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21.
Primer walking of cloned DNA is a standard research tool. It has been used in the past to determine the sequence of individual clones of interest. With the expansion of DNA sequencing capacity the need to be able to walk larger numbers of clones has become necessary. Our laboratory is a mid-sized genomics facility. In conjunction with the Advanced Biomedical Computing Center (ABCC) we have developed methods for automating the primer selection, DNA sequencing, contig assembly and sequence analysis for clones arrayed in microtiter format. This approach has allowed us to walk 475 clones (five microtiter plates) selected from a cDNA library.  相似文献   
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Terrorism: A Reference Handbook, Stephen Atkins, Santa Barbara, ABC-CLIO (1992), 199 pp. Terrorism: Roots, Impact, Responses, Lawrence Howard (Ed.), Prager, New York (1992), 193 pp. Hostage-Taking Terrorism: Incident Response Strategy, Alastair MacWillson, St Martins, New York (1992), 263 pp.  相似文献   
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This paper analyses the determination of visibility of journals in which researchers of INRA (National Institute for Agricultural Research) publish. The corpus is comprised of 671 articles published over a period of four years in 258 journals. The advantage of the method applied for determining the visibility of journals is that it combines two approaches: a) bibliometric indicators (coverage by the ISI-publications and by two specific French databases) and b) experts' opinions (10 economists and sociologists). The main results are: a) There is a convergence between the opinion of the experts and «visibility» in the databases, b) The impact factor confirms the main opinions of the experts. The first journals ranked by the experts and JCR Social Sciences are the same but represent only 40 per cent of the total journals analysed. The other journals were revealed by the experts and French databases.«Whoever seeks to pass a balanced but lucid judgement on the general trends of the activity carried out by the profession to which he belongs, is liable to say either banalities or to hurt his colleagues»The notion which we retain of core is that which is successively and conjointly validated by the experts and by the major databases representative of the field.This study was financed by the Department of Rural Economy and Sociology of INRA.  相似文献   
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The seroprevalence of HIV-1 and HIV-2 among pregnant women in Maputo, the capital of Mozambique, was compared between the years 1982/83, 1988 and 1990. None of the 432 serum samples collected in 1982/83 was positive for HIV antibodies whereas in 1988 the HIV-1 and HIV-2 seroprevalence was 0.4% (2/500) and 0.6% (3/500), respectively, and in 1990 0.6% (12/2014) and 0.2% (4/2014), respectively. These results indicate that HIV infection has been introduced recently in Maputo and is spreading at a slow rate among women.  相似文献   
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Aqueous extracts of the coralline red algaeBossiella orbigniana have been shown to catalyze the enzymatic oxidation of arachidonic acid to a previously unreported ω6 eicosapentaenoic acid product. This unique fatty acid contains a conjugated tetraene with absorption maxima at 293, 306, and 321 nm, and was identified by spectral methods as 5(Z),8(Z),10(E),12(E),14(Z)-eicosapentaenoic acid. The compound was given the trivial name bosseopentaenoic acid. Under experimental conditions, production of bosseopentaenoic acid was linear up to 2 hr and dioxygen was consumed. Bosseopentaenoic acid, along with several other conjugated tetraenes, was also present in the algae endogenously as revealed by a comparison of the ultraviolet (UV) spectra and the high-performance liquid chromatographic (HPLC) pattern of the purified product and the organic extract ofBossiella.  相似文献   
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We will analyze the economic sensitivity of new energy-saving technologies to weather, future energy price, and system lifetime uncertainties. Graphical rate of return analysis is employed. A representative residential solar water heating investment is analyzed to illustrate the impact of uncertainties. The wide range of reasonable rates of return found suggests some considerations for policy makers and some areas of future research.  相似文献   
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