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【目的】 提升英文科技期刊在国际同行评议中对于审稿专家审稿意见造假这一学术不端行为的防范意识和能力,进一步完善其对学术不端的防范举措。【方法】 针对英文科技期刊办刊实践中所发现的审稿专家批量捏造或制造审稿意见的现象,探析其外在存续条件与内在动机,阐述这类造假意见的主要表现形式,进而总结出发现和防范此类学术不端审稿专家的有效方式。【结果】 在国际同行评议中,审稿专家审稿意见造假的学术不端情况并非个例,所提出的方式可有效发现和防范此类审稿专家。【结论】 在国际同行评议中,英文科技期刊需要针对审稿专家审稿意见造假的情况,进一步完善学术不端防范措施。  相似文献   
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Mercury species have aroused wide concern in the past several decades due to their high toxicity. However, it is still difficult to detect ultra-trace mercury species due to their biochemical transformation in complex samples. To establish a simpler and more sensitive method for pre-concentration and determination of trace mercury species, molybdenum disulfide (MoS2) nanosheets with sulfur-rich characteristics and enlarged interlayer spacing were prepared by a hydrothermal method coupled with a sonication-assisted liquid exfoliation method and acted as solid-phase extraction adsorbent. The nano-MoS2 had high adsorption capacity, fast adsorption rate and excellent selectivity towards mercury ions (Hg2+), methyl mercury (MeHg+) and ethyl mercury (EtHg+) in a wide pH range and complex matrices. And it could be easily regenerated by 4 mol L−1 HCl and reused several times. After optimizing HPLC-UV-HG-AFS conditions, a great linearity (1.0–10.0 μg L−1, R2 = 0.999 for Hg2+, MeHg+ and EtHg+), lower detection limits (0.017, 0.037 and 0.021 ng mL−1 for Hg2+, MeHg+ and EtHg+, respectively), relative standard deviations (<5%) and addition recoveries of the samples within 82.75–113.38% were observed. In summary, trace inorganic and organic mercury species in environmental and biological samples could be selectively enriched by the prepared nano-MoS2 and efficiently seperated and detected by HPLC-UV-HG-AFS. The present study will help provide a better strategy for environmental monitoring and health assessment of mercury pollutants.

As-synthesized few-layered molybdenum disulfide nanosheets were used as solid-phase extraction absorbent for ultra-trace mercury speciation analysis by HPLC-UV-HG-AFS.  相似文献   
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目的:研究甲氟喹对胶质瘤细胞的放射增敏作用,并对其机制进行初步探索。方法:取指数生长期的胶质瘤U251细胞,采用CCK-8检测法研究甲氟喹作用后U251细胞的存活率;细胞克隆形成实验评估甲氟喹对U251细胞的放射增敏效果;流式细胞技术检测甲氟喹联合X射线作用后U251细胞的活性氧水平和细胞凋亡率,探索联合作用下U251细胞的死亡机制。结果:甲氟喹对胶质瘤细胞具有良好的放射增敏效果,其对U251细胞的最大放射增敏比为1.64。X射线联合甲氟喹作用于U251细胞后,细胞的凋亡水平增加,活性氧水平增加,活性氧抑制剂谷胱甘肽能抑制X射线联合甲氟喹作用诱导的U251细胞凋亡。结论:甲氟喹对U251细胞有放射增敏作用,其作用机制可能为通过增加细胞活性氧水平、诱导细胞凋亡导致放射敏感性增加。  相似文献   
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目的本文旨在利用静息态功能磁共振成像技术,对额叶癫痫(Frontal Lobe Epilepsy,FLE)影响下的脑功能网络特征进行分析,寻找可能的FLE脑损伤客观评价指标。方法利用图论分析方法中的边、节点度、节点效率和介数中心度参数,获得患者组和对照组的这些参数计算结果并进行两样本t检验,分析FLE影响下的脑功能网络变化特征,并进一步研究这种变化特征与发作频率和病程之间的相关性。结果FLE患者组与对照组相比,边、节点度、节点效率和介数中心度参数均有重要统计学差异结果,且发现差异结果中与发作频率和病程存在一定的相关性。结论基于图论分析方法的静息态脑功能网络特征参数有可能作为FLE的评估指标,为FLE的评价提供依据。  相似文献   
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Background contextAlthough multiple mechanisms of device attachment to the spinous processes exist, there is a paucity of data regarding lumbar spinous process morphology and peak failure loads.PurposeUsing an in vitro human cadaveric spine model, the primary objective of the present study was to compare the peak load and mechanisms of lumbar spinous process failure with variation in spinous process hole location and pullout direction. A secondary objective was to provide an in-depth characterization of spinous process morphology.Study designBiomechanical and anatomical considerations in lumbar spinous process fixation using an in vitro human cadaveric model.MethodsA total of 12 intact lumbar spines were used in the current investigation. The vertebral segments (L1–L5) were randomly assigned to one of five treatment groups with variation in spinous process hole placement and pullout direction: (1) central hole placement with superior pullout (n=10), (2) central hole placement with inferior pullout (n=10), (3) inferior hole placement with inferior pullout (n=10), (4) superior hole placement with superior pullout (n=10), and (5) intact spinous process with superior pullout (n=14). A 4-mm diameter pin was placed