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21.
We report a case of an assisted pregnancy in an asymptomatic woman who was found to have an extrauterine mass on ultrasound and MRI. This complex mass had equivocal imaging features and was found to be a ruptured ovarian ectopic pregnancy at surgery. This case illustrates that vigilance is required regarding the possibility of coexisting ectopic and intrauterine pregnancy following assisted conception, even in entirely asymptomatic cases. 相似文献
22.
Determination of malondialdehyde-induced DNA damage in human tissues using an immunoslot blot assay 总被引:3,自引:4,他引:3
Leuratti C; Singh R; Lagneau C; Farmer PB; Plastaras JP; Marnett LJ; Shuker DE 《Carcinogenesis》1998,19(11):1919-1924
Malondialdehyde (MDA) is a product of lipid peroxidation and prostaglandin
biosynthesis. It is mutagenic and carcinogenic and the major adduct formed
by reaction with DNA, a highly fluorescent pyrimidopurinone (M1-dG), has
been detected in healthy human liver and leukocyte DNA. Analytical methods
used so far for the detection of M1- dG have not been applied to a large
number of individuals or variety of samples. Often, only a few microg of
DNA from human tissues are available for analysis and a very sensitive
assay is needed in order to detect background levels of M1-dG in very small
amounts of DNA. In this paper, the development of an immunoslot blot (ISB)
assay for the measurement of MI-dG in 1 microg of DNA is described. The
limit of detection of the assay is 2.5 adducts per 10(8) bases. A series of
human samples were analysed and levels of 5.6-9.5 (n = 8) and 3.1-64.3 (n =
42) of M1-dG per 10(8) normal bases were detected in white blood cell and
gastric biopsy DNA, respectively. Results on four human samples were
compared with those obtained using an HPLC/32P-post- labelling (HPLC/PPL)
method previously developed and indicated a high correlation between M1-dG
levels measured by the two assays. The advantages of ISB over other assays
including HPLC/PPL, such as the possibility of analysing 1 microg
DNA/sample and the fact that it is less time-consuming and laborious, means
that it can be more easily used for routine analysis of a large number of
samples in biomonitoring studies.
相似文献
23.
为了寻找毒性低、增敏作用强的乏氧细胞放射增敏剂,设计并合成了一系列5-溴-,5-甲基-,和5-未取代的3-硝基-1,2,4-三唑-1-乙酰胺类化合物,用HeLaS3细胞进行了体外试验。结果表明5-溴取代衍生物的增敏作用强于相应的5-甲基-或5-未取代的硝基三唑衍生物,但是它们的毒性亦增大。修饰1位乙酰胺侧链也可以改变化合物的增敏作用和亲脂性。在所测定的化合物中TA-101[2-(3-硝基-1-三唑基)乙酰胺]由于有高的增敏作用和低亲脂性,可能是一个有希望的放射增敏剂。 相似文献
24.
灯盏花素对豚鼠单一心室肌细胞ICa的抑制作用 总被引:25,自引:0,他引:25
目的:观察灯盏花素对豚鼠单一心室肌细胞钙离子电流(ICa)的影响。方法:应用全细胞膜片钳制技术。结果:灯盏花素能明显抑制心室肌细胞的Ca^2+通道,使ICa减小。此作用有明显的电压依赖性。在峰电流电压下作用最明显,而对其反转电位无明显影响。在指令电位0mV时,0.5mg%灯盏花素使ICa减小5.4%,1mg%灯盏花素使ICa减小22.9%(P〈0.01),2mg%灯盏花素使ICa减小45.0%(P 相似文献
25.
目的:应用功能磁共振成像观察脑卒中后及康复过程中,在相应脑内运动功能区激活的变化情况,探讨不同运动模式下皮质功能再塑的表现。方法:选取2003-02/10大庆油田总医院康复科住院的皮质下脑梗死患者8例,在发病后1周始进行连续两个月的康复。在康复前、康复1,2个月时运用Brunnstrom分级、Caroll上肢功能量表(0 ̄100分,评分越高功能越好)对其手功能进行评价,并采用GEMR/iHiSpeed1.5超导磁共振扫描机进行磁共振成像功能激发检查。患者用病手执行简单运动(快速连续的拇指与其他各指的对指动作)、随意运动(用病手摸不同形状的木块),获得脑功能激发图像,观察脑内相关功能区的激活情况。结果:8例受试者均进入结果分析。①康复后所有患者Brunnstrom分级和Caroll上肢功能评分均较康复前有明显改善。②病手简单运动时脑内相关功能区的激活情况:8例受试者7例在损伤后早期手指不能对指,所以没有激活;M1,SMA,PMA脑区和小脑呈现单侧激活-双侧激活-单侧激活的变化过程;随着运动功能恢复,脑内激活数目随时间呈下降趋势,几乎接近正常人脑功能表现。③病手随意运动时脑内相关功能区的激活情况:实验中发现引起的运动相关功能区的激发情况变化多样,规律性较差,但其中5例受试者表现出损伤后激发数目明显减少,许多对运动起决定性支配作用的功能区亦不激活;随着运动功能恢复,激发区数目呈上升趋势,同损伤后简单运动的激活表现。结论:①脑卒中后病手经过康复治疗简单运动恢复较好,康复治疗2个月后脑内运动功能相关区域激活的规律已同正常人。②脑卒中后病手随意运动恢复较困难,康复治疗后不如简单运动恢复好,脑内相关运动功能区激活无明显的规律性。随着运动功能的恢复,脑内相应的运动功能区激活增多。 相似文献
26.
