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101.
Sternal pores are important features for identification of male thrips, especially within the subfamily Thripinae. They vary in shape, size and distribution even between species of one genus. Their functional role is speculated to be that of sex- and/or aggregation pheromone production. Yet, sexual aggregations are not reported in Echinothrips americanus, known to have sternal pores, while we observed aggregations in Megalurothrips sjostedti, previously reported to lack them.We examined the sternal glands and pores of the thripine species E. americanus and M. sjostedti males, in comparison with those of Frankliniella occidentalis using light microscopy, as well as scanning and transmission electron microscopy. Pore plates of F. occidentalis were ellipsoid and medial on sternites III–VII, while in E. americanus they were distributed as multiple micro pore plates on sternites III–VIII. In M. sjostedti they appeared as an extremely small pore in front of the posterior margin of each of sternites IV–VII. Pore plate and pore plate area were distributed similarly on sternites III–VII in F. occidentalis. However, in E. americanus the total pore plate area increased significantly from sternites III to VIII. Ultrastructure of cells associated with sternal glands showed typical characteristics of gland cells that differ in size, shape and number. The function of sternal glands is further discussed on the basis of morphological comparisons with other thrips species.  相似文献   
102.
PDIA1 和EF1D 在左侧和右侧结肠癌差异表达的实验研究   总被引:1,自引:0,他引:1  
目的:初步确定蛋白质二硫化异构酶A1和延伸因子1-delta为左侧和右侧结肠癌中差异表达蛋白,为左侧和右侧结肠癌在肿瘤生物学方面的差异提供分子遗传学依据。方法:收集人左侧结肠癌(LSCC)和右侧结肠癌(RSCC)组织标本,进行二维凝胶电泳、质谱分析和生物信息学分离和鉴定左右侧结肠癌中差异表达蛋白质,进一步应用RT-PCR、Western Blot和免疫组织化学技术检测蛋白质二硫化异构酶A1和延伸因子1-delta在左侧和右侧结肠癌中的表达状态。结果:筛选并成功鉴定出左侧和右侧结肠癌中16种差异表达蛋白质,与右侧结肠癌比较,10种蛋白在左侧结肠癌表达上调,6种蛋白在左侧结肠癌表达下调,其中蛋白质二硫化异构酶A1在左侧结肠癌中表达上调,延伸因子1-delta在左侧结肠癌中表达下调,并通过RT-PCR、Western Blot和免疫组化方法证实了在左侧和右侧结肠癌中该两种蛋白表达的差异,与蛋白质组学结果一致。结论:左侧结肠癌和右侧结肠癌的蛋白质组存在差异,其中蛋白质二硫化异构酶A1和延伸因子1-delta在mRNA和蛋白水平均存在差异,这些可能是左侧和右侧结肠癌生物学行为差异的原因。  相似文献   
103.
刘伟  宛新荣  钟文勤 《兽类学报》2005,25(2):115-121
长爪沙鼠为典型的群居性鼠类。在自然条件下该鼠的集群贮食活动随时可为人工投放的种子食物所导引。本文依据组群个体合作贮食的习性,并结合剪趾和染毛双重标记的重捕跟踪方法设计了着重观测社群结构、群内个体序位、领域边界及相关社群行为的野外实验。据2(X)2年5月对4个相邻洞群的观测结果分析表明,应用此法便于在复杂的社群环境中直接确认组群成员及其属性,亦便于分辨同一组群或不同组群成员之间发生的行为事件及相关过程,且能在重复实验中得以验证。为在野外条件下定量研究长爪沙鼠社群行为提供了一种便捷可靠的观测方法。  相似文献   
104.
植物的根系分泌物是植物根系与周围环境之间的化学媒介,通过传递特定的信息,调节根际微环境,影响周围植物的生长。玉米(Zea mays L.)和荞麦(Fagopyrum esculentum Moench)是农作物间套作体系中典型的不能搭配的组合,其障碍因素尚不清楚。以玉米为受体植物,采用根悬空培养的方法,研究了荞麦、高粱(Sorghum bicolor(L.) Moench)根系分泌物对玉米根边缘细胞和根生长的影响。结果发现,玉米根边缘细胞离体培养条件下,用荞麦根系分泌物中的小分子物质处理4、8 h显著诱导边缘细胞凋亡、死亡,细胞活率分别比对照降低了71.6%和72.3%;荞麦根系分泌物中的小分子物质对玉米根产生氧化胁迫,诱导根SOD、POD和CAT活性分别比对照高22.6%、33.9%和107.2%,根中超氧阴离子(O2)和脯氨酸含量分别比对照高33.9%和49.8%;荞麦根系分泌物中小分子物质的胁迫使根细胞膜透性增大,与对照相比升高80.0%,丙二醛(MDA)含量比对照升高31.5%;荞麦根系分泌物中小分子物质诱导根内源激素(IAA)含...  相似文献   
105.
