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21.
目的:讨论萘对人体的慢性毒效应和亚临床客观检测指标。方法:对河南省萘暴露工人(环境接触萘浓度平均为8.25~26.43mg/m3)进行了健康监护和医学动态观察。结果:发现长期萘暴露工人的白细胞、血小板减少及眼晶体混浊检出率显著高于对照组(P<0.001);血清SOD同功酶、GSH-PX活性显著低于对照组,而LPO水平、神经元特异性烯醇化酶(NSE)活性水平以及外周血染色体畸变和微核阳性检出率均显著高于对照组(P<0.001)。神经行为功能检查结果,主要为消极情绪增加,记忆力下降等。事件相关电位P300峰潜伏期比对照组显著延长,与对照组差异显著(P<0.05)。结论:慢性低浓度萘暴露对工人主要损害部位(靶器官)有皮肤,眼、血液和神经组织等。NCTB、NSE、P300三项可作为早期神经受损的客观指标。 相似文献
22.
目的对腰骶神经根病患者的神经损伤程度与热成象体表温差的相关性进行研究。方法将100例腰骶神经根病患者按照热成象检查结果分为正常(23例)与异常(77例)两组。在热成象异常组中,根据临床病变程度并结合腱反射改变进一步划分神经损伤程度为轻(31例)、中(33例)、重度(13例)3组,比较3组的温差ΔT均值。结果热成象异常的轻、中、重3组温差ΔT均值分别为1.13±0.34,1.46±0.58和2.35±1.20(F检验P<0.0001)。各组间比较差异也均具有非常显著性意义。结论本研究结果提示神经损伤程度与体表温差具有相关性,即神经损伤程度愈重,患侧相应的体表温度愈低,温差越大。热成象具有对神经损伤程度进行初步定量评估的价值。 相似文献
23.
目的 评价和探讨修复骨外露及皮肤软组织缺损的各种方法 ,使其更好地用于临床。方法 3 5例不同部位的骨外露分别采用皮片移植、皮瓣及肌皮瓣转移、皮瓣及肌皮瓣游离移植等方法 ,覆盖外露的骨面。结果 3 1例全部存活 ,1例皮瓣部分坏死 ,2例创口延迟愈合 ,1例游离皮瓣失败。结论 对骨外露及皮肤软组织缺损应尽量在早期修复 ,最常用的方法是皮瓣及肌皮瓣的转移或移植。 相似文献
24.
多层螺旋CT胸部低剂量扫描对气道三维重建的应用研究 总被引:5,自引:1,他引:4
目的:比较低剂量与常规剂量条件下中央气道三维重建图像的差别,探讨低剂量螺旋CT扫描进行中央气道三维重建的可行性。材料和方法:32例病例行低剂量(50mAs)平扫及常规剂量(195mAs)平扫(1例)及增强扫描(31例),将两组原始数据分别普通算法及高分辨算法重叠重建出4组横断面图像,并进行气道SSD及VR重建,由两名放射科医师分析4组图像的质量、支气管显示情况、支气管病变检出情况,将结果进行统计学分析。结果:①图像质量:两组剂量间SSD图像质量无明显差异,高分辨重建图像质量≥普通算法重建图像质量;VR图像质量两种剂量之间无明显差异,高分辨算法图像质量≥标准算法重建图像质量。②支气管显示:两名医生评价结果均表明对段以上支气管显示方面无论SSD图像还是VR图像,低剂量与常规剂量组以及两种算法图像之间均无明显差异。③病变检出:无论SSD还是VR图像4组图像对支气管病变的检出无差异。④剂量差别:低剂量扫描比常规剂量扫描辐射剂量大大降低(13.6~3.6mGy)。结论:与常规剂量扫描相比,低剂量薄层扫描气道三维重建图像质量、对中央气道显示及病变检出都无明显差异,而病人接受的辐射剂量却大大降低,因此低剂量薄层扫描气道三维重建可以代替常规剂量重建图像应用于临床气道病变显示。 相似文献
25.
C. J. M. Antens M. Oldenwening A. Wolse U. Gehring H. A. Smit R. C. Aalberse M. Kerkhof J. Gerritsen J. C. de Jongste B. Brunekreef 《Clinical and experimental allergy》2006,36(12):1525-1531
BACKGROUND: Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. OBJECTIVE: We investigated the variability of house dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen in Dutch homes over a period of 8 years. METHODS: Data were obtained in the Dutch PIAMA birth cohort study. Dust from the child's mattress, the parents' mattress and the living room floor was collected at four points in time, when the child was 3 months, 4, 6 and 8 years old. Dust samples were analysed for Der p 1, Der f 1 and Fel d 1 by sandwich enzyme immuno assay. RESULTS: Mite allergen concentrations for the child's mattress, the parents' mattress and the living room floor were moderately correlated between time-points. Agreement was better for cat allergen. For Der p 1 and Der f 1 on the child's mattress, the within-home variance was close to or smaller than the between-home variance in most cases. For Fel d 1, the within-home variance was almost always smaller than the between-home variance. Results were similar for allergen levels expressed per gram of dust and allergen levels expressed per square metre of the sampled surface. Variance ratios were smaller when samples were taken at shorter time intervals than at longer time intervals. CONCLUSION: Over a period of 4 years, mite and cat allergens measured in house dust are sufficiently stable to use single measurements with confidence in epidemiological studies. The within-home variance was larger when samples were taken 8 years apart so that over such long periods, repetition of sampling is recommended. 相似文献
26.
