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81.
Frederica Perera Deliang Tang Robin Whyatt Sally Ann Lederman Wieslaw Jedrychowski 《Cancer epidemiology, biomarkers & prevention》2005,14(3):709-714
Polycyclic aromatic hydrocarbons (PAH), of which benzo[a]pyrene is a representative member, are combustion-related environmental pollutants and include known carcinogens. Laboratory animal studies indicate that the dose of PAHs to the fetus is on the order of a 10th that to the mother and that there is heightened susceptibility to PAH-induced carcinogenesis during the fetal and infancy periods. Carcinogen-DNA adducts, a measure of procarcinogenic genetic damage, are considered a biomarker of increased cancer risk. Here we compare the levels of benzo[a]pyrene-DNA adducts as a proxy for PAH-DNA damage measured in maternal blood and newborn cord blood obtained at delivery in four different populations of mothers (total of 867) and newborns (total of 822), representing a 30-fold range of exposure to ambient PAHs. The populations include residents in Northern Manhattan, participants in a study of the effects of the World Trade Center disaster, residents in Krakow, Poland, and residents in Tongliang, China. Mean adduct concentrations in both maternal and cord blood and the proportion of samples with detectable adducts, increased across the populations [Northern Manhattan < World Trade Center (WTC) < Krakow < Tongliang], consistent with the trend in estimated ambient exposure to PAHs (P < 0.001). For mothers, the means in the respective populations were Northern Manhattan (0.21 adducts per 10(8) nucleotides), WTC (0.23 adducts per 10(8) nucleotides), Krakow (0.28 adducts per 10(8) nucleotides), Tongliang (0.31 adducts per 10(8) nucleotides); the corresponding means in the newborns were Northern Manhattan (0.23), WTC (0.24), Krakow (0.29), Tongliang (0.31). The percentage of mothers with detectable levels of adducts in the respective populations were Northern Manhattan (36.8%), WTC (57.5%), Krakow (72.9%), Tongliang (73.4%); the corresponding percentages among the newborns were Northern Manhattan (42.4%), WTC (60.6%), Krakow (71.1%), Tongliang (79.5%). Despite the estimated 10-fold lower PAH dose to the fetus based on laboratory animal experiments, the adduct levels in the newborns were similar to or higher than in the mothers. This study suggests that the fetus may be 10-fold more susceptible to DNA damage than the mother and that in utero exposure to polycyclic aromatic hydrocarbons may disproportionately increase carcinogenic risk. The data support preventive policies to limit PAH exposure to pregnant women and children. 相似文献
82.
83.
D Yu 《中华耳鼻咽喉科杂志》1989,24(4):215-8, 254-5
Kanamycin (400 mg/kg) was injected daily for 5 days in guinea pigs, the changes in CM and AP responses were recorded. The CM threshold was elevated in 34.5% of the animals and the CM amplitude was reduced when compared with normal animals (P less than 0.005). The AP threshold was elevated in 13.8%. The latency of N1 was increased (P less than 0.001) and the amplitude of N1 reduced at 80 dB (S-L) (P less than 0.001).cAMP and cGMP levels in the organ of Corti and stria vascularis spiral ligament decreased, and the decrease correlated with the changes in auditory function. We consider the reduction of cyclic nucleotides in the cochlea may be important in kanamycin ototoxicity. 相似文献
84.
85.
Zusammenfassung GRUNDLAGEN: Das Ziel dieser Untersuchung war, die Machbarkeit und Wirksamkeit der Fokus-Sanierung via Mini-Thorakotomie zur Therapie einer kavernösen Lungentuberkulose zu prüfen. METHODIK: Der Mini-Thorakotomie-Zugang wurde in 18 Patienten angewendet (Alter, 25–75 Jahre; median, 47,5 Jahre). Die Patienten hatten eine kavernöse Lungentuberkulose oder ein Lungentuberkulom nach tuberkulostatischer Therapie oder waren Patienten, die auf diese Therapie nicht angesprochen haben. 8 Patienten mit chronischer kavernöser Lungentuberkulose und 10 Patienten mit Tuberkulom haben sich der Fokus-Sanierung, Spülung und Faltnaht unterzogen. ERGEBNISSE: Es gab keine operative Mortalität. Alle Patienten waren klinisch saniert, hatten keinen Nachweis für Bakterien im Sputum, im Röntgen hatten die Lungenschatten abgenommen. Die Dauer der Operation betrug 30–120 min (median, 75 min), der intraoperative Blutverlust war 100–200 ml (median, 153 ml). Der postoperative Spitalsaufenthalt betrug 21–42 Tage (median, 30 Tage). Das Follow-up nach 1–4 Jahren (median, 2,5 Jahre) zeigte keine Komplikation und kein Rezidiv der Grunderkrankung. SCHLUSSFOLGERUNGEN: MTFC ist eine sichere und technisch machbare Methode zur Therapie der Lungentuberkulose oder des Tuberkuloms bei Schonung der Lungenfunktion. 相似文献
86.
