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21.
Benzene oxide (BO) reacts with cysteinyl residues in hemoglobin (Hb) and albumin (Alb) to form protein adducts (BO-Hb and BO-Alb), which are presumed to be specific biomarkers of exposure to benzene. We analyzed BO-Hb in 43 exposed workers and 42 unexposed controls, and BO-Alb in a subsample consisting of 19 workers and 19 controls from Shanghai, China, as part of a larger cross-sectional study of benzene biomarkers. The adducts were analyzed by gas chromatography-mass spectrometry following reaction of the protein with trifluoroacetic anhydride and methanesulfonic acid. When subjects were divided into controls (n = 42) and workers exposed to < or =31 (n = 21) and >31 p.p.m. (n = 22) benzene, median BO-Hb levels were 32.0, 46.7 and 129 pmol/g globin, respectively (correlation with exposure: Spearman r = 0.67, P < 0.0001). To our knowledge, these results represent the first observation in humans that BO-Hb levels are significantly correlated with benzene exposure. Median BO-Alb levels in these 3 groups were 103 (n = 19), 351 (n = 7) and 2010 (n = 12) pmol/g Alb, respectively, also reflecting a significant correlation with exposure (Spearman r = 0.90, P < 0.0001). The blood dose of BO predicted from both Hb and Alb adducts was very similar. These results clearly affirm the use of both Hb and Alb adducts of BO as biomarkers of exposure to high levels of benzene. As part of our investigation of the background levels of BO-Hb and BO-Alb found in unexposed persons, we analyzed recombinant human Hb and Alb for BO adducts. Significant levels of both BO-Hb (19.7 pmol/g) and BO-Alb (41.9 pmol/g) were detected, suggesting that portions of the observed background adducts reflect an artifact of the assay, while other portions are indicative of either unknown exposures or endogenous production of adducts.   相似文献   
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Ethnopharmacological relevance

Bowdichia virgilioides Kunth (Leguminosae Papilonoideae) is a plant with anti-inflammatory activity used in folk medicine. The importance of this plant promoted its inclusion in Brazilian Pharmacopoeia.

Aim of the study

In order to evaluate the actions of this plant, studies were performed on antinociceptive and anti-inflammatory activities.

Materials and methods

The aqueous extracts (AE) of Bowdichia virgilioides inner bark and leaves were used at 100, 200, and 400 mg/kg. Antinociceptive activity of plant extract was evaluated by writhing, hot-plate and formalin tests. Anti-inflammatory activity was evaluated using paw oedema and peritonitis methods.

Results

Oral treatment with the AE of inner bark or leaves elicited inhibitory activity (P < 0.01) on acetic acid effect at 200 and 400 mg/kg, and reduced the formalin effect at the second-phase (200 and 400 mg/kg, P < 0.01), however it did not elicit any inhibitory effect on hot-plate test. The indomethacin inhibited the acetic acid-induced writhing and the formalin effect at the second-phase (P < 0.001), and the morphine reduced the both phases of formalin test (P < 0.001). Carrageenan-induced oedema formation and neutrophil migration into the peritoneal cavity were reduced with the AE of inner bark or leaves at 100, 200, and 400 mg/kg (P < 0.05), and by the reference compounds aspirin (P < 0.001) and dexamethasone (P < 0.001), respectively.

Conclusions

The AE of Bowdichia virgilioides shows antinociceptive and anti-inflammatory activities, supporting the folkloric usage of the plant to treat various inflammatory diseases.  相似文献   
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Introduction

Humans are widely exposed to estrogenically active phthalates, parabens, and phenols, raising concerns about potential effects on breast tissue and breast cancer risk. We sought to determine the association of circulating serum levels of these chemicals (reflecting recent exposure) with mammographic breast density (a marker of breast cancer risk).

Methods

We recruited postmenopausal women aged 55 to 70 years from mammography clinics in Madison, Wisconsin (N = 264). Subjects completed a questionnaire and provided a blood sample that was analyzed for mono-ethyl phthalate, mono-butyl phthalate, mono-benzyl phthalate, butyl paraben, propyl paraben, octylphenol, nonylphenol, and bisphenol A (BPA). Percentage breast density was measured from mammograms by using a computer-assisted thresholding method.

Results

Serum BPA was positively associated with mammographic breast density after adjusting for age, body mass index, and other potentially confounding factors. Mean percentage density was 12.6% (95% confidence interval (CI), 11.4 to 14.0) among the 193 women with nondetectable BPA levels, 13.7% (95% CI, 10.7 to 17.1) among the 35 women with detectable levels below the median (<0.55 ng/ml), and 17.6% (95% CI, 14.1 to 21.5) among the 34 women with detectable levels above the median (>0.55 ng/ml; Ptrend = 0.01). Percentage breast density was also elevated (18.2%; 95% CI, 13.4 to 23.7) among the 18 women with serum mono-ethyl phthalate above the median detected level (>3.77 ng/ml) compared with women with nondetectable BPA levels (13.1%; 95% CI, 11.9 to 14.3; Ptrend = 0.07). No other chemicals demonstrated associations with percentage breast density.

Conclusions

Postmenopausal women with high serum levels of BPA and mono-ethyl phthalate had elevated breast density. Further investigation of the impact of BPA and mono-ethyl phthalate on breast cancer risk by using repeated serum measurements or other markers of xenoestrogen exposure are needed.  相似文献   
25.
0 引言 膝关节周围是骨原发恶性肿瘤的好发部位 .病变组织广泛侵袭 ,切除肿瘤造成骨与软组织缺损 ,各种重建方法都需最大限度地保留膝关节功能 .如何采取早期系统的康复治疗 ,是临床骨肿瘤保肢手术的重要内容 .1 对象和方法  1992 - 0 5 / 1999- 0 3,膝关节周围恶性骨肿瘤患者 6 4例接受保肢手术治疗 .男 38例 ,女 2 6例 ;骨肉瘤 5 2例 ,恶性骨巨细胞瘤 5例 ,尤文瘤 3例 ,母细胞瘤 2例 ,原发神经外胚层肿瘤 2例 .手术方式 :异体半关节移植术 37例 ;异体骨段移植术 16例 ;复合异体骨段的人工全膝关节表面置换术3例 ,动力旋转铰链式人工全…  相似文献   
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Glenohumeral joint: comparison of shoulder positions at MR arthrography   总被引:3,自引:0,他引:3  
Kwak  SM; Brown  RR; Trudell  D; Resnick  D 《Radiology》1998,208(2):375
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