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1.
Puja Vijay Parikh 《International journal of environmental health research》2016,26(4):458-466
Environmental chemical exposure could be an important etiologic factor for geographic differences in breast cancer incidence. In this study, we examined emissions of polycyclic aromatic hydrocarbons (PAHs) and PM2.5 in relation to breast cancer incidence in metro Atlanta and rural Georgia by analyzing data from the Surveillance, Epidemiology, and End Results Program and the Environmental Protection Agency. The results showed that metro Atlanta had a significantly higher age-adjusted annual incidence rate of female breast cancer than rural Georgia (132.6 vs. 113.7 per 100,000) for 1992–2011. Emissions of both PAHs [adjusted β = 0.568 (95 % CI: 0.209, 0.927); p = 0.004] and PM2.5 [adjusted β = 2.964 (95 % CI: 0.468, 5.459); p = 0.023] were significantly associated with breast cancer incidence in metro Atlanta area. This study suggests that ambient air pollution, especially PAHs and PM2.5, could have a significant impact on the increased incidence of female breast cancer in urban areas. 相似文献
2.
栀子临床应用广泛,且历史悠久,为更好地利用栀子资源,通过梳理历代文献与现代研究,对栀子名称、品种、产地、炮制、功效等方面进行考证,发现栀子命名主要以形态、色泽为依据,一定程度上反映了栀子的特征,并且存在与水栀子混用"黄栀"之名的情况。古代文献中记载的栀子产地最早为南阳,但产量不高,受人口迁移以及生产力发展的影响,栀子的产地主要转移到南方,且以南方产者为佳。在历代本草文献中记载入药用的栀子为山栀子,水栀子不堪入药,但在《伤寒论》等古代方书中有"肥栀子""大栀子"入药用的记载,通过后世对相应方剂的记载,确定二者应为水栀子,为水栀子的临床应用提供了有力依据。之所以与本草文献记载有所差异,应与《雷公炮炙论》和《伤寒论》的年代不同,栀子的产量及采收能力有所差距,且本草书重规范,择优入药,方书注重实用等特点有关,并且根据现代实验研究表明山栀子与水栀子化学成分组成、含量相似,具有相同的利胆作用。此外,系统整理了历代本草与方书中栀子的炮制方法和功效,并进行了分析,为栀子属资源的进一步研究与利用提供了参考和借鉴。 相似文献
3.
Sheng-Wei Wang Kuo-Hsien Hsu Shou-Chieh Huang Su-Hsiang Tseng Der-Yuan Wang Hwei-Fang Cheng 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(3):815-824
A gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) method is developed to determine 18 representative polycyclic aromatic hydrocarbons (PAHs) in cosmetics, including Benzo[a]pyrene (BaP) and others. The method offers high sensitivity and selectivity under selected reaction monitoring (SRM) mode to satisfy the requirements of both quantitation and qualitation. The extraction solvent system used in this study is acetone/hexane 1:1 (v/v) and other purification procedure is unnecessary. The linearities of 18 PAHs are validated in different concentration in the range of 0.25–20 ng/mL individually with coefficient correlation (r) higher than 0.996. The recoveries for spiking 3 different concentrations are from 87.40% to 120.44% for 18 PAHs and the coefficient of variation (CV) are below 12.32%. Limit of quantification (LOQ) of 18 PAHs is in the range of 0.05–0.2 mg/kg. A matrix enhancement effect is observed and can be compensated with deuterated internal standard. The method has been successfully applied to 73 samples, over 40 of them are lipsticks. The results show none of the samples detect Benzo[a]pyrene (BaP) and Dibenzo[a,h]anthracene (DBA), both are classified as the most carcinogenic. 8 PAHs are detected and the average value between 0.08 and 0.27 mg/kg. This study offers a sensitive and simple method to analyze 18 representative PAHs successfully and can be applied to cosmetic products and raw materials. 相似文献
4.
Benedita Sampaio-Maia Mónica Moreira-Rodrigues Paula Serr?o Manuel Pestana 《Nephrology, dialysis, transplantation》2006,21(2):314-323
BACKGROUND: A primary tubular sodium handling abnormality has been implicated in the edema formation of nephrotic syndrome. Dopamine synthesized by renal proximal tubules behaves as an endogenous natriuretic hormone by activating D(1)-like receptors as a paracrine/autocrine substance. METHODS: We examined the time courses of the urinary excretion of sodium, protein and dopamine in puromycin aminonucleoside (PAN)-treated and control rats. The rats were sacrificed during greatest sodium retention (day 7) as well as during negative sodium balance (day 14) for the evaluation of renal aromatic l-amino acid decarboxylase (AADC) activity, the enzyme responsible for the synthesis of renal dopamine. Also, the influence of volume expansion (VE) and the effects of the D(1)-like agonist fenoldopam (10 microg/kg bw/min) on natriuresis and on proximal tubular Na(+),K(+)-ATPase activity were examined on day 7. RESULTS: The daily urinary excretion of dopamine was decreased in PAN-treated rats, from day 5 and beyond. This was accompanied by a marked decrease in the renal AADC activity, on days 7 and 14. During VE, the fenoldopam-induced decrease in proximal tubular Na(+),K(+)-ATPase activity was more pronounced in PAN-treated rats than in controls. However, the urinary sodium excretion during fenoldopam infusion was markedly increased in control rats but was not altered in PAN-treated animals. CONCLUSION: PAN nephrosis is associated with a blunted renal dopaminergic system activity which may contribute to enhance the proximal tubular Na(+),K(+)-ATPase activity. However, the lack of renal dopamine appears not to be related with the overall renal sodium retention in a state of proteinuria. 相似文献
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中药透皮吸收促进剂具有起效快、效果好、副作用小、无污染等优点,总结近年来常用中药透皮吸收促进剂的研究进展,中药透皮吸收促进剂主要包括单一中药透皮吸收促进剂和含中药PE多元透皮吸收促进剂,并对存在的问题及今后的研究前景进行了思考和展望。 相似文献
7.
本文对煤焦沥青诱发大鼠肺癌过程中的病理形态学所见作了报道。整个过程可以分为三个阶段:1.异物反应阶段;2.异常增生和鳞状化生阶段;3.癌肿发生发展阶段。文中对每一个阶段的病理组织学改变做了详细描述。煤焦沥青诱发的大鼠肺癌的特征如下:1.癌肿全都发生在肺的周边部位;2.绝大多数癌肿的组织类型都是高分化鳞状细胞癌;3.多发性,数个至数十个大小不等的肿块布满全肺;4.癌变各个不同阶段的改变可在同一肺脏中出现;5.转移癌较少见。 相似文献
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10.
本文报告50名正常人及73例消化系疾病患者血清游离氨基酸检测结果。使用氨基酸自动分析仪,对血中40余种氨基酸组分进行定性定量测定。肝硬化病人芳香氨基酸显著升高,支/芳分子比值明显低于正常值(P<0.01),甲硫氨酸、色氨酸均升高.肝脓疡.消化道肿瘤患者也有此种变化(P<0.05)。统计21种组分中,各病理组有10多种组分有非常显著差异(P<0.01)。结果提示:血液氨基酸测定可为某些消化系疾患,尤其是肝病的诊治提供较好指标。本文改进自动分析条件,节省时间。节约试剂。 相似文献