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41.
苏爱 《中国优生与遗传杂志》2004,12(3):43-44
目的与方法本文对189例自然流产、闭经、发育不全患者进行细胞遗传学检查,结果发现异常核型16例,异常核型涉及1、3、4、5、6、7、8、9、10、 15、X、Y染色体.其中平衡易位10例,性染色体异常3例,大Y染色体3例.结论染色体异常是导致流产、闭经、性发育异常的重要遗传因素,应引起临床医师的高度重视. 相似文献
42.
43.
Evans DL Kaur H Leary J Praveen K Jaso-Friedmann L 《Developmental and comparative immunology》2005,29(12):1049-1064
Nonspecific cytotoxic cells (NCC) are the first identified and most extensively studied killer cell population in teleosts. NCC kill a wide variety of target cells including tumor cells, virally transformed cells and protozoan parasites. The present study identified a novel evolutionarily conserved oligodeoxynucleotide (ODN) binding membrane protein expressed by channel catfish (Ictalurus punctatus) NCC. Peptide fingerprinting analysis of the ODN binding protein (referred to as NCC cationic anti-microbial protein-1/ncamp-1) identified a peptide that was used to design degenerate primers. A catfish NCC cDNA library was used as template with these primers and the PCR-amplified product was sequenced. The translated sequence contained 203 amino acids (molecular mass of 22,064.63 Da) with characteristic lysine rich regions and a pI=pH 10.75. Sequence comparisons of this protein indicated similarity to zebrafish (51.2%) histone family member 1-X and (to a lesser extent) to trout H1. A search of EST databases confirmed that ncamp-1 is also expressed in various tissues of channel catfish as well as zebrafish. Inspection for signature repeats in ncamp-1 and comparisons with histone-like peptides from different species indicated the presence of multiple lysine based motifs composed of AKKA or PKK repeats. The novel protein was cloned, expressed in E. coli and the recombinant was used to generate rabbit anti-serum. The recombinant ncamp-1 bound GpC and CpG ODNs and was detected with homologous anti-ncamp-1 polyclonal antibodies. Western blots of NCC membranes using anti-ncamp-1 serum detected a 29 kDa protein. Binding competition experiments demonstrated that anti-ncamp-1 antibodies and GpC bound to the same protein on NCC. Two different truncated forms of ncamp-1 as well as the full-length recombinant protein exhibited anti-microbial activity. The present study demonstrated the expression by NCC of a new membrane protein that may participate in the recognition of bacterial DNA and as such participate in innate anti-microbial immune responses in teleosts. 相似文献
44.
Summary This short paper summarizes the basic concept and the technology of a new computed radiographic system which uses an energy-storage phosphorus panel called Imaging Plate as an image sensor. The Imaging Plate can be used to obtain radiographs in exactly the same way as the screen-film combination is used in conventional radiography. The system eliminates the drawbacks of conventional screen-film radiography by combining digital image processing and digitization of the x-ray energy pattern utilizing scanning laser stimulated luminescence.The major part of this paper was originally delivered at the 1984 AAPM Annual Summer School which was held on July 22–27 at University of Notre Dame, USA. Modified for the publication in the Neurosurgical Review. 相似文献
45.
T. M. Robertson J. E. Brown B. A. Fielding R. Hovorka M. D. Robertson 《Nutrition Bulletin》2021,46(1):52-59
With an increasing prevalence of diabetes worldwide, effective dietary strategies for blood glucose control are crucial. As carbohydrates make up approximately 50% of the diet, it is neither practical nor advisable to avoid them altogether. Most of the carbohydrate in the diet is derived from starch, found in potatoes, pasta, rice and bread. These foods are often processed in some way before consumption, yet little is known about the effects processing, such as chilling and reheating, has on the glycaemic response, particularly when the food is consumed in the context of a mixed meal. This article introduces the SPUD project, a BBSRC DRINC‐funded initiative. Taking the potato as the model carbohydrate, this project will investigate, via in vitro and in vivo studies, the effects of domestic food processing techniques on the glycaemic response. A final study, utilising intrinsically labelled potato and a dual stable isotope methodology, will model glucose flux data to determine the underlying mechanisms of action. 相似文献
46.
