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1.
Pulsed electromagnetic fields (PEMF) delivered by whole‐body mats are promoted in many countries for a wide range of therapeutic applications and for enhanced well‐being. However, neither the therapeutic efficacy nor the potential health hazards caused by these mats have been systematically evaluated. We conducted a systematic review of trials investigating the therapeutic effects of low‐frequency PEMF devices. We were interested in all health outcomes addressed so far in randomized, sham‐controlled, double‐blind trials. In total, 11 trials were identified. They were focused on osteoarthritis of the knee (3 trials) or the cervical spine (1), fibromyalgia (1), pain perception (2), skin ulcer healing (1), multiple sclerosis‐related fatigue (2), or heart rate variability and well‐being (1). The sample sizes of the trials ranged from 12 to 71 individuals. The observation period lasted 12 weeks at maximum, and the applied magnetic flux densities ranged from 3.4 to 200 µT. In some trials sporadic positive effects on health were observed. However, independent confirmation of such singular findings was lacking. We conclude that the scientific evidence for therapeutic effects of whole‐body PEMF devices is insufficient. Acute adverse effects have not been reported. However, adverse effects occurring after long‐term application have not been studied so far. In summary, the therapeutic use of low‐frequency whole‐body PEMF devices cannot be recommended without more scientific evidence from high‐quality, double‐blind trials. Bioelectromagnetics 33:95–105, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
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The potential effect of electromagnetic fields (EMFs) emitted from video display terminals (VDTs) to elicit biological response is a major concern for the public. The software professionals are subjected to cumulative EMFs in their occupational environments. This study was undertaken to evaluate DNA damage and incidences of micronuclei in such professionals. To the best of our knowledge, the present study is the first attempt to carry out cytogenetic investigations on assessing bioeffects in personal computer users. The study subjects (n = 138) included software professionals using VDTs for more than 2 years with age, gender, socioeconomic status matched controls (n = 151). DNA damage and frequency of micronuclei were evaluated using alkaline comet assay and cytochalasin blocked micronucleus assay respectively. Overall DNA damage and incidence of micronuclei showed no significant differences between the exposed and control subjects. With exposure characteristics, such as total duration (years) and frequency of use (minutes/day) sub-groups were assessed for such parameters. Although cumulative frequency of use showed no significant changes in the DNA integrity of the classified sub-groups, the long-term users (> 10 years) showed higher induction of DNA damage and increased frequency of micronuclei and micro nucleated cells. 相似文献
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《Saudi Journal of Biological Sciences》2020,27(6):1566-1568
A total of 108 blood samples obtained from 28 male and 80 female patients diagnosed with ME were diluted in sterile, Ringer’s Solution and forced (by suction) through 0.2 µm filters. Of the 28 male samples, 4 yielded filterable bacteria and of the 80 female samples, 18 gave filterable bacteria; as a result, of the total of 124 samples, 22 yielded FB. Filterable (0.4 and 0.2, but not 0.1micron filterable) bacteria were also isolated from the nose throat and skin of paediatric patients and from the throat and skin of staff at an emergency paediatric hospital. The highest percentage of bacterial passage occurred through the largest (0.4 µm) pores. The results show that ultrasmall bacteria occur in ME patients and in paediatric patients and nurses. The potential pathogenic role of such filterable bacteria is briefly discussed. 相似文献
