动态CT扫描对小肝癌诊断的意义

用动态ＣＴ扫描确诊小肝癌１７例，表明动态ＣＴ扫描对小肝癌具有很高的诊断价值。     

肝癌与肝硬化腹水微量元素Cu、Zn测定的临床诊断价值

腹水是一种病理性腹腔渗出液或漏出波．肝癌、肝硬化晚期，腹膜炎等多种疾病可致病人出现腹水，由于引起腹水病因不同，腹水中各物质含量亦有所不同．关于腹水中微量元素含量的研究尚少见报道。为此作者分三组测定了４８份腹水中的Ｃｕ、Ｚｎ含量，进行了分析比较，结果如下：１．Ｃｕ含量．其它组高于肝癌组，肝癌组高于肝硬化组，各组间差异非常显著，Ｐ＜０．０１。２．Ｚｎ含量，肝癌组高于肝硬化组，肝硬化组高于其它组，各组间差异显著，Ｐ＜０．０５．３．以上结果说明，测定腹水中Ｃｕ、Ｚｎ含量是一项了解腹水性质较敏感指标，尤其是肝硬化癌变时，Ｃｕ、Ｚｎ含量有明显的变化．     

超声弹性成像联合超声造影在鉴别原发性及转移性肝癌中的应用

为探讨超声弹性成像联合超声造影在鉴别原发性及转移性肝癌中的应用价值，选择2016年12月至2018年12月期间本院消化外科住院部收治的肝癌患者160例作为研究对象，根据病理组织学检查结果将患者分为原发组和转移组，各80例，两组进行超声弹性成像和超声造影检查，分析单项和两者联合检查对原发性及转移性肝癌的鉴别诊断效能。结果显示，原发组超声弹性成像评分（3.41±0.85）分，明显高于转移组的（1.52±0.62）分，两组比较差异具有统计学意义，P<0.05。与转移组相比较，原发组造影峰值时间明显延长，造影始增时间明显缩短，造影峰值增强速率明显降低，两组比较差异具有统计学意义（P<0.05）。两者联合检查对原发性及转移性肝癌的鉴别诊断灵敏度、特异度、阳性预测值、阴性预测值、准确度高于超声弹性成像或超声造影单项检查，漏诊率和误诊率低于超声弹性成像或超声造影单项检查，两者联合检查对原发性及转移性肝癌的鉴别诊断准确度明显高于超声造影单项检查，P<0.05。说明超声弹性成像联合超声造影有利于明显提高原发性及转移性肝癌的鉴别诊断准确度，值得临床推广应用。     

16例原发性肝癌患者血清锌测定及分析

通过１６例原发性肝癌患者血清锌测定，结果发现：患者血清锌明显低于对照组。提示低血糖锌与原发性肝癌有关。对其关系进行了初步探讨。     

硒对不同水体致癌因子诱发健康人微核的拮抗作用

采用微核检测技术，研究了亚硒酸钠对启东肝癌高发区不同类型饮用水诱发健康人外周血淋巴细胞微核的拮抗作用。结果表明：（１）各实验水体对细胞的毒性作用，宅沟水〉泯沟水〉自来水〉双蒸水。微核率随着实验水体剂量的增加而升高；（２）１ｍｇ／Ｌ的亚硒酸钠浓度对泯沟水，自来水诱发的微核效应有是显的抑制和／或拮抗作用，呈现明显的剂量－效应关系，提示肝癌高发区饮用水体中确存在与肝癌发病相关的致畸因子，补硒确有防与治原     

Ge—132对小鼠H22肝癌移植瘤的影响

Ｇｅ－１３２对小鼠Ｈ２２肝癌移植瘤的实验研究证明：１．Ｇｅ－１３２对Ｈ２２肝癌移植瘤有一定的抑制作用，３００ｍｇ／ｋｇ体重剂量抑瘤率达到３６．１９％；２．增强机体的抗氧化作用，抑制脂质的过氧化物水平；３．促进免疫功能，当Ｇｅ－１３２和环磷酰胺联合使用时，可抵抗环磷酰胺的免疫抑制作用，而且并不减弱其抑制瘤作用。     