Neal M. Blitz DPM FACFAS Jonathan H. Yu BS 《The Journal of foot and ankle surgery》2005,44(3):218-221
Freiberg's infraction is an ostechondrosis of a lesser metatarsal head resulting in degeneration of the metatarsophalangeal joint. Several mechanisms have been suggested in its pathenogenesis. Freiberg first described the entity and believed single impact trauma was the underlying cause. Repetitive biomechanical microtrauma is the most widely accepted etiologic theory. Other factors contributing to its development include aseptic necrosis, ischemia, and a congenital predisposition. We present a case report of Freiberg's infraction occurring in identical twins involving multiple metatarsals in various stages of degeneration. One of the twins was affected unilaterally whereas the other twin was affected bilaterally. Both twins had involvement of the second metatarsal on the same side extremity. The occurrence of Freiberg's infraction in identical twins suggests that an underlying congenital predisposition to the condition may play more of a role than previously considered. 相似文献
87.
神经化组织工程骨构建的初步观察 总被引:16,自引:0,他引:16
目的评估两种组织工程骨体内神经化重建方法的成骨效果,研究神经化与成骨的相互关系。方法26只新西兰大白兔,其中24只随机分成四组:组织工程骨组(A组),感觉神经束植入组(B组),运动神经束植入组(C组),血管束植入组(D组);另2只为空白对照组。每只动物均制备左侧股骨长1.5cm的段缺性骨与骨膜缺损,钢板固定后骨缺损处分别植入用四种方法制备的组织工程骨。植入的神经分别是隐神经和股神经肌支。术后4、8、12周摄股骨正位X线片,用放射影像学评分和X线阻射影分析比较骨缺损修复情况。结果在组织工程骨中植入感觉神经束后,比单纯组织工程骨和运动神经束植入的修复效果均有明显提高,而在组织工程骨中植入运动神经束与单纯组织工程骨修复骨缺损的效果相比较无明显差异,感觉神经束植入与血管束植入的成骨效果比较无明显差异,血管束植入组的成骨效果优于其它两组。结论利用感觉神经束植入的方法可以提高组织工程骨的成骨作用,而植入运动神经束却无此作用。 相似文献
88.
Objective Sstudy effect of nuclear factor-κB ASOND on I type collagen expression and rat hepatic stellate cells(HSC)proliferation.Methods Rat HSCs were separated by affusing and digestingof Ⅳ type collagenenzyme and density acentric method.Lipid-mediated NF-κB p65 ASOND(0.001,0.01,0.1,1μmol/L)Was transferred into rat HSCs.Toxicity of HSCs caused by NF-κB p65 ASOND and activity of LDH were determined by trypan blue staining.Proliferation affection of transferring NF-κB p65 ASOND into HSCs was determined by MTT.In different concentration NF-κB p65 ASOND.expression of Ⅰ type collagen stimulated by 1mg/L TNF-αwas determined by RT-PCR and ELISA.Results After transfection of NF-κB p65 ASODN,expression of NF-κB protein in HSCs was decreasing.Toxicity experiment indicated that NF-κB p65 ASOND of different concentration(0.001,0.01,0.1 and 1.0 μmol/L)had no effect on HSCs livability and LDH activity(P<0.05).Four different concentration NF-κ B p65 ASOND could restrain HSCs proliferation stimulated by 1 mg/L TNF-α.The expression of I type collagen and mRNA stimulated by 1mg/LTNF-αwas increased,and had a positive correlation with concentration(P>0.05).Conclusion NF-κB p65 ASOND may depress NF-κB activity to restrain HSCs proliferation and Ⅰ type collagen expression,and reduce extracellular matrix. 相似文献
89.
Crohn病的CT表现 总被引:7,自引:1,他引:6
目的探讨Crohn病的CT表现特点。方法回顾性分析经病理证实的18例Crohn病的CT征象,大多数病例采用螺旋CT或多层螺旋CT扫描。结果所有病例均有节段性肠壁增厚,CT增强有7例表现为肠壁均匀增厚,缺乏层次,同时肠壁强化不明显;有11例表现为黏膜增厚和分层形成“靶征”和“双环征”,肠壁厚度多在5~10mm;有9例表现为病变段肠管周围纤维脂肪成分增多,蜂窝织炎及肠周或肠系膜血管增多增粗。有5例CT首先考虑为其他疾病,1例考虑为闭攀性肠梗阻,1例首先考虑为肠结核,2例回盲部病变怀疑为癌,1例肠穿孔形成脓肿仅诊为化脓性感染。结论cT不但能准确显示Crohn病肠壁、肠系膜及周围结构的异常,增强CT还能区分活动性与非活动性病变,有助于临床采取合理而积极的治疗方案。 相似文献
90.
目的 观察法国伊凡露皮肤填充材料用于除皱、填充凹陷性瘢痕及面部塑形的临床应用效果。方法将伊凡露注射于需填充的部位并适当塑形,运用X^2检验比较两组满意率的差异、受术者年龄别满意率差异。结果共120例受术者,术后随访18个月,总满意率为95.8%。两组各60例,术后满意率分别为96.7%和95%,两组问满意率差异及各组满意率与总满意率之间差异无显著意义;受术者年龄别满意率差异亦无显著意义。结论伊凡露皮肤填充材料用于注射填充面部皱纹和凹陷性瘢痕,操作简便,美容效果好,受术者满意率高。 相似文献