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31.
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Abstract

In this paper a two-photon Jaynes-Cummings model interacting with a Kerr-like medium is studied. It is assumed that the electromagnetic field is in different states such as coherent, squeezed vacuum and pair coherent, and that the atom is initially in the excited state. The temporal evolution of the population of the excited level, and the second-order coherence function are studied. The results obtained show that this system has some similarities with the two-mode Stark system. Two photon entanglement are analysed at different initial conditions.  相似文献   
33.
The feeding of young children is fundamentally a relational and multisystemic process. Successful treatment of clinically significant feeding problems involves careful assessment of the full range of influences on the feeding relationship and integrated treatment approaches. However, current diagnostic approaches to feeding disorders tend to be reductionistic, exclusively focused on the child as an individual, and overly concerned with exclusionary criteria. Criteria are proposed for "Feeding Disorder Between Parent and Child" that address these limitations and embrace the complexity of feeding problems. A multiaxial diagnosis that describes the child (including medical, developmental, and behavioral characteristics); the parent; the parent-child relationship; and the social and nutritional context of feeding will more accurately speak to treatment planning in this population. The proposed diagnostic criteria were developed and refined on the basis of the available literature and many years of treatment experience across the authors of this article. The proposed diagnosis will support the development and evaluation of treatment packages with components specifically targeted to issues of the child, parent, parent-child interaction, and the broader environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
The crystal structure of recombinant wild-type green fluorescent protein (GFP) has been solved to a resolution of 1.9 A by multiwavelength anomalous dispersion phasing methods. The protein is in the shape of a cylinder, comprising 11 strands of beta-sheet with an alpha-helix inside and short helical segments on the ends of the cylinder. This motif, with beta-structure on the outside and alpha-helix on the inside, represents a new protein fold, which we have named the beta-can. Two protomers pack closely together to form a dimer in the crystal. The fluorophores are protected inside the cylinders, and their structures are consistent with the formation of aromatic systems made up of Tyr66 with reduction of its C alpha-C beta bond coupled with cyclization of the neighboring glycine and serine residues. The environment inside the cylinder explains the effects of many existing mutants of GFP and suggests specific side chains that could be modified to change the spectral properties of GFP. Furthermore, the identification of the dimer contacts may allow mutagenic control of the state of assembly of the protein.  相似文献   
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Computed tomography (CT) was performed in 189 individuals: in 44 children of schizophrenic parents (high risk group, HRG), in 39 parents with schizophrenia or with schizophrenic disturbance, in 56 children with schizophrenia, in 50 children with consequences of early organic damages of central nervous system (mental retardation syndrome and generalized tic syndrome). The frequency of CT changes was equal in the mentioned groups but their character was quite different. The widening of brain's liquor system (89.7%), the signs of frontal and temporal atrophia (31%), foci of decreased density of cerebral brain's matter, closer in subcortical ganglia and periventricular zone, and different anomalies of brain were observed in HRG children.  相似文献   
37.
90 infants with intrauterine growth retardation (IGR) and 100 normal infants (control group) were followed up from 5 days till 3 years of life. In IGR infants there was a more frequent combination of several neurologic syndromes, an early manifestation of motor disorders (from the very moment of birth), a delay of neuro-psychic development (during the first year of life), a tendency to development of moderate hydrocephalus by the age of 6 months. Autonomic-visceral disorders in them were mostly characterized by the symptoms of abaissement, but not of irritation.  相似文献   
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Two noninvasive tests for assessing pancreatic exocrine function, the cholesteryl-[14C]octanoate breath test and the HPLCN-benzoyl-tyrosyl-p-aminobenzoic acid/p-aminosalicylic acid (NBT-PABA/PAS) test, were simultaneously performed in nine patients with pancreatic exocrine insufficiency due to chronic pancreatitis and in nine healthy volunteers. 14CO2 output in breath and plasma PABA concentration rose slowly in patients but increased rapidly in healthy subjects. The measurement time giving the best discrimination between both groups was 120 min for the cholesteryl-[14C]octanoate breath test and 90 min for the plasma PABA test. At these points, both single-sample tests had essentially identical diagnostic sensitivity. The diagnostic sensitivities of the two single-sample tests were equal to that of the cumulative 6-h urinary PABA recovery and the cumulative 6-h urinary PABA/PAS ratio. We conclude that, for both the cholesteryl-[14C]octanoate breath test and the plasma PABA test, a single test sample is sufficient for rapid detection of impaired exocrine pancreatic function.  相似文献   
40.
Marrow stromal layers were used to investigate the potential role of negative regulators produced by the marrow microenvironment as one potential cause of hematopoietic suppression after chemotherapy and cytokines. Stromal layers were established from marrow of normal or prechemotherapy donors and breast cancer patients after hematological recovery from one cycle of 5-fluorouracil, leucovorin, doxorubicin, and cyclophosphamide and GM-CSF or PIXY321 (GM-CSF/IL-3 fusion protein). Normal donor CD34+ cells were placed in contact with stromal layers, and the number of colony-forming units for granulocytes and macrophages (CFU-GM) was determined. There were 25-79% fewer CFU-GM in post-chemotherapy stromal layer cocultures than in no chemotherapy cocultures. With neutralizing antibody to TNF-alpha the number of CFU-GM in no chemotherapy and post-chemotherapy stromal cocultures was, respectively, 96 +/- 7% (n = 5) and 142 +/- 8% (n = 5) of the number with no antibody treatment. PIXY321 and GM-CSF pretreated stromal layers also suppressed production of CFU-GM. Anti-TNF-alpha promoted an increase in CFU-GM numbers from GM-CSF, but not PIXY321, pretreated stromal cocultures. The results demonstrate that post-chemotherapy marrow stromal layers were deficient in supporting in vitro hematopoiesis and suggest that negative regulators induced by chemotherapy and cytokines may be one cause for this defect.  相似文献   
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