铜锌含量对肿瘤的诊断价值

探讨了血清、头发中Cu、Zn及Cu／Zn比值对肺癌、肝癌及胃肠道肿瘤的诊断价值，检测了171例样品，并与156名健康者进行对比研究．结果显示血清和头发Cu、Cu／Zn可作为恶性肿瘤的筛选指标，发Cu、Cu／Zn有助于肺癌临床分期，血清Cu有助于肝癌诊断和预示进展程度，而Cu／Zn可能对胃肠道肿瘤的诊断和预后更有用．     

硒酸脂多糖治疗原发性肝癌临床疗效观察

硒酸脂多糖具有硒和多糖两者特殊作用，它治疗原发性肝癌有肯定的疗效。     

人原发性肝癌中的转甲状腺素蛋白(Transthyretin)基因

本文从人正常肝对原发性肝癌的递减式cDNA文库(Subtracting cDNA libra-ry)中筛选出pG8cDNA克隆.Northem杂交证明它在正常肝中高度转录,而在9例肝癌中转录严重受阻遏.9例肝癌DNA MspI酶切杂交信号提示,4例肝癌中该基因存在部分DNA片段的丢失.在另7对肝癌及癌旁组织样本中,有4例肝癌中该基因同样存在部分片段丢失.cDNA序列分析证明它与转甲状腺素蛋白(Transthyretin,TTR)基因的编码区全部同源.本文首次报道了在人肝癌中TTR基因转录严重受阻遏及在基因结构上可能存在丢失或缺陷,提示TTR基因可能是人肝癌中基因缺陷的一个标记或抗癌基因之一.     

斑蝥素衍生物的合成、抗肝癌活性及构效关系研究

斑蝥素衍生物具有结构多样性和良好的抗肝癌活性。本文以呋喃、顺丁烯二酸酐为原料,合成了35个斑蝥素衍生物。以顺铂为阳性对照药,经MTT法测试了所合成化合物对人肝癌HepG2细胞的体外抗肿瘤活性。结果表明,化合物6d、6f、6g、6h、6i的抗肝癌活性与顺铂相当,其中,斑蝥素酰亚胺类化合物具有较好的抗肝癌活性,且当取代基为吸电子基或含氮杂环时化合物显现出较强的抗肝癌活性,该类化合物具有潜在的抗肝癌应用价值。     

Measurements of the UVR protection provided by hats used at school

The importance of protection against solar ultraviolet radiation (UVR) in childhood has lead to SunSmart policies at Australian schools, in particular primary schools, where children are encouraged and in many cases required to wear hats at school. Hat styles change regularly and the UVR protection provided by some of the hat types currently used and recommended for sun protection by the various Australian state cancer councils had not been previously evaluated. The UVR protection of the hats was measured using UVR sensitive polysulphone film badges attached to different facial sites on rotating headforms. The sun protection type hats included in this study were broad-brimmed hats, "bucket hats" and legionnaires hats. Baseball caps, which are very popular, were also included. The broad-brimmed hats and bucket hats provided the most UVR protection for the six different sites about the face and head. Legionnaires hats also provided satisfactory UVR protection, but the caps did not provide UVR protection to many of the facial sites. The highest measured UVR protection factors for facial sites other than the forehead were 8 to 10, indicating that, while some hats can be effective, they need to be used in combination with other forms of UVR protection.     

Cathodic protection of ships in brackish water

The operation of ice-going vessels depends on the condition of the hull surface. Corrosion increases the roughness of ship hull, which increases drag and fuel consumption. The hull surface smoothness is maintained by using coatings and cathodic protection. The cold brackish water is different from ocean water as it has lower salt content, lower conductivity, and higher concentration of dissolved oxygen. These factors mean that the design of the cathodic protection system for ship hulls requires different design values, such as protection current density and protected length, than those given in cathodic protection standards. In this paper, we have estimated the protection current density with polarization curves and the protected length by using Wagner number and dimension and conductivity scaling. In brackish water the protection current density was two times that in ocean water. The protected length in brackish water varied between 10 and 15% of that in ocean water. In poorly conducting brackish water, the current capacity of a cathodic protection system is used mostly for overcoming the solution resistance, not for delivering protection current.     

