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81.
Ardawi MS Nasrat HA Rouzi AA Qari MH Al-Qahtani MH Abuzenadah AM 《BJOG : an international journal of obstetrics and gynaecology》2007,114(11):1397-1401
Objective To investigate the influence of cigarette or sheesha smoking on first-trimester markers of Down syndrome.
Design A prospective observational study.
Setting Primary care centres and antenatal clinics of Maternity and Children Hospital, King Abdulaziz University Hospital and New Jeddah Clinic Hospital, Jeddah, Saudi Arabia.
Population Women with a singleton pregnancy who were either nonsmokers ( n = 1736) or cigarette smokers ( n = 420) or sheesha smokers ( n = 181).
Methods Fetal nuchal translucency thickness (fetal NT), maternal serum free beta-human chorionic gonadotrophin (free β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) were measured at 11 weeks 0 days to 13 weeks 6 days of gestation in all women. Women were grouped according to smoking status, confirmed by maternal serum cotinine measurements, and analyte levels between groups were compared.
Main outcome measures Fetal NT, maternal serum free β-hCG, PAPP-A and cotinine measurements.
Results Compared with nonsmoking women, fetal NT was significantly increased and free β-hCG and PAPP-A levels were significantly decreased in both cigarette and sheesha smokers. There were significant relationships between all three markers and the number of sheeshas consumed per day.
Conclusions Cigarette and sheesha smoking significantly affect first-trimester markers of Down syndrome (fetal NT, free β-hCG and PAPP-A). Correction for this effect in women who smoke might improve the effectiveness of first-trimester screening for Down syndrome in these women. The underlying mechanism(s) relating smoking to the changes in first-trimester markers require further studies. 相似文献
Design A prospective observational study.
Setting Primary care centres and antenatal clinics of Maternity and Children Hospital, King Abdulaziz University Hospital and New Jeddah Clinic Hospital, Jeddah, Saudi Arabia.
Population Women with a singleton pregnancy who were either nonsmokers ( n = 1736) or cigarette smokers ( n = 420) or sheesha smokers ( n = 181).
Methods Fetal nuchal translucency thickness (fetal NT), maternal serum free beta-human chorionic gonadotrophin (free β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) were measured at 11 weeks 0 days to 13 weeks 6 days of gestation in all women. Women were grouped according to smoking status, confirmed by maternal serum cotinine measurements, and analyte levels between groups were compared.
Main outcome measures Fetal NT, maternal serum free β-hCG, PAPP-A and cotinine measurements.
Results Compared with nonsmoking women, fetal NT was significantly increased and free β-hCG and PAPP-A levels were significantly decreased in both cigarette and sheesha smokers. There were significant relationships between all three markers and the number of sheeshas consumed per day.
Conclusions Cigarette and sheesha smoking significantly affect first-trimester markers of Down syndrome (fetal NT, free β-hCG and PAPP-A). Correction for this effect in women who smoke might improve the effectiveness of first-trimester screening for Down syndrome in these women. The underlying mechanism(s) relating smoking to the changes in first-trimester markers require further studies. 相似文献
82.
A. Fagotti F. Fanfani A. Ercoli† L. Patrizi† S. Mancuso† & G. Scambia† 《International journal of gynecological cancer》2004,14(5):852-859
The objective was to assess the feasibility, the operative and postoperative outcome, and complications in the use of minilaparotomy for type II and III radical hysterectomy (RH) and pelvic lymphadenectomy (PLN) in early-stage cervical/endometrial cancer. A pilot study on 91 consecutive patients submitted to type II and III RH and PLN for early-stage cervical/endometrial cancer was performed between March 2002 and May 2003 in the Division of Gynecologic Oncology (UCSC, Rome). Thirty-two of 91 cases (35.2%) were eligible for minilaparotomy. The mean operative time was 156.7 min, whereas the mean intraoperative estimate of blood loss was 303.7 ml. A mean number of 32.7 pelvic lymph nodes and 6.2 common iliac nodes were removed. Ileus and removal of bladder catheter were on mean postoperative day 2.4 and 3.4, respectively. The mean number of postoperative days spent in the hospital was 3.7. Intra- and postoperative parameters were compared to laparotomy controls and literature data on laparoscopy and Pfannenstiel incision, showing substantially comparable results. Minilaparotomy is acceptable for selected patients undergoing radical abdominal hysterectomy (RAH) and PLN and does not compromise the adequacy of the procedure. It can be considered as an alternative to the classic midline vertical incision or even to the Pfannenstiel incisions and laparoscopy. 相似文献
83.
