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1.
Sixty-two women (mean age 68.7 +/- 0.9 yr) with postmenopausal spinal osteoporosis were treated with cyclical etidronate therapy (400 mg for 2 weeks alternating with 12 weeks of 1 gm elemental calcium and 400 IU Vitamin D3) for a minimum of 2 yr. Bone mineral density (BMD) of the lumbar spine (g/cm2) increased significantly (p < 0.0001) after yr 1 (4.1 +/- 0.5 per cent) and yr 2 compared with yr 1 (2.2 +/- 0.5 per cent). The response rate was 89 per cent after yr 1 and 84 per cent after yr 2. BMD of the hip (30 patients) increased by 1.5 +/- 0.9 per cent after yr 1 and 5.5 +/- 1.1 per cent (p < 0.0001) after yr 2 when compared with baseline. The response rate was 63 per cent after yr 1 and 80 per cent after yr 2. Smaller numbers of patients continued with treatment up to 4 yr with no adverse long-term effects.  相似文献   
2.
Voltage switching induced by long-wavelength infrared light from a CO2 laser was observed using a double-barrier resonant tunneling diode (RTD) biased in the bistable region and the intersubband transition (IT) between the quantum confined states. Possible optoelectronic and all-optical switching applications involving hysteresis are proposed and discussed  相似文献   
3.
This project reports the publication of a variety of existing curricular resources for emergency medicine on the global Internet in a format that allows hypertext links between related material, timely updates, and end-user feedback. Curricular elements were converted to Hypertext Markup Language with extensive links between related content. The completed document contains instructions for curriculum development, specific curricula for subspecialty areas within a residency, reading lists for subspecialty curricula, banks of images, and board-type questions with answers. Users are provided with a mechanism to provide immediate feedback to section editors with suggestions for changes, including new references. Access to all or part of the document can be controlled via passwords, but is potentially available to anyone with an Internet connection and a World Wide Web browser. The document may by viewed on the World Wide Web at: http:@www.brown.edu@Administration@emergency_Medicine@ curr.html.  相似文献   
4.
5.
The axisymmetric Laplace equation is solved numerically to extract contact-angle data for a flat liquid/vapor interface contacting a submerged hemispherical solid. The liquid/vapor interface is treated as a membrane, with a membrane tension equal to the surface energy of the liquid. By measuring the vertical displacement of the membrane and the projected contact area the membrane makes with the hemisphere, the contact angle and correspondingly the driving force for motion of the contact line can be measured. We show that characteristic receding and advancing contact angles can be obtained by measuring the contact radii formed upon initial contact between the interface and hemisphere and final contact just prior to detachment of the interface, respectively. Use of the technique is illustrated with a model experiment involving the contact of an air/water interface with a poly(methyl methacrylate) surface.  相似文献   
6.
This study examined the nature and impact of dyadic perfectionism over a 3-month interval within a sample of 116 college students who were currently involved in an intimate heterosexual relationship. Dyadic perfectionism scores were stable and correlated as expected with scores on concurrent measures of adult attachment orientations and relationship satisfaction. Logistic regression analyses revealed that, controlling for initial commitment status and adult attachment orientations, Time 1 dyadic perfectionism scores significantly and uniquely predicted relationship continuity 3 months later. Lastly, controlling for social desirability, relationship commitment status, and Time 1 adult attachment orientation scores, Time 1 dyadic perfectionism scores also uniquely predicted Time 2 relationship distress. Findings provide additional evidence that dyadic perfectionism is a risk factor for relationship dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Predicted that high self-esteem Ss (HSEs) would rationalize an esteem-threatening decision less than low self-esteem Ss (LSEs), because HSEs presumably had more favorable self-concepts with which to affirm, and thus repair, their overall sense of self-integrity. This prediction was supported in 2 experiments within the "free-choice" dissonance paradigm: one that manipulated self-esteem through personality feedback and the other that varied it through selection of HSEs and LSEs, but only when Ss were made to focus on their self-concepts. A 3rd experiment countered an alternative explanation of the results in terms of mood effects that may have accompanied the experimental manipulations. Results were discussed in terms of the following: (1) their support for a resources theory of individual differences in resilience to self-image threats—an extension of self-affirmation theory, (2) their implications for self-esteem functioning, and (3) their implications for the continuing debate over self-enhancement vs self-consistency motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Intakes of grass silage and yield and composition of milk were examined in cows given high-protein diets to which two quantities of soybean oil had been added either as intracellular or extracellular inclusions. Adding extra protein to the diet did not prevent reduction of dry matter intakes of forage when soybean oil was added to the diet of cows. There is a fundamental difference in the mechanism by which high-starch diets reduce intake of forage dry matter from that of high-oil diets. In diets containing extracellular unsaturated oils, concentration of oil in the total ration, not the amount of oil per se, is the primary determinant reducing milk fat percentage.  相似文献   
9.
Optoelectronic properties of asymmetrically strained II-VI CdZnTe single-quantum-well structures grown by molecular-beam epitaxy are reported. Indium doping CdZnTe n-type using a two-dimensional electron gas heterostructure achieved a carrier mobility of 5000 cm2·V-1 s-1 at 40 K. A shallow donor ionization energy of 14.5 meV was determined from Hall effect measurements. Fabrication of a large-area-mesa heterostructure device allowed us to investigate exciton absorption of the mixed type-I and type-II single quantum well. Control of the electron concentration in the quantum well allows optical absorption modulation using both the quantum-confined Stark effect (QCSE) and phase-space absorption quenching. Separation of electron and hole photocurrents in different layers is demonstrated and results in photogain. A heavy-hole red-shift of 9.9 meV/V due to the reverse QCSE is reported  相似文献   
10.
This study examines the extent to which variations in consumers' sensory assessments of food arise from the inability to report accurately sensory perceptions, from confusion regarding the criteria by which to assess samples, or from differences in their oral breakdown of the products.

Twenty consumers assessed the tenderness of a range of 8 hot, freshly roasted meat samples using Time Intensity (TI). Overall a significant correlation was found between the maximum recorded intensity (Imax) of their TI curves and single sensory scores given by a trained panel. Correlation was significant for only 42% of the consumers individually. Significant correlations were found between the amount of masticatory muscle activity undertaken during chewing (measured using electromyography) and Imax for all but 2 of the consumers. Thus subjects' perceptions were accurately described by their chewing work, suggesting between subject differences in perception arose from differences in the way chewing work was applied to break down the samples. The sensory input from the masticatory muscles may represent the major determinant of perceived tenderness of meat.  相似文献   

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