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41.
Despite consumer and regulatory focus on the quality of final food and beverage (F&B) products, little attention is given to the release and management of toxic chemicals by F&B processors. This study develops five plant-level indicators of environmental performance specific to toxic chemicals. Our findings suggest that (i) only few F&B processors invest in toxic chemical prevention activities; (ii) the major toxic chemical management strategy is treatment rather than recycling or energy recovery; (iii) F&B processors, on average, have improved their toxic chemical management rates between 2001 and 2012; and (iv) there is evidence for homogeneous performance across similar producers in the F&B processing industry but there is no evidence for the role of socio-economic characteristics of surrounding communities on the environmental performance of F&B processors. 相似文献
42.
Kissner TL Moisan L Mann E Alam S Ruthel G Ulrich RG Rebek M Rebek J Saikh KU 《The Journal of biological chemistry》2011,286(36):31385-31396
43.
Plant growth promoting rhizobacteria and endophytes accelerate phytoremediation of metalliferous soils 总被引:8,自引:0,他引:8
Technogenic activities (industrial—plastic, textiles, microelectronics, wood preservatives; mining—mine refuse, tailings, smelting; agrochemicals—chemical fertilizers, farm yard manure, pesticides; aerosols—pyrometallurgical and automobile exhausts; biosolids—sewage sludge, domestic waste; fly ash—coal combustion products) are the primary sources of heavy metal contamination and pollution in the environment in addition to geogenic sources. During the last two decades, bioremediation has emerged as a potential tool to clean up the metal-contaminated/polluted environment. Exclusively derived processes by plants alone (phytoremediation) are time-consuming. Further, high levels of pollutants pose toxicity to the remediating plants. This situation could be ameliorated and accelerated by exploring the partnership of plant-microbe, which would improve the plant growth by facilitating the sequestration of toxic heavy metals. Plants can bioconcentrate (phytoextraction) as well as bioimmobilize or inactivate (phytostabilization) toxic heavy metals through in situ rhizospheric processes. The mobility and bioavailability of heavy metal in the soil, particularly at the rhizosphere where root uptake or exclusion takes place, are critical factors that affect phytoextraction and phytostabilization. Developing new methods for either enhancing (phytoextraction) or reducing the bioavailability of metal contaminants in the rhizosphere (phytostabilization) as well as improving plant establishment, growth, and health could significantly speed up the process of bioremediation techniques. In this review, we have highlighted the role of plant growth promoting rhizo- and/or endophytic bacteria in accelerating phytoremediation derived benefits in extensive tables and elaborate schematic sketches. 相似文献
44.
中国植物内生微生物研究的发展和展望 总被引:7,自引:0,他引:7
我国植物内生微生物的早期研究论文,基本上以非豆科植物根瘤菌Frankia属细菌为主。进入21世纪后,植物内生菌的研究,无论是研究领域的扩大,研究人员的增加,还是论文数量的递增都有了迅猛的发展,为国际上少有。我国植物内生微生物的研究具有资源探索多、分离培养多、活性检测多、活性物质功能研究多;方法研究少、涉及林木少、与宿主的关联少、实际应用少等特点。其研究主要集中在红豆杉类、红树类、鬼臼类、兰、银杏等植物中的内生微生物。论文的发表以药物开发为研究目标的最多,又以初级的资源探索型为最。以抗菌、抗肿瘤等指标为主的药物开发,是植物内生微生物研究中最耀眼的亮点,目前已获得了紫杉醇生产效率较高的内生真菌菌株资源。我国植物内生微生物研究有4大类24个应用研究的方向,其中特别值得关注的是豆科植物根瘤内生细菌的研究;尚待加强的有6个方面,尤其是深色有隔内生真菌(DSE)的研究。我国植物内生微生物研究在药用植物内生微生物的资源探索和筛选方面积累较丰富,而在有害内生微生物方面的研究则比较薄弱。最后,作者提示了一些尚待加强的研究技术,供相关人员参考。 相似文献
45.
《Journal of trace elements in medicine and biology》2014,28(3):317-321
Nowadays several papers deal with the effectiveness and side effects of metal complexes, especially cisplatin, in cancer therapy. The excretion of essential metal elements from the body is a serious problem in the treatment, but there are no data concerning the distribution and metabolism of toxic and nonessential elements. Therefore our aim was to study the concentration of some of these elements after treatment with cisplatin. Male Wistar rats (n = 20, 175–190 g) were randomly divided into 2 groups (n = 10/group). The control group received 1% (w/v) methyl cellulose at 10 mL/kg body weight, p.o. by gastric gavage twice daily for 14 days, while cisplatin was injected i.p. in a single dose of 6.5 mg/kg body weight. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used for measuring Al, B, Ba, Cr, Li, Ni, Pb, Pt, Sb, Si, Sn, Sr and V content in plasma, liver and kidney. Liver total scavenger capacity, diene conjugate content and malondialdehyde concentration were also determined. Cisplatin elevated the free radical reactions in the liver, although redox balance did not change significantly. According to the study it seems that the metabolism of Al, Ba, Cr, Ni, Pb, Sr were changed by the effect of cisplatin, and the most notable alterations were found for Al and Pb. Therefore, besides the toxic effect of and free radical induction by Pt, the side effects of increased levels of other toxic and non-essential elements have to be taken into consideration. 相似文献
46.