无机化学在文物修复和保护中的应用

本文探讨了无机化学在文物修复和保护研究中的应用。介绍了文物保护研究的无机化学原理和方法,并从文物清洗、修复和保护等方面进行了论述。     

Sun-protective Properties of Technical Sportswear Fabrics 100% Polyester: The Influence of Moisture and Sweat on Protection against Different Biological Effects of Ultraviolet (UV) Radiation

The use of technical sportswear is now widespread, but the degree of protection these fabrics offer against UV radiation is not known. We have analyzed the capacity of different types of technical sportswear fabrics to protect against different UV biological effects. A sample of 34 100% polyester t-shirts from different manufactures was classified by color, fabric structure, cover factor, and due to different tonalities, dark, and clear color. Ultraviolet protection factor was calculated according to UNE-EN13758. The protection factor for other biological effects as pre-vitamin D₃ production, non-melanoma skin cancer, photoimmunosuppression, and photoaging was analyzed. The effects of moisture and sweat in protection were also evaluated. From the analyzed sample garments, more than 75% achieved an excellent protection value (protection factor 40–50+). Higher values were found in double-layer type (P < 0.05). Cover factor was the main determinant of biological protection factors with correlation coefficients of 0.81 for UPF (erythema), 0.77 for NMSC, and 0.63 for photoimmunosuppression. Water or sweat humidity saturation increased biological protection factors over a 20% (P < 0.05). The 83% of the fabrics analyzed showed less than 5% of transmittance with labeling as UVA protective elements. No effect of fabric color was found related to biological protection factors. The 100% polyester sports T-shirts of the analyzed sample offer general protection against UV for different biological effects that can be increased by humidity but no affected by fabric color.     

A very practical and selective method for PMB protection of alcohols

A very simple, practical and efficient one-step heterogeneous protocol for the PMB protection of alcohols using Amberlyst-15 has been developed. The stability and hazard issues regarding PMBCl and PMBBr are totally avoided by directly using anisyl alcohol for the protection. Alcohols are protected in very good yields. The selective mono-PMB protection of diols as well as di-PMB protection of diols was achieved in good yields, along with the demonstration of recyclability of the catalyst.     

Electroactive conducting polymers for corrosion control

This paper reviews the literature describing the effects of conducting polymer coatings on the corrosion rate of ferrous alloys (iron, steel and stainless steel). The literature is interpreted in terms of the proposed mechanisms of corrosion protection: barrier, inhibitor, anodic protection and the mediation of oxygen reduction. The most intriguing aspect of the reported literature are the studies demonstrating corrosion protection when deliberate defects were introduced into the coating to expose the bare metal. These studies show that protection afforded by conducting polymer coatings is not due to simple barrier protection or inhibition alone. Many studies illustrate that the polymer/metal interface is modified to produce passivating oxide layers and that charge transfer reactions occur between the metal and polymer. These studies support the proposed anodic protection mechanism, as do the reports of significant ennoblism. On the other hand, there is considerable variation in the reported shift in corrosion potential and these highlight the influence of substrate preparation, coating composition and mode of application and the nature of the electrolyte on the corrosion protection provided by the conducting polymer. For example, the evidence suggests that the emeraldine base form of polyaniline is superior to the emeraldine salt in terms of corrosion protection for steel. However, the number of direct comparisons is small and the reasons for the differences are not well understood. Also not well understood are the role of the counterion release and local pH changes on pinhole protection. It is also argued that the conducting polymer reduces the likelihood of large increases in pH at the polymer/metal interface and so stabilizes the coating against cathodic disbondment. Further work is clearly needed to increase the protection period by further studies on the corrosion protection mechanism so that the polymer composition and processing methods may be optimized.     