Toxic effects of Fusarium mycotoxin butenolide on rat myocardium and primary culture of cardiac myocytes. 总被引:1,自引:0,他引:1
Jing-Bo Liu Yi-Mei Wang Shuang-Qing Peng Gang Han Yan-Sheng Dong Hai-Ying Yang Chang-Hui Yan Guo-Qiang Wang 《Toxicon》2007,50(3):357-364
Mycotoxin toxicosis has been implicated in the etiopathogenesis of Keshan disease (KD), an endemic cardiomyopathy prevailing in some regions of China. Butenolide (4-acetamido-4-hydroxy-2-butenoic acid gamma-lactone, CAS No. 16275-44-8), a mycotoxin produced by several Fusarium species such as Fusarium tricinctum and Fusarium graminearum, is frequently detected from the cereals in the endemic areas of KD. The present study is undertaken to investigate whether this mycotoxin can induce myocardial damage. Exposure of primary culture of cardiac myocytes to butenolide resulted in significant cytotoxicity, manifested by changes in cell morphology and decreases in cell viability. Consistent with the in vitro findings, distinct myocardial toxicity in vivo was observed after administration of rats by gavage with butenolide (10 and 20 mg/kg/day) for 2 months, and the myocardial injuries were characterized by focal necrosis of myocardium and fragmentation of myofiber. Butenolide also induced significant oxidative damage to the myocardium in vitro evidenced by a concentration-dependent lipid peroxidation in the myocardial homogenates, whereas antioxidants superoxide dismutase (SOD), N-acetylcysteine (NAC) and glutathione (GSH) provided significant protections against this oxidative effect. Taken together, these results clearly reveal that butenolide possesses the potential to induce myocardial toxicity. The present findings may reinforce the hypothesis that toxicosis by mycotoxins is one of the etiological factors for KD. 相似文献
84.
G Ferretti T Bacchetti R A Rabini A Vignini L Nanetti C Moroni L Mazzanti 《Diabetic medicine》2006,23(7):808-813
BACKGROUND: Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. AIM: The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. METHODS: The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quantifying the increase in sulphydryl groups (-SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. RESULTS: The increase in -SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P < 0.001). In addition, peroxynitrite production from HAEC incubated with Hcy-LDL from diabetic patients was greater than after incubation with Hcy-LDL from control subjects and untreated LDL from diabetic patients (P < 0.001). CONCLUSIONS: These results show that LDL from diabetic patients is more susceptible to in vitro homocysteinylation than LDL from non-diabetic individuals and demonstrate that the compositional changes in Hcy-LDL from diabetic subjects have cytotoxic effects on human endothelial cells. 相似文献
85.
86.
直接用木瓜蛋白酶水解软骨,三氯醋酸除蛋白质,乙醇沉淀干燥得硫酸软骨素粗多糖,经DEAE-Sepharose fast flow离子交换层析分离纯化,高效凝胶渗透色谱和琼脂糖凝胶电泳测定其相对分子质量和纯度,比较硫酸软骨素粗品和纯品的体外自由基清除活性。结果显示硫酸软骨素粗品和纯品提取率分别为31.56±0.46%和19.79±0.78%,后者相对相对分子质量为75 174,粗品的DPPH.和.OH清除活性最强,随着产品纯度的提高,活性降低,而对于O2-.清除活性结果则相反。 相似文献
87.
