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31.
通过实验证实,可用腐植酸(HA)代表天然水中三卤甲烷(THMs)的前体。单一模拟化合物(含一个活性空位碳原子的间苯二酚,三个活性空位碳原子的间苯三酚,及甲基酮类化合物的丙酮酸钠)氯化后氯信形成的规律与氯化HA的不一致。而间苯二酚与丙酮酸钠的混合物(1:4W/W)能很好地反映出HA中活性结构的特性。为今后研究THMs的形成提供了一个可资定量比较的THMs前体。 相似文献
32.
S. Peeters U. Blecker J. De Valck A. Goossens M. Hautekeete G. Devis Y. Vandenplas 《European journal of pediatrics》1993,152(2):107-109
We report a 12-year-old boy presenting with smooth muscle antibody-positive auto-immune chronic active hepatitis. Suspicion of the diagnosis arose after a routine blood test which revealed abnormal liver function tests. In spite of the presence of cirrhosis and patchy necrosis on liver biopsy, our patient never showed any clinical feature of impaired liver function. This observation demonstrates that auto-immune hepatitis may exist for a long time before clinical symptoms appear and probably explains why some cases of auto-immune hepatitis finally present as fulminant liver failure. 相似文献
33.
褪黑素对结肠黏膜上皮细胞氧化应激的影响 总被引:3,自引:1,他引:2
目的 探讨褪黑素对大鼠结肠黏膜上皮细胞氧化应激的影响。方法 在分离培养正常大鼠结肠黏膜上皮细胞基础上,利用FeSO4 H2O2产生*OH攻击制备结肠黏膜细胞氧化损伤模型,同时预先加入褪黑素并观察损伤减轻程度。实验设正常对照组、模型对照组、5-氨基水杨酸给药组(0.1mmol/L),褪黑素给药组(0.01、0.1、l.0mmol/L)。培养一定时间后,取上清测乳酸脱氢酶(LDH)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSHPx)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、一氧化氮(NO)和黏液含量。结果 模型组大鼠结肠黏膜上皮细胞:MDA、LDH和NO水平增高,CAT、GSHPX、SOD和黏液含量减少。不同剂量褪黑素呈剂量依赖性的减少LDH释放,抑制MDA和NO的形成,恢复黏液、CAT、GSHPX及SOD水平。结论 褪黑素对大鼠结肠黏膜氧化损伤具有保护作用。 相似文献
34.
V. DOvidio A. Aratari A. Viscido A. Marcheggiano C. Papi L. Capurso R. Caprilli 《Digestive and liver disease》2006,38(6):389-394
BACKGROUND: Mucosa-infiltrated granulocyte neutrophils are an early characteristic of inflammation and the main histological feature of active ulcerative colitis. Mucosal healing has recently been indicated as an important tool in the evaluation of response to treatment. While several studies have stressed the efficacy of granulocyte-monocyte-apheresis in inducing clinical remission in active ulcerative colitis, few data are available on mucosal features. AIM: Aim of this study was to assess the effects of granulocyte-monocyte-apheresis on clinical and mucosal features in patients with ulcerative colitis, dependent upon or refractory to steroids. MATERIAL AND METHODS: From April 2004 to April 2005, 12 patients (5 females, 7 males, mean age 49 years, range 33-71 years), with mild-moderate ulcerative colitis (six left colitis, six pancolitis) dependent/refractory upon steroids were enrolled. Each patient was treated for a 5-week period with five cycles of granulocyte-monocyte-apheresis. Patients were evaluated at baseline and 1 week after the last apheresis by means of Global Physician Assessment, quality of life features, laboratory tests (erythrocyte sedimentation rate, CRP, full blood count, faecal calprotectine), endoscopy and histology. RESULTS: At week 6 of follow-up, complete mucosal healing was observed in 3 out of 12 patients, partial mucosal healing in 8 patients and no change in 1 patient. Clinical response was complete in 8 out of 12 patients. CONCLUSIONS: These data suggest that granulocyte-monocyte-apheresis induces an improvement both in clinical and mucosal lesions in steroid-dependent/refractory ulcerative colitis. Of note, the reduction in granulocyte infiltration and the improvement in mucosal lesions are accompanied by a reduction in faecal calprotectine. 相似文献
35.
目的探讨全结直肠切除回肠贮袋肛管吻合术(ileal pouch-anal anastomosis,IPAA)后患者控便能力与肛管压力的关系。方法对16例患者行IPAA术,术后1个月、6个月、1年时随访控便能力,并检测肛管压力。结果12例获得随访,平均2.3(1.0~4.5)年,患者排便次数在术后1年时明显少于术前和术后1个月(P<0.05);肛管静息压和最大缩柞压在术后1个月、6个月时明显低于术前(P<0.05),但在术后1年时已有明显改善,与术前相似(P>0.05)。结论IPAA术后肛管压力的改变可能与患者的控便能力有关。 相似文献
36.
