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Describes the Blind Learning Aptitude Test (BLAT) and presents age norm data. Use of BLAT (T. E. Newland, 1977) in rehabilitation assessment with regard to academic learning potential is considered. The high correlation of BLAT performance with measured educational achievement and the cultural neutrality of BLAT indicate its usefulness in assessing basic cognitive learning potential of rehabilitation clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The capabilities of 1alpha, 25-dihydroxyvitamin D3 (1,25(OH)2D3), and two novel vitamin D analogues, EB1089 and KH1060, to induce the differentiation of two established leukaemia cell lines, U937 and HL-60, were assessed alone or in combination with the retinoid compounds, 9-cis retinoic acid (9-cis RA) and all-trans retinoic acid (ATRA). The vitamin D derivatives acted to increase the differentiation of U937 and HL-60 cell cultures in a dose-dependent manner, as determined by nitroblue tetrazolium (NBT) reduction, with EB1089 and KH1060 being more effective than the native hormone. As an additional index of leukaemic cell differentiation, induction of expression of the phenotypic cell surface antigen, CD14, and the beta2-integrins, CD11b and CD18 by the vitamin D and retinoid compounds were monitored using fluorescence activated cell sorting (FACS) analyses. Following 96-hr treatment of U937 and HL-60 cells with 5 x 10(-10) M of the vitamin D derivatives, a striking increase in CD14 antigen expression was apparent, indicating the promotion by these compounds of a monocyte/macrophage lineage of cells. CD11b and CD18 antigen expression were also raised above control levels. In contrast, both retinoid compounds used at the higher concentration of 1 x 10(-8) M were not effective inducers of CD14 antigen expression. However, CD11b and CD18 were both readily increased in U937 and HL-60 cell cultures. Treatment of U937 cell cultures with the vitamin D compounds and the retinoids resulted in cooperative effects on induction of differentiation, with correlation by both NBT reduction and FACS analyses of CD14 antigen expression. The presence of 9-cis RA or ATRA appeared to contribute to the further increase of CD14 in these cells. HL-60 cell cotreatment with these compounds also displayed enhanced cooperative effects in phagocytic function by NBT reduction. However, analysis of CD14 revealed a dramatic diminution in HL-60 cells treated with the combinations of the vitamin D derivatives and the retinoids. Assessment of HL-60 cell morphology treated with these combinations demonstrated the presence of a mixed population of monocytes and granulocytes. CD11b and CD18 antigen expression was also enhanced in both cell lines with cotreatment. The ability of EB1089 and KH1060 to induce leukaemic cell differentiation may provide an additional option for therapeutic use alone or together with other differentiation agents such as 9-cis RA or ATRA.  相似文献   
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Despite the demonstrated beneficial effects of methylphenidate and d-amphetamine for the treatment of attention-deficit hyperactivity disorder (ADHD), the discriminative and subjective effects of these compounds in children are not well understood. This study was designed to characterize such effects in children diagnosed with ADHD. In a series of 3 experiments, 17 children were examined to determine whether methylphenidate (n = 12) and d-amphetamine (n = 5) could be reliably discriminated at doses typically used in clinical practice. Under some conditions (e.g., when they were instructed to attend to the drug effects or when a wide range of doses was used), children discriminated methylphenidate (5.0-30.0 mg) from placebo. Children tested under a range of doses of d-amphetamine (2.5-20.0 mg) were unable to discriminate this drug from placebo reliably. Neither methylphenidate nor d-amphetamine produced reliable participant-rated effects.  相似文献   
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A general dynamical model of a vertical slender structure with damping is derived, and it is shown how this model may be used to calculate the frequencies, logarithmic decrements and mode shapes for the structure's free vibration. The model is applied to the analysis of a chimney mounted on a resilient seating to increase its damping, and typical results are given.  相似文献   
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1,25-dihydroxyvitamin D3 (1,25(OH)2D3), gamma interferon (IFN-gamma) and granulocyte-macrophage colony-stimulating factor (GM-CSF) can regulate monocyte maturation and activation. Using the human monocytoid cell line U937, we have shown that these agents increase surface tumor necrosis factor (TNF) expression without directly affecting TNF release. GM-CSF and IFN-gamma combined with 1,25(OH)2D3 increased cellular TNF secretion to levels not seen with these agents alone. Ability to express and secrete TNF in part depended on degree of monocytic maturation. The combination of 1,25(OH)2D3 and GM-CSF, however, facilitated lipopolysaccharide (LPS)-mediated release of surface TNF from U937 cells, an effect that was temporally independent of maximal maturation. 1,25(OH)2D3 plus IFN-gamma was less effective than 1,25(OH)2D3 plus GM-CSF at facilitating TNF secretion. We postulate that 1,25(OH)2D3 and GM-CSF are required together to prime a specific mechanism, probably a protease, which cleaves TNF from the surface of monocytic cells. This protease, once primed, can be activated by a secondary stimulus such as LPS.  相似文献   
