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Validity of the examination method of occlusal contact pattern relating to mandibular position

JOURNAL OF DENTISTRY 2000年第1期28卷 23-29页

作者： Ogawa, T Ogimoto, T Koyano, K Kyushu Univ Fac Dent Dept Removable Prosthodont Fukuoka 812 Japan

Objective: This study was based on the hypothesis that conflicting findings and inconclusive consensus regarding the role of occlusal factors in the masticatory system are due to the variations in the definitions and methods used to describe and examine the occlusal factors. The object of this study was to determine whether contact patterns during lateral movement vary with mandibular positions and whether the contact pattern in lateral positions close to the maximum intercuspation has characteristics distinct from those in an edge-to-edge position. Methods: Occlusal contacts of 86 young adults were examined using shim stock in regulated lateral positions: 0.5, 1, 2 and 3 mm from the maximum intercuspation, where the 0.5, 1 and 2 mm positions were defined as lateral positions close to the maximum intercuspation and the 3 mm position as an edge-to-edge position. Results: The occlusal contact pattern in the 0.5 mm position showed a marked prevalence of posterior tooth contacts on the working and the non-working sides, compared with the 1, 2 and 3 mm positions. The occlusal contact pattern in the 3 mm position predicted the presence or absence of the occlusal contact in the 1 and 2 mm positions (sensitivity > 0.7) but not in the 0.5 mm position (sensitivity < 0.6). Conclusion: The occlusal contact patterns during lateral movement varied greatly with mandibular positions. The examination method of the occlusal contact pattern in one unregulated position will be invalid. It is necessary to distinguish the occlusal contact patterns between a position close to the maximum intercuspation and an edge-to-edge position when investigating its role in the masticatory system and in oral disease. (C) 1999 Elsevier Science Ltd. All rights reserved.

关键词： occulusion contact guidance lateral excursion occlusion

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Expression and regulation of chicken fibroblast growth factor homologous factor (FHF)-4 at the base of the developing limbs

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MECHANISMS OF DEVELOPMENT 2000年第1-2期95卷 101-112页

作者： Muñoz-Sanjuán, I Fallon, JF Nathans, J Johns Hopkins Univ Sch Med Dept Mol Biol & Genet Baltimore MD 21205 USA Univ Wisconsin Dept Anat Madison WI 53706 USA Johns Hopkins Univ Sch Med Dept Ophthalmol Baltimore MD 21205 USA Johns Hopkins Univ Sch Med Dept Neurosci Baltimore MD 21205 USA Johns Hopkins Univ Sch Med Howard Hughes Med Inst Baltimore MD 21205 USA

Fibroblast growth factor homologous factors (FHFs) have been implicated in limb and nervous system development. In this paper we describe the expression of the cFHF-4 gene during early chicken development, cFHF-4 is expressed in the paraxial mesoderm, lateral ridge, and, most prominently, in the posterior-dorsal side of the base of each limb bud. The expression pattern of cFHF-4 at the base of the limbs is not altered by tissue grafts containing the zone of polarizing activity (ZPA), by implants of Shh-expressing cells, or by implants of beads containing retinoic acid, nor does it depend on the distal growth of the limb as it is not altered in limb buds that are surgically truncated. In three chicken mutants affecting limb patterning - talpid(2), limbless, and wingless - altered patterns of cFHF-4 expression are correlated with abnormal nerve plexus formation and altered patterns of limb bud innervation. Similarly, ectopic expression of cFHF-4 is correlated with a local induction of limb-like innervation patterns when beads containing FGF-2 are implanted in the flank. In these experiments, both ectopic innervation and ectopic expression of cFHF-4 in the flank were observed regardless of the size of the FGF-2-induced outgrowths. By contrast, ectopic expression of Shh and HoxD13 are seen only in the larger FGF-2-induced outgrowths. Taken together, these data suggest that cFHF-4 regulates or is coregulated with early events related to innervation at the base of the limbs. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.

