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901.
Albert C. F. Lam Daniel H. C. Chan Tony M. F. Tong Mary H. Y. Tang Steven Y. F. Lo Ivan F. M. Lo Stephen T. S. Lam 《黑龙江环境通报》2006,26(11):1018-1020
We present the first confirmed case by molecular analysis of a metaphyseal chondrodysplasia, McKusick type, in a 22-week fetus. Two novel compound heterozygous mutations, 64T> A and 79G > T, were found in the highly conserved regions of the RMRP gene. Twenty-two heterozygous g.1018 T> C mutations, two homozygous g.1018 T> C mutations, two heterozygous insertion mutations g.799_g.800insC and one heterozygous insertion mutation g.849_g.850insT were found among 100 normal controls. Careful radiological examination of the fetus for skeletal dysplasia allowed definitive diagnosis, proper genetic counselling and future prenatal diagnosis. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Daniel C. L. Satgé Marie-Annick Laumond François Desfarges Marie-Pierre R. Chenard 《黑龙江环境通报》2001,21(4):284-288
A therapeutic abortion was conducted on a 17-week-old male fetus with a large umbilical cord teratoma associated with an exomphalos. A review of the literature revealed ten other cases of umbilical cord teratoma and shows that these tumors have a very polymorphic presentation. Four fetuses and infants died from various causes indicating that there is a need for close follow-up of pregnancies with umbilical cord teratoma. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
906.
Visual techniques for the detection of water quality trends: Double-mass curves and cusum functions 总被引:1,自引:0,他引:1
Daniel A. Cluis 《Environmental monitoring and assessment》1983,3(2):173-184
There is a great need for quantitative techniques to assess changes in water quality related to progressive watershed land-use developments, water-related impoundments or to evaluate the impact of recent sanitation programs. In choosing a physically representative variate for the water quality of the run-off, both concentrations and fluxes of pollutants must be taken into account. The importance of the climatic seasonal and hydrological factors associated with unstable event-related contributions of point and non-point pollution sources of the pollutants has lead us to simultaneously study water-discharge and pollutant flux time-series. The mass-discharge time-series are, in practice, far from being ideal for the application of classical trend analysis: they are relatively short and inaccurate: their distribution, orginating from mixed parent populations is very often highly skewed; they show a high level of serial dependence and the seasonal effects represent a large percentage of the variance, concealing possible long-term trends. Faced with the poor structure of these series which prohibits the use of statistical tests, experiments have been carried out with progressive-regressive inertial techniques, which imply the stationarity of water discharges. The double-mass technique was developed originally as a visual technique, to assess the homogeneity of precipitation records and was extended to study variations in sediment transport in modified watersheds. More recently confidence ‘rails’ and slope change detection have rendered its use more quantitative. Based on the same inertial principles, the Cumulative Sum (CUSUM) functions allow simultaneous evaluation of the covariability of the two series. An example involving weekly sampled nitrate concentrations and continuously monitored water discharges is developed. 相似文献
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Of the recent sauropsid skin appendage types, only feathers develop from a cylindrical epidermal invagination, the follicle, and show hierarchical branching. Fossilized integuments of Mesozoic diapsids have been interpreted as follicular and potential feather homologues, an idea particularly controversially discussed for the elongate dorsal skin projections of the small diapsid Longisquama insignis from the Triassic of Kyrgyzstan. Based on new finds and their comparison with the type material, we show that Longisquama's appendages consist of a single-branched internal frame enclosed by a flexible outer membrane. Not supporting a categorization either as feathers or as scales, our analysis demonstrates that the Longisquama appendages formed in a two-stage, feather-like developmental process, representing an unusual early example for the evolutionary plasticity of sauropsid integument. 相似文献
910.
Sauphanor B Franck P Lasnier T Toubon JF Beslay D Boivin T Bouvier JC Renou M 《Die Naturwissenschaften》2007,94(6):449-458
The behavioral and electroantennographic responses of Cydia pomonella (L.) to the ripe pear volatile ethyl (2E,4Z)-2,4-decadienoate (Et-E,Z-DD), were compared in insecticide-susceptible and -resistant populations originating from southern France. A dose–response
relationship to this kairomonal attractant was established for antennal activity and did not reveal differences between susceptible
and resistant strains. Conversely, males of the laboratory strains expressing metabolic [cytochrome P450-dependent mixed-function
oxidases (mfo)] or physiological (kdr-type mutation of the sodium-channel gene) resistance mechanisms exhibited a significantly
higher response to Et-E,Z-DD than those of the susceptible strain in a wind tunnel experiment. No response of the females to this kairomone could be
obtained in our wind-tunnel conditions. In apple orchards, mfo-resistant male moths were captured at significantly higher
rates in kairomone-baited traps than in traps baited with the sex pheromone of C. pomonella. Such a differential phenomenon was not verified for the kdr-resistant insects, which exhibited a similar response to both
the sex pheromone and the kairomonal attractant in apple orchards. Considering the widespread distribution of metabolic resistance
in European populations of C. pomonella and the enhanced behavioral response to Et-E,Z-DD in resistant moths, the development of control measures based on this kairomonal compound would be of great interest for
the management of insecticide resistance in this species. 相似文献