经电镜观察,慢活肝中主要为淋巴细胞及单核巨噬细胞浸润。淋巴细胞分3型,通过4种方式与肝细胞接触,可能代表杀伤肝细胞的动态过程。与肝细胞接触的主要为起细胞毒作用的T_8~+Ⅱ型淋巴细胞及单核巨噬细胞。多数T_4~+淋巴细胞为Ⅰ型淋巴细胞,可能为T辅助细胞。在肝细胞损伤中,淋巴细胞及单核巨噬细胞均起重要作用。 相似文献
37.
目的 :研究肺表面活性物质 (PS)治疗新生儿呼吸窘迫综合征 (NRDS)前后血管内皮分泌功能变化及可能的治疗机理。方法 :用PS制剂固尔苏治疗 18例NRDS患儿 ,于治疗前 3 0min ,治疗后 1、 6、 12、 2 4h ,用硝酸还原酶法测定NO (一氧化氮 )、放射免疫法测定ET (内皮素 )、 6 K PGF1α (6 酮前列环素 )。结果 :固尔苏治疗后患儿NO、 6 K PGF1α明显升高 ,ET明显下降 ,与治疗前比较有显著性差异 (P <0 0 1)。治疗后 1、 6、 12、 2 4hNO、6 k PGF1α、ET各组间两两比较无明显差异 (P >0 0 5 )。结论 :PS治疗NRDS的机理可能是通过改善血管内皮功能发挥作用 ,为用外源性NO吸入和静注前列环素辅助治疗NRDS提供可能的实验依据。 相似文献
38.
Diversion colitis refers to the inflammatory changes that occur in the defunctioned segment of the large intesting following diversion of the faecal stream. We report the histological features in the defunctioned rectums from seven patients: one each with severe constipation and Behcet's disease, two with Crohn's disease with rectal sparing and three with ulcerative colitis. The appearances of diversion colitis in a previously normal rectum are compared with diversion colitis with superimposed inflammatory bowel disease. Lymphoid follicular hyperplasia was found in all cases. This was marked in patients with inflammatory bowel disease. with or without initial rectal involvement. Other changes comprised surface epithelial degeneration and ulceration, mucosal inflammation including crypt abscesses, and crypt branching. Inflammatory and crypt changes were mild, except in ulcerative colitis where changes were marked and resembled those of the proximal colon. Lymphoid hyperplasia is a distinctive feature in diversion colitis. The term follicular proctitis, previously used to indicate chronic ulcerative colitis exclusively, should be re-examined. 相似文献
39.
M.E. Traina P. Ade G. Siepi E. Urbani M.G. Petrelli 《International journal of environmental health research》1994,4(1):38-47
Experimental studies suggest that large numbers of chemicals, environmental and industrial pollutants affect the male reproductive system. At present, almost no information is available on the effects of these adverse agents on human reproduction. Recent reports, however, suggest that in the past 50 years male fertility has declined based on qualitative and quantitative measurements of normal sperm. This study identifies‐among the active ingredients and solvents included in pesticide formulations registered in Italy‐the chemical agents with experimental evidence of male reproductive toxicity. Documents produced by international agencies and organizations such as IARC, EPA, WHO, and original papers from the international literature were systematically reviewed. The results indicate that several pesticide products notified in the Italian Registry contain active ingredients and/or solvents severely affecting testicular function and sperm morphology in laboratory animals. Therefore, exposure to reproductive toxicants occurring among manufacturers and users of pesticide formulations registered in Italy suggest further epidemiologic surveys should be conducted in this area. 相似文献
40.
BARBARA A. LEGGETT RUSSELL J. COLLINS W. GRAHAM E. COOKSLEY ROGER L. PRENTICE LAWRIE W. POWELL 《Journal of gastroenterology and hepatology》1987,2(3):205-211
The aim of this study was to determine if the Crithidia luciliae assay for auto-antibodies to double-stranded DNA, often positive in systemic lupus erythematosus, is always negative in auto-immune chronic active hepatitis (CAH) as has recently been suggested. Twenty-five patients were identified as having auto-immune CAH. Mean duration of follow-up was 10.5 years. Antinuclear antibodies were detected in 92%, smooth muscle antibodies in 76% and antimitochondrial antibodies in 16%. Antibodies to double-stranded DNA were detected by the Crithidia assay in four patients (16%). Two of these patients had positive tests on only one occasion and no features of systemic lupus erythematosus. In the other two the assay was persistently positive. During follow-up both developed arthritis and serositis but the liver lesion remained the dominant clinical feature. It was concluded that there is significant serological overlap between auto-immune CAH and systemic lupus erythematosus making the Crithidia assay unreliable in distinguishing between them. 相似文献