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371.
Summary The practice of the transcendental meditation technique in subjects eliciting this state regularly for 3–5 years is correlated with acute decline of adrenocortical activity not associated with sleep during the practice. 相似文献
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Numerical state space models are efficiently implemented for the estimation of the underlying level and trend of a time series. The model specification is chosen so that the estimation is insensitive to outliers yet adapts rapidly to step changes in level. An example illustrates, by means of projection plots, how at times of uncertainty in the evolution of the series the inferred distribution of level and trend may be multi-modal. 相似文献
374.
M Marra T Kucaba M Sekhon L Hillier R Martienssen A Chinwalla J Crockett J Fedele H Grover C Gund W R McCombie K McDonald J McPherson N Mudd L Parnell J Schein R Seim P Shelby R Waterston R Wilson 《Nature genetics》1999,22(3):265-270
Arabidopsis thaliana has emerged as a model system for studies of plant genetics and development, and its genome has been targeted for sequencing by an international consortium (the Arabidopsis Genome Initiative; http://genome-www. stanford.edu/Arabidopsis/agi.html). To support the genome-sequencing effort, we fingerprinted more than 20,000 BACs (ref. 2) from two high-quality publicly available libraries, generating an estimated 17-fold redundant coverage of the genome, and used the fingerprints to nucleate assembly of the data by computer. Subsequent manual revision of the assemblies resulted in the incorporation of 19,661 fingerprinted BACs into 169 ordered sets of overlapping clones ('contigs'), each containing at least 3 clones. These contigs are ideal for parallel selection of BACs for large-scale sequencing and have supported the generation of more than 5.8 Mb of finished genome sequence submitted to GenBank; analysis of the sequence has confirmed the integrity of contigs constructed using this fingerprint data. Placement of contigs onto chromosomes can now be performed, and is being pursued by groups involved in both sequencing and positional cloning studies. To our knowledge, these data provide the first example of whole-genome random BAC fingerprint analysis of a eucaryote, and have provided a model essential to efforts aimed at generating similar databases of fingerprint contigs to support sequencing of other complex genomes, including that of human. 相似文献
375.
J. A. Yager D. B. Hunter M. R. Wilson O. B. Allen 《Cellular and molecular life sciences : CMLS》1988,44(1):79-81
Summary Unique hypertrophic apocrine sweat glands are described in the neck, perineal and inguinal skin of mink kits. These glands enlarge after birth, only to regress rapidly and become vestigal by weaning. No similar phenomenon has been recognized before in mammals. Behavioral studies indicate a possible role for the glandular secretion in maternal recognition of the young. 相似文献
376.
Transfer of parental strain T lymphocytes into F1 hybrid rats differing with respect to gene products of the major histocompatibility complex (MHC) causes a graft-versus-host (GvH) reaction. This reaction results from recognition of host allogeneic MHC gene products by specific clones of donor T cells. When given systemically in sufficient numbers, these donor T cells cause a progressive, generally fatal wasting syndrome, an early feature of which includes extensive splenomegaly. A more local, non-fatal GvH reaction, marked by extensive enlargement of the draining lymph nodes, ensues when donor T cells are administered via the footpad. Here, we demonstrate that cells derived from the enlarged draining lymph nodes of A/B F1 animals undergoing local GvH disease caused by donor A T cells contain a subpopulation of host-derived killer T-cell precursors which can be activated to lyse specific blast cells, derived from mixed lymphocyte culture (MLC), reactive to host MHCb alloantigens. These 'anti-idiotypic' cytolytic T cells lyse A anti-MHCb MLC blasts, and also, they lyse anti-MHCb MLC blasts from MHC different, third party rat strains. 相似文献
377.
Reduction of transmitter release by D-tubocurarine 总被引:7,自引:0,他引:7
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This paper reviews earlier work on the validation of mathematical models and modeling within Decision Support Systems (DSS), in particular where the DSS were developed to support operations management. The authors found that little validation was carried out in practice. With this work as a base, reasons for the paucity of validation are advanced and comparisons with DSS developed to support marketing management are made. The case for a more appropriate methodology of validation is advanced. 相似文献