目的:探讨血清尿酸(UA)、超敏C反应蛋白(hs-CRP)、左心房内径(LAD)与老年永久性房颤的相关性。方法:选取2012年8月至2015年9月于首都医科大学宣武医院综合科住院的老年永久性房颤患者78例作为房颤组,选取同期住院窦性心律且无房颤病史的老年患者72例作为对照组,记录各组一般资料及超声心动图、尿酸、hs-CRP水平等,进行比较及相关性分析。结果:1与对照组相比,房颤组血清UA及hs CRP水平、左心房内径大小明显增高(P0.05),2以房颤是否发生为因变量,多因素logistic回归分析显示血清尿酸(OR=2.016,P=0.004)、左房内径(OR=4.180,P=0.001)和hs-CRP(OR=2.846,P=0.002)是老年永久性房颤发生的独立危险因素。3房颤组患者血清尿酸与hs-CRP水平呈正相关(r=0.28,P0.05),尿酸与左心房内径大小呈轻度正相关(r=0.12,P0.05)。结论:血清尿酸、hs-CRP、左房内径是老年永久性房颤发生的独立危险因素;尿酸参与的炎症反应和结构重构可能参与老年永久性房颤的发生。  相似文献   
106.
Hydrolysis of 3-methoxy-16alpha-nitro-14,17-ethenoestra-1,3,5(10)-trien-17beta-yl acetate under weakly basic conditions leads to formation of 3-methoxy-2'-oxopyrrolidino-[4',5':14beta,15beta]-estra-1,3,5 (10)-trien-17-one, the structure of which has been confirmed by X-ray analysis and some chemical transformations. The reactivity of 3-methoxy-16alpha-nitro-14,17-ethanoestra-1,3,5(10)-trien-17beta-yl acetate under various conditions of basic hydrolysis has been investigated. The derived compounds have been identified by means of NMR spectroscopy and X-ray analysis.  相似文献   
107.
In the present study, we documented the promising role of thyroid hormones status in animals in modulation of Na+–Pi transport activity in intestinal brush border membrane vesicles (BBMV) which was accompanied with alterations in BBM lipid composition and fluidity. Augmentation of net Pi balance in hyperthyroid (Hyper-T) rats was fraternized with accretion of Pi transport across BBMV isolated from intestine of Hyper-T rats as compared to hypothyroid (Hypo-T) and euthyroid (Eu-T) rats while Na+–Pi transport across BBMV was decreased in Hypo-T rats relative to Eu-T rats. Increment in Na+–Pi transport in intestinal BBMV isolated from Hyper-T rats was manifested as an increase in the maximal velocity (Vmax) of Na+–Pi transport system. Furthermore, BBMV lipid composition profile in intestinal BBM from Hyper-T was altered to that of Hypo-T rats and Eu-T rats. The molar ratio of cholesterol/phospholipids was higher in intestinal BBM from Hypo-T rats. Fluorescence anistropy of diphenyl hexatriene (rDPH) and microviscosity were significantly decreased in the intestinal BBM of Hyper-T rats and decreased in Hypo-T rats as compared to Eu-T rats which corroborated with the alteration in membrane fluidity in response to thyroid hormone status of animals. Therefore, thyroid hormone mediated change in membrane fluidity might play an important role in modulating Na+–Pi transport activity of intestinal BBM. (Mol Cell Biochem 278: 195–202, 2005)  相似文献   
108.
Matsuura M  Eguchi S 《Biometrics》2005,61(2):559-566
In a failure time analysis, we sometimes observe additional study subjects who enter during the study period. These late entries are treated as left-truncated data in the statistical literature. However, with real data, there is a substantial possibility that the delayed entries may have extremely different hazards compared to the other standard subjects. We focus on a situation in which such entry bias might arise in the analysis of survival data. The purpose of the present article is to develop an appropriate methodology for making inference about data including late entries. We construct a model that includes parameters for the effect of delayed entry bias having no specification for the distribution of entry time. We also discuss likelihood inference based on this model and derive the asymptotic behavior of estimates. A simulation study is conducted for a finite sample size in order to compare the analysis results using our method with those using the standard method, where independence between entry time and failure time is assumed. We apply this method to mortality analysis among atomic bomb survivors defined in a geographical study region.  相似文献   
109.
Reduction of the N1, N1′-C3-bridged di(benzimidazol-2-thione) (5) with a sodium/potassium alloy leads to the N1, N1′-C3-bridged dibenzotetraazafulvalene (6). One equivalent of 6 reacts with palladium diiodide to give the dicarbene complex 1,3-(2,2-dimethylpropane)-N1,N1′-bis(N3-ethylbenzimidazol-2-ylidene)palladium diiodide (7). The X-ray crystal structure analysis of 7 reveals a slightly distorted square-planar coordination environment for the palladium center and a Ccarbene-Pd-Ccarbene angle of 85.0(15)°. The carbene planes are oriented almost perpendicular (82.7° and 79.3°) to the PdI2C2 plane.  相似文献   
110.
The static fluid mosaic model of biological membranes has been progressively complemented by a dynamic membrane model that includes phospholipid reordering in domains that are proposed to extend from nanometers to microns. Kinetic models for lipolytic enzymes have only been developed for homogeneous lipid phases. In this work, we develop a generalization of the well-known surface dilution kinetic theory to cases where, in a same lipid phase, both domain and nondomain phases coexist. Our model also allows understanding the changes in enzymatic activity due to a decrease of free substrate concentration when domains are induced by peptides. This lipid reordering and domain dynamics can affect the activity of lipolytic enzymes, and can provide a simple explanation for how basic peptides, with a strong direct interaction with acidic phospholipids (such as beta-amyloid peptide), may cause a complex modulation of the activities of many important enzymes in lipid signaling pathways.  相似文献   
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