实验室安全环保意识的调查与分析——以中山大学化学类专业学生为例

A survey about students' laboratory safety and environmental protection consciousness was performed in the freshmen majored in chemistry at Sun Yat-Sen University. Results showed that laboratory safety and environmental protection consciousness of most students' are weak. After analyzing the reasons, we put forward some suggestions. Cultivating students' laboratory safety and environmental protection consciousness should be carried out from several aspects such as emphasizing and regulating from school level, training in laboratory teaching, maintaining good cultural atmosphere of laboratory, as well as providing perfect laboratory safety and environmental protection facilities. We should guide students to actively learn knowledge and skills of laboratory safety and environmental protection in order to develop their good behavior and raise their consciousness.     

New Advances in Protection Against Solar Ultraviolet Radiation in Textiles for Summer Clothing

Clothing is considered one of the most important tools for photoprotection against harmful solar ultraviolet radiation (UVR). The standard for sun‐protective clothing is based on erythema despite other biological effects of UVR on the skin. We analyzed the potential protection against UVR in fabrics destined for summer clothing based on several action spectra. We examined 50 garments classified by type of fabric composition, structure of the fiber yarn and color. The ultraviolet protection factor was calculated based on fabric ultraviolet transmittance corrected for erythema according to the EU standard E‐13758 as well as the UVA transmittance of fabrics. UVR protection was also analyzed in base of different action spectra as for previtamin D3, nonmelanoma skin cancer, photoimmunosuppression and photoaging. Most knitted fabrics used for sports T‐shirts offered excellent ratings for ultraviolet protection while normal shirts showed very low ratings, particularly against photoaging. The cover is the most influential variable in fabric photoprotection, having an exponential relationship with the UPF. The relation between cover and UVA protection was linearly negative. Information about ultraviolet protection in textiles used for summer clothing should be included in labeling as some types of fabrics, especially those used for shirts, offer very low UVR protection.     

磷铁粉替代环氧富锌底漆中部分锌粉的耐腐蚀性能影响研究

本文主要探讨采用磷铁粉替代环氧富锌底漆中部分锌粉所制备的环氧富锌底漆的耐腐蚀性能。磷铁粉替代锌粉的质量百分数从0到75%,采用电化学方法和盐雾试验以及结合能谱仪(EDS)和扫描电镜(SEM)评价各涂层的耐腐蚀性能。结果表明低替代量的环氧富锌底漆阴极保护能力强,而高替代量的环氧富锌底漆有优异的屏蔽作用。替代量为35%的环氧富锌底漆对样板兼具良好的阴极保护和屏蔽作用,防腐蚀性能优异。     

Attitudes,Beliefs, and Measures Taken by Parents to Protect Their Children from the Sun in Guangzhou City,China

Excessive sun exposure can cause sunburn, suntan, skin photoaging, and even skin cancer. Skin photoaging conflicts with the human pursuit of a young and beautiful appearance. Some research data indicate that the incidence of skin cancer in the Chinese has been increasing, although it remains lower than in whites. To estimate the prevalence of sun protection used on Chinese children aged 3–13 years and identify its predictors, a population‐based cross‐sectional questionnaire was given to 3684 parents/guardians of children in Guangzhou, China, of which 3083 questionnaires were returned. Of those returned, 35.5% of parents/guardians reported regularly using sun protection on their children and the primary reason cited was to prevent sunburn. Hats and handheld umbrellas were the most frequently used measures; sunscreen was less common, and when used, 48.8% of parents/guardians still reapplied sunscreen on their children every 2.0–3.0 h. Parental age, parents using sun protection measures themselves when outdoors, and the child's sex were factors associated with regular use of sun protection on children. These results suggest that sun protection campaigns targeted toward parents and children need to be conducted in Guangzhou, or throughout China, to strengthen awareness about sun protection and address any inadequate protocols of sun protection.