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《Biomarkers》2013,18(6):530-535
Context: In management of community-acquired pneumonia (CAP), excellent biomarkers for inflammation would be helpful in our practice.Objectives: Kinetics of c-reactive protein (CRP) and serum amyloid A (SAA) was characterized, using their biologic half-life times.Materials and methods: Time course of CRP and SAA levels in the successfully treated 36 CAP patients were investigated and their half-life times were determined and compared.Results & Discussions: SAA and CRP declined in an exponential mean and the biologic half-life times of SAA levels was 34.9?±?28.7?h, significantly shorter than that of CRP, 46.4?±?21.7?h (p?=?0.0014). Conclusion: The kinetic evidence, presented as biologic half-life times of CRP and SAA, helps us make a clinical assessment of CAP patients. 相似文献
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Ultrasound‐assisted three‐phase partitioning of polyphenol oxidase from potato peel (Solanum tuberosum) 下载免费PDF全文
Conventional three phase partitioning (TPP) and ultrasound assisted three phase partitioning (UATPP) were optimized for achieving the maximum extraction and purification of polyphenol oxidase ( PPO) from waste potato peels. Different process parameters such as ammonium sulfate (NH4)2SO4 concentration, crude extract to t‐butanol ratio, time, temperature and pH were studied for conventional TPP. Except agitation speed, the similar parameters were also optimized for UATPP. Further additional parameters were also studied for UATPP viz. irradiation time at different frequencies, duty cycle and, rated power in order to obtain the maximum purification factor and recovery of PPO. The optimized conditions for conventional TPP were (NH4)2SO4 0‐40% (w/v), extract to t‐butanol ratio 1:1 (v/v), time 40 min and pH 7 at 30°C. These conditions provided 6.3 purification factor and 70% recovery of PPO from bottom phase. On the other hand, UATPP gives maximum purification fold of 19.7 with 98.3% recovery under optimized parameters which includes (NH4)2SO4 0‐40% (w/v), crude extract to t‐butanol ratio 1: 1 (v/v) pH 7, irradiation time 5 min with 25 kHz, duty cycle 40% and rated power 150W at 30°C. UATPP delivers higher purification factor and % recovery of PPO along with reduced operation time from 40 min to 5 min when compared with TPP. SDS PAGE showed partial purification of PPO enzyme with UATPP with molecular weight in the range of 26‐36 kDa. Results reveal that UATPP would be an attractive option for the isolation and purification of PPO without need of multiple steps. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1340–1347, 2015 相似文献
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为了探讨齐口裂腹鱼(Schizothorax prenanti)血细胞发生发育的模式,采用Wright’s、碘酸雪夫氏(PAS)和苏丹黑B(SBB)染色方法对齐口裂腹鱼的头肾、中肾、脾和肝组织印片进行染色,了解其发生的具体组织和发育的一般过程。结果表明:齐口裂腹鱼血细胞可分为红细胞系、淋巴细胞系、单核细胞系、粒细胞系和其他细胞,且这些细胞系的发育均经过3个阶段,即原始阶段、幼稚阶段、成熟阶段。通过观察和统计不同阶段各种血细胞的形态、大小、比例及染色特征,发现原始阶段的血细胞体积较大,其中原始单核细胞最大,大小为(18.90±1.59)μm×(16.32±0.70)μm,在4种组织中原始阶段的红细胞和单核细胞在头肾中所占比例最大,分别为0.64%和0.59%,原粒细胞和原淋巴细胞分别在中肾和脾中比例最大,在肝中少量存在,此外在各组织印片中均发现血栓细胞的存在,在肝中发现巨噬细胞。因此头肾、中肾和脾是齐口裂腹鱼的主要造血组织,少量细胞在肝中产生。粒细胞发育过程中,除原始粒细胞PAS染色阴性外,其他阶段均呈阳性,且阳性随不断成熟逐渐增强;单核细胞从原单核细胞到成熟的单核细胞,PAS阳性逐渐增强;而SBB染色发现,粒细胞、淋巴细胞及单核细胞均呈阳性,未成熟的细胞染色程度不一致,成熟的细胞阳性染色最为强烈。在红细胞系发育过程中经历了细胞由大变小再变大的过程,而粒细胞和淋巴细胞发育过程仅出现由大变小的过程,在红细胞的发育过程中还出现了染色质固缩和血红蛋白增加。 相似文献
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目的:探讨强心益气方联合瑞舒伐他汀治疗急性心肌梗死的临床疗效及对患者白细胞计数(WBC)、中性粒细胞比值(NEU)、肌红蛋白及C反应蛋白(CRP)水平的影响。方法:选自2014年6月~2015年12月我院收治的急性心肌梗死患者96例,随机分为观察组与对照组,每组48例。对照组采用瑞舒伐他汀治疗,观察组在对照组基础上给予强心益气方治疗。观察并比较两组患者的治疗疗效以及治疗前后心功能指标、WBC、NEU、肌红蛋白、CRP水平变化,及用药期间不良反应情况。结果:观察组治疗总有效率(89.58%)高于对照组(70.83%)(P0.05);与治疗前比较,两组LVEF、SV治疗后明显升高,而LVEDV明显降低(P0.05);观察组LVEF、SV治疗后高于对照组,而LVEDV低于对照组(P0.05);与治疗前比较,两组WBC、NEU、肌红蛋白、CRP水平治疗后明显降低(P0.05);观察组WBC、NEU、肌红蛋白、CRP水平治疗后低于对照组(P0.05);两组均未见严重不良反应。结论:强心益气方联合瑞舒伐他汀治疗急性心肌梗死患者疗效显著,可降低WBC、NEU、肌红蛋白、CRP含量,安全可靠,值得研究。 相似文献
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Zhiwei Niu Yue Hu Zhili Chu Meng Yu Yaofu Bai Long Wang Jinlian Hua 《Cell biochemistry and function》2013,31(1):12-19
