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( Dept.of Math. Faculty of Science Mansoura Egypt Dept.of Math. Faculty of Education Kafr El-Sheikh Tanta University Egypt.) 《生物数学学报》1997,(3)
1IntreductionTheliteratUreonmulti-Criteriondecisionmaking(MCDM)problemshas~tremendouslyintherecentpast.TwomajorareashaveevolvedwhiChbothconcentrateondecisionmakingwithseveralcriteria:multiobjectivedecisionmaking(MODM)andmulti-attributedecisionmaking(MADM).TheformerconcentratesoncontinuousdecisionspaceandthelatterfocusesonproblemswithdiscreteSPace.FuzzysettheoryhascontributedtoMODMproblemsaswellastheMADMProblems.ThegeneralMODMproblemcanbedeft.edLllasfollows:Twostagescangenerallybe… 相似文献
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微藻生物技术是较新的生物技术领域之一。藻的生物技术本质上与农业相同,即利用光合成机制生产生物量,用作食物、饲料、化学药品和能源。 培养微藻作生物量的主要优点为: 1.藻是很有效的生物系统,是以太阳能通过光合成生产有机化合物的。 相似文献
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ZHU JINGDE 《Cell research》1995,(1)
INTanDUCTI0NMyeloidcelldifferentiati0n,inwhichmultip0tentialprogenitorcellsarec0nvertedint00neofthesixmaturedifferentiatedcells,i.e.,erythr0cytes,platelets(megakary-ocytes),macr0phages,neutr0phils,e0sinophilsandbas0phils,involvestemporalre-gulati0nofexpression0fanumberoflineage-anddifferentiationstage-specificgenes.Understandingthedevel0pmentalspecificationoflineageaJswellasmaturationstageassociatedpatterns0fgeneexpressioninmyel0idcelldifferentiationrequiresanin-sightintothecontrol0findivid… 相似文献
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【目的】本研究旨在明确破茧率和破茧所需时间作为典型的专性幼虫期滞育昆虫麦红吸浆虫Sitodiplosis mosellana滞育解除指标的可行性,探讨蜕皮激素受体基因EcR和热激蛋白基因Hsp70和Hsp90在低温解除滞育中的作用。【方法】9月上旬采自田间的麦红吸浆虫滞育幼虫在低温(4℃)和自然变温处理不同时间(0~90 d)后转移至24℃化蛹,调查幼虫的破茧率、化蛹率及破茧和化蛹所需时间;采用qPCR技术分析4℃低温终止滞育并在24℃下恢复发育的幼虫EcR, Hsp70和Hsp90的mRNA水平。【结果】不同时间低温(4℃)和自然变温处理的麦红吸浆虫滞育幼虫破茧率和化蛹率以及破茧和化蛹所需时间均存在显著差异。未经低温(4℃)处理的幼虫在水分满足的条件下破茧率为71.3%,但均不能化蛹;低温(4℃)处理60 d内,随着处理时间的延长破茧率和化蛹率逐渐升高,破茧和化蛹所需时间逐渐缩短;与4℃低温处理30~60 d相比,自然变温处理30~60 d的幼虫化蛹率显著较低;4℃低温处理60 d和自然变温处理90 d后幼虫的化蛹率均超过91%。低温(4℃)处理显著提高了麦红吸浆虫幼虫EcR, Hsp70和Hsp90的表达量,其中处理30 d时其表达量最高,随着低温(4℃)处理时间的延长,表达量逐渐降低,大部分幼虫滞育解除后表达量趋于恒定。【结论】低温能显著促进麦红吸浆虫的滞育解除,效果优于9-10月自然变温;破茧率及破茧所需时间可作为评判麦红吸浆虫幼虫滞育强度的参考,但不能独立作为滞育解除的指标;EcR,Hsp70和Hsp90的表达水平与滞育强度密切相关,在麦红吸浆虫滞育解除中发挥潜在作用。 相似文献
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Herman AE Tisch RM Patel SD Parry SL Olson J Noble JA Cope AP Cox B Congia M McDevitt HO 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(11):6275-6282
Particular HLA class II allelic sequences are associated with susceptibility to type I diabetes. To understand the mechanism, knowledge of the molecular nature of the specific TCR/peptide/class II interactions involved in the disease process is required. To this end, we have introduced the diabetes-associated human class II HLA-DQ8 allele (DQA1*0301/DQB1*0302) as a transgene into mice and analyzed T cell responses restricted by this molecule to an important Ag in human diabetes, human glutamic acid decarboxylase 65. Hybridomas were used to determine the particular peptides from this Ag presented by HLA-DQ8 to T cells and to map the core minimal epitopes required for T cell stimulation. Analysis of these core epitopes reveals a motif and relevant features for peptides that are immunogenic to T cells when presented by HLA-DQ8. The major immunogenic epitopes of glutamic acid decarboxylase 65 do not contain a negatively charged residue that binds in the P9 pocket of the HLA-DQ8 molecule. PBMC from HLA-DQ8+ diabetic and nondiabetic individuals respond to these peptides, confirming that the mouse model is a useful tool to define epitopes of autoantigens that are processed by human APC and recognized by human T cells. 相似文献