目的:探讨SOX方案与FOLFOX4治疗进展期胃癌的临床疗效、毒副作用及生存时间。方法:选取2013年10月到2014年10月期间唐山市人民医院收治的进展期胃癌患者90例作为研究对象,根据随机数字表法将其分为SOX组与FOLFOX4组,两组均为45例。SOX组患者给予奥沙利铂+替吉奥胶囊进行治疗,FOLFOX4组给予奥沙利铂+亚叶酸钙+氟尿嘧啶进行治疗。比较两组患者的疾病缓解率、疾病控制率、毒副反应、1年生存率、2年生存率和3年生存率。结果:两组患者的的疾病缓解率和疾病控制率经统计分析差异均无统计学意义(P0.05)。两组患者红细胞下降、血小板下降、腹泻、外周神经症状、手足综合征、肝功能异常发生率比较差异均无统计学意义(P0.05),FOLFOX4组I-II级白细胞下降、恶心呕吐的发生率高于SOX组(P0.05),两组III-IV级白细胞下降、恶心呕吐的发生率比较差异无统计学意义(P0.05)。两组患者的1年生存率、2年生存率、3年生存率经统计分析差异均无统计学意义(P0.05)。结论:SOX方案与FOLFOX4治疗进展期胃癌的临床疗效相近,且患者的生存时间无明显差异,但SOX方案的白细胞下降、恶心呕吐等毒副反应程度较轻。 相似文献
47.
IntroductionEnvironmental pollution, especially by toxic trace elements, is a global health concern. Heavy metals such as Cadmium (Cd), Arsenic (As) and Lead (Pb) are associated with numerous disorders and are considered by some as an aetiological factor for the Chronic Kidney Disease (CKDu1) epidemic in Sri Lanka. This study explores patterns of bioaccumulation of six trace elements in kidneys obtained during forensic autopsies from urban and rural regions in Sri Lanka.MethodsKidney samples obtained from one urban district (n = 13) and three rural districts (n = 18) were lyophilized, microwave digested and profiled by ICP-MS techniques.Results and DiscussionThe mean age of the sampled population was 47.9 ± 11.3 yrs. Median (IQR) for Cd, As, Pb, Cr, Zn and Se were, 14.67(8.04–22.47) μg/g, 0.44(0.29–0.56) μg/g, 0.11(0.07–0.30) μg/g, 0.15(0.1096–0.3274), 25.55(17.24–39.35) μg/g and 0.52(0.37−0.84) μg/g, respectively. Cd, Zn and Se levels were significantly higher (p < 0.05) among the urban samples compared to that of the rural group. Zn and Se levels were higher among younger age groups. As, Pb and Cr did not show any significant differences between the two cohorts nor any correlations with age.ConclusionThis population-specific baseline study provides an insight into the differences in exposure to toxic trace elements and essential elements between urban and rural populations. Residents in CKDu affected rural districts did not appear to be at risk of toxic heavy metal exposure, however their renal bioaccumulation of nephroprotective essential elements was lower than urban residents. 相似文献
48.
目的:探讨吉西他滨热化疗治疗肝癌的临床效果及对血清O6-甲基鸟嘌呤DNA甲基转移酶(O6-methylguanine-DNA methyltransferase,MGMT)水平的影响。方法:选取2014年2月-2017年4月在我院诊治的59例肝癌患者,根据治疗方法的方法不同分为观察组30例、对照组29例,对照组给予常规化疗,化疗观察3个周期;观察组在对照组化疗的基础上给予吉西他滨热灌注化疗,比较两组的临床疗效、不良反应的发生情况、生存情况及治疗前后血清MGMT表达的变化情况。结果:观察组患者的热灌注化疗均成功进行,治疗前后患者的体温、呼吸频率、心率、血压等对比无显著差异(P0.05)。治疗后,观察组总有效率是66.7%,显著高于对照组(31.0%)(P0.05)。两组治疗期间的毒性反应发生率间无显著差异(P0.05)。两组治疗后血清MGMT表达都较治疗前显著降低(P0.05),且观察组的血清MGMT表达明显比对照组低(P0.05)。随访至2017年11月30日,观察组的疾病进展时间(Time to Progression,TTP)、生存时间(overall survival,OS)分别为8.11±2.19个月和14.29±1.87个月,都显著高于对照组的6.22±1.82个月和11.48±2.19个月(P0.05)。结论:吉西他滨热化疗治疗肝癌可提高疗效,延长患者的生存时间,且不增加毒副反应,可能与其有效降低患者血清MGMT表达有关。 相似文献
49.
50.
John W. M. Martens Bert Visser Just M. Vlak Dirk Bosch 《Molecular & general genetics : MGG》1995,247(4):482-487
The amino acid sequences necessary for entomocidal activity of the CryIA(b) protoxin of Bacillus thuringiensis were determined. Introduction of stop codons behind codons Arg601, Phe604 or Ala607 showed that amino acid residues C-terminal to Ala607 are not required for insecticidal activity and that activation by midgut proteases takes place distal to Ala607. The two shortest polypeptides, deleted for part of the highly conserved -strand, were prone to proteolytic degradation, explaining their lack of toxicity. Apparently, this -strand is essential for folding of the molecule into a stable conformation. Proteolytic activation at the N-terminus was investigated by removing the first 28 codons, resulting in a translation product extending from amino acid 29 to 607. This protein appeared to be toxic not only to susceptible insect larvae such as Manduca sexta and Heliothis virescens, but also to Escherichia coli cells. An additional mutant, encoding only amino acid residues 29–429, encompassing the complete putative pore forming domain, but lacking a large part of the receptor-binding domain, was similarly toxic to E. coli cells. This suggests a role for the N-terminal 28 amino acids in rendering the toxin inactive in Bacillus thuringiensis, and indicates that the cytolytic potential of the pore forming domain is only realized after proteolytic removal of these residues by proteases in the insect gut. In line with this hypothesis are results obtained with a mutant protein in which Arg28 at the cleavage site was replaced by Asp. This substitution prevented the protein from being cleaved by trypsin in vitro, and reduced its toxicity to M. sexta larvae. 相似文献