Historically, our understanding of molecular genetic aspects of germ cell development has been limited. Recently, results demonstrated that the derivation of pluripotent stem cells may provide the necessary genetic system to study germ cell development. Here, we characterized an induced pluripotent stem cell (iPSC) line, which can spontaneously differentiate into embryonic bodies (EBs) after 3 days of suspension culture, expressing specific markers of three germ layers. Then, we induced the iPSCs to differentiate into germ cells by culturing adherent EBs in retinoic acid (RA) and porcine follicular fluid (PFF) differentiation medium or seminiferous tubule transplantation. Our results indicated that RA and PFF were beneficial for the derivation of germ cells and oocyte‐like cells from iPSCs, and iPSCs transplantation could make a contribution to repairing the testis of infertile mice. Our study offers an approach for further study on the development and the differentiation of germ cells derived from iPSCs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Dorothee Dormann Ramona Rodde Dieter Edbauer Eva Bentmann Ingeborg Fischer Alexander Hruscha Manuel E Than Ian R A Mackenzie Anja Capell Bettina Schmid Manuela Neumann Christian Haass 《The EMBO journal》2010,29(16):2841-2857
Mutations in fused in sarcoma (FUS) are a cause of familial amyotrophic lateral sclerosis (fALS). Patients carrying point mutations in the C‐terminus of FUS show neuronal cytoplasmic FUS‐positive inclusions, whereas in healthy controls, FUS is predominantly nuclear. Cytoplasmic FUS inclusions have also been identified in a subset of frontotemporal lobar degeneration (FTLD‐FUS). We show that a non‐classical PY nuclear localization signal (NLS) in the C‐terminus of FUS is necessary for nuclear import. The majority of fALS‐associated mutations occur within the NLS and impair nuclear import to a degree that correlates with the age of disease onset. This presents the first case of disease‐causing mutations within a PY‐NLS. Nuclear import of FUS is dependent on Transportin, and interference with this transport pathway leads to cytoplasmic redistribution and recruitment of FUS into stress granules. Moreover, proteins known to be stress granule markers co‐deposit with inclusions in fALS and FTLD‐FUS patients, implicating stress granule formation in the pathogenesis of these diseases. We propose that two pathological hits, namely nuclear import defects and cellular stress, are involved in the pathogenesis of FUS‐opathies. 相似文献
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Circulating miR‐145 is associated with plasma high‐sensitivity C‐reactive protein in acute ischemic stroke patients 下载免费PDF全文
Stroke is a major cerebrovascular disease threatening human health and life with high morbidity, disability and mortality. We aimed to find effective biomarkers for the early diagnosis on stroke. Nine previously reported stroke‐associated miRNAs (miR‐21, miR‐23a, miR‐29b, miR‐124, miR‐145, miR‐210, miR‐221, miR‐223 and miR‐483‐5p) were measured by quantitative real time‐PCR, and plasma high‐sensitivity C‐reactive protein (hs‐CRP) and serum interleukin 6 (IL‐6), the pro‐inflammation markers in brain injury, were examined by enzyme‐linked immunosorbent assay in 146 acute ischemic stroke patients and 96 healthy blood donors. We found that serum miR‐145 was significantly increased within 24 h after stroke onset and serum miR‐23a and miR‐221 were decreased in patients. Moreover, serum miR‐145 was strong positively correlated with plasma hs‐CRP and moderate positively correlated with serum IL‐6. Meanwhile, serum miR‐23a and miR‐221 were moderate negatively correlated with plasma hs‐CRP but not serum IL‐6. Importantly, the combination of hs‐CRP and serum miR‐145 gained a better sensitivity/spectivity for prediction of acute ischemia stroke (area under receiver operating characteristic curve from 0.794 to 0.896). Conclusively, our preliminary findings indicate that serum miR‐145 upregulated in acute ischemic stroke might be a new biomarker for acute ischemia stroke evaluation. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Within two years of the re‐discovery of Mendelism, Bateson and Saunders had described six traits in non‐laboratory animals (five in chickens and one in cattle) that show single‐locus (Mendelian) inheritance. In the ensuing decades, much progress was made in documenting an ever‐increasing number of such traits. In 1987 came the first discovery of a causal mutation for a Mendelian trait in non‐laboratory animals: a non‐sense mutation in the thyroglobulin gene (TG), causing familial goitre in cattle. In the years that followed, the rate of discovery of causal mutations increased, aided mightily by the creation of genome‐wide microsatellite maps in the 1990s and even more mightily by genome assemblies and single‐nucleotide polymorphism (SNP) chips in the 2000s. With sequencing costs decreasing rapidly, by 2012 causal mutations were being discovered in non‐laboratory animals at a rate of more than one per week. By the end of 2012, the total number of Mendelian traits in non‐laboratory animals with known causal mutations had reached 499, which was half the number of published single‐locus (Mendelian) traits in those species. The distribution of types of mutations documented in non‐laboratory animals is fairly similar to that in humans, with almost half being missense or non‐sense mutations. The ratio of missense to non‐sense mutations in non‐laboratory animals to the end of 2012 was 193:78. The fraction of non‐sense mutations (78/271 = 0.29) was not very different from the fraction of non‐stop codons that are just one base substitution away from a stop codon (21/61 = 0.34). 相似文献
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Wout Joseph Patrizia Frei Martin Röösli Günter Vermeeren John Bolte György Thuróczy Peter Gajšek Tomaž Trček Evelyn Mohler Péter Juhász Viktoria Finta Luc Martens 《Bioelectromagnetics》2012,33(8):682-694
In five countries (Belgium, Switzerland, Slovenia, Hungary, and the Netherlands), personal radio frequency electromagnetic field measurements were performed in different microenvironments such as homes, public transports, or outdoors using the same exposure meters. From the mean personal field exposure levels (excluding mobile phone exposure), whole‐body absorption values in a 1‐year‐old child and adult male model were calculated using a statistical multipath exposure method and compared for the five countries. All mean absorptions (maximal total absorption of 3.4 µW/kg for the child and 1.8 µW/kg for the adult) were well below the International Commission on Non‐Ionizing Radiation Protection (ICNIRP) basic restriction of 0.08 W/kg for the general public. Generally, incident field exposure levels were well correlated with whole‐body absorptions (SARwb), although the type of microenvironment, frequency of the signals, and dimensions of the considered phantom modify the relationship between these exposure measures. Exposure to the television and Digital Audio Broadcasting band caused relatively higher SARwb values (up to 65%) for the 1‐year‐old child than signals at higher frequencies due to the body size‐dependent absorption rates. Frequency Modulation (FM) caused relatively higher absorptions (up to 80%) in the adult male. Bioelectromagnetics 33:682–694, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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Induction of systemic disease resistance in Nicotiana benthamiana by the cyclodipeptides cyclo (l‐Pro‐l‐Pro) and cyclo (d‐Pro‐d‐Pro) 下载免费PDF全文