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WEI MIN NI XIAO YA CHEN ZHI HONG XU HONG WEI XUE. * National Laboratory of Plant Molecular Genetics Institute of Plant Physiology Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Partner Group of Max-Pla 《Cell research》2002,(Z1)
Polar auxin transport plays a divergent role in plant growth and developmental processes including root and embryo development, vascular pattern formation and cell elongation. Recently isolated Arabidopsis pin gene family was believed to encode a component of auxin efflux carrier (G(?)lweiler et al, 1998). Based on the Arabidopsis pin1 sequence we have isolated a Brassica juncea cDNA (designated Bjpin1), which encoded a 70-kDa putative auxin efflux carrier. Deduced BjPIN1 shared 65% identities at protein level with AtPINl and was highly homologous to other putative PIN proteins of Arabidopsis (with highest homology to AtPIN3). Hydrophobic analysis showed similar structures between BjPINl and AtPIN proteins. Presence of 6 exons (varying in size between 65 bp and 1229 bp) and 5 introns (sizes between 89 bp and 463 bp) in the genomic fragment was revealed by comparing the genomic and cDNA sequences. Northern blot analysis indicated that Bjpin1 was expressed in most of the tissues tested, with a relatively h 相似文献
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Stefferl A Schubart A Storch M Amini A Mather I Lassmann H Linington C 《Journal of immunology (Baltimore, Md. : 1950)》2000,165(5):2859-2865
Experimental autoimmune encephalomyelitis (EAE) induced by sensitization with myelin oligodendrocyte glycoprotein (MOG) is a T cell-dependent autoimmune disease that reproduces the inflammatory demyelinating pathology of multiple sclerosis. We report that an encephalitogenic T cell response to MOG can be either induced or alternatively suppressed as a consequence of immunological cross-reactivity, or "molecular mimicry" with the extracellular IgV-like domain of the milk protein butyrophilin (BTN). In the Dark Agouti rat, active immunization with native BTN triggers an inflammatory response in the CNS characterized by the formation of scattered meningeal and perivascular infiltrates of T cells and macrophages. We demonstrate that this pathology is mediated by a MHC class II-restricted T cell response that cross-reacts with the MOG peptide sequence 76-87, I GEG KVA LRIQ N (identities underlined). Conversely, molecular mimicry with BTN can be exploited to suppress disease activity in MOG-induced EAE. We demonstrate that not only is EAE mediated by the adoptive transfer of MOG74-90 T cell lines markedly ameliorated by i.v. treatment with the homologous BTN peptide, BTN74-90, but that this protective effect is also seen in actively induced disease following transmucosal (intranasal) administration of the peptide. These results identify a mechanism by which the consumption of milk products may modulate the pathogenic autoimmune response to MOG. 相似文献