关键词： fibroblast growth factor homologous factors FGF-2 talpid(2) limbless chicken mutant wingless chicken mutant plexus formation axonal guidance

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Ordered networks of rat hippocampal neurons attached to silicon oxide surfaces

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JOURNAL OF NEUROSCIENCE METHODS 2000年第1期104卷 65-75页

作者： Scholl, M Sprössler, C Denyer, M Krause, M Nakajima, K Maelicke, A Knoll, W Offenhäusser, A Max Planck Inst Polymer Res D-55128 Mainz Germany Univ Mainz Inst Physiol Chem & Pathobiochem D-55099 Mainz Germany Inst Phys & Chem Res Wako Saitama 3510198 Japan

The control of neuronal cell position and outgrowth is of fundamental interest in the development of applications ranging from cellular biosensors to tissue engineering. We have produced rectangular networks of functional rat hippocampal neurons on silicon oxide surfaces. Attachment and network formation of neurons was guided by a geometrical grid pattern of the adhesion peptide PA22-2 which matches in sequence a part of the A-chain of laminin. PA22-2 was applied by contact printing onto the functionalised silicon oxide surface and was immobilised by hetero-bifunctional cross-linking with sulfo-GMBS. Geometric pattern matching was achieved by microcontact printing using a polydimethylsiloxane (PDMS) stamp. In this way the produced grid pattern ranged from 3 to 20 mum in line width and from 50 to 100 mum in line distances. As shown by atomic force microscopy (AFM), line widths and line distances of the peptide pattern differ less than 0.5 mum from the used PDMS stamp. The height of the layer of immobilised PA22-2 was approximately 3.5 nm implying the layer to be monomolecular. Immobilised PA22-2 was capable of binding anti-PA22-2 antibodies indicating that the function of the peptide was not compromised by immobilisation. Rat hippocampal neurons, cultured at low density in serum-free medium, were applied to the growth matrix of PA22-2-coated substrates and, within 1-3 h of culture, formed a network-like pattern that mure or less matched the printed grid. Reliability and reproducibility of neuronal network formation depended on the geometry, line width and node diameter of the grid pattern. The immobilised neurons showed resting membrane potentials comparable with controls and, already after 1 day of culture, were capable of eliciting action potentials. The suitability of the immobilised neurons fur the study of man-made neural networks and for multi-site recordings from a functional neuronal network is discussed. (C) 2000 Elsevier Science B.V. All rights reserved.

关键词： microcontact printing guidance pattern cell adhesion hippocampal neurons

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CT-guided cutting needle biopsy of lung lesions - Safety and efficacy of an out-patient service

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CLINICAL RADIOLOGY 2000年第12期55卷 964-969页

作者： Charig, MJ Phillips, AJ Wexham Pk Hosp Dept Radiol Slough SL2 4HL Berks England

AIM: To determine the safety and efficacy of CT-guided cutting needle biopsy of lung lesions as an out-patient procedure. MATERIALS AND METHODS: A total of 185 consecutive biopsies were performed under CT guidance on 183 patients between January 1991 and December 1998 using 20-gauge (n = 33), 18-gauge (n = 151) or 14-gauge (n = 1) core biopsy needles. A chest radiograph was taken after observation in the Radiology department for I h and asymptomatic patients were discharged. RESULTS: The histology was malignant in 150 biopsies (81.1%) and benign in 23 (12.4%) with 12 false-negative results (6.5%);there were no false-positive results, The sensitivity was 92.6%;specificity 100%;negative predictive value 65.7%;and overall accuracy 93.5%. Pneumothoraces occurred in 48 patients (25.9%);one required aspiration only and four required insertion of an intercostal drain. One patient developed a pneumothorax after discharge, Small haemoptyses occurred in 13 patients without pneumothorax (7.0%), one of whom was admitted, In-patient treatment was required in 10 patients (5.4%). CONCLUSION: Computed tomography-guided cutting needle biopsy of pulmonary lesions is a safe technique with a diagnostic accuracy and complication rate comparable to reported figures for fine needle aspiration biopsy. It can be safely performed on an out-patient basis, Charig, M. J., Phillips, A. J. (2000). Clinical Radiology 55, 964-969. (C) 2000 The Royal College of Radiologists.