L.A. Fischer T. Menné C. Avnstorp G.B. Kasting† J.D. Johansen† 《The British journal of dermatology》2009,161(3):560-567
Background Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) is a synthetic fragrance ingredient. Case reports of allergy to HICC appeared in the 1980s, and HICC has recently been included in the European baseline series. Human elicitation dose–response studies performed with different allergens have shown a significant relationship between the patch-test threshold and the repeated open application test (ROAT) threshold, which mimics some real-life exposure situations. Fragrance ingredients are special as significant amounts of allergen may evaporate from the skin.
Objectives The study aimed to investigate the relationship between elicitation threshold doses at the patch test and the ROAT, using HICC as the allergen. The expected evaporation rate was calculated.
Materials and methods Seventeen HICC-allergic persons were tested with a dilution series of HICC in a patch test and a ROAT (duration up to 21 days). Seventeen persons with no HICC allergy were included as control group for the ROAT.
Results The response frequency to the ROAT (in μg HICC cm−2 per application) was significantly higher than the response frequency to the patch test at one of the tested doses. Furthermore the response rate to the accumulated ROAT dose was significantly lower at half of the doses compared with the patch test. The evaporation rate of HICC was calculated to be 72% over a 24-h period.
Conclusions The ROAT threshold in dose per area per application is lower than the patch test threshold; furthermore the accumulated ROAT threshold is higher than the patch test threshold, which can probably be explained by the evaporation of HICC from the skin in the open test. 相似文献
Objectives The study aimed to investigate the relationship between elicitation threshold doses at the patch test and the ROAT, using HICC as the allergen. The expected evaporation rate was calculated.
Materials and methods Seventeen HICC-allergic persons were tested with a dilution series of HICC in a patch test and a ROAT (duration up to 21 days). Seventeen persons with no HICC allergy were included as control group for the ROAT.
Results The response frequency to the ROAT (in μg HICC cm
Conclusions The ROAT threshold in dose per area per application is lower than the patch test threshold; furthermore the accumulated ROAT threshold is higher than the patch test threshold, which can probably be explained by the evaporation of HICC from the skin in the open test. 相似文献
27.
Mortality rates in the Federal Republic of Germany following previous occupational exposure to asbestos dust 总被引:3,自引:0,他引:3
H. -J. Woitowitz H. -J. Lange L. Beierl M. Rathgeb K. Schmidt K. Ulm T. Giesen R. H. Wohowitz L. Pache K. Rödelsperger 《International archives of occupational and environmental health》1986,57(3):161-171
Summary In 1972, a procedure was introduced by the Industrial Injuries Insurance Institutes (Berufsgenossenschaften) of the Federal Republic of Germany, which is to be used by the special occupational health service for employees exposed to asbestos dust. Since 1 January 1972, occupational health examinations are performed when exposure to asbestos dust has been of at least 3 years' duration.On 1 January 1977, a prospective cohort study was started with employees formerly exposed to asbestos dust whilst working for companies manufacturing or using asbestos. Data on these persons are collected in the Central Register of Employees Exposed to Asbestos Dust of the Industrial Injuries Insurance Institutes. A total of 3,070 male and female employees in whom asbestos exposure terminated after 1 January 1972 formed subcohort I of the study. For comparison, 665 persons whose exposure terminated before 1 January 1972 served as subcohort II. In addition to several other inclusion criteria, each individual's permission was required before personal data could be evaluated.Of the subjects in the two subcohorts, 185 and 71, respectively, had died by 31 December 1982. Tumours were more frequently than this cause of death is expected in the general population. In addition to a high incidence of mesothelioma, the standard mortality rate was especially increased for lung cancer.The proportional mortality rates of about 40% for tumours of all sites (with about 17% lung cancer and 8% mesothelioma) especially in subcohort II, seemed to be comparable to the international figures for epidemiological mortality.Supported by the Central Office of the Industrial Injuries Insurance Institutes, Bonn, Contract no.638.31:376.3-4104.Presented as a Short Communication at the XXI International Congress on Occupational Health, Dublin, September 9–14, 1984. 相似文献
28.
目的为前臂肌腱部分移位修复桡尺远侧关节脱位提供解剖学依据。方法30侧成人上肢标本,将尺侧腕屈肌腱、尺侧腕伸肌腱、桡侧腕长伸肌腱、肱桡肌腱作形态学测量,将尺侧腕屈肌腱、尺侧腕伸肌腱进行力学测试。结果尺侧腕屈肌腱长(16.7±2.7)cm;尺侧腕伸肌腱长(14.9±2.5)mm;桡侧腕长伸肌腱长(19.0±2.0)cm;肱桡肌腱长(11.7±2.4)cm。力学测试:尺侧腕屈、伸肌腱其全肌腱破坏载荷分别为(2.4±0.9)Mpa、(3.1±0.9)Mpa,半肌腱破坏载荷分别为(2.2±0.9)Mpa、(2.5±0.8)Mpa,t检验无显著性差异。结论前臂肌腱部分转位有足够的长度和强度修复桡尺远侧关节脱位。 相似文献
29.
目的:探讨头皮电烧伤骨外露用头皮扩张皮瓣移植修复的临床效果。方法:采用早期扩创,保留部分坏死骨质,用邻近头皮扩张使带毛发的头皮面积扩大后移植覆盖创面,电性失活骨质在血循环良好的皮瓣覆盖下,为周边及基底健康骨质生长起到支架作用,皮瓣扩张到一定面积后移植到裸露骨质上,使其得以修复。结果:在治疗的9例中,除1例皮瓣边缘在1.5cm×1.5cm坏死外,其余皮瓣全部成活,未发生感染坏死,创面均一次性封闭。结论:头皮电烧伤骨外露扩张后皮瓣带毛发修复,可缩短创面愈合时间,外形较好,易掌握,效果较为满意。 相似文献
30.