Leslie Sim PhD Carol B. Peterson PhD 《The International journal of eating disorders》2021,54(11):2046-2056
Differential susceptibility, a reconceptualization of the diathesis-stress model of psychopathology, describes gene–environment interactions that reflect individual differences in responsiveness to environmental influences, both detrimental and beneficial. This model has been described metaphorically by the classification of orchids, which thrive under optimal care but wither under adverse conditions, and dandelions, which weather broad environmental circumstances but are less responsive to careful cultivation. Etiological research in the field of eating disorders has largely focused on the identification of specific behavioral phenotypes, temperamental traits, genotypes and neurobiological processes that confer risk. In this article, we propose that these putative vulnerability factors represent phenotypes and endophenotypes of a genetic predisposition towards environmental sensitivity. We assert that this sensitivity not only transmits eating disorder risk but also confers resilience, depending on the circumstances. In particular, we propose that differential susceptibility can be used as a framework to organize disparate temperamental and neurobiological findings and their complex interplay with various developmental, environmental and sociocultural influences to increase eating disorder risk and treatment responsiveness. Finally, we assert that viewed through the lens of differential susceptibility, sensitivity can be leveraged to refine our interventions and develop novel treatment and prevention strategies to support favorable outcomes for individuals with eating disorders. 相似文献
47.
管靖华 《中国医学物理学杂志》2004,21(1):51-52,48
信息社会的发展,在很大程度上取决于信息与信号处理技术的先进性.数字信号处理技术的出现改变了信息与信号处理技术的整个面貌,测量仪器技术与计算机技术深层次的结合正引起测试仪器领域里一场新的革命,一种全新的仪器结构概念导致了新一代仪器--虚拟仪器的出现,它是现代计算机技术、通信技术里测量技术相结合的产物,是传统仪器观念的一次巨大变革.它的出现使得人类的测试技术进入了一个新的发展纪元.本文介绍了用"弱电与非电信号处理系统"这一虚拟仪器进行生物非电信号的采集和分析的应用过程. 相似文献
48.
Iterative reconstruction algorithms 总被引:7,自引:0,他引:7
In this paper a survey of recent results on iterative reconstruction algorithms is given. These results, many of which have not yet appeared elsewhere, are applicable to a very general formulation of the reconstruction problem based on the series expansion approach. A set of optimization criteria and a number of iterative reconstruction algorithms are stated, together with theorems on the convergence of the algorithms to optimum images. The efficacy of the algorithms is compared to that of the convolution method. In particular, the falseness of the claim that ART and the backprojection method are the same is demonstrated. 相似文献
49.
XU Xiu lin ZHU Nai shuo Department of medical instrumentation Shanghai medical instrumentation college China Lab.of molecular immunology School of life sciences Fudan University Shanghai China 《中国生物医学工程学报(英文版)》2002,(2)
INTRODUCTION From integrallevel and celllevel,the research of organism and diseasediagnosishave already entered molecular level.Molecular biology is the science to researchstructure and function of organism macromolecule.Based on differentgene code se-… 相似文献
50.
五种免疫相关性心血管疾病的免疫学研究 总被引:4,自引:0,他引:4
对扩张型心肌病、风湿性心脏病,原发性高血压,冠心病及肥厚型心肌病进行外周血清可溶性白细胞介素2受体,T淋巴细胞亚群及自然杀伤细胞活性的检测,并与健康对照组比较,结果显示:DCM组,RHD组及EHT组的sIL-2R明显高于NC组,而DCM、RHD风湿活动组的NK活性低于NC组,EHT组NK活性高于NC组。 相似文献