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A rapid, sensitive and specific high‐performance thin‐layer chromatographic (HPTLC) method was developed and validated for determination of gliotoxin in Aspergillus infected immunocompromised patients with invasive aspergillosis (IA). Densitometric analysis of gliotoxin was carried out in the absorbance mode at 254 nm after single‐step extraction with chloroform. The method uses TLC aluminum plates pre‐coated with silica gel 60F‐254 as a stationary phase and toluene–isoamyl alcohol–methanol (10:0.5:0.5, v/v/v) as mobile phase, which gives compact spot of gliotoxin (Rf = 0.51). The calibration curve was linear (r2 ≥ 0.994) between peak area and concentration in the tested range of 100–1000 ng spot?1 with minimum detectable range 0.025 ng μ?1 of serum sample. The mean ± SD value of slope and intercept of the standard chromatogram of gliotoxin were found to be 523.2 ± 1.555635 and 915.8 ± 30.68843, respectively. The developed method is simple, rapid, precise and less costly than earlier diagnostic methods, and different serum samples can be run on a single TLC plate for comparative analysis. The proposed method can be used to analyze gliotoxin in patient serum for easy, rapid and cost‐effective diagnosis of IA. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Minimum symbol error rate multiuser detection using an effective invasive weed optimization for MIMO/SDMA–OFDM system
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Kala Praveen Bagadi Susmita Das 《International Journal of Communication Systems》2014,27(12):3837-3854
Space division multiple access–orthogonal frequency division multiplexing system has become a potential wireless communication system by offering high spectral efficiency, performance and capacity. This article deals with minimum symbol error rate (MSER)‐based multiuser detection (MUD) technique for the space division multiple access–orthogonal frequency division multiplexing system using an efficient invasive weed optimization (IWO) algorithm. The IWO algorithm is used for finding optimal weights such that the probability of error is directly minimized rather than minimizing the mean square error. Because of this, the MSER MUD is able to detect users even in overload scenario, where the number of users is more than the number of receiving antennas, unlike several classical detection techniques. The IWO is inspired from the nature of invasive colonization of weeds and relatively simple compared with other optimization techniques. The bit error rate performance of the proposed IWO‐aided MSER MUD is found to be better than minimum means square error and differential evolution algorithm‐aided MSER MUDs. Simulation results show that the proposed IWO MSER achieves faster convergence and lower complexity compared with the differential evolution MSER MUD. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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外来种喜旱莲子草的克隆生长特性 总被引:2,自引:0,他引:2
通过对外来种喜旱莲子草(Alternanthera philoxeroides(Mart.)Griseb)生长指标的测定和分析,研究了它的克隆生长规律,并探讨丁它的觅食行为.在一个生长季节内,喜旱莲子草生物量增加了近30倍,一级葡萄茎分株数增加了近50倍,最长的一级葡萄茎长度增长了近40倍,一级葡萄茎总长度增长了近13倍;一、二、三级葡萄茎上的总分株数增加了近130倍,3个级别匍匍苇总长度增长了近28倍.通过各级葡萄茎个数,葡萄茎总长度和葡萄茎总分株数比较发现,二级葡萄茎比一、二级葡萄苇生长的都要快,而一级葡萄茎的间隔物平均长度远远大于二级和三级葡萄茎.克隆植物的觅食行为与它的克隆生长紧密相连,从觅食行为来看,喜旱莲子草克隆构型随生长季节的变化说明了它对生长季节具有很强的适应性.这种快速克隆生长的特性和对生长季节的适应性有利于喜旱莲子成功入侵新的生境。 相似文献
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Volker Runde 《Transactions of the American Mathematical Society》2006,358(1):391-402
Let be a locally compact group, and let denote the space of weakly almost periodic functions on . We show that, if is a -group, but not compact, then the dual Banach algebra does not have a normal, virtual diagonal. Consequently, whenever is an amenable, non-compact -group, is an example of a Connes-amenable, dual Banach algebra without a normal, virtual diagonal. On the other hand, there are amenable, non-compact, locally compact groups such that does have a normal, virtual diagonal.
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目的探讨三维超声引导下VACORA真空微创穿刺活检系统在乳腺良性疾病诊疗中的应用价值。方法选取术前诊断为乳腺良性肿块患者103例(223个肿块),经二维超声引导治疗54例(二维组),经实时三维超声引导治疗49例(三维组),记录两组患者肿块容积、手术切除条数、手术耗时、术后血肿发生情况及血肿吸收情况。结果全部肿块均成功引导切除,两组患者手术耗时无明显差异(P>0.05),三维组肿块切除条数及术后血肿发生率均明显少于二维组(均P<0.05),而且血肿0.16~3.80ml者平均吸收时间均显著明显短于血肿4.7~19.5及25.2~32.0ml者(均P<0.01)。两组患者术后随访1~12个月均无复发。结论超声引导VACORA真空微创穿刺活检系统适用于体积<2.4ml乳腺良性肿块的微创切除,实时三维超声引导定位准确、安全、损伤小,是乳腺肿块微创切除的一种有效方法。 相似文献
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Zhuo Liu Ye Ma Han Ouyang Bojing Shi Ning Li Dongjie Jiang Feng Xie Dan Qu Yang Zou Yue Huang Hu Li Chaochao Zhao Puchuan Tan Min Yu Yubo Fan Hao Zhang Zhong Lin Wang Zhou Li 《Advanced functional materials》2019,29(3)
Changes in endocardial pressure (EP) have important clinical significance for heart failure patients with impaired cardiac function. As a vital parameter for evaluating cardiac function, EP is commonly monitored by invasive and expensive cardiac catheterization, which is not feasible for long‐term and continuous data collection. In this work, a miniaturized, flexible, and self‐powered endocardial pressure sensor (SEPS) based on triboelectric nanogenerator (TENG), which is integrated with a surgical catheter for minimally invasive implantation, is reported. In a porcine model, SEPS is implanted into the left ventricle and the left atrium. The SEPS has a good response both in low‐ and high‐pressure environments. The SEPS achieves the ultrasensitivity, real‐time monitoring, and mechanical stability in vivo. An excellent linearity (R 2 = 0.997) with a sensitivity of 1.195 mV mmHg?1 is obtained. Furthermore, cardiac arrhythmias such as ventricular fibrillation and ventricular premature contraction can also be detected by SEPS. The device may promote the development of miniature implantable medical sensors for monitoring and diagnosis of cardiovascular diseases. 相似文献
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Advances in cellular recordings using engineered devices have greatly increased the understanding in biological systems. These recordings have been an essential part in a broad variety of fields ranging from neuroscience and cardiology to cell biology and have been applied both in research and clinical applications. To provide less tissue damage, reduce foreign‐body response, and enhance long‐term signal stability, the engineered devices need to be minimally invasive. Pursuing these goals, recently, nanoelectronic probes with improved mechanical, chemical, and biocompatible properties have been developed. Moreover, innovative and automated insertion techniques of neural probes have been reported, further progressing toward a high‐bandwidth brain–machine interface system. In this progress report, recent progress in materials, device designs, and implementation techniques aiming for minimally invasive cellular recordings (both in vivo and in vitro) is highlighted, and future directions in these areas are proposed. 相似文献