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981.
Patrick Mitashi Epco Hasker Veerle Lejon Victor Kande Jean-Jacques Muyembe Pascal Lutumba Marleen Boelaert 《PLoS neglected tropical diseases》2012,6(11)
While the incidence of Human African Trypanosomiasis (HAT) is decreasing, the control approach is shifting from active population screening by mobile teams to passive case detection in primary care centers. We conducted a systematic review of the literature between 1970 and 2011 to assess which diagnostic tools are most suitable for use in first-line health facilities in endemic countries. Our search retrieved 16 different screening and confirmation tests for HAT. The thermostable format of the Card Agglutination Test for Trypanosomiasis (CATT test) was the most appropriate screening test. Lateral flow antibody detection tests could become alternative screening tests in the near future. Confirmation of HAT diagnosis still depends on visualizing the parasite in direct microscopy. All other currently available confirmation tests are either technically too demanding and/or lack sensitivity and thus rather inappropriate for use at health center level. Novel applications of molecular tests may have potential for use at district hospital level. 相似文献
982.
983.
Jeannine Schumacker-Lambry Jean-Jacques Chateauneuf 《Review of Palaeobotany and Palynology》1976,21(4):267-294
The marls of Gelinden (Heersian stratotype or lowest part of the Landenian) contain rich assemblages of microplankton (98 species), including 73 species of dinoflagellates and 12 species of acritarchs. Some, probably new, are described in open nomenclature.Comparison between Gelinden assemblages and others from the Lower Tertiary and Upper Creataceous confirms the fully Tertiary aspect of the microplanktonic assemblages.Our results added to data obtained from macroflora and Foraminifera more accurately define the conditions of sedimentation into the “bay of Gelinden”: open sea, relatively deep water, not far from shore. 相似文献
984.
The development of inbreeding in rotation breeding schemes, sequentially using artificial insemination (AI) sires over generations, was investigated for a full AI scheme. Asymptotic prediction formulae of inbreeding coefficients were established when the first rotation list of AI sires (possibly related) was in use. Simulated annealing provided the optimal rotation order of sires within this list, when the sires were related. These methods were also used for subsequent rotation lists, needed by the exhaustion of semen stores for the first bulls. Simulation was carried out starting with groups of independent sires, with different sizes. To generate a yearly inbreeding rate substantially lower than 0.05% (considered to be within reach by conventional conservation schemes using frequent replacements), the results obtained showed that the number of sires should be at least 10–15 and that the same sires should be used during at least 50 years. The ultimate objective was to examine the relevance of implementing rotation in breeding schemes on the actual rare French cattle breeds under conservation. The best candidate for such a test was the Villard-de-Lans breed (27 bulls and 73 000 doses for only 340 females) and it turned out to be the best performer with an inbreeding coefficient of only 7.4% after 500 years and five different sire lists. Due to the strong requirements on semen stores and on the stability of population size, actual implementation of this kind of conservation scheme was recommended only in special (''niche'') cattle populations. 相似文献
985.
Gilda Grard Joseph N. Fair Deanna Lee Elizabeth Slikas Imke Steffen Jean-Jacques Muyembe Taylor Sittler Narayanan Veeraraghavan J. Graham Ruby Chunlin Wang Maria Makuwa Prime Mulembakani Robert B. Tesh Jonna Mazet Anne W. Rimoin Travis Taylor Bradley S. Schneider Graham Simmons Eric Delwart Nathan D. Wolfe Charles Y. Chiu Eric M. Leroy 《PLoS pathogens》2016,12(3)
986.
The purpose of this commentary is to stress that in mixed-valence systems, electron localization and electron delocalization
are competitive, the first being most often the stronger. In iron-sulfur clusters where a delocalized Fe(II)Fe(III) pair of
maximal spin exists, a minimum value of 1200 cm–1 is proposed for the resonance integral β parametrizing the electron delocalization.
Received: 12 January 1996 / Accepted: 23 January 1996 相似文献
987.
Mark Jorissen John Vereecke Edward Carmeliet Herman Van den Berghe Jean-Jacques Cassiman 《生物化学与生物物理学报:疾病的分子基础》1990,1096(1):52-59
Chloride channels and non-selective cation channels in the apical membranes of cultured nasal epithelial cells from three cystic fibrosis patients were investigated with the patch-clamp techinique. Outwardly rectifying chloride channels were found in 31% of the inside-out patches, but activity of this channel was never observed in cell-attached patches, even after stimulation with adrenaline. In 30% of the patches with chloride channels, activation occurred immediately after excision. Most of the channels, however, activated only after a membrane depolarization of +40 to +120 mV. Once activated, the chloride channels were indistinguishable from thsoe in nasal epithelial cells of control patients. Amiloride-insensitive, calcium- and voltage-dependent, non-selective cation channels were present in 11% of the cell-attached and 43% of the cell-free patches and could not be distinguished from those in controls. The cystic fibrosis chloride channel defect is conserved in cultured nasal epithelial cells, while a non-selective cation channel is apparently not affected. 相似文献