Cyclodipeptides, formed from two amino acids by cyclodehydration, are produced naturally by many organisms, and are known to possess a large number of biological activities. In this study, we found that cyclo (l ‐Pro‐l ‐Pro) and cyclo (d ‐Pro‐d ‐Pro) (where Pro is proline) could induce defence responses and systemic resistance in Nicotiana benthamiana. Treatment with the two cyclodipeptides led to a reduction in disease severity by Phytophthora nicotianae and Tobacco mosaic virus (TMV) infections compared with controls. Both cyclopeptides triggered stomatal closure, induced reactive oxygen species production and stimulated cytosolic calcium ion and nitric oxide production in guard cells. In addition, the application of cyclodipeptides significantly up‐regulated the expression of the plant defence gene PR‐1a and the PR‐1a protein, and increased cellular salicylic acid (SA) levels. These results suggest that the SA‐dependent defence pathway is involved in cyclodipeptide‐mediated pathogen resistance in N. benthamiana. We report the systemic resistance induced by cyclodipeptides, which sheds light on the potential of cyclodipeptides for the control of plant diseases. 相似文献
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Colonization and maintenance of mosquitoes in the laboratory is required to study physiology, ecology, and behavior of mosquitoes and interactions between mosquito and pathogens. Artificial blood feeding systems have been widely used to maintain the laboratory colony of Aedes albopictus. In this study, we investigated the effects of mating period (1, 3, 6, and 10 days) and time‐of‐day for bloodmeal (08:00, 13:00, and 18:00) in the use of an artificial feeding system on blood‐feeding rate, female fecundity, egg hatching rate, and developmental time of the Asian tiger mosquito, A. albopictus. Younger females mated for three or fewer days reproduced more eggs compared to those of oldest females mated for ten days. Similar to the result for eggs laid, the mean egg‐hatching rate was significantly higher from the offspring of younger females than from those of older females. However, mating period and time‐of‐day for bloodmeal had no effect on the blood feeding rate and developmental time. Taken together, we suggest that three‐day mating with bloodmeal at 18:00 is optimal for maintaining colonies of A. albopictus in laboratory conditions. 相似文献
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M. O. Duarte C. Mendes‐Rodrigues M. F. Alves P. E. Oliveira D. S. Sampaio 《Plant biology (Stuttgart, Germany)》2017,19(2):140-146
- Mixed cross and self‐pollen load on the stigma (mixed pollination) of species with late‐acting self‐incompatibility system (LSI) can lead to self‐fertilized seed production. This “cryptic self‐fertility” may allow selfed seedling development in species otherwise largely self‐sterile. Our aims were to check if mixed pollinations would lead to fruit set in LSI Adenocalymma peregrinum, and test for evidence of early‐acting inbreeding depression in putative selfed seeds from mixed pollinations.
- Experimental pollinations were carried out in a natural population. Fruit and seed set from self‐, cross and mixed pollinations were analysed. Further germination tests were carried out for the seeds obtained from treatments.
- Our results confirm self‐incompatibility, and fruit set from cross‐pollinations was three‐fold that from mixed pollinations. This low fruit set in mixed pollinations is most likely due to a greater number of self‐ than cross‐fertilized ovules, which promotes LSI action and pistil abortion. Likewise, higher percentage of empty seeds in surviving fruits from mixed pollinations compared with cross‐pollinations is probably due to ovule discounting caused by self‐fertilization. Moreover, germinability of seeds with developed embryos was lower in fruits from mixed than from cross‐pollinations, and the non‐viable seeds from mixed pollinations showed one‐third of the mass of those from cross‐pollinations.
- The great number of empty seeds, lower germinability, lower mass of non‐viable seeds, and higher variation in seed mass distribution in mixed pollinations, strongly suggests early‐acing inbreeding depression in putative selfed seeds. In this sense, LSI and inbreeding depression acting together probably constrain self‐fertilized seedling establishment in A. peregrinum.