关键词： lung biopsy computed tomography guidance pneumothorax

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CT-guided transthoracic needle biopsy of pulmonary nodules smaller than 20 mm: Results with an automated 20-gauge coaxial cutting needle

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CLINICAL RADIOLOGY 2000年第4期55卷 281-287页

作者： Laurent, F Latrabe, V Vergier, B Montaudon, M Vernejoux, JM Dubrez, J Univ Bordeaux 2 CHU Bordeaux Hosp Haut Leveque Dept Radiol F-33604 Pessac France Univ Bordeaux 2 Dept Pathol Hosp Haut Leveque F-33604 Pessac France Univ Bordeaux 2 Dept Pneumol Hosp Haut Leveque F-33604 Pessac France Univ Bordeaux 2 Dept Thorac Surg Hosp Haut Leveque F-33604 Pessac France

AIMS: To evaluate the efficacy and the complication rate of CT-guided percutaneous lung biopsy of pulmonary nodules smaller than 20 mm in diameter using a 20-gauge coaxial automated biopsy device. MATERIAL AND METHODS: A prospective study was undertaken of 200 patients who underwent 202 consecutive biopsies of pulmonary nodules, performed with a single type of automated biopsy device. Sixty-seven biopsies of nodules smaller than 20 mm in diameter were performed in 66 patients (group A). One hundred and thirty-five biopsies of lesions of 20 mm or greater in size were performed in 134 patients (group B). Patient characteristics, lesion and procedure variables, the accuracy and complication rates were compared. RESULTS: In group A, the final diagnosis of the nodules was malignant in 47 and benign in 19 cases (prevalence of malignancy 71.2%). In group B, there were 111 malignant and 21 benign diagnoses (prevalence of malignancy 82.2%). In group A, the sensitivity and specificity for a diagnosis of malignancy were 89.5 and 100%, respectively (positive predictive value 100%, negative predictive value 76%). A specific diagnosis of benignity was obtained in nine out of 19 (47%) biopsies. The pneumothorax rate was 15% (10 patients) of which two (3%) required drainage. CT signs thought to reflect alveolar haemorrhage were noted in 28 (43%) and haemoptysis occurred in five patients (5.9%). In group B, the sensitivity and specificity for a diagnosis of malignancy were 95.5% and 100%, respectively (positive predictive value 100%, negative predictive value 82.7%). A specific diagnosis of benignity was made in 14 cases (58.3%). Complications included pneumothoraces in 22 cases (16.2%) requiring drainage in one (0.7%). Presumed alveolar haemorrhage was recorded in 19 cases (14.1%) and haemoptysis occurred in seven (5.2%). There were no significant differences between group A and group B, except for alveolar haemorrhage (P < 0.001). CONCLUSION: The accuracy and complication rate of

关键词： biopsy technology computed tomography guidance interventional procedures complications lung biopsy neoplasm diagnosis

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The generation of localized calcium rises mediated by cell adhesion molecules and their role in neuronal growth cone motility

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Molecular Cell Biology Research Communications 2000年第5期3卷 255-263页

作者： Dunican, Dara J. Doherty, Patrick Molecular Neurobiology Group Guy's Campus Kings College London London SE1 9RT London Bridge United Kingdom

Neurite growth and guidance depends on the transduction of extracellular guidance cues into motile responses by the sensory apparatus at the tip of the neurite, the growth cone. Contact of the growth cone with extracellular ligands leads to the cytoskeletal reorganisation required for changes in rate of motility and direction of outgrowth. Differential adhesion mediated by cell adhesion molecules and signal transduction pathways mediated by growth cone receptors were once seen as separate but cooperative events in controlling growth cone motility. However, recent findings suggest that cell adhesion molecules can activate novel signalling pathways in the growth cone by the recruitment of fibroblast growth factor receptors leading to neurite outgrowth. This Review focuses on work by various laboratories centering on the intracellular consequences of the cell adhesion molecule-mediated activation of the fibroblast growth factor receptor. These include activation of a lipase cascade including phospholipase C and diacylglycerol lipase and culminating in the release of arachidonic acid. This release of arachidonic acid is proposed to activate the transient opening of voltage dependent ion-channels leading to localised rises in growth Ca²⁺. Recent findings demonstrating this previously undetectable rise in Ca²⁺ in the growth cone are discussed in light of the proposed roles and mechanisms of Ca²⁺ in controlling neurite outgrowth. The Ca²⁺ rises are thought to induce the activation of GAP43 and Ca²⁺/calmodulin-dependent kinase II, molecules implicated in the modulation of cytoskeletal remodelling. The evidence that this pathway may be involved in the guidance of retinal ganglion cells is evaluated. (C) 2000 Academic Press.

