变应性鼻炎脱敏治疗的效果观察

目的观察变应性鼻炎（AR）脱敏治疗的效果，探讨影响变应性鼻炎脱敏治疗效果的相关因素。方法对185例AR患者通过皮肤试验，选择敏感变应原浸液，按递增剂量进行常规皮下脱敏治疗。根据患者治疗前后的症状和体征得分情况，分为显效、有效和无效。选择性别、年龄、病程、病情、伴慢性鼻窦炎、伴哮喘、脱敏治疗时间、皮试反应等8个影响变应性鼻炎脱敏治疗效果的可能因素进行多元回归分析，筛查影响脱敏治疗效果的因素。结果总有效率74．6％，其中显效22．9％，有效51．7％。影响脱敏治疗效果的主要因素是治疗时间，即时间越长，效果越好（P〈0．01）；其次是年龄因素，年龄越小，效果越好（P〈0．05）；伴慢性鼻窦炎和伴哮喘也可能影响脱敏治疗效果（P值分别为0．072和0．069）。结论变应性鼻炎脱敏治疗是有效的，脱敏治疗时间越长、年龄越小，效果越好。     

The relationship between socioeconomic status, ethnicity, and cigarette smoking in urban adolescents

BACKGROUND: This study examined the relationship between community-level and school-level socioeconomic status indicators and current cigarette smoking among urban adolescents, and examined whether the socioeconomic status-cigarette smoking relationship was similar for African Americans and Whites. METHODS: Participants were 3,813 seventh-graders recruited in a large school system in the United States. Independent variables included median income and mean education within zip codes of participants' residence, percentage of participants receiving lunch at reduced or no cost at school level, and ethnicity. The dependent variable was current smoking status (never smoked vs smoking one or more cigarettes per month). RESULTS: Whites were significantly more likely than African Americans to smoke cigarettes. There was a main effect of education and lunch at reduced or no cost on cigarette smoking. Mean education by zip code was inversely associated with cigarette smoking, and lunch at reduced or no cost was directly associated with cigarette smoking. There was a significant interaction between income and ethnicity. Median income by zip code was directly associated with cigarette smoking among African Americans. CONCLUSIONS: Our findings suggest that smoking prevention efforts in this population should take both socioeconomic status and ethnicity into account.     

Assessment of the risk of heat disorders encountered during work in hot conditions

OBJECTIVE: To co-ordinate the work of the main European research teams in the field of thermal factors in order to develop and improve significantly the methods presently available for assessing the risks of heat disorders encountered during work in hot conditions. METHOD: Each item from the required sweat rate model was reviewed on the basis of the most recent literature. A database with 1,113 laboratory and field experiments, covering the whole range of hot working conditions, was assembled and used for the validation. RESULTS: Influence of clothing ensemble on heat exchange: methods and formulas were developed that take into account the dynamic effects associated with forced convection and the pumping effect associated with body movements and exercise. Prediction of the average skin temperature: the model used in the required sweat rate standard ISO 7933 was extended to cover more severe conditions with high radiation and high humidity and different clothing and take into account the rectal temperature for the prediction of the skin temperature. Criteria for estimating acceptable exposure times in hot work environments: criteria were reviewed and updated concerning the maximum increase in core temperature and the acceptable water loss, for acclimatised and nonacclimatised subjects. These limits are intended to protect 95% of the population. Measuring strategy: a strategy was developed to assess the risks in any working situation with varying conditions of climate, metabolic rate or clothing. A detailed methodology was developed in three stages: an "observation" method for the recognition of the conditions that might lead to thermal stress; an "analysis" method for evaluating the problem and optimising the solutions; and an "expert" method for in-depth analysis of the working situation when needed. Validation: the different results were used to prepare a revision of the interpretation procedure proposed in the ISO standard 7933. We validated the modified approaches using the database. This involved the whole range of conditions for which the model was extended, namely conditions with high and low radiation, humidity and air velocity as well as fluctuating conditions. Based on these results, the predicted heat strain model was developed: it is presently proposed as an ISO and CEN standard.     

Noninvasive native fluorescence imaging of head and neck tumors

Fluorescence images were acquired from ex vivo head and neck tumor specimens. The excitation and emission wavelength combinations were selected to image emission from native tissue fluorophores (collagen, tryptophan, elastin and nicotinamide adenine dinucleotide). Two dimensional intensity ratio maps were generated from the fluorescence images and compared to histology images. The ratio maps accurately distinguished the regions of tumor from normal tissue in the specimens. Additional features, such as collagen capsules, blood vessels, mucus glands and muscles were evident in the fluorescence images.     

下肢骨肉瘤的MRI与X线对照研究

目的 对比分析下肢骨肉瘤的X线与MRI表现，探讨MRI对骨肉瘤的诊断价值。方法 收集经手术或病理穿刺活检证实的下肢骨肉瘤15例，男11例，女4例，均行MRI平扫及增强扫描（4例行CT扫描），并摄有X线平片，对其MRI征象与X线征象作逐一对比。结果 MRI及X线平片对下肢骨肉瘤的诊断准确率均为100％，MRI在显示病变范围、放射状骨针、Codman三角两层结构以及跳跃病灶等方面明显优于X线平片检查。结论 X线平片是诊断骨肉瘤最简便而实用的方法，但MRI可以更好的显示病变的范围，发现早期病变。     

头皮原发性皮肤神经节细胞瘤

神经节细胞瘤是一种神经内分泌肿瘤，其发生与自主神经系统的交感或副交感神经节有关。罕见发生于膀胱、前列腺和子宫。本文作者报道1例发生于儿童头皮的原发性皮肤神经节细胞瘤。对此肿瘤进行了组织学、免疫组化和超微结构研究。该病例可能代表神经嵴细胞向鳃弓发育过程中的一种异常迁移。此外，研究结果还强调在胚胎发育过程中神经嵴和鳃弓／裂之间有复杂的相互作用。     

一例AML中一种新的TCRδ基因重排及其分析方法

Ｔ细胞抗原受体（ＴＣＲ）功能的表达有赖于该基因在正常Ｔ淋巴细胞发育过程中的重排。近年来，已发现一些肿瘤及白血病中出现该基因的异常重排。我们采用聚合链反应（ＰＣＲ）、“磁珠”固相纯化方法和ＰＣＲ产物直接测序等方法，从一例ＡＭＬ中发现了一种在白血病中未报道过的ＴＣＲδ基因重排，该重排是一种新报道的Ｄδ区ＤδＸ片段的重排，为ＤδＸＤδＤδＪδ不完全重排。在研究白血病ＴＣＲ基因重排中，采用本文所报道的方法     

Epogam evening primrose oil treatment in atopic dermatitis and asthma

Essential fatty acids are claimed to have positive effects in atopic diseases. In a double blind, placebo controlled, parallel group study 58 out of 60 children, with atopic dermatitis and the need for regular treatment with topical skin steroids, completed a 16 weeks' treatment period with either Epogam evening primrose oil or placebo capsules. Twenty two of these subjects also had asthma. The parents used diaries to record symptom scores and concomitant medication. Peak expiratory flow was measured and disease activity was monitored by the clinician every four weeks. The plasma concentrations of essential fatty acids increased significantly in the group treated with Epogam capsules. The study demonstrated significant improvements of the eczema symptoms but no significant difference was found between the placebo and the Epogam groups. No therapeutic effect was shown on asthma symptoms or fidget.