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Journal of Environmental Sciences 2004年第5期16卷 751-754页

作者： m. Radzi Bin Abas Nasr Yousef m. J. Omar m. Jamil maah Department of Chemistry University of Malaya 50603 Kuala Lumpur MalaysiaDepartment of Chemistry University of Malaya 50603 Kuala Lumpur MalaysiaDepartment of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia

Pm 10 airborne particles and soot deposit collected after a fire incident at a chemical store were analyzed in order to determine the concentrations of polycyclic aromatic hydrocarbons(PAHs). The samples were extracted with 1∶1 hexane-dichloromethane by ultrasonic agitation. The extracts were then subjected to gas chromatography-mass spectrometric(GC-mS) analysis. The total PAHs concentrations in airborne particles and soot deposit were found to be 3.27±1.55 ng/m 3 and 12.81±24.37 μg/g, respectively. Based on the molecular distributions of PAHs and the interpretation of their diagnostic ratios such as PHEN/(PHEN + ANTH), fLT/(fLT + PYR) and BeP/(BeP + BaP), PAHs in both airborne particles and soot deposit may be inferred to be from the same source. The difference in the value of IP/(IP + BgP) for these samples indicated that benzo[g,h,i]perylene and coronene tend to be attached to finer particles and reside in the air for longer periods. Comparison between the molecular distributions of PAHs and their diagnostic ratios observed in the current study with those reported for urban atmospheric and roadside soil particles revealed that they are of different sources.

关键词： airborne particles soot deposit PAHs

Stereological study of the effects of vitamin E on testis structure in rats treated with para-nonylphenol

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Asian Journal of Andrology 2009年第4期11卷 508-516页

作者： m Soleimani mehranjani A Noorafshan HR momeni mH Abnosi m mahmoodi m Anvari Sm Hoseini Biology Department Arak University Arak 38156 Iran Anatomy Department Shiraz University of Medical Sciences Shiraz 71348 Iran Anatomy Department Research and Clinical Center for Infertility Shahid Sadoughi University of Medical Sciences Yazd 89195-999 Iran

This study was organized to see whether vitamin E, as a strong antioxidant, could affect the abnormalities of testis structure caused by para-nonylphenol （p-NP） during its development. A total of 32 female Wistar rats after mating were divided into four groups （n = 8）： control, vitamin E （100 mg kg^-1 per day）, p-NP （250 mg kg^-1 per day） and p-NP ＋ vitamin E. The rats were treated from the seventh day of pregnancy till the twenty-first day. After weaning, the male pups were divided into the same groups and were treated orally for 90 days. finally, the right testis was fixed, processed, stained and studied using stereological methods. The weight and volume of testis, volume of seminiferous tubules and its diameter, thickness of the basement membrane, height of the germinal epithelium, total number of types A and B spermatogonia, spermatocyte, spermatid and Sertoli cells were significantly reduced in p-NP group when compared with other groups. Co-administration of vitamin E and p-NP compensated for the adverse effects of p-NP on the above parameters. In addition, treatment with only vitamin E caused a significant increase in diameter, basement membrane thickness and height of germinal epithelium, number of spermatogonia and spermatocytes. Co-administration of vitamin E with p-NP could prevent the adverse effects ofp-NP on the testis structure during its development.

关键词： development para-nonylphenol stereology testis vitamin E

Improved maceration techniques to study the fruit vascular anatomy of grape

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Horticultural Plant Journal 2023年第3期9卷 481-495页

作者： Zhaosen Xie Teng fei Charles f.forney Youmei Li Bo Li College of Horticulture and Plant Protection Yangzhou UniversityYangzhouJiangsu225009China Kentville Research and Development Centre Agriculture and Agri-Food CanadaKentvilleNova ScotiaB4N 1J5Canada Shandong Academy of Grape JinanShandong 250199China

