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1.
Nine pairs of polymerase chain reaction (PCR) primers that amplify polymorphic microsatellite loci in the desert locust, Schistocerca gregaria (Forskal), were developed using a magnetic bead‐based enrichment protocol. A sample of 48 locusts collected during the 1993 and 1995 upsurge periods in Eritrea, East Africa, were genotyped. The number of alleles per locus ranged from six to 20; the average was 12.67. Allelic distributions were significantly different between samples from different localities.  相似文献   
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In primates, females typically drive the evolution of the social system and present a wide diversity of social structures. To understand this diversity, it is necessary to document the consistency and/or flexibility of female social structures across and within species, contexts, and environments. Macaques (Macaca sp.) are an ideal taxon for such comparative study, showing both consistency and variation in their social relations. Their social styles, constituting robust sets of social traits, can be classified in four grades, from despotic to tolerant. However, tolerant species are still understudied, especially in the wild. To foster our understanding of tolerant societies and to assess the validity of the concept of social style, we studied female crested macaques, Macaca nigra, under entirely natural conditions. We assessed their degree of social tolerance by analyzing the frequency, intensity, and distribution of agonistic and affiliative behaviors, their dominance gradient, their bared‐teeth display, and their level of conciliatory tendency. We also analyzed previously undocumented behavioral patterns in grade 4 macaques: reaction upon approach and distribution of affiliative behavior across partners. We compared the observed patterns to data from other populations of grade 4 macaques and from species of other grades. Overall, female crested macaques expressed a tolerant social style, with low intensity, frequently bidirectional, and reconciled conflicts. Dominance asymmetry was moderate, associated with an affiliative bared‐teeth display. Females greatly tolerated one another in close proximity. The observed patterns matched the profile of other tolerant macaques and were outside the range of patterns of more despotic species. This study is the first comprehensive analysis of females’ social behavior in a tolerant macaque species under natural conditions and as such, contributes to a better understanding of macaque societies. It also highlights the relevance of the social style concept in the assessment of the degree of tolerance/despotism in social systems. Am. J. Primatol. 75:361‐375, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Since their discovery over 100 years ago,sphingolipids have caught the eyes and the imagination of scientists.Modern science has made many new insights on the cell biology and day-to-day functions of many integral sphingolipids,especially those of ceramids.Ceramide is recognized as a vital second messenger in the signal transduction process mediated by receptors of many cytokines and growth factors.A great part of our current understanding of ceramide has been achieved from apoptosis-related studies,however recent data in the fields of immunology,endocrinology and neurobiology,also suggest a fundamental involvement of ceramide in the onset of diseases.Therefore,understanding the diology of ceramide could be a key to unraveling many biological mechanisms and provide information for the treatment of some common diseases.  相似文献   
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为研究中国水仙类黄酮代谢调控网络,从中国水仙(Narcissus tazetta var.chinensis)中克隆得到一个R2R3-MYB基因,命名为NtMYB7(GenBank登录号:MF522208)。序列分析表明,NtMYB7基因cDNA开放阅读框(ORF)为753bp,编码250个氨基酸。氨基酸多重序列比对分析发现,NtMYB7含有R2和R3保守结构域,属于R2R3-MYB家族;系统进化树分析结果显示,NtMYB7与花青素合成抑制因子聚为一类。实时荧光定量PCR分析发现,NtMYB7基因在中国水仙不同时期花瓣和副冠以及不同器官中均有表达,且NtMYB7基因在鳞茎盘中表达量最高。瞬时表达分析发现,NtMYB7使花青素合成激活因子StMYB诱导产生的红色变浅;定量PCR分析表明,NtMYB7基因显著抑制烟草黄酮醇代谢分支FLS基因的表达,同时抑制StMYB激活的花青素和原花青素合成结构基因的表达。研究结果初步判断,NtMYB7基因是中国水仙类黄酮代谢途径的抑制因子。  相似文献   
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An enzyme-linked immunofiltration assay (ELIFA) and a microtitre plate enzyme-linked immunosorbent assay (ELISA) were developed and compared for their ability to detect staphylococcal enterotoxin B (SEB). The double antibody capture format was used for both assays. Factors which improved the sensitivity of the ELIFA system were (1) addition of casein and thimerosal to the antigen dilution buffer; (2) addition of polyethylene glycol (MW 6000) to the detection and conjugate antibody dilution buffers; and (3) washing with diethanolamine buffer prior to addition of the substrate/chromogen. The ELIFA system had a turnaround time of approximately 1 h and a detection limit of 1 ng/mL of purified SEB. The ELISA had a total turnaround time of 21 h, or 3 h using plates pre-coated overnight with the capture antibody. The detection limit of the ELISA for purified SEB was 0.05 ng/mL. The detection limit of SEB in cheese samples spiked with purified enterotoxin and subjected to a simple extraction procedure was 1 ng/mL and 0.1 ng/mL of extract, with the ELIFA and the ELISA, respectively.  相似文献   
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An isolate of Verticillium dahliae obtained from Uganda was highly virulent to young cotton plants under greenhouse conditions. A hyaline variant which often appeared in culture was as virulent as the parent isolate, but preliminary experiments indicated that it did not survive as long in unsterile soil. The parent isolate grew rapidly in cotton plants after root inoculation and was isolated from stems and leaves well before the appearance of disease symptoms visible to the naked eye.