关键词： Arachidonic acid Calcineurin CaM kinase DAG lipase FGFR Filopodia GAP-43 Growth cone guidance L1 N-cadherin NCAM Neurite outgrowth PLC

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The aptitude-achievement function: An aid for allocating educational resources, with an advanced placement example

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EDUCATIONAL PSYCHOLOGY REVIEW 2000年第2期12卷 201-228页

作者： Lichten, W Wainer, H Yale Univ Inst Social & Policy Studies New Haven CT 06520 USA

We fit a functional relationship between aptitude and achievement test scores and show how to use it to allocate educational resources. As an example we use the PSAT-Mathematics test to predict performance on the College Board's Advanced Placement Test in calculus, as a guide to student and school participation, for school or system assessment, and to project future nationwide expansion. In addition to the PSAT-AP test score relations, we consider the distribution of student ability, school policies of student selection and recruitment, and teacher skill in presenting the material and in motivating students. This overall result provides an indication of just how remarkable was Jaime Escalante's accomplishment in Los Angeles's Garfield High School. We find little evidence for differences in educational quality between such diverse schools as in the inner city of Detroit and the affluent suburb of La Canada, California. We comment briefly on the role of the AP in international assessments.

关键词： advanced Placement calculus Jaime Escalante PSAT Detroit Garfield High School logistic fitting functions guidance assessment international education achievement tests

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Promoting social skills in young children

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Early Childhood Education Journal 2000年第2期28卷 105-110页

作者： Lawhon, Tommie Lawhon, David C. College of Education University of North Texas United States University of Texas Dallas TX United States College of Education UNT Box 311337 University of North Texas Denton TX 76203-1337 United States

The literature reflects that numerous factors impact a young child's ability to have playmates and develop friendships. This in turn can influence health, happiness, and stability throughout life. Social relationships may be enhanced through a youngster's efforts and those of caring adults, especially teachers, parents, and other caregivers. Two checklists are provided, one to assist when observing and recording a child's personal behaviors and another to aid adults with the self-assessment of their child guidance techniques. These results are beneficial to those who teach, guide, train, and provide other essential experiences for children. © 2000 Human Sciences Press, Inc.

关键词： Friendships guidance Socialization Young children

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Video-based sensor for tracking 3-dimensional targets

Video-based sensor for tracking 3-dimensional targets

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Conference on Atmospheric Propagation, Adaptive Systems, and Laser Radar Technology for Remote Sensing

作者： Howard, RT Book, ML Bryan, TC NASA George C Marshall Space Flight Ctr Huntsville AL 35812 USA

ISBN: (纸本)0819438235

The National Aeronautics and Space Administration's (NASA's) Marshall Space Plight Center (MSFC) has been developing and testing video-based sensors for automated spacecraft guidance for several years. The video sensor currently under development is to have a tracking rate of 50 Hz while delivering full 3-dimensional relative information (X, Y, Z, Pitch, Yaw, and Roll.) Prior systems have been developed and tested in both open-loop and closed-loop simulations. The prototype Video guidance Sensor (VGS) was built for a flight experiment and performed well on two separate Space Shuttle flights. The VGS uses two wavelengths of light to illuminate a target that has a pattern of filtered retro-reflectors. The filters pass only one wavelength of light and absorb the other. Two fast, successive pictures are taken of the target, each picture illuminated by a different wavelength. When the background picture is subtracted from the foreground, a high signal to noise ratio is achieved, and the target spots are easy to track. The next generation VGS will be using a CMOS imaging chip for higher-speed target tracking and a Texas Instruments DSP for higher-speed image processing. The system is being designed to have lower weight and power requirements than the previous generation, and it will be suitable for other applications.

关键词： video sensor guidance AR&C AR&D automated docking automatic docking

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A new computational approach to real-time trajectory generation for constrained mechanical systems

A new computational approach to real-time trajectory generat...

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39th IEEE Conference on Decision and Control

作者： Milam, MB Mushambi, K Murray, RM CALTECH Pasadena CA 91125 USA

ISBN: (纸本)0780366387

Preliminary results of a new computational approach to generate aggressive trajectories in real-time for constrained mechanical systems are presented. The algorithm is based on a combination of nonlinear control theory, spline theory, and sequential quadratic programming. It is demonstrated that read-time trajectory generation for constrained mechanical systems is possible by mapping the problem to one of finding trajectory curves in a lower dimensional space. Performance of the algorithm is compared with existing optimal trajectory generation techniques. Numerical results are reported using the NTG software package.

关键词： real-time optimization nonlinear control design optimal control constrained trajectory generation guidance

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