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1.
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response.  相似文献   
2.
The cellular infiltrate present in human diseased gingiva was analyzed in biopsies from 12 patients with gingivitis or periodontitis. The samples studied had been obtained in the course of surgery at inflammatory sites remaining after institution of periodontal treatment. Histological and immunological techniques were used to identify macrophages, B-cells, plasma-cells, T-cells and T cell subsets, as well as cells expressing class II HLA membrane antigens. T-cells appeared as the predominant population, but plasma-cells were also visualized in nearly all samples. Both OKT4+ and OKT8+ cells were seen in all cases, the latter being more numerous in periodontitis patients. Interdigitating-like cells were observed, positively labelled for class II antigens, as well as macrophages which were more numerous in periodontitis patients. These results suggest the participation of all components of the immune response in gingival disease, in a way resembling chronic recurrent inflammatory diseases.  相似文献   
3.
Facial hemiatrophies are anomalies of the first branchial arch and affect one in 4000-5000 newborns. Bone distraction is the technique of choice for the treatment of these dysmorphoses. Mandibular osteodistraction requires prior determination of the characteristics of the distraction vector whose three components will serve to activate the distractor. The patient, aged 5 years, presented with a right facial hemiatrophy, Grade IB according to the classification of Pruzansky. Tomodensitometric acquisition was obtained with a CT scanner. Software specifically designed for this application allows segmentation of the anatomical elements by a region-growing algorithm. The 3D representation of each element is added to a 3D scene, in which are placed the built-up landmarks necessary for the surgical simulation after 3D cephalometric analysis. The surgical cleavage plane is oriented according to the surgeon's requirements while preserving the predominant anatomical elements. The software allows performance of rotations and translations of the bone segments rendered independently from the cleavage plane. The distances and angles covered during the virtual movement are measured at its conclusion. The aim of moving the bone segments is to render the mandibular occlusion plane parallel to the reference occlusion plane. The vertical growth of the maxilla is realized by secondary recuperation. The distractor used was of an external multidirectional type allowing elongation of the mandibular ramus and mandibular corpus, closure of the goniac angle, and lateralization or medialization of the ramus. On the 15th day, the mandibular angle was reduced by 10 degrees, which allowed closure of the anterior gap and recentering of the incisive areas by a half-cuspid. The patient presented with a complex bone deficit in the three spatial directions, which allowed the development of software for modeling the distraction. Other clinical cases will be necessary to validate this 3D imaging-based technique.  相似文献   
4.
强脉冲光治疗浅表(皮肤)血管瘤临床观察   总被引:4,自引:4,他引:0  
目的:观察强脉冲光(IPL)治疗浅表(皮肤)血管瘤的疗效。方法:选择60例浅表(皮肤)血管瘤患者,随机分为治疗组和对照组,治疗组用535nm、580nm强脉冲光治疗皮损,每三周治疗一次,三次为一个疗程;对照组采用波长为532nm的Q开关Nd:YAG激光治疗,每两周治疗一次,三次为一个疗程。观察两组皮损的治愈率、并发症等情况,并行统计学处理。结果:治疗组皮损三次治愈率明显高于对照组(P〈0.01),患处瘢痕形成及炎症性色素沉着发生率均低于对照组。结论:强脉冲光(IPLTM)治疗浅表(皮肤)血管瘤效果满意。  相似文献   
5.
Several studies have been performed to examine the problem of diagnosing gastroduodenal reflux (GDR). No single method is widely accepted. The aim of this work was to evaluate the diagnostic value of gastric pHmetry in this regard. A gastric aspiration probe attached to a combined glass electrode was placed in the stomach of 24 patients, with its distal tip located between 9 and 12 cm below the cardia. One ml samples of gastric juice were taken from 8 of the patients every 30 min for 15 h and as well as, every time a spontaneous alkalinization (SA) (defined by a pH greater than or equal to 4 for at least 1 min) was observed. The pH of each sample was measured by colorimetry whereas the concentration of total biliary acids (CTBA) was evaluated by the fluorimetric method (Kit Sterognost 3 alpha Flu); pH value measured via the intragastric electrode during aspiration was also recorded (protocol A). Continuous gastric aspiration was carried out in the remaining 16 patients for the entire duration of the test (6 h) which was divided into periods of 20 min. Apart from the parameters evaluated during protocol A, the percentage of time during which the stomach had a pH greater than or equal to 4 was recorded, as well as the quantity of total biliary acids collected over the 20 min periods (protocol B). Correlation studies were carried out using the Kendall tau and Spearman tests. Percentages were compared using the chi 2 test.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
莫军成  陈默 《医学教育探索》2007,6(11):997-998,1012
可持续发展是人类反思人与自然关系的结果。可持续发展关键在于人。大学生是未来社会的中坚力量。通过高校道德教育这一途径,使可持续发展内化为大学生的道德发展要求,推进社会和谐发展。  相似文献   
7.
