentary behaviour

ObjectivesTo examine the longitudinal associations and differences between self-reported and device-assessed physical activity (PA) and sedentary behaviour (SB), using a multifaceted statistical approach.DesignLongitudinal measurement burst.MethodsIn total, 52 university students (78% female) aged 18–38 years (mean = 21.94 ± 4.57 years) participated. The study consisted of three blocks of six days of measurement, during which participants wore an accelerometer on their wrist for the entire block, and self-reported their PA over the 6 days at the end of each block.ResultsMeaningful latent differences between methods were observed for moderate PA and SB across all three assessment periods, such that participants underreported the time spent in each activity. Bland–Altman plots revealed a positive mean difference for vigorous PA, with over-reporting increasing as mean levels increased. Negative mean differences were observed for all other intensities. Underreporting of moderate PA increased as the mean level increased, whereas for light PA and SB, underreporting decreased at high levels. Repeated measures correlations revealed a meaningful association for vigorous PA only, suggesting that as self-reported minutes increase so too do device-measured minutes.ConclusionsWe found evidence of cross-sectional and longitudinal differences and weak associations between self-reported and device-assessed PA and SB. Future work is needed to enhance the quality of self-reported methods to assess PA and SB (e.g., face and content validity), and consider improvements to the processing of device-based data.