定量组织速度成像技术评价阿霉素诱导兔心肌病模型:与常规经胸超声心动图比较 总被引:1,自引:0,他引:1
目的:采用定量组织速度成像技术评价阿霉素诱导兔心肌病模型,并与常规经胸超声心动图比较其评估优势。方法:实验于2005-06/2006-08在大连医科大学完成。①实验分组及处理:取纯种新西兰白兔22只,雌雄不限,随机分成阿霉素组12只,给予阿霉素每次2mg/kg,以1g/L耳缘静脉注射,每周1次,注射8周;对照组10只每周注射2mL/kg生理盐水,共8周。②实验评估:每周应用HPSonos5500型彩色多普勒超声诊断仪(美国Agilent公司生产)对两组兔心脏进行左室收缩末期和舒张末期内径明、室间隔厚度、E峰、射血分数、左室短轴缩短率等常规超声参数测量,使用GEVivid7型彩色多普勒超声诊断仪(美国GE公司生产)进行收缩期和舒张期峰值速度、收缩期加速度定量组织速度成像参数测定。结果:22只兔进入统计。①对照组1~12周各参数与阿霉素组基础状态下比较无明显差异(P>0.05)。②第4周阿霉素组二尖瓣环运动的平均收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P均<0.05)。③第7周阿霉素组二尖瓣环运动的收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P<0.01),E峰较基础状态明显减低(P<0.05)。④第8周阿霉素组二尖瓣环运动的收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P<0.01),E峰较基础状态明显减低(P<0.01),左室收缩末期和舒张末期内径明显增大(P<0.05)。⑤第12周阿霉素组二尖瓣环运动的收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P<0.01),左室收缩末期和舒张末期内径明显增大(P<0.01),室间隔厚度、左室后壁厚度明显变薄(P<0.05),射血分数、左室短轴缩短率和E峰明显减低(P<0.01)。结论:定量组织速度成像参数可有效评价阿霉素诱导心肌病模型兔心肌的病理变化,较常规超声参数更敏感。 相似文献
27.
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29.
Free fatty acids promote hepatic lipotoxicity by stimulating TNF-alpha expression via a lysosomal pathway 总被引:25,自引:0,他引:25
Feldstein AE Werneburg NW Canbay A Guicciardi ME Bronk SF Rydzewski R Burgart LJ Gores GJ 《Hepatology (Baltimore, Md.)》2004,40(1):185-194
Nonalcoholic fatty liver disease (NAFLD) is a serious health problem. Although NAFLD represents a form of lipotoxicity, its pathogenesis remains poorly understood. The aim of this study was to examine the cellular mechanisms involved in free fatty acid (FFA)-mediated hepatic lipotoxicity. FFA treatment of liver cells resulted in Bax translocation to lysosomes and lysosomal destabilization with release of cathepsin B (ctsb), a lysosomal cysteine protease, into the cytosol. This process was also partially dependent on ctsb. Lysosomal destabilization resulted in nuclear factor kappa B-dependent tumor necrosis factor alpha expression. Release of ctsb into the cytoplasm was also observed in humans with NAFLD and correlated with disease severity. In a dietary murine model of NAFLD, either genetic or pharmacological inactivation of ctsb protected against development of hepatic steatosis, liver injury, and insulin resistance with its associated "dysmetabolic syndrome." In conclusion, these data support a lipotoxic model of FFA-mediated lysosomal destabilization. 相似文献
30.
Abdulkarim AS Burgart LJ See J Murray JA 《The American journal of gastroenterology》2002,97(8):2016-2021
OBJECTIVES: Nonresponse or relapse of symptoms is common in patients with celiac disease treated with gluten free diet. Refractory sprue (RS) is defined as initial or subsequent failure of a strict gluten-free diet to restore normal intestinal architecture and function in patients who have celiac-like enteropathy. The aims of this study were: 1) to identify causes of persistent symptoms in patients referred with presumed diagnosis of nonresponsive celiac disease (NCD); and 2) to characterize patients with true RS. METHODS: Patients were identified who had been systematically evaluated for NCD between January 1997, and May 2001. Patient records and small bowel biopsy results were reviewed. RESULTS: A total of 55 patients were referred with a presumed diagnosis of NCD. Six did not have celiac disease and had other diseases responsible for their symptoms. Diarrhea, abdominal pain, and weight loss were the most common reasons for evaluation in cases of NCD, whereas weight loss, steatorrhea, and diarrhea were the most common presenting features of RS (nine patients). Of the 49 patients with celiac disease, 25 were identified as having gluten contamination. Additional diagnoses accounting for persistent symptoms included: pancreatic insufficiency, irritable bowel syndrome, bacterial overgrowth, lymphocytic colitis, collagenous colitis, ulcerative jejunitis, T-cell lymphoma, pancreatic cancer, fructose intolerance, protein losing enteropathy, cavitating lymphadenopathy syndrome, and tropical sprue. CONCLUSIONS: Based on this study, we conclude the following: 1) gluten contamination is the leading reason for NCD; 2) of NCD cases, 18% are due to RS; and 3) alternative diseases or those coexistent with celiac disease and gluten contamination should be ruled out before a diagnosis of RS is made. 相似文献