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Rapid molecular methods for in‐field and laboratory identification of the yellow‐legged Asian hornet (Vespa velutina nigrithorax) 下载免费PDF全文
K. Stainton J. Hall G. E. Budge N. Boonham J. Hodgetts 《Journal of Applied Entomology》2018,142(6):610-616
The yellow‐legged Asian hornet (Vespa velutina nigrithorax) is an invasive species that presents a threat to apiculture in Europe; first introduced into France in 2004, it has subsequently spread into neighbouring European countries. There is a risk of invasion and establishment in the UK, and in 2016, nests were found and destroyed in Alderney in the Channel Islands, and in Tetbury, Gloucestershire, illustrating a need for screening of suspect specimens so that invading hornets can be rapidly identified, and their nests destroyed. In this study, loop‐mediated isothermal amplification (LAMP) and real‐time PCR assays were developed to enable both in‐field and laboratory testing. Species‐specific identification assays and generic invertebrate control assays were developed. All the assays were validated according to the European Plant Protection Organisation standard PM 7/98. The assays were tested successfully against V. velutina nigrithorax obtained from France, Asia and the UK. Eight non‐target species, that were closely related or morphologically similar to the Asian hornet, gave negative results with the species‐specific assays, and positive results with the control assays. The assays could be used to detect target DNA at concentrations as low as 5 pg per reaction. LAMP was rapid, and cable of generating positive results within 10 min. Using simplified sample homogenization protocols that could be performed in the field, the LAMP assay was successful when tested against all developmental stages and nest samples, assisting with identification of samples that cannot be determined morphologically and allowing detection away from the laboratory. These assays provide a valuable tool for fast and reliable detection of this invasive species, offering the ability to identify damaged/incomplete specimens and immature life‐stages. 相似文献
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Sebastian L. Riedel Christopher J. Brigham Charles F. Budde Johannes Bader ChoKyun Rha Ulf Stahl Anthony J. Sinskey 《Biotechnology and bioengineering》2013,110(2):461-470
Reduced downstream costs, together with high purity recovery of polyhydroxyalkanoate (PHA), will accelerate the commercialization of high quality PHA‐based products. In this work, a process was designed for effective recovery of the copolymer poly(hydroxybutyrate‐co‐hydroxyhexanoate) (P(HB‐co‐HHx)) containing high levels of HHx (>15 mol%) from Ralstonia eutropha biomass using non‐halogenated solvents. Several non‐halogenated solvents (methyl isobutyl ketone, methyl ethyl ketone, and butyl acetate and ethyl acetate) were found to effectively dissolve the polymer. Isoamyl alcohol was found to be not suitable for extraction of polymer. All PHA extractions were performed from both dry and wet cells at volumes ranging from 2 mL to 3 L using a PHA to solvent ratio of 2% (w/v). Ethyl acetate showed both high recovery levels and high product purities (up to 99%) when using dry cells as starting material. Recovery from wet cells, however, eliminates a biomass drying step during the downstream process, potentially saving time and cost. When wet cells were used, methyl isobutyl ketone (MIBK) was shown to be the most favorable solvent for PHA recovery. Purities of up to 99% and total recovery yields of up to 84% from wet cells were reached. During polymer recovery with either MIBK or butyl acetate, fractionation of the extracted PHA occurred, based on the HHx content of the polymer. PHA with higher HHx content (17–30 mol%) remained completely in solution, while polymer with a lower HHx content (11–16 mol%) formed a gel‐like phase. All PHA in solution could be precipitated by addition of threefold volumes of n‐hexane or n‐heptane to unfiltered PHA solutions. Effective recycling of the solvents in this system is predicted due to the large differences in the boiling points between solvent and precipitant. Our findings show that two non‐halogenated solvents are good candidates to replace halogenated solvents like chloroform for recovery of high quality PHA. Biotechnol. Bioeng. 2013; 110: 461–470. © 2012 Wiley Periodicals, Inc. 相似文献