Protopectinase was produced in the absence of pectic materials, but more active preparations were obtained when media contained pectic substances. In general, there was a close correspondence between the protopectinase activity of culture filtrates and the toxicity of these filtrates to parenchymatous cells. Some separation of the two activities was obtained by heating enzyme solutions or by plasmolysing the test tissue.
Protopectinase solutions had little pectinesterase activity but rapidly reduced the viscosity of solutions of pectic substances. In general, the properties of protopectinase and the viscosity-reducing enzyme were similar.
Young cotton shoots wilted rapidly when placed in cell-free filtrates from cultures of the pathogen. Wilting was delayed under conditions unfavourable for transpiration. Evidence was obtained which showed that wilting was caused by the uptake of thermostable compounds of high molecular weight which impeded the upward flow of the vascular sap. Pronounced vascular browning was obtained only when solutions containing protopectinase were used. Wilting and vascular browning were obtained with solutions having little pectinesterase activity; in contrast, a solution having high pectinesterase activity produced relatively little vascular browning.  相似文献   
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AJMAL, S. & IQBAL, M., 1992. Structure of the vascular cambium of varying age and its derivative tissues in the stem of Ficus rumphii Blume. The cambial cells of Ficus rumphii and their derivatives vary in size and number with the age of the tree. The fusiform initials, vessel elements, sieve-tube members, xylem fibres and phloem fibres are relatively short in the terminal part of the stem axis, consistently longer down the stem reaching a maximum, and short again in the main trunk. The width of the respective cells shows a similar variation. The ray cell initials increase both in number and size, and form rays of varying dimensions. Uniseriate and biseriate cambial rays are abundant, while multiseriate rays are especially sparse in the young shoot. The proportion of uni- and biseriate rays falls in the lower part of the stem whereas that of multiseriate rays increases. Likewise, short cambial rays are abundant in young branches but their frequency decreases in the trunk region, leading to a rise of the tall ray population. The rays in the phloem and xylem regions reflect a similar variation pattern with certain fluctuations. The overall proportion of the rays increases in the older part of the axis, reaching a maximum tangential area in the trunk. The transectional area of vessel elements remains more or less constant down to the base after an initial increase in the terminal region, while the sieve-tube proportion tends to be constant in the basal region after a consistent gain from the tree top basewards.  相似文献   
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ABSTRACT Overabundant elk (Cervus elaphus) populations have become a significant problem in many areas of North America. This is particularly true for protected areas where high densities of elk can cause long-term ecological degradation. When lethal control is not acceptable in these environments, resource managers must often consider alternative methods for reducing the size of resident elk populations. A potential management alternative is controlling the fertility of female elk. A promising new approach to wildlife contraception involves the use of biodegradable implants containing the gonadotropin-releasing hormone (GnRH) agonist leuprolide. During fall 2002-spring 2004, we compared pregnancy rates, reproductive behavior, daily activity patterns, and body condition of 17 free-ranging female elk treated with a leuprolide formulation with 17 untreated females, in Rocky Mountain National Park, Colorado, USA. After treatment, the pregnancy rate of treated elk was 0%, whereas 79% of control elk became pregnant. The effects of treatment were reversed the subsequent year with the pregnancy rate of treated females 100% compared with 91% for controls. Reproductive behaviors were similar for treated and control elk during the breeding and postbreeding seasons; treated elk did not exhibit postrut reproductive behaviors. Moreover, we found no differences in daily activity patterns of experimental groups during the breeding or postbreeding seasons. Treated elk did not show improved body condition over pregnant females. Instead, treated females catabolized proportionately more body fat during winter after treatment and at a higher rate than pregnant control elk. However, this effect was reversed the next spring with no difference in body fat between treated and control elk. We conclude from this experiment that leuprolide, administered as a controlled release formulation, offers a safe and effective method of controlling fertility in free-ranging female elk. However, practical application is limited by treatment duration and the need to treat females before the breeding season.  相似文献   
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