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61.
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
62.
随着医疗设备的不断增加 ,对其进行科学的管理显得愈加重要.为次,我们设备处管理人员引进了 EASY医院固定资产信息管理系统. 相似文献
63.
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
64.
对28例严重脊柱侧凸患者行矫形手术,结果手术均获成功,松解术后1周行后路矫形内固定加植骨融合术,术后Cobb角平均为40.8°,侧弯矫正率平均为52.0%。术后随访6~30个月,均无并发症发生。提出在做好脊柱侧凸矫形手术常规护理的同时,加强患者心理、体位、呼吸、镇痛、排便等方面的舒适护理,可增强患者舒适感,为手术获得成功和患者顺利康复提供有力保障。 相似文献
65.
Repeated administration of the antimanic drug lithium (4 mEq/kg/day for 2, 4 or 6 days, i.p.) to rats produced a progressive decline and eventual depletion of dynorphin-A (1-8) (DYN) concentration whereas Met5-enkephalin (ENK) was only marginally decreased in the neurointermediate lobe of the pituitary (NIL). Administration of a neuroleptic haloperidol neither affected ENK and DYN levels nor influenced lithium-induced changes. The study reveals that lithium produces a preferential perturbation in the dynorphin system relative to the enkephalin system. These results taken together with other evidence, indicate that dynorphin is possibly coreleased with vasopressin following lithium administration and provide a pharmacological support to the previously described colocalization and corelease of these endogenous peptides in the NIL. 相似文献
66.
Wing‐Hong Li Moon‐Tong Cheung Candace N.S. Ho Ting‐Pong Fung Kai‐Ming Ko Kelvin K.W. Yau 《Surgical Practice》2007,11(4):138-143
Aim: To examine the survival benefit of liver and lung resection for colorectal metastasis and the potential prognostic factors that affect patient survival. Methods: All patients who had resection of lung or liver metastasis for colorectal metastasis in Queen Elizabeth Hospital, Hong Kong from 1995 to 2004 were retrospectively reviewed. The overall and disease‐free survival was analysed, in particularly between liver and lung metastasis. All factors that may have affected the survival were entered into Cox's proportional hazards regression model to identify significant variables associated with survival. Results: At 5 years, the overall survival of patients who had resection of lung and liver metastasis was 44% and 38%, respectively; the disease‐free survival was 26% and 24%, respectively. Overall and disease‐free survival of patients with resection of lung metastasis was comparable to those with resection of liver metastasis. The differentiations of primary tumour and time to metastasis were shown to be significant prognostic factors influencing overall survival. Those patients with systemic chemotherapy after resection of colorectal metastasis demonstrated a significantly higher probability of overall survival. Conclusion: Resection of lung and liver metastases from colorectal origin was safe and both procedures improved survival. The use of chemotherapy after resection of metastasis significantly improved the overall survival. 相似文献
67.
目的: 几乎没有研究报道妊娠高血压综合征 (妊高征 ) 患者尿蛋白对新生儿出生体重的影响, 该研究欲探讨妊高征患者不同水平尿蛋白对新生儿出生体重的影响关系。方法: 1997年 1月 ~2004年 6月期间, 住院分娩患中、重度妊高征产妇 136例, 对新生儿出生体重与各种因素进行回归分析及t检验分析。结果: 单变量回归分析尿蛋白、孕龄分别与新生儿出生体重有高度显著性关系 (P<0. 01); 尿蛋白和孕龄一起进入多元回归分析, 校正影响因素, 尿蛋白和孕龄仍然是影响新生儿出生体重显著性因素 (P<0 .01); 与妊高征尿蛋白 ( +) 比较, 尿蛋白 无显著性影响新生儿出生体重 (P>0. 05), 尿蛋白 有显著性影响新生儿出生体重 (P<0. 01)。结论: 新生儿出生体重与妊高征患者尿蛋白丢失有关, 尿蛋白 丢失将严重影响新生儿出生体重。 相似文献
68.
目的:采用直丝弓矫治器矫治成年患者骨性AngleⅡ类2分类错牙合,以研究正畸治疗前后牙、颌硬组织变化,评价正畸矫治效果。方法:本文选择了8例AngleⅡ类2分类错牙合成年患者,男3例,女5例,年龄19~27岁,平均23.6岁。拔除双侧上颌第一双尖牙,运用直丝弓矫治器进行治疗,拍摄治疗前后X线头颅定位侧位片,进行治疗前后的X线头影测量研究。结果:治疗后SNA角减小,ANB角减小,U1-SN角增大,L1-MP角增大,U1-L1角减小。上颌切牙牙根及上颌基骨明显腭向移动,减小了上颌骨突度;下颌切牙牙冠明显唇向倾斜,代偿了下颌骨后缩。结论:骨性AngleⅡ类2分类错牙合患者经过上颌拔牙矫治后,面形有所改善,取得了理想的矫治效果。 相似文献
69.
Hematopoietic effects in mice exposed to arsine gas 总被引:1,自引:0,他引:1
Arsine gas is a potent hemolytic agent. Concern about semiconductor workers prompted an in-depth study of arsine at the National Institute of Environmental Health Sciences to determine the hematopoietic effects of prolonged exposure to this gas. Female B6C3F1 mice were exposed by inhalation to 0, 0.5, 2.5, and 5 ppm arsine, 6 hr/day for 14 days. Body weights of exposed mice were comparable to those of controls, but a marked, concentration-related splenomegaly was observed. Higher level arsine exposure produced statistically significant decreases in red blood cells, hematocrit and hemoglobin, with increases in white blood cell counts and mean corpuscular volume of red blood cells. Erythropoiesis as measured by quantitation of erythroid precursors in culture revealed a marrow reduction of colony-forming unit erythroids/femur cells for all treated groups on Day 3 postexposure and only at the 5 ppm dose group on 24 days postexposure, while splenic erythropoiesis increased at higher concentrations of arsine. There was no alteration in bone marrow cellularity and a less significant effect on granulocyte-macrophage progenitors. A 12-week study of arsine at 0, 0.025, 0.5, and 2.5 ppm (6 hr/day) by inhalation showed similar effects on hematopoiesis in mice. In conclusion, arsine exposure at low concentrations produces a stress on the hematopoietic system characterized by hemolysis, which persists for a prolonged period following exposure. 相似文献
70.
目的 了解、观察葡立胶囊与抗骨增生胶囊联用治疗颈椎病对血清SOD含量及疼痛功能评分的影响。方法 对一组神经根型颈椎病患者,用葡立胶囊与抗骨增生胶囊联合应用治疗3个月,测定血清SOD含量及疼痛功能评分变化。结果 颈椎病患者治疗组血清SOD含量与治疗前相比明显升高,疼痛功能评分治疗前相比明显降低。结论 葡立胶囊与抗骨增生胶囊联合应用可明显缓解症状,提高血清SOD活力,延缓颈椎间盘退变,对治疗颈椎病有明显疗效。 相似文献