UVA对人角质形成细胞的氧化损伤作用 总被引:1,自引:0,他引:1
①目的 探讨紫外线A(UVA)对人角质形成细胞氧化损伤的机制。②方法 用 5J/cm2 UVA照射角质形成细胞 ,酶生化法检测活性氧 (ROS)的含量及超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH PX)活性的变化 ,流式细胞仪测定紫外线对角质形成细胞凋亡的影响 ,原位杂交技术观察 p2 1mRNA的变化 ,并与非照射组比较。③结果 与对照组比较 ,UVA照射组ROS含量升高 (t =113.6 8,P <0 .0 0 1) ,SOD、GSH PX活性下降 (t =5 7.2 3、19.0 4 ,P <0 .0 0 1) ,细胞凋亡率升高 (t=5 3.2 8,P <0 .0 0 1) ,p2 1mRNA表达增强。④结论 UVA对人角质形成细胞的损伤与氧自由基生成增多及细胞抗氧化能力抑制有关 相似文献
88.
次声90 dB和130 dB致大鼠肝细胞损伤的超微结构改变 总被引:2,自引:0,他引:2
目的:探讨相同频率(16 Hz)不同声压水平(90 dB与130 dB)次声作用下大鼠肝细胞超微结构损伤特点及意义.方法:将雄性SD大鼠66只,随机分为对照组(6只)、实验1(90 dB)和实验2(130 dB)组.根据次声作用时间,实验1,2组各分为1,7,14,21和28 d时间组,每组6只.在相同频率不同声压水平次声环境下每日暴露1次,每次2 h;取肝左右叶两个部位组织用戊二醛和锇酸固定,透射电镜下观察肝超微结构变化.结果:1 d组:90 dB环境作用下肝超微结构无明显损伤变化,130 dB环境作用下肝细胞内有脂滴出现;7,14和21 d组不同环境和天数次声作用后肝损伤出现脂滴逐渐增多和肝细胞部分变性坏死改变,发现肝细胞内的各种结构随次声作用次数增多其损伤程度逐渐加重;28 d组其损伤程度均有一定程度恢复.结论:次声下可以对肝细胞超微结构造成不同程度损伤,28 d后肝细胞对次声的损伤作用存在着一定适应现象. 相似文献
89.
高果糖诱导IR大鼠模型血清脂质代谢的改变及意义 总被引:4,自引:0,他引:4
目的: 评估高果糖膳食对机体胰岛素敏感性及血清脂质代谢的影响及意义.方法:以高果糖膳食(果糖占总热量34.5%)诱导并经钳夹技术证实建立胰岛素抵抗(IR)大鼠模型,生化比色法测定血清游离脂肪酸(FFA),生化酶法测定血清甘油三酯(TG)及总胆固醇(TC).结果:高果糖膳食喂养4周后,实验组大鼠葡萄糖输注率由(11.5±0.6)mg/kg·min-1下降至(6.6±0.4)mg/kg·min-1(P<0.01);血清FFA由(0.45±0.09)mmol/L增至(0.78±0.19)mmol/L(P<0.01);TG由(0.54±0.10)mmol/L增至(0.96±0.22)mmol/L(P<0.01);TC由(1.96±0.32)mmol/L增至(2.42±0.21)mmol/L(P<0.01).结论:高果糖膳食可导致机体严重IR,是建立IR大鼠模型的有效手段;该模型同时伴有血清脂代谢各相关指标的明显异常,血脂的变化既是IR的结果,也是IR向纵深发展的原因和必要条件. 相似文献
90.
Péter Móricz Imre Gerlinger Jenő Solt Krisztina Somogyvári József Pytel 《European archives of oto-rhino-laryngology》2007,264(12):1441-1445
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy
and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic
balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases.
In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The
average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature
data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every
effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major
myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap
needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free
flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in
prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and
neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter
dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure
provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However,
a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion
of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications. 相似文献