The visualization and evaluation of fruit vascular bundles in grape are indispensable for understanding the development and growth of the fruit. The vascular bundles in grape are as thin as human hair, and strongly adhere to flesh cells, making it difficult to isolate individual intact vessel elements. Currently there is little information about methods to characterize grape vascular tissue. In this study, we describe an easy and effective technique to visualize the xylem cell structure of the ‘Red Globe' grape(Vitis L.). The intact vascular bundles of the grape were isolated through enzymatic degradation of flesh cells by hydrolases which were effective in removing flesh cells from vascular bundles. This enabled the illustration of the fine surface structure of vessel elements and their arrangement in the vascular bundles of the grape. This modified method to separate the vascular bundles into individual vessel elements was more effective than former methods of manually shaking to isolate individual vessels. Clear images of xylem vessel arrangement and structural characteristics of individual vessel element were acquired by light microscopy(BX51, Olympus, Tokyo, Japan), transmission electron microscopy(Tecnai 12, Philips, Netherlands) and scanning electron microscopy(GeminiSEm 300, Carl Zeiss, Germany). In addition, the 3D structure of vessel elements was observed using confocal laser scanning microscopy(Zeiss: model: LSm-880, Oberkochen, Germany). The imaging techniques for visualizing and analyzing the structure of xylem vessels in grape described in this study are an improvement of past methods. An effective method to isolate grape vascular bundles from flesh cells was also developed, which enables the imaging of the fine surface structure of vessel elements and their arrangement in grape vascular bundles. By adjusting the process of maceration of vascular bundles, an easy and effective method was developed to gently disrupt the plant tissue and isolate individu

关键词： Grape fruit Vascular bundle Vessel element maceration Anatomy

Rat cardiomyocyte H9c2(2-1)-based sulforhodamine B assay as a promising in vitro method to assess the biological component of effluent toxicity

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Journal of Environmental Sciences 2020年第10期32卷 163-170页

作者： Elsa T Rodrigues Susana f Nascimento maria Joao moreno Paulo J Oliveira miguel A Pardal University of Coimbra Centre for Functional EcologyDepartment of Life SciencesCalcada Martim de FreitasCoimbra 3000-456Portugal University of Coimbra Coimbra Chemistry CenterDepartment of ChemistryCoimbra 3004-535Portugal Centre for Neuroscience and Cell Biology Uniuersity of CoimbraUC BiotechBiocant ParkCantanhede 3060-197Portugal

The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human *** quality evaluation is conventionally based on physicochemical parameters,but increasing attention has been paid to integrate physicochemical and biological ***,the regulatory use of fish in biological testing methods has been subject to various ethical and cost concerns,and in vitro cell-based assays have thus become an important topic of ***,the present study intends:(a) to evaluate the efficiency of two different sample pre-concentration techniques (lyophilisation and solid phase extraction) to assess the toxicity of municipal effluents on rat cardiomyoblast H9c2(2-1) cells,and (b) maximizing the use of the effluent sample collected,to estimate the environmental condition of the receiving *** gathered results demonstrate that the H9c2(2-1) sulforhodamine B-based assay is an appropriate in vitro method to assess biological effluent toxicity,and the best results were attained by lyophilising the sample as *** to its response,the H9c2(2-1) cell line might be a possible alternative in vitro model for fish lethal testing to assess the toxicity of municipal *** physicochemical status of the sample suggests a high potential for eutrophication,and iron exceeded the permissible level for wastewater discharge,possibly due to the addition of ferric chloride for wastewater *** general,the levels of carbamazepine and sulfamethoxazole are higher than those reported for other countries,and both surpassed the aquatic protective values for long-term exposure.

关键词： municipal wastewater treatment plant effluent Lyophilisation Solid phase extraction Cell-based assays H9c2(2-1)cell line SRB assay

Optimal management of prostate cancer with letha biology- state-of-the-art local therapy

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Asian Journal of Andrology 2015年第6期17卷 888-891,I0007页

作者： Brian f Chapin University of Texas mD Anderson Cancer Center Houston Texas 77030 USA.

Defining prostate cancer with lethal biology based upon clinical criteria is challenging. Locally advanced/High-Grade prostate cancer can be downstaged or even downgraded with cure in up to 60% of patients with primary therapy.1-5 However, what is known is that high-grade prostate cancers have a greater potential for recurrence and progression to metastatic disease, which can ultimately result in a patient＇s death.

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fragmentation Cross Sections of 158 AGeV Pb Projectiles

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Chinese Physics Letters 2007年第10期24卷 2800-2803页

作者： G. Sher m.I. Shahzad m. Hussain Physics Division PINSTECH Islamabad Pakistan Department of Physics University of the Punjab Lahore Pakistan

We investigate the fragmentation cross sections of 158 AGeV ^207Pb projectile interacting with different targets using CR39 nuclear track detectors. The exposure is made at SPS beam facility of CERN. The detectors are chemically etched to obtain data in the form of etched cone length. The nuclear and electromagnetic contributions to the measured total charge-changing cross sections are investigated. The estimated results are compared with those found in the literature for similar research work.

关键词： coated conductor buffer layer self-epitaxy CeO2

低危宫颈癌妇女单纯子宫切除术与根治性子宫切除术的比较

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中国临床药理学杂志 2024年第8期40卷 1159-1159页

作者： PLANTE m KWON J S fERGUSON S 王超群

回顾性资料显示,早期低危宫颈癌患者参数浸润发生率较低,这就提出了这些患者是否需要根治性子宫切除术的问题。然而,比较根治性和单纯性子宫切除术结果的大型随机试验数据缺乏。本研究进行了一项多中心、随机、非劣效性试验,比较了低危... 详细信息

回顾性资料显示,早期低危宫颈癌患者参数浸润发生率较低,这就提出了这些患者是否需要根治性子宫切除术的问题。然而,比较根治性和单纯性子宫切除术结果的大型随机试验数据缺乏。本研究进行了一项多中心、随机、非劣效性试验,比较了低危宫颈癌(病变≤2cm,间质浸润有限)患者的根治性子宫切除术和单纯性子宫切除术,包括淋巴结评估。主要结局是3年盆腔肿瘤复发(盆腔复发)。预先规定的3年盆腔复发组间差异的非劣效性界限为4个百分点。

关键词：根治性子宫切除术盆腔肿瘤回顾性资料间质浸润宫颈癌患者盆腔复发预先规定低危

THE EffECTS Of HETEROGENEITY IN mICROPROBE ANALYSIS

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电子显微学报 1991年第2期 203-204页

作者： f.A.Gimelfarb Lomonosov Institute of fine Chemical Technology

The concentration (c) of the element being defined inquantitative local analysis is evaluated by means of thecalculated or experimental calibrated characteristic I(c). It isusually plotted with the assumption that the specimen ishomogeneous in the emitting area. Remarkable systematic errors inmicroprobe analysis of heterogeneous materials can result withthis assumption especially if the materials are highlydistinguished in the adjacent phases investigated.

关键词： SImS EPmA THE EffECTS Of HETEROGENEITY IN mICROPROBE ANALYSIS

CRISPR-based genetic control strategies for insect pests

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Journal of Integrative Agriculture 2023年第3期22卷 651-668页

作者： Ying YAN Roswitha A.AUmANN Irina HÄCKER marc f.SCHETELIG Department of Insect Biotechnology in Plant Protection Institute for Insect BiotechnologyJustus-Liebig-University GiessenGiessen 35394Germany

Genetic control strategies such as the sterile insect technique have successfully fought insect pests worldwide. The CRISPR(clustered regularly interspaced short palindromic repeats) technology, together with high-quality genomic resources obtained in more and more species, greatly facilitates the development of novel genetic control insect strains that can be used in area-wide and species-specific pest control programs. Here, we review the research progress towards state-of-art CRISPR-based genetic control strategies, including gene drive, sex ratio distortion, CRISPRengineered genetic sexing strains, and precision-guided sterile insect technique. These strategies’ working mechanisms,potential resistance development mechanisms, and regulations are illustrated and discussed. In addition, recent developments such as stacked and conditional systems are introduced. We envision that the advances in genetic technology will continue to be one of the driving forces for developing the next generation of pest control strategies.

关键词： insect pest genetic control sterile insect technique gene drive genetic sexing strains CRISPR-Cas9

Polypyrrole Chitosan Cobalt ferrite Nanoparticles Composite Layer for measuring the Low Concentration of fluorene Using Surface Plasmon Resonance

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Chinese Physics Letters 2017年第5期34卷 111-114页

作者： A.R.Sadrolhosseini m.Naseri m.K.Halimah Department of Physics Faculty of ScienceMalayer University Department of Physics Faculty of ScienceUniversiti Putra Malaysia

fluorene is a polycyclic aromatic hydrocarbon, which is a hazardous toxic chemical in the environment. The measurement of low concentrations of fluorene is a subject of intense interest in chemistry and in the environment. Polypyrrole chitosan cobalt ferrite nanoparticles are prepared using the electrochemical method. The prepared layers are characterized using field emission scanning electron microscopy, fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The layers are used to detect fluorene using the surface plasmon resonance technique at room temperature. The composite layer is evaluated after detection of fluorene using atomic force microscopy. The fluorene is bound on the layer, and the shift of the resonance angle is about 0.0052°, corresponding to the limitation of 0.01 ppm.

关键词： Co NP Polypyrrole Chitosan Cobalt ferrite Nanoparticles Composite Layer for measuring the Low Concentration of fluorene Using Surface Plasmon Resonance