D-氨基酸氧化酶(DAAO)是两步酶法催化头孢菌素C(CPC)生成7-氨基头孢霉烷酸(7-ACA)的重要酶之一。利用固定化DAAO催化CPC的转化液中,酮酸中间体随批次的增加逐渐减少,反应至第13批时,转化基本完全。当转化液pH由7.2升至7.6时,终止反应,转化率和收率分别达99.6%和93%。分次补加固定化DAAO,可连续转化132批。  相似文献   
8.
静脉输液药物集中配置、管理是我国医院管理的一项新举措.长期以来,临床静脉输液中的加药工作一直是由护士在治疗室独立完成,这种方式存在着很多不足之处.在这种环境污染下,职业健康安全管理越来越受到各国政府的重视.为了提高服务质量,预防和控制可能存在的环境污染及职业健康安全风险,国家颁布 GB/T24001~ 1996<环境管理体系规范和使用指南>, GB/T28001-2001<职业健康安全管理体系规范>标准,引进国外的先进管理模式,此项工作由药师和护士共同完成,以期达到合理用药减少药物的流失和浪费,科学配置、降低输液反应.静脉药物配置中心把静脉药物配置从普通环境的治疗室转为在具有洁净条件的配置中心进行集中管理配置,保证配置出来的药品安全无菌、有效.需要输液的患者在舒适、整洁和安静的环境下进行输液,减少临床护理工作量的目的,把更多的时间还给病人.这为顺利实施静脉配置中心的项目提供了保障,确保了输液中心正常运行.  相似文献   
9.
Congenital disorders of glycosylation type I (GDG-I) is a class of genetic multisystem disorders characterised by defective glycosylation of glycoproteins. The characteristics and mechanisms of failure to thrive and intestinal diseases present in CDG-I are anectodal. PATIENTS AND METHODS: The aim of this study was to analyse 7 CDG-I (4 CDG-Ia, 2 CDG-Ib and 1 CDG-Ix) with important digestive symptoms and failure to thrive in order to characterise the mechanisms implied. RESULTS: Four children had no skin abnormality or dysmorphia (1 CDG-Ia, 2 CDG-Ib, 1 CDG-Ix). An encephalopathy with cerebellar hypoplasia was present only in the 4 CDG-Ia. Failure to thrive and diarrhea were present during the first month of life in 6 and appeared at 5 years in one CDG-Ia associated to mild or severe hepatopathy in all patients. One CDG-Ia, 1 CDG-Ib, 1 CDG-Ix had an exsudative enteropathy. A positive steatorrhea was present in 3 patients. Five patients had an abnormal small bowel biopsy. Abnormalities were variable: moderate inflammation of the chorion without villous atrophy in 2, intra-enterocyte fat accumulation without villous atrophy in 2, and partial villous atrophy with lymphangectasia in 1. In 2 CDG-Ia the intestinal biopsy was normal. Enteral nutrition in 4 and parenteral nutrition in 2 were effective in 4 patients and 1 patient with an exsudative enteropathy respond to a free fat diet (CDG-Ix). CONCLUSION: The digestive symptoms with failure to thrive is a common feature of CDG-I and could be the first symptoms. The diagnostic should be suspected if no other cause is found. Mechanisms of the intestinal symptoms appear to be multiple such as inflammation, abnormal enterocyte lipid transport or intestinal permeability related to the abnormal glycosylation of intestinal mucosa glycoproteins.  相似文献   
10.
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