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This paper shows that there are three main categories of factors that make the optimum mechanical design of micro-systems different from macro-systems: scale effects, a limited range of materials, and a limited range of production processes. The combined effect of these factors can make the optimum configuration of a micro-system potentially very different from that of the same system on a macro-scale. In particular, the use of flexible elements for hinges is much more feasible and desirable on a micro-scale.Notation a acceleration (m/s2) - A cross-sectional area (m2) - B magnetic flux [wb/m2] - b width [m] - C constant - d depth [m] - D drag [N] - E Young's modulus [N/m2] - E*= - f resonant frequency [Hz] - F D drive force [N] - F E electrostatic pulling force [N] - F emmisivity function - F G geometric view factor - g gravitational constant [m/s2] - h c convention heat transfer coefficient [W/m2K] - h height [m] - i current [A] - I A second moment of area [m4] - I I moment of inertia [kg m2] - J polar second moment of area [m4] - k stiffness [N/m] - K thermal conductivity [W/m K] - l length [m] - m mass [kg] - M moment [N m] - P load [N] - P H Hertz contact pressure [N/m2] - P C cylinder pressure [N/m2] - q heat transfer rate [W] - R, r radius [m] - Re Reynolds number - T, t temperature [K] - T A atomic friction torque [N m] - T D drive torque [N m] - T F Coulomb friction torque [N m] - T I inertial resistive torque [N m] - u velocity [m/s] - mean velocity [m/s] - V volume [m3] - V e voltage [V] - x distance between electrodes [m] - y maximum distance to neutral axis [m] - angular acceleration [rad/s2] - d thermal diffusivity [1/K] - rolling friction factor - P pressure difference [N/m2] - 0 dialectric constant [F/m] - strain - dynamic viscosity [Pa s] - scale factor - S coefficient of sliding friction - R coefficient of rolling friction - 1, 2 Poisson's ratio - density (kg/m3) - temperature rise [°C] - B bending stress [N/m2] - y yield strength [N/m2] - shear stress [N/m2] - reliability constant  相似文献   
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To examine the relationship between apolipoprotein E (apoE) phenotype and life span, we measured the frequently of the apoE phenotype and allele in 54 Japanese centenarians who lived in the Tokyo metropolitan area in 1994, 1995, and 1996. The control group consisted of 973 subjects, 883 healthy volunteers who were described previously and 90 healthy people who came to the Keio health consulting center. The apoE phenotypes in the centenarians was 2 E2/E2 (3.7%), 5 E2/E3 (9.3%), 38 E3/E3 (70.4%), and 9 3E/E4 (16.7%). No other phenotype was observed. In the control group, the phenotypes were 2 E2/E2 (0.2%), 57 E2/E3 (5.9%) 712 E3/E3 (73.2%), and 179 E3/E4 (18.4%). The frequency of E2 was higher in the centenarians. The frequencies of the apoE allele in the centenarians and the control subjects were epsilon 2 8.3% vs. 3.5%, epsilon 3 83.3% vs. 85.4%, and epsilon 4 8.3% vs. 10.9%. The frequency of the apoE allele differed significantly between centenarians and control subjects (chi 2 = 6.84, p = 0.033). Levels of serum cholesterol and apolipoprotein B were significantly lower in the E2/E2 + E2/E3 centenarians. Studies of the frequency of the apoE allele in Japanese, French, and Finnish subjects showed that epsilon 2 is more frequent and epsilon 4 is less frequent in centenarians. These data show the apoE phenotype may affect life span: epsilon 2 is positively and epsilon 4 is negatively associated with longevity.  相似文献   
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BACKGROUND: The efficacy of omeprazole, 20 mg once daily, in the treatment of reflux oesophagitis and the therapeutic advantages over the histamine H2 receptor antagonists are well documented. This study assessed 20 mg omeprazole daily (OM20), 10 mg omeprazole daily (OM10), and 150 mg ranitidine (RAN) twice daily for symptom relief in gastro-oesophageal reflux disease (GORD). METHODS: Patients (n = 994) presenting with heartburn to their general practitioner underwent endoscopy to exclude peptic ulcer disease and were randomized into a UK, multicentre, parallel-group, double-blind comparison of the three treatments for 4 weeks. Symptoms were assessed at clinic visits after 2 and 4 weeks. RESULTS: Symptom relief after 4 weeks was achieved by 61% (OM20), 49% (OM10), and 40% (RAN) patients (OM20 versus OM10, P < 0.0167; OM20 versus RAN, P < 0.0001; OM10 versus RAN, P < 0.01). Among the patients (32%) with erosive reflux oesophagitis, symptom relief was achieved in 79% (OM20), 48% (OM10), and 33% (RAN) (OM20 versus OM10, P < 0.0001; OM20 versus RAN, P < 0.0001; OM1O versus RAN, NS). CONCLUSION: Omeprazole, 20 mg, is the most effective initial therapy for relief of GORD symptoms.  相似文献   
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