through the hole followed by pullout testing using a material testing system. As well, the bone mineral density (BMD) (g/cm3) was measured for each segment. Data were quantified in terms of anatomical dimensions (mm), peak failure loads (newtons [N]), and fracture mechanisms, with linear regression analysis to identify relationships between anatomical and biomechanical data.ResultsBased on anatomical comparisons, there were significant differences between the anteroposterior and cephalocaudal dimensions of the L5 spinous process versus L1–L4 (p<.05). Statistical analysis of peak load at failure of the four reconstruction treatments and intact condition demonstrated no significant differences between treatments (range, 350–500 N) (p>.05). However, a significant linear correlation was observed between peak failure load and anteroposterior and cephalocaudal dimensions (p<.05). Correlation between BMD and peak spinous processes failure load was approaching statistical significance (p=.08). 30 of 54 specimens failed via direct pullout (plow through), whereas 8 of 54 specimens demonstrated spinous process fracture. The remaining cases failed via plow through followed by fracture of the spinous process (16 of 54; 29%).ConclusionsThe present study demonstrated that variation in spinous process hole placement did not significantly influence failure load. However, there was a strong linear correlation between peak failure load and the anteroposterior and cephalocaudal anatomical dimensions. From a clinical standpoint, the findings of the present study indicate that attachment through the spinous process provides a viable alternative to attachment around the spinous processes. In addition, the anatomical dimensions of the lumbar spinous processes have a greater influence on biomechanical fixation than either hole location or BMD.  相似文献   
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杀虫剂被广泛使用以来,对生态环境的污染、食物中的农药残留等问题引起人们日益关注,研究杀虫剂的酶促降解将为解决杀虫剂污染及残留提供新的途径,本文对常见几类杀虫剂的酶促降解及其研究进展予以综述。  相似文献   
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The Joint Research Centre of the European Commission develops instrumentation for detection of hazardous materials. In relation to this a new experimental facility was constructed for research into methods applying the detection of characteristic gamma rays subsequent to neutron irradiation. This includes the detection of prompt gamma rays from neutron inelastic scattering and neutron capture. For this purpose the device employs LaBr3 scintillation detectors. The paper investigates the applicability of the LaBr3 scintillation detector to PGNAA.  相似文献   
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BackgroundTics and Tourette syndrome are common problems evaluated by both the general pediatrician and pediatric neurologist. The common comorbidities of tics are well known, but the severe neurological complications are rare and may not be appreciated.MethodsThis is a retrospective case series and literature review.ResultsWe present here four adolescents with Tourette syndrome who had severe neurological complications secondary to motor tics. We provide the history, neurological examination, and radiological findings in addition to a review of previously reported cases of vascular and cervical cord complications associated with violent motor tics.ConclusionsWe highlight the importance of recognizing the presenting signs of these complications early and the need to vigorously treat violent motor tics to prevent significant neurological complications.  相似文献   
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赵铭力 《首都医药》2012,(12):48-49
目的观察养血口服液治疗产后贫血的临床疗效,为临床用药提供依据。方法将2010年2月~2011年5月期间收治的120例产后贫血妇女随机分为治疗组及对照组,每组60例。其中治疗组给予养血口服液口服,每次1支,每日2次;对照组给予速力菲0.1g,每日3次,4周一疗程。对比观察两组治疗前、后红细胞(RBC)、血红蛋白(Hb)、血细胞比容(HCT)、平均红细胞容积(MCV)、平均红细胞血红蛋白含量(MCH)、平均红细胞血红蛋白浓度(MCHC)、网织红细胞计数(RC)情况及疗效判定情况。结果治疗组总有效率96.67%,对照组总有效率90%;两组对比治疗组疗效优于对照组,差异明显具有统计学意义。两组比较治疗组起效速度明显快于对照组,差异明显有统计学意义。两组比较治疗组疗效快于对照组,差异明显有统计学意义。两组血红蛋白治疗前、后情况对比治疗组治疗后较治疗前疗效明显,具有统计学意义。对照组治疗后较治疗前疗效明显具有统计学意义。治疗组治疗后较对照组治疗后疗效明显,具有统计学意义。结论养血口服液补血速度快、血色素升高迅速、不良反应少是治疗产后贫血的最佳药物。  相似文献   
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