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Pax genes are expressed in specific patterns in the nervous system during development and in the adult. Recent findings suggest a link between the expression of Pax-2 and axonal guidance. Mice with a targeted deletion of Pax-2 are an excellent tool for studying axonal pathfinding at the molecular level, especially with respect to the optic chiasm. The date reviewed here suggest that Pax-2 regulates the expression of surface molecules involved in contact attraction and that the mutual regulation of the expression of Pax-2 and the Sonic hedgehog gene is of importance in the formation of the chiasm region. 相似文献
3.
AL Jensen MK Thomsen H Aaes M Andreasen J S?ndergaard 《Canadian Metallurgical Quarterly》1993,37(3-4):329-336
Growth hormone (GH) has recently been shown to affect polymorphonuclear neutrophil granulocyte (PMN) function and to be secreted by mononuclear cells, indicating that the hormone may be active in an immunophysiologic network, acting as an endo- or paracrine priming agent. The purpose of the present study was to evaluate the chemotactic responsiveness of canine peripheral PMN in a dog with acromegaly, caused by spontaneous, progesterone-induced hypersecretion of GH and, secondary to this, a seven-fold increase in insulin-like growth factor I (IGF-I). The chemotactic responsiveness towards zymosan-activated serum (ZAS) and leukotriene B4 (LTB4) was evaluated at a time when the dog suffered from acromegaly and again 57 days after corrective surgery (ovariohysterectomy). The experiments showed that PMN from the patient exhibited enhanced chemotactic migration that appeared to be associated with the hypersomatotropic condition as judged from the reversibility of the phenomenon. The glucose intolerance and elevated serum alkaline phosphatase that were observed in the acromegalic dog were also shown to be reversible following surgery. 相似文献
4.
BB Horswell CL Castiglione AE Poole LA Assael 《Canadian Metallurgical Quarterly》1993,51(2):145-9; discussion 149-50
The double-reversing Z-plasty of Furlow for closure of the soft palate was used in 34 children with various types of cleft palate. Mean age at repair was 12.8 months. Intraoperative experience was favorable, with acceptable operating time and blood loss. Length of hospitalization averaged 1.9 days. Postoperatively, two children experienced temporary stridor, which resolved within 24 to 48 hours. One child had dehiscence of the hard palate (Von Lagenbeck repair) 4 weeks postoperatively, and three children developed small oronasal fistulae. Early speech evaluation demonstrated adequate soft palate mobility in 33 of 34 patients, with observable velopharyngeal function. Twelve children had mild velar compromise, with eight exhibiting slight nasal air escape. 相似文献
5.
RJ Jensen 《Canadian Metallurgical Quarterly》1996,13(4):705-719
Previous studies have shown that directionally selective (DS) retinal ganglion cells cannot only discriminate the direction of a moving object but they can also discriminate the sequence of two flashes of light at neighboring locations in the visual field: that is, the cells elicit a DS response to both real and apparent motion. This study examines whether a DS response can be elicited in DS ganglion cells by simply stimulating two neighboring areas of the retina with high external K+. Extracellular recordings were made from ON-OFF DS ganglion cells in superfused rabbit retinas, and the responses of these cells to focal applications of 100 mM KCl to the vitreal surface of the retina were measured. All cells produced a burst of spikes (typically lasting 50-200 ms) when a short pulse (10-50 ms duration) of KCl was ejected from the tip of a micropipette that was placed within the cell's receptive field. When KCl was ejected successively from the tips of two micropipettes that were aligned along the preferred-null axis of a cell, sequence-dependent responses were observed. The response to the second micropipette was suppressed when mimicking motion in the cell's null direction, whereas an enhancement during apparent motion in the opposite direction frequently occurred. Sequence discrimination in these cells was eliminated by the GABA antagonist picrotoxin and by the Ca(2+)-channel blocker omega-conotoxin MVIIC, two drugs that are known to abolish directional selectivity in these ganglion cells. The spatiotemporal properties of the K(+)-evoked sequence-dependent responses are described and compared with previous findings on apparent motion responses of ON-OFF DS ganglion cells. 相似文献
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Responds to the comments by L. T. Hoshmand (see record 2003-08988-012) and J. Aros (see record 2003-08988-013) on the article by J. Arnett (see record 2002-18352-003) regarding the psychology of globalization. In this response, Arnett discusses the moral implications of globalization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
AS Astapchik EP Podvoisky IS Chebotko BM Khusid AG Merzhanov BB Khina 《Canadian Metallurgical Quarterly》1993,47(1):319-326
The labile protons of two 32-base-pair, four-arm models of immobile Holliday junctions have been studied by two-dimensional 1H nuclear magnetic resonance (NMR) spectroscopy. Overlap of resonances in the imino-imino region of two-dimensional nuclear Overhauser enhancement (NOE) spectra necessitates the use of a multi-pathway approach for obtaining sequence-specific assignments wherein all possible NOE connectivities to the labile protons are utilized, including those from the 2H of adenine, 5CH3 of thymine, and 5H of cytosine. Resonance assignments are obtained for all slowly exchanging imino and cytosine amino protons. Base-pairing up to and including the junction point is found in all four arms of both Holliday junctions. Several cross-arm NOE connectivities are identified and can be used to infer the geometry of the helical stacking domains. The two Holliday junctions studied, which differ only by the exchange of two base pairs at the branch point, appear to have opposite arm stacking geometries. These assignments form an important part of the critical background for detailed NMR analysis of Holliday junction structure and dynamics. 相似文献
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A case-mix classification system for medical rehabilitation 总被引:2,自引:0,他引:2
MG Stineman JJ Escarce JE Goin BB Hamilton CV Granger SV Williams 《Canadian Metallurgical Quarterly》1994,32(4):366-379
Dissatisfaction with Medicare's current system of paying for rehabilitation care has led to proposals for a rehabilitation prospective payment system, but first a classification system for rehabilitation patients must be created. Data for 36,980 patients admitted to and discharged from 125 rehabilitation facilities between January 1, 1990, and April 19, 1991, were provided by the Uniform Data System for Medical Rehabilitation. Classification rules were formed using clinical judgment and a recursive partitioning algorithm. The Functional Independence Measure version of the Function Related Groups (FIM-FRGs) uses four predictor variables: diagnosis leading to disability, admission scores for motor and cognitive functional status subscales as measured by the Functional Independence Measure, and patient age. The system contains 53 FRGs and explains 31.3% of the variance in the natural logarithm length of stay for patients in a validation sample. The FIM-FRG classification system is conceptually simple and stable when tested on a validation sample. The classification system contains a manageable number of groups, and may represent a solution to the problem of classifying medical rehabilitation patients for payment, facility planning, and research on the outcomes, quality